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Sample records for fluoride-containing dental materials

  1. Fluoride release and recharge abilities of contemporary fluoride-containing restorative materials and dental adhesives.

    Science.gov (United States)

    Dionysopoulos, Dimitrios; Koliniotou-Koumpia, Eugenia; Helvatzoglou-Antoniades, Maria; Kotsanos, Nikolaos

    2013-01-01

    The aim of this study was to evaluate the fluoride release of five fluoride-releasing restorative materials and three dental adhesives, before and after NaF solution treatment. Five restorative materials (Fuji IX GP, GC Corp.; Ketac N100, 3M ESPE; Dyract Extra, Dentsply; Beautifil II, Shofu Inc.; Wave, SDI) and three dental adhesives (Stae, SDI; Fluorobond II - Shofu Inc.; Prime & Bond NT, Dentsply) were investigated before and after NaF solution treatment. A fluoride ion-selective electrode was to measure fluoride concentrations. During the 86-day period before NaF solution treatment, Fuji IX GP released the highest amount of fluoride among the restorative materials while Prime & Bond NT was the highest among the dental adhesives. After NaF solution treatment, Fuji IX GP again ranked the highest in fluoride release among the restorative materials while Fluorobond II ranked the highest among dental adhesives. It was concluded that the compositions and setting mechanisms of fluoride-containing dental materials influenced their fluoride release and recharge abilities.

  2. [The effects of topical fluoridation of Ketac Molar Aplicap glass-ionomer material on the growth of cariogenic bacteria contained in the dental plaque].

    Science.gov (United States)

    Płuciennik-Stronias, Małgorzata; Zarzycka, Beata; Bołtacz-Rzepkowska, Elzbieta

    2013-01-01

    Dental caries is a bacterial disease. The most important element used in caries prevention is fluoride, which is derived from the air, diet or fluoride-containing preparations and materials, e.g. glass-ionomer restorations. Modern fluoride-containing restorative materials are capable of releasing fluoride to the environment. Fluoride can be also accumulated in glass-ionomer cements, thus an attempt was made to saturate these materials with fluoride. The aim of the study was to evaluate the effect of topical fluoridation of Ketac Molar Aplicap glass-ionomer cement on the growth of Lactobacillus spp. in the dental plaque. The study was carried out in 15 patients with good oral hygiene, in whom 35 fillings with conventional glass-ionomer material, Ketac Molar Aplicap, were performed. After 6 months, three-day dental plaque from these fillings was examined. Next, fluoride was rubbed on the glass-ionomer surface and the examination of three-day dental plaque was repeated. No statistically significant differences (p = 0.143) in the amounts of Lactobacillus spp. in the plaque collected prior to and after topical fluoridation were revealed. Fluoride rubbed in the conventional glass-ionomer cement, Ketac Molar Aplicap, did not affect the amount of Lactobacillus spp. in the dental plaque growing on this material.

  3. [The effects of topical fluoridation of enamel on the growth of cariogenic bacteria contained in the dental plaque].

    Science.gov (United States)

    Płuciennik-Stronias, Małgorzata; Zarzycka, Beata; Bołtacz-Rzepkowska, Elzbieta

    2013-01-01

    Dental caries is a bacterial disease. The most important element used in caries prevention is fluoride, which is derived from the air, diet or fluoride-containing preparations and materials, e.g. glass-ionomer restorations. Fluoride can inhibit metabolism and bacterial growth in the dental plaque. The aim of the study was to evaluate the effect of topical fluoridation of the enamel on the growth of Lactobacillus spp. in the dental plaque. The study was carried out in 15 patients with good oral hygiene, in whom three-day dental plaque from the enamel was examined. Next, fluoride was rubbed on the same surface and the examination of three-day dental plaque was repeated. No statistically significant differences (p = 0.475) in the amounts of Lactobacillus spp. in the plaque collected prior to and after the topical fluoridation were revealed. Fluoride rubbed in the enamel, did not affect the amount of Lactobacillus spp. in the dental plaque growing on this material.

  4. Effect of fluoride addition on the properties of dental alginate impression materials.

    Science.gov (United States)

    Lee, Yong-Keun; Lim, Bum-Soon; Kim, Cheol-We

    2004-03-01

    Fluoride-containing dental alginate impression materials can exert a considerable reduction in enamel solubility. The objective was to evaluate the effects of fluoride addition in the alginate impression materials on the properties and subsequent release of fluoride. Four experimental alginate impression materials were studied. Materials were mixed with distilled water (control) or 100-ppm fluoride solution. One or two percent NaF, or 1% SnF2 was added to the materials, which were mixed with distilled water. Fluoride release, flexibility, recovery from deformation, setting time, compressive strength and elastic modulus were determined in accordance with the ISO 1563 and ANSI/ADA Spec. 18. Fluoride release increased after addition of fluoride, and the released amount was 0.762-14.761 ppm. Addition of NaF or SnF2 resulted in higher fluoride release than the control group (p alginate impression material may result in effective release of fluoride without deteriorating the properties of material itself.

  5. Fluorine uptake into human enamel around a fluoride-containing dental material during cariogenic pH cycling

    International Nuclear Information System (INIS)

    Komatsu, H.; Yamamoto, H.; Nomachi, M.; Yasuda, K.; Matsuda, Y.; Murata, Y.; Kijimura, T.; Sano, H.; Sakai, T.; Kamiya, T.

    2007-01-01

    the enamel adjacent to the material remained a caries inhibition zone due to low rate of demineralization. With caries progression, fluorine accumulated in the subsurface of the caries lesion, while the outermost surface of the caries lesion gradually dissolved under increasing pH cycling. The data obtained using PIGE (TIARA, JAPAN) technique were useful to understand the fluorine benefit for preventing dental caries by means of fluoride-containing dental materials

  6. Fluorine uptake into human enamel around a fluoride-containing dental material during cariogenic pH cycling

    Energy Technology Data Exchange (ETDEWEB)

    Komatsu, H. [Graduate School of Dental Medicine, Hokkaido University, Kita-13, Nishi-7, Kita-ku, Sapporo 060-8586 (Japan)]. E-mail: kom@den.hokudai.ac.jp; Yamamoto, H. [Graduate School of Dentistry, Osaka University, 1-8 Yamada-Oka, Suita 565-0871 (Japan); Nomachi, M. [Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka 560-0043 (Japan); Yasuda, K. [Wakasa wan Energy Research Center, 64-52-1 Hase, Tsuruga 914-0192 (Japan); Matsuda, Y. [Graduate School of Dental Medicine, Hokkaido University, Kita-13, Nishi-7, Kita-ku, Sapporo 060-8586 (Japan); Murata, Y. [Graduate School of Dental Medicine, Hokkaido University, Kita-13, Nishi-7, Kita-ku, Sapporo 060-8586 (Japan); Kijimura, T. [Graduate School of Dental Medicine, Hokkaido University, Kita-13, Nishi-7, Kita-ku, Sapporo 060-8586 (Japan); Sano, H. [Graduate School of Dental Medicine, Hokkaido University, Kita-13, Nishi-7, Kita-ku, Sapporo 060-8586 (Japan); Sakai, T. [Takasaki Advanced Radiation Research Institute, JAEA, 1233 Watanuki-machi, Takasaki 370-1292 (Japan); Kamiya, T. [Takasaki Advanced Radiation Research Institute, JAEA, 1233 Watanuki-machi, Takasaki 370-1292 (Japan)

    2007-07-15

    duration of pH cycling, although the enamel adjacent to the material remained a caries inhibition zone due to low rate of demineralization. With caries progression, fluorine accumulated in the subsurface of the caries lesion, while the outermost surface of the caries lesion gradually dissolved under increasing pH cycling. The data obtained using PIGE (TIARA, JAPAN) technique were useful to understand the fluorine benefit for preventing dental caries by means of fluoride-containing dental materials.

  7. Corrosion resistance of titanium-containing dental orthodontic wires in fluoride-containing artificial saliva

    International Nuclear Information System (INIS)

    Lee, T.-H.; Wang, C.-C.; Huang, T.-K.; Chen, L.-K.; Chou, M.-Y.; Huang, H.-H.

    2009-01-01

    This study was to investigate the corrosion resistance of different Ti-containing dental orthodontic wires (including Ni-Ti, Ni-Ti-Cu, Ti-Mo-Zr-Sn, and Ti-Nb alloys) in acidic fluoride-containing artificial saliva using cyclic potentiodynamic polarization curve measurements. Different NaF concentrations (0%, 0.2%, and 0.5%), simulating the fluoride contents in commercial toothpastes, were added to the artificial saliva. Surface characterization was analyzed using X-ray photoelectron spectrometry. Cyclic potentiodynamic polarization curves showed that the presence of fluoride ions, especially 0.5% NaF, was detrimental to the protective ability of the TiO 2 -based film on the Ti-containing wires. This might lead to a decrease in the corrosion resistance of the tested alloys, i.e. an increase in the corrosion rate and anodic current density and a decrease in the passive film breakdown potential. Among the tested Ti-containing wires, the Ni-Ti and Ni-Ti-Cu wires containing mainly TiO 2 on surface film were more susceptible to fluoride-enhanced corrosion, while the Ti-Mo-Zr-Sn and Ti-Nb wires containing MoO 3 /ZrO 2 /SnO and Nb 2 O 5 , respectively, along with TiO 2 on surface film were pitting corrosion resistant and showed a lower susceptibility to fluoride-enhanced corrosion. The difference in corrosion resistance of the tested commercial Ti-containing dental orthodontic wires was significantly dependent on the passive film characteristics on wires' surface.

  8. Corrosion resistance of titanium-containing dental orthodontic wires in fluoride-containing artificial saliva

    Energy Technology Data Exchange (ETDEWEB)

    Lee, T.-H. [Institute of Medicine, Chung Shan Medical University, Taichung 402, Taiwan (China); Department of Dentistry, Chung Shan Medical University Hospital, Taichung 402, Taiwan (China); Wang, C.-C. [Department of Dental Laboratory Technology, Min-Hwei College of Health Care Management, Tainan County 736, Taiwan (China); Huang, T.-K. [College of Dental Medicine, Kaohsiung Medical University, Kaohsiung 807, Taiwan (China); Chen, L.-K. [Department of Dentistry, Taipei City Hospital, Taipei 115, Taiwan (China); Chou, M.-Y. [Institute of Medicine, Chung Shan Medical University, Taichung 402, Taiwan (China); Department of Dentistry, Chung Shan Medical University Hospital, Taichung 402, Taiwan (China); Huang, H.-H., E-mail: hhhuang@ym.edu.t [Department of Dentistry, Taipei City Hospital, Taipei 115, Taiwan (China); Department of Dentistry, National Yang-Ming University, Taipei 112, Taiwan (China); Institute of Oral Biology, National Yang-Ming University, Taipei 112, Taiwan (China)

    2009-11-20

    This study was to investigate the corrosion resistance of different Ti-containing dental orthodontic wires (including Ni-Ti, Ni-Ti-Cu, Ti-Mo-Zr-Sn, and Ti-Nb alloys) in acidic fluoride-containing artificial saliva using cyclic potentiodynamic polarization curve measurements. Different NaF concentrations (0%, 0.2%, and 0.5%), simulating the fluoride contents in commercial toothpastes, were added to the artificial saliva. Surface characterization was analyzed using X-ray photoelectron spectrometry. Cyclic potentiodynamic polarization curves showed that the presence of fluoride ions, especially 0.5% NaF, was detrimental to the protective ability of the TiO{sub 2}-based film on the Ti-containing wires. This might lead to a decrease in the corrosion resistance of the tested alloys, i.e. an increase in the corrosion rate and anodic current density and a decrease in the passive film breakdown potential. Among the tested Ti-containing wires, the Ni-Ti and Ni-Ti-Cu wires containing mainly TiO{sub 2} on surface film were more susceptible to fluoride-enhanced corrosion, while the Ti-Mo-Zr-Sn and Ti-Nb wires containing MoO{sub 3}/ZrO{sub 2}/SnO and Nb{sub 2}O{sub 5}, respectively, along with TiO{sub 2} on surface film were pitting corrosion resistant and showed a lower susceptibility to fluoride-enhanced corrosion. The difference in corrosion resistance of the tested commercial Ti-containing dental orthodontic wires was significantly dependent on the passive film characteristics on wires' surface.

  9. Fluorine uptake into human enamel around fluoride-containing dental materials during cariogenic pH cycling

    Energy Technology Data Exchange (ETDEWEB)

    Komatsu, H. [Graduate School of Dental Medicine, Hokkaido University, Kita-13, Nishi-7, Kita-ku, Sapporo 060-8586 (Japan)], E-mail: kom@den.hokudai.ac.jp; Yamamoto, H. [Graduate School of Dentistry, Osaka University, 1-8 Yamada-Oka, Suita 565-0871 (Japan); Nomachi, M. [Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka 560-0043 (Japan); Yasuda, K. [The Wakasa wan Energy Research Center, 64-52-1 Hase, Tsuruga 914-0192 (Japan); Matsuda, Y.; Kinugawa, M.; Kijimura, T.; Sano, H. [Graduate School of Dental Medicine, Hokkaido University, Kita-13, Nishi-7, Kita-ku, Sapporo 060-8586 (Japan); Satou, T.; Oikawa, S.; Kamiya, T. [Advanced Radiation Technology, TARRI, JAEA, 1233 Watanuki-machi, Takasaki 370-1292 (Japan)

    2009-06-15

    Using PIGE (Proton Induced Gamma Emission) technique at TARRI (Takasaki Advanced Radiation Research Institute), Japan, we measured fluorine (F) uptake into the tooth enamel around two fluoride-containing materials during caries progression using pH cycling. Class V cavities in extracted human teeth were drilled and filled with fluoride-containing materials (i.e. 'Fuji IX' (FN) and 'UniFil flow with MEGA bond' (UF)) and a non-fluoride-containing material (i.e. 'SOLARE with MEGA bond' (SO)). Three 120 {mu}m longitudinal sections including the filling material were obtained from each tooth. In order to simulate daily acid attack occurring in the oral cavity, the pH cycling (pH 6.8-4.5) was carried out for 1, 3 and 5 weeks, separately. After pH cycling, the caries progression in all specimens was observed using transverse microradiography (TMR). The F and calcium distributions of the specimens were evaluated using PIGE and PIXE techniques. The F distribution of the specimens clearly showed the F uptake from FN into enamel adjacent to the filling material, while the F uptakes from UF and SO were not detected. For UF, the MEGA bond (non-fluoride-containing) between the tooth and UniFil flow interfered with the F absorption into the tooth. For FN, the amount of F uptake into the subsurface enamel increased during pH cycling. The amount of F uptake in 5-week pH cycling had significantly higher value compared to those in 1- and 3-week pH cycling. For UF and SO, there were no significant differences between the different durations of pH cycling. Among fluoride-containing materials, there were some differences in the F uptake with increased pH cycling, which could possibly lead to obtaining difference in clinical performance. The data obtained using PIGE and PIXE techniques were useful in understanding the benefit of fluorine by means of fluoride-containing material for preventing caries.

  10. Fluorine uptake into human enamel around fluoride-containing dental materials during cariogenic pH cycling

    International Nuclear Information System (INIS)

    Komatsu, H.; Yamamoto, H.; Nomachi, M.; Yasuda, K.; Matsuda, Y.; Kinugawa, M.; Kijimura, T.; Sano, H.; Satou, T.; Oikawa, S.; Kamiya, T.

    2009-01-01

    Using PIGE (Proton Induced Gamma Emission) technique at TARRI (Takasaki Advanced Radiation Research Institute), Japan, we measured fluorine (F) uptake into the tooth enamel around two fluoride-containing materials during caries progression using pH cycling. Class V cavities in extracted human teeth were drilled and filled with fluoride-containing materials (i.e. 'Fuji IX' (FN) and 'UniFil flow with MEGA bond' (UF)) and a non-fluoride-containing material (i.e. 'SOLARE with MEGA bond' (SO)). Three 120 μm longitudinal sections including the filling material were obtained from each tooth. In order to simulate daily acid attack occurring in the oral cavity, the pH cycling (pH 6.8-4.5) was carried out for 1, 3 and 5 weeks, separately. After pH cycling, the caries progression in all specimens was observed using transverse microradiography (TMR). The F and calcium distributions of the specimens were evaluated using PIGE and PIXE techniques. The F distribution of the specimens clearly showed the F uptake from FN into enamel adjacent to the filling material, while the F uptakes from UF and SO were not detected. For UF, the MEGA bond (non-fluoride-containing) between the tooth and UniFil flow interfered with the F absorption into the tooth. For FN, the amount of F uptake into the subsurface enamel increased during pH cycling. The amount of F uptake in 5-week pH cycling had significantly higher value compared to those in 1- and 3-week pH cycling. For UF and SO, there were no significant differences between the different durations of pH cycling. Among fluoride-containing materials, there were some differences in the F uptake with increased pH cycling, which could possibly lead to obtaining difference in clinical performance. The data obtained using PIGE and PIXE techniques were useful in understanding the benefit of fluorine by means of fluoride-containing material for preventing caries.

  11. Fluoride-releasing restorative materials and secondary caries.

    Science.gov (United States)

    Hicks, John; Garcia-Godoy, Franklin; Donly, Kevin; Flaitz, Catherine

    2003-03-01

    Secondary caries is responsible for 60 percent of all replacement restorations in the typical dental practice. Risk factors for secondary caries are similar to those for primary caries development. Unfortunately, it is not possible to accurately predict which patients are at risk for restoration failure. During the past several decades, fluoride-releasing dental materials have become a part of the dentist's armamentarium. Considerable fluoride is released during the setting reaction and for periods up to eight years following restoration placement. This released fluoride is readily taken up by the cavosurface tooth structure, as well as the enamel and root surfaces adjacent to the restoration. Resistance against caries along the cavosurface and the adjacent smooth surface has been shown in both in vitro and in vivo studies. Fluoride-releasing dental materials provide for improved resistance against primary and secondary caries in coronal and root surfaces. Plaque and salivary fluoride levels are elevated to a level that facilitates remineralization. In addition, the fluoride released to dental plaque adversely affects the growth of lactobacilli and mutans streptococci by interference with bacterial enzyme systems. Fluoride recharging of these dental materials is readily achieved with fluoridated toothpastes, fluoride mouthrinses, and other sources of topical fluoride. This allows fluoride-releasing dental materials to act as intraoral fluoride reservoirs. The improvement in the properties of dental materials with the ability to release fluoride has improved dramatically in the past decade, and it is anticipated that in the near future the vast majority of restorative procedures will employ fluoride-releasing dental materials as bonding agents, cavity liners, luting agents, adhesives for orthodontic brackets, and definitive restoratives.

  12. [The effect of fluoride-containing tooth paste on dental plaque and on fluoride level in the mouth].

    Science.gov (United States)

    Oomori, H

    1989-01-01

    Various kinds of fluoride have been used for a long time and there are many reports concerning fluorides and their effects. Recently, the caries-inhibiting action of fluoride-containing tooth paste has been given much attention. In this study, I tried to clarify the residual time and amount of fluoride derived from the fluoride-containing tooth paste in the mouth, as well as to assess possible variation in bacterial composition in the dental plaque bacteriologically and biochemically. In the study on the fluoride clearance from the mouth, both 1.0 g and 0.5 g of paste showed the same reduction rates; and about an 80% reduction was recognized between the value at 3 minutes and that at 30 minutes, and about a 40% reduction from the 30-minute to the 60-minute interval. Next, a study on the variation in plaque bacteria was carried out. The total number of the CFU on each plate was not different between samples obtained before and after the use of the tooth paste; moreover, no difference was noted between aerobic and anaerobic culture. However, when plaque before and after brushing with fluoride-containing tooth paste were cultured in 10% sucrose solution, the differences of acid production such as lactic acid, acetic acid, and formic acid were demonstrated. Namely, these acid productions were inhibited after the use of fluoride, especially lactic acid was strongly inhibited. On the other hand, when Str. mutans from the plaque obtained after the use of fluoride-containing tooth paste was cultured in fluoride-free BHI broth, the inhibition of acid from carbohydrates was not shown clearly.(ABSTRACT TRUNCATED AT 250 WORDS)

  13. Fluoride uptake from restorative dental materials by human enamel

    International Nuclear Information System (INIS)

    Forsten, L.; Rytoemaa, I.; Anttila, A.; Keinonen, J.

    1976-01-01

    The purpose of the study was to determine the uptake in vitro of fluoride from restorative materials by tooth enamel and whether prior etching of the enamel causes a change of uptake. The outermost layer of the labial surface of extracted canines was removed by grinding and the enamel was covered with five different fluoride-containing materials ; a silicate, a composite resin, an amalgam, a silicophosphate, and a polycarboxylate luting cement. The material was either removed immediately or after storing the tooth in distilled water. The fluoride content was determined using a sensitive physical method based on the 19 F (p, αγ) 16 O reaction. In addition, the fluoride content of enamel after etching for different periods of time and of etched enamel which had been in contact with silicate cement was determined. The mean fluoride content of uncovered interior enamel was 226 parts 10 6 . All materials, except the composite, increased clearly the fluoride content of the underlying enamel. Etching of interior enamel also increased the fluoride values. No difference could be shown in fluoride uptake from silicate and composite resin between etched and unetched enamel. (author)

  14. Protection From Dental Erosion: All Fluorides are Not Equal.

    Science.gov (United States)

    Faller, Robert V; Noble, Warden H

    2018-03-01

    All fluoride sources help strengthen teeth against bacterial acids that cause caries. However, excessive exposure to dietary acids, which can result in dental erosion, presents a more aggressive level of challenge compared to caries. Despite the fact that almost all toothpastes contain fluoride, both the incidence and prevalence of dental erosion appear to be on the rise. This article: (1) describes key differences between caries and dental erosion and the ability of different fluoride sources to help prevent erosion; (2) discusses the importance of the evaluation of patients for dental erosion at the earliest stages using the Basic Erosive Wear Examination scoring system to help assess and educate patients; and (3) provides evidence-based information for making specific recommendations to patients with dental erosion. The objective of this article is to assess the comparative ability of fluoride agents to protect against dental erosion. Though all fluorides are able to help strengthen teeth against cariogenic acids, not all available sources of fluoride provide the same level of erosion protection. Daily use of a stabilized stannous fluoride dentifrice has been shown to provide the most effective means of protecting teeth against the increasing risk of dental erosion and erosive tooth wear.

  15. Review on fluoride-releasing restorative materials--fluoride release and uptake characteristics, antibacterial activity and influence on caries formation.

    Science.gov (United States)

    Wiegand, Annette; Buchalla, Wolfgang; Attin, Thomas

    2007-03-01

    The purpose of this article was to review the fluoride release and recharge capabilities, and antibacterial properties, of fluoride-releasing dental restoratives, and discuss the current status concerning the prevention or inhibition of caries development and progression. Information from original scientific full papers or reviews listed in PubMed (search term: fluoride release AND (restorative OR glass-ionomer OR compomer OR polyacid-modified composite resin OR composite OR amalgam)), published from 1980 to 2004, was included in the review. Papers dealing with endodontic or orthodontic topics were not taken into consideration. Clinical studies concerning secondary caries development were only included when performed in split-mouth design with an observation period of at least three years. Fluoride-containing dental materials show clear differences in the fluoride release and uptake characteristics. Short- and long-term fluoride releases from restoratives are related to their matrices, setting mechanisms and fluoride content and depend on several environmental conditions. Fluoride-releasing materials may act as a fluoride reservoir and may increase the fluoride level in saliva, plaque and dental hard tissues. However, clinical studies exhibited conflicting data as to whether or not these materials significantly prevent or inhibit secondary caries and affect the growth of caries-associated bacteria compared to non-fluoridated restoratives. Fluoride release and uptake characteristics depend on the matrices, fillers and fluoride content as well as on the setting mechanisms and environmental conditions of the restoratives. Fluoride-releasing materials, predominantly glass-ionomers and compomers, did show cariostatic properties and may affect bacterial metabolism under simulated cariogenic conditions in vitro. However, it is not proven by prospective clinical studies whether the incidence of secondary caries can be significantly reduced by the fluoride release of

  16. Poisoning by coal smoke containing arsenic and fluoride

    Energy Technology Data Exchange (ETDEWEB)

    An, D.; He, Y.G.; Hu, Q.X. [Guizhou Sanitary and Epidemiological Station, Guiyang (China)

    1997-02-01

    An investigation was made into a disease involving skin pigmentation, keratosis of the hands and feet, dental discoloration, and generalized bone and joint pain, stiffness and rigidity, in the village of Bazhi, Zhijin County, Ghizhou Province, People`s Republic of China. Measurements were made of the arsenic and fluoride levels of coal, water, air, food, urine and hair in Bazhi and a control village, Xinzhai, in which coal with a low arsenic content was used. Up to 188 people, including children, in Bazhi and 752 in Xinzhai, were examined for the presence of chronic arsenium, skeletal fluorosis, dental fluorosis and electrocardiogram abnormalities. The coal in Bazhi was found to contain high levels of arsenic and fluoride resulting, after burning in homes without an adequate chimney systems, in pollution of air and food with arsenic and fluoride. The coal in Xinzhai did not cause arsenic pollution but did produce a higher level of fluoride pollution. It was concluded that the endemic disease in Bazhi was caused by pollution by coal smoke containing arsenic and fluoride. It is suggested that arsenic may act synergistically with fluoride so that a lower level of fluoride may produce fluoride toxicity with dental and skeletal fluorosis.

  17. Equity in children's dental caries before and after cessation of community water fluoridation: differential impact by dental insurance status and geographic material deprivation.

    Science.gov (United States)

    McLaren, Lindsay; McNeil, Deborah A; Potestio, Melissa; Patterson, Steve; Thawer, Salima; Faris, Peter; Shi, Congshi; Shwart, Luke

    2016-02-11

    One of the main arguments made in favor of community water fluoridation is that it is equitable in its impact on dental caries (i.e., helps to offset inequities in dental caries). Although an equitable effect of fluoridation has been demonstrated in cross-sectional studies, it has not been studied in the context of cessation of community water fluoridation (CWF). The objective of this study was to compare the socio-economic patterns of children's dental caries (tooth decay) in Calgary, Canada, in 2009/10 when CWF was in place, and in 2013/14, after it had been discontinued. We analyzed data from population-based samples of schoolchildren (grade 2) in 2009/10 and 2013/14. Data on dental caries (decayed, missing, and filled primary and permanent teeth) were gathered via open mouth exams conducted in schools by registered dental hygienists. We examined the association between dental caries and 1) presence/absence of dental insurance and 2) small area index of material deprivation, using Poisson (zero-inflated) and logistic regression, for both time points separately. For small-area material deprivation at each time point, we also computed the concentration index of inequality for each outcome variable. Statistically significant inequities by dental insurance status and by small area material deprivation were more apparent in 2013/14 than in 2009/10. Results are consistent with increasing inequities in dental caries following cessation of CWF. However, further research is needed to 1) confirm the effects in a study that includes a comparison community, and 2) explore possible alternative reasons for the findings, including changes in treatment and preventive programming.

  18. Dental fluorosis and urinary fluoride in 10-12 years old adolescents of Bushehr port

    OpenAIRE

    Giti Javan; Ehsan Mostaghni; Seyed Mojtaba Jafary; Batoul Amini; Bahram Hematinejad

    2006-01-01

    Background: Fluoride increases tooth resistance to dental caries, but mild toxicity due to excessive ingestion of fluoride can cause dental fluorosis. Drinking water naturally contains fluoride and is a major source of fluoride. In Bushehr port, drinking water is supplied from limestone springs with normal fluoride levels but dental fluorosis is observed. Methods: A total of 95 native school children (between the ages of 10-12 years old) were randomly selected from four Bushehr port regions. ...

  19. Fluoride release, recharge and flexural properties of polymethylmethacrylate containing fluoridated glass fillers.

    Science.gov (United States)

    Al-Bakri, I A; Swain, M V; Naoum, S J; Al-Omari, W M; Martin, E; Ellakwa, A

    2014-06-01

    The purpose of this study was to investigate the effect of fluoridated glass fillers on fluoride release, recharge and the flexural properties of modified polymethylmethacrylate (PMMA). Specimens of PMMA denture base material with various loading of fluoridated glass fillers (0%, 1%, 2.5%, 5% and 10% by weight) were prepared. Flexural properties were evaluated on rectangular specimens (n = 10) aged in deionized water after 24 hours, 1 and 3 months. Disc specimens (n = 10) were aged for 43 days in deionized water and lactic acid (pH 4.0) and fluoride release was measured at numerous intervals. After ageing, specimens were recharged and fluoride re-release was recorded at 1, 3 and 7 days after recharge. Samples containing 2.5%, 5% and 10% glass fillers showed significantly (p glass fillers specimens. All experimental specimens exhibited fluoride release in both media. The flexural strength of specimens decreased in proportion to the percentage filler inclusion with the modulus of elasticity values remaining within ISO Standard 1567. The modified PMMA with fluoridated glass fillers has the ability to release and re-release fluoride ion. Flexural strength decreased as glass filler uploading increased. © 2014 Australian Dental Association.

  20. Dental fluorosis and urinary fluoride in 10-12 years old adolescents of Bushehr port

    Directory of Open Access Journals (Sweden)

    Giti Javan

    2006-02-01

    Full Text Available Background: Fluoride increases tooth resistance to dental caries, but mild toxicity due to excessive ingestion of fluoride can cause dental fluorosis. Drinking water naturally contains fluoride and is a major source of fluoride. In Bushehr port, drinking water is supplied from limestone springs with normal fluoride levels but dental fluorosis is observed. Methods: A total of 95 native school children (between the ages of 10-12 years old were randomly selected from four Bushehr port regions. Dental fluorosis, height and weight were examined. Probable attributing factors of dental fluorosis were also questioned. A 16 to 18 hours urinary fluoride concentration was measured with a fluoride ion selective electrode. Results: Dental fluorosis in four upper incisors was apparent in 52.6 % of the subjects. The urinary fluoride concentration was 2.18 mg/lit. Fluoride concentration in drinking water of schools ranged from 0.41 to 0.58 mg/lit. Forty percent of subjects were caries free. Conclusion: In spite of the normal range of fluoride concentration in the drinking water of Bushehr, dental fluorosis and urinary fluoride concentration are higher than the recommended ranges. Therefore, it is necessary to further investigate the amount and effects of fluoride ingestion in residents of Bushehr province.

  1. [The effects of Ketac Molar Aplicap glass-ionomer material on growth of cariogenic bacteria contained in the dental plaque].

    Science.gov (United States)

    Płuciennik-Stronias, Małgorzata; Sakowska, Danuta; Paul-Stalmaszczyk, Małgorzata; Bołtacz-Rzepkowska, Elzbieta

    2012-01-01

    In the aging population, the prevalence of root caries has been observed, which is a characteristic feature of the elderly people. The most important element used in caries prevention is fluoride, which is derived from the air, diet or fluoride-containing preparations and materials, e.g. glass-ionomer restorations. The aim of the study was to evaluate the effect of Ketac Molar Aplicap glass-ionomer on the growth of Lactobacillus sp. bacteria, one of the species most frequently found in the carietic focus of the tooth root. The study was carried out in 15 patients with good oral hygiene, in whom 35 fillings from Ketac Molar Aplicap conventional glass-ionomer material were performed. After 6 months, three-day dental plaque from these fillings and from the tooth enamel of the control group was examined. No statistically significant differences (p = 0.554) in the amounts of Lactobacillus sp. between the study and control group were revealed. Lack of inhibiting effect of glass-ionomer material on the growth of the dental plaque with Lactobacillus sp. after the time of observation is implied.

  2. An Investigation of Fluoride Concentration in Drinking Water of Sanganer Tehsil, Jaipur District, Rajasthan, India and Defluoridation from Plant Material

    Directory of Open Access Journals (Sweden)

    Mohammed Arif

    2014-01-01

    Full Text Available Forty water samples of 20 villages of Sanganer tehsil, Jaipur district were analyzed for determining fluoride ion concentrations. High fluoride containing regions were identified on the basis of fluoride levels of the water samples and also on the prevalence rate of dental and skeletal fluorosis of the study area. Fluoride maps, which distinguish the regions containing the water sources of different ranges of fluoride ion concentrations, were also prepared by isopleth’s technique, a statistical method. Water samples containing high fluoride levels were defluoridated with low-cost materials prepared from plant byproducts. These materials successfully decrease the fluoride ions concentration to an acceptable limit (from 0.5 to 1.5 mg/L without disturbing drinking water quality standards.

  3. Fluoride use in Controlling Dental Caries and Fluorosis

    Directory of Open Access Journals (Sweden)

    Gaurav Solanki

    2012-07-01

    Full Text Available Policy were introduced to control fluoride exposure and to reduce the prevalence of fluorosis. The study aimed of describing the prevalence, severity and risk factors for fluorosis, and to describe the trend of fluorosis among Indian children. The study also aimed of exploring the effect of the change in fluoride exposure on dental fluorosis and caries. Establishing an appropriate use of fluoride toothpaste could be successful in reducing fluorosis without a significant increase in caries experience. The use of fluorides for oral health has always involved a balance between the protective benefit against dental caries and the risk of developing fluorosis. The link between fluoride and dental health was established to determining the causes of dental fluorosis or enamel mottling. Fluorosis in Indian children was highly prevalent in the early 1990s.

  4. Chronic Fluoride Toxicity: Dental Fluorosis

    OpenAIRE

    DenBesten, Pamela; Li, Wu

    2011-01-01

    Dental fluorosis occurs as a result of excess fluoride ingestion during tooth formation. Enamel fluorosis and primary dentin fluorosis can only occur when teeth are forming, and therefore fluoride exposure (as it relates to dental fluorosis) occurs during childhood. In the permanent dentition, this would begin with the lower incisors, which complete mineralization at approximately 2–3 years of age, and end after mineralization of the third molars. The white opaque appearance of fluorosed enam...

  5. Chronic fluoride toxicity: dental fluorosis.

    Science.gov (United States)

    Denbesten, Pamela; Li, Wu

    2011-01-01

    Dental fluorosis occurs as a result of excess fluoride ingestion during tooth formation. Enamel fluorosis and primary dentin fluorosis can only occur when teeth are forming, and therefore fluoride exposure (as it relates to dental fluorosis) occurs during childhood. In the permanent dentition, this would begin with the lower incisors, which complete mineralization at approximately 2-3 years of age, and end after mineralization of the third molars. The white opaque appearance of fluorosed enamel is caused by a hypomineralized enamel subsurface. With more severe dental fluorosis, pitting and a loss of the enamel surface occurs, leading to secondary staining (appearing as a brown color). Many of the changes caused by fluoride are related to cell/matrix interactions as the teeth are forming. At the early maturation stage, the relative quantity of amelogenin protein is increased in fluorosed enamel in a dose-related manner. This appears to result from a delay in the removal of amelogenins as the enamel matures. In vitro, when fluoride is incorporated into the mineral, more protein binds to the forming mineral, and protein removal by proteinases is delayed. This suggests that altered protein/mineral interactions are in part responsible for retention of amelogenins and the resultant hypomineralization that occurs in fluorosed enamel. Fluoride also appears to enhance mineral precipitation in forming teeth, resulting in hypermineralized bands of enamel, which are then followed by hypomineralized bands. Enhanced mineral precipitation with local increases in matrix acidity may affect maturation stage ameloblast modulation, potentially explaining the dose-related decrease in cycles of ameloblast modulation from ruffle-ended to smooth-ended cells that occur with fluoride exposure in rodents. Specific cellular effects of fluoride have been implicated, but more research is needed to determine which of these changes are relevant to the formation of fluorosed teeth. As further

  6. Fluorine uptake into the human enamel surface from fluoride-containing sealing materials during cariogenic pH cycling

    Science.gov (United States)

    Yasuhiro, Matsuda; Katsushi, Okuyama; Hiroko, Yamamoto; Hisanori, Komatsu; Masashi, Koka; Takahiro, Sato; Naoki, Hashimoto; Saiko, Oki; Chiharu, Kawamoto; Hidehiko, Sano

    2015-04-01

    To prevent the formation of caries and reduce dentin hypersensitivity, sealing materials, either with or without fluoride, are generally applied on the tooth in clinical practice. Application of fluoride-free sealing materials results in the formation of an acid-resistant layer on the tooth surface. On the other hand, fluoride-containing sealing materials might not only form an acid-resistant layer but could possibly further provide fluoride to enhance remineralization and reduce demineralization. In this study, the demineralization prevention ability and fluorine uptake rate in human enamel of fluoride-containing sealing materials ["MS coats F" (MSF)] and fluoride-free sealing materials ("hybrid coats 2" [HI]) were evaluated using an automatic pH cycling system. Each material was applied to the original tooth surface, the cut surfaces were covered with sticky wax, and the automatic pH-cycling system simulated daily acid changes (pH 6.8-4.5) occurring in the oral cavity for 4 weeks. Caries progression was analyzed using transverse microradiography (TMR) taken pre and post the 4 weeks of pH cycling. The fluorine and calcium distributions in the carious lesion in each specimen were evaluated using the proton-induced gamma emission (PIGE) and proton-induced X-ray (PIXE) techniques, respectively. TMR analysis showed that both MSF and HI had a caries-preventing effect after 4 weeks of pH cycling. PIGE/PIXE analysis demonstrated that only MSF resulted in fluoride uptake in the enamel surface. Therefore, MSF can help to form an acid-resistant layer and provide fluoride to the enamel surface. The presence of fluoride on the enamel surface suggested that MSF could prevent demineralization, even if the acid-resistant layer was removed, in clinical settings. The data obtained using the PIGE and PIXE techniques are useful for understanding the benefits of the use of a fluoride-containing sealing material for preventing caries.

  7. IMPACT OF FLUORIDE ON DENTAL HEALTH QUALITY.

    Science.gov (United States)

    Medjedovic, Eida; Medjedovic, Senad; Deljo, Dervis; Sukalo, Aziz

    2015-12-01

    Fluoride is natural element that strengthens teeth and prevents their decay. Experts believe that the best way to prevent cavities is the use of fluoride from multiple sources. Studies even show that in some cases, fluoride can stop already started damage of the teeth. In children younger than 6 years fluoride is incorporated into the enamel of permanent teeth, making the teeth more resistant to the action of bacterial and acids in food. The aim of this study is to determine the effects of improving the health status of teeth after six months treatment with the use of topical fluoridation 0.5% NaF, and the level and quality of the impact of treatment with chemical 0.5% NaF on the dental health of children at age from 8 to 15 years, in relation to gender and chronological age. This study included school children aged 8 to 15 years who visited health and dental services dependent in Mostar. It is obvious that after the implementation of treatment with 5% NaF by the method of topical fluoridation, health status of subjects from the experimental group significantly improved, so that at the final review 89.71% or 61 subjects of the experimental group had healthy (cured teeth), tooth with dental caries only 5.88% or 4 respondents tooth with dental caries and filling 4.41% or 3 respondents, extracted baby tooth 14.71% or 10 respondents, while for 13.24% of respondents was identified state with still unerupted teeth. Our findings are indirectly confirmed that the six-month treatment of fluoridation with 5% NaF, contributed to statistically significant improvement in overall oral health of the experimental group compared to the control group which was not treated by any dental treatment. It can be concluded that there is a statistically significant difference in the evaluated parameters of oral health of children in the control group compared to the studied parameters of oral health the experimental group of children at the final dental examination.

  8. Fluorine uptake into the human enamel surface from fluoride-containing sealing materials during cariogenic pH cycling

    Energy Technology Data Exchange (ETDEWEB)

    Yasuhiro, Matsuda, E-mail: matsuda@den.hokudai.ac.jp [Department of Restorative Dentistry, Graduate School of Dental Medicine Hokkaido University (Japan); Katsushi, Okuyama [Department of Restorative Dentistry, Graduate School of Dental Medicine Hokkaido University (Japan); Hiroko, Yamamoto [Graduate School of Dentistry, Osaka University (Japan); Hisanori, Komatsu [Department of Restorative Dentistry, Graduate School of Dental Medicine Hokkaido University (Japan); Masashi, Koka; Takahiro, Sato [Takasaki Advanced Radiation Research Institute, JAEA (Japan); Naoki, Hashimoto; Saiko, Oki; Chiharu, Kawamoto; Hidehiko, Sano [Department of Restorative Dentistry, Graduate School of Dental Medicine Hokkaido University (Japan)

    2015-04-01

    To prevent the formation of caries and reduce dentin hypersensitivity, sealing materials, either with or without fluoride, are generally applied on the tooth in clinical practice. Application of fluoride-free sealing materials results in the formation of an acid-resistant layer on the tooth surface. On the other hand, fluoride-containing sealing materials might not only form an acid-resistant layer but could possibly further provide fluoride to enhance remineralization and reduce demineralization. In this study, the demineralization prevention ability and fluorine uptake rate in human enamel of fluoride-containing sealing materials [“MS coats F” (MSF)] and fluoride-free sealing materials (“hybrid coats 2” [HI]) were evaluated using an automatic pH cycling system. Each material was applied to the original tooth surface, the cut surfaces were covered with sticky wax, and the automatic pH-cycling system simulated daily acid changes (pH 6.8–4.5) occurring in the oral cavity for 4 weeks. Caries progression was analyzed using transverse microradiography (TMR) taken pre and post the 4 weeks of pH cycling. The fluorine and calcium distributions in the carious lesion in each specimen were evaluated using the proton-induced gamma emission (PIGE) and proton-induced X-ray (PIXE) techniques, respectively. TMR analysis showed that both MSF and HI had a caries-preventing effect after 4 weeks of pH cycling. PIGE/PIXE analysis demonstrated that only MSF resulted in fluoride uptake in the enamel surface. Therefore, MSF can help to form an acid-resistant layer and provide fluoride to the enamel surface. The presence of fluoride on the enamel surface suggested that MSF could prevent demineralization, even if the acid-resistant layer was removed, in clinical settings. The data obtained using the PIGE and PIXE techniques are useful for understanding the benefits of the use of a fluoride-containing sealing material for preventing caries.

  9. Fluorine uptake into the human enamel surface from fluoride-containing sealing materials during cariogenic pH cycling

    International Nuclear Information System (INIS)

    Yasuhiro, Matsuda; Katsushi, Okuyama; Hiroko, Yamamoto; Hisanori, Komatsu; Masashi, Koka; Takahiro, Sato; Naoki, Hashimoto; Saiko, Oki; Chiharu, Kawamoto; Hidehiko, Sano

    2015-01-01

    To prevent the formation of caries and reduce dentin hypersensitivity, sealing materials, either with or without fluoride, are generally applied on the tooth in clinical practice. Application of fluoride-free sealing materials results in the formation of an acid-resistant layer on the tooth surface. On the other hand, fluoride-containing sealing materials might not only form an acid-resistant layer but could possibly further provide fluoride to enhance remineralization and reduce demineralization. In this study, the demineralization prevention ability and fluorine uptake rate in human enamel of fluoride-containing sealing materials [“MS coats F” (MSF)] and fluoride-free sealing materials (“hybrid coats 2” [HI]) were evaluated using an automatic pH cycling system. Each material was applied to the original tooth surface, the cut surfaces were covered with sticky wax, and the automatic pH-cycling system simulated daily acid changes (pH 6.8–4.5) occurring in the oral cavity for 4 weeks. Caries progression was analyzed using transverse microradiography (TMR) taken pre and post the 4 weeks of pH cycling. The fluorine and calcium distributions in the carious lesion in each specimen were evaluated using the proton-induced gamma emission (PIGE) and proton-induced X-ray (PIXE) techniques, respectively. TMR analysis showed that both MSF and HI had a caries-preventing effect after 4 weeks of pH cycling. PIGE/PIXE analysis demonstrated that only MSF resulted in fluoride uptake in the enamel surface. Therefore, MSF can help to form an acid-resistant layer and provide fluoride to the enamel surface. The presence of fluoride on the enamel surface suggested that MSF could prevent demineralization, even if the acid-resistant layer was removed, in clinical settings. The data obtained using the PIGE and PIXE techniques are useful for understanding the benefits of the use of a fluoride-containing sealing material for preventing caries

  10. Prevention of dental caries through the effective use of fluoride

    DEFF Research Database (Denmark)

    Petersen, Poul Erik

    2016-01-01

    Background: The World Health Organization (WHO) emphasizes that dental caries is a severe public health problem across the world. The current global and regional patterns of dental caries reflect distinct risk profiles of countries which relate to the structure of the society, living conditions......, lifestyles, and the existence of preventive oral health programmes. Research conducted in high income countries documents that systematic use of fluoride reduces the burden of dental caries; such research is scarce in low and middle income countries. Objectives: This article reviews the evidence on effective...... use of fluoride, highlights the public health approach to fluoridation, and clarifies how automatic fluoridation contributes to breaking social inequities in dental caries. Data collection: Scientific publications on fluoride administration stored in PubMed/Medline and caries data from the WHO...

  11. Community-oriented administration of fluoride for the prevention of dental caries

    DEFF Research Database (Denmark)

    Petersen, P E; Baez, R J; Lennon, M A

    2012-01-01

    Dental caries is the most prevalent chronic disease affecting human populations around the world. It is recognized that fluoride plays a significant role in dental caries reduction. Meanwhile, several low- and middle-income countries of Asia have not yet implemented systematic fluoride programs...... coverage. Participants acknowledged that automatic fluoridation through water, salt, and milk is the most effective and equitable strategy for the prevention of dental caries. Concerns were expressed that government-subsidized community fluoride prevention programs may face privatization. In addition...... need further dissemination. The meeting was co-sponsored by the World Health Organization, the International Association for Dental Research, and the World Dental Federation....

  12. Western Australian schools access to dentally optimal fluoridated water.

    Science.gov (United States)

    Desai, P; Kruger, E; Trolio, R; Tennant, M

    2015-03-01

    This study examined water fluoride levels at schools across Western Australia. The aim was to identify schools where levels of water fluoride appeared to be below dental health thresholds (0.5-1.0 mg/L) as recommended by the National Health and Medical Research Council (NHMRC). The objective is to provide health organizations with the knowledge for a more targeted approach to schools with greater risk of decay. Population data, school location, enrolment data and water quality data were integrated into geographic databases for analysis using Quantum GIS, Lisboa 1.8. The results indicated that 46% of school attendees in the northern half of Western Australia were at schools where there was the potential that the water was not dentally optimally fluoridated while in the southern half of Western Australia this was about 10%. Of these attendees (north and south), 45% were at primary school. Similarly, there was an association between socio-economic decile and proportion of school attendees in non-dentally optimally fluoridated schools. Lower deciles (i.e. poorer attendees) had a greater risk of being in schools outside dentally optimally fluoridated areas. This study clearly highlights areas where more prevention (and probably) treatment needs are present and provides a framework for targeted service planning. © 2015 Australian Dental Association.

  13. Effect of xylitol, sodium fluoride and triclosan containing mouth rinse on Streptococcus mutans

    Directory of Open Access Journals (Sweden)

    Priya Subramaniam

    2011-01-01

    Full Text Available Introduction : Prevention of dental caries is one of the main strategies in contemporary pediatric dental practice. Mouth rinses are widely used as an adjunct to maintain oral hygiene. It is important for these products to be effective and safe for regular use in children. Objective : The aim of the study was to investigate the efficacy of a newly introduced xylitol, sodium fluoride and triclosan containing mouth rinse in reducing levels of plaque Streptococcus mutans and to compare it with that of a 0.12% chlorhexidine mouth rinse. Materials and Methods : Thirty children were randomly divided into two groups of 15 children each. Group I (study group was given a mouth rinse containing xylitol (5%, sodium fluoride (0.05% and triclosan (0.03% and Group II (control group was given a chlorhexidine (0.12% mouth rinse. Both mouth rinses were alcohol free. Mouth rinsing was carried out twice daily, half an hour after breakfast and half an hour following dinner, for a period of 21 days under the supervision of the investigator. Results: In both groups, there was a significant reduction in the mean S. mutans count at the end of 21 days (P < 0.001. No significant difference was observed between the two mouth rinses. Conclusion: The use of a low fluoride-xylitol based mouth rinse appears to be a suitable choice for regular use in children.

  14. [Influence of the fluoride releasing dental materials on the bacterial flora of dental plaque].

    Science.gov (United States)

    Płuciennik, Małgorzata; Sakowska, Danuta; Krzemiński, Zbigniew; Piatowska, Danuta

    2008-01-01

    The assessment of influence of silver-free, fluor releasing dental materials on dental plaque bacteria quantity. 17 patients were included into the study. 51 restorations were placed following manufacturers recommendations. Following materials were used: conventional glassionomer Ketac-Molar ESPE, resin modified glassionomer Fuji II LC GC and fluor containing composite Charisma Heraeus Kulzer Class V restorations were placed in following teeth of upper and lower jaw: canines, first bicuspids, second bicuspids. Sound enamel was a control. After 10 weeks the 72 hours old dental plaque was collected from surface of restorations and control using sterile probe. Total amount of 68 dental plaques were investigated. Each plaque was placed on scaled and sterile aluminum foil. The moist weight of dental plaque was scaled. Dental plaque was moved into 7 ml 0.85% NaCl solution reduced by cystein chlorine hydrogen and disintegrated by ultrasounds (power:100 Watt, wave amplitude: 5 micorm). The suspension of dental plaque was serially diluted from 10(-4) to 10(-5) in sterile 0,85% NaCl solution, and seeded with amount of 0.1 ml on appropriate base. In dental plaque trials the amount of cariogenic bacteria was calculated--Streptococcus mutans, Streptococcus, Lactobacillus, Veillonella and Neisseria, and also total amount of aerobic and anaerobic bacteria was measured. Microbiologic studies were performed in Institute of Microbiology, Medical University, Łódź. Statistical analysis of collected data was accomplished. In 72 hours old dental plaques collected from the surfaces of Ketac -Molar, Fuji II LC, Charisma after 10 weeks since being placed into the class V cavity, results show no statistically significant differences in the amount of Streptococcus mutans, Streptococcus spp., Lactobacillus spp., Veillonella spp., Neisseria spp, in total amount of aerobic and anaerobic bacteria and in the quantity proportion of Streptococcus mutans versus Streptococcus spp. in comparison

  15. Health impact of supplying safe drinking water containing fluoride below permissible level on flourosis patients in a fluoride-endemic rural area of West Bengal.

    Science.gov (United States)

    Majumdar, Kunal Kanti

    2011-01-01

    The problem of high fluoride concentration in groundwater resources has become one of the most important toxicological and geo-environmental issues in India. Excessive fluoride in drinking water causes dental and skeletal fluorosis, which is encountered in endemic proportions in several parts of the world. World Health Organization (WHO) guideline value and the permissible limit of fluoride as per Bureau of Indian Standard (BIS) is 1.5 mg/L. About 20 states of India, including 43 blocks of seven districts of West Bengal, were identified as endemic for fluorosis and about 66 million people in these regions are at risk of fluoride contamination. Studies showed that withdrawal of sources identified for fluoride often leads reduction of fluoride in the body fluids (re-testing urine and serum after a week or 10 days) and results in the disappearance of non-skeletal fluorosis within a short duration of 10-15 days. To determine the prevalence of signs and symptoms of suspected dental, skeletal, and non-skeletal fluorosis, along with food habits, addictions, and use of fluoride containing toothpaste among participants taking water with fluoride concentration above the permissible limit, and to assess the changes in clinical manifestations of the above participants after they started consuming safe drinking water. A longitudinal intervention study was conducted in three villages in Rampurhat Block I of Birbhum district of West Bengal to assess the occurrence of various dental, skeletal, and non-skeletal manifestations of fluorosis, along with food habits, addictions, and use of fluoride containing toothpaste among the study population and the impact of taking safe water from the supplied domestic and community filters on these clinical manifestations. The impact was studied by follow-up examination of the participants for 5 months to determine the changes in clinical manifestations of the above participants after they started consuming safe drinking water from supplied

  16. Fluoride reactions with dental enamel following different forms of fluoride supply

    International Nuclear Information System (INIS)

    Hellstroem, I.; Ericsson, Y.

    1976-01-01

    The reactions with dental enamel of NaF as tablets dissolved in different beverages or supplied with NaCl, simulating domestic salt fluoridation, were studied in tests with enamel surfaces and enamel powder. It was confirmed that powdered enamel can react quite differently from enamel surfaces under certain conditions. Enamel surfaces took up much more fluoride (F) from orange juice than from water or milk, and neither the low pH nor the citrate content of the juice increased the formation of unstable CaF 2 in the enamel, as judged from a KOH leaching test. The F uptake by enamel surfaces from 0.25 mM NaF in 175 mM NaCl, corresponding to a dish prepared with salt containing 500 parts/10 6 F, was about 80 percent greater than from the same NaF concentration in water. This NaCl concentration did not increase the formation of CaF 2 in the enamel, as judged from the KOH test, while 350 mM NaCl caused a moderate increase. The investigations support the administration of NaF tablets with orange juice and the plans for domestic salt fluoridation. (author)

  17. In Vitro Inhibition of Enamel Demineralisation by Fluoride-releasing Restorative Materials and Dental Adhesives.

    Science.gov (United States)

    Dionysopoulos, Dimitrios; Koliniotou-Koumpia, Eugenia; Helvatzoglou-Antoniades, Maria; Kotsanos, Nikolaos

    2016-01-01

    To determine the ability of 5 contemporary fluoride-releasing restoratives and 3 fluoride-releasing adhesives to inhibit enamel demineralisation surrounding restorations, and the associations between inhibition and the levels of fluoride released from these materials. Five fluoride-releasing restoratives (Fuji IX GP, Ketac N100, Dyract Extra, Beautifil II and Wave) and 3 fluoride-releasing adhesives (Stae, Prime & Bond NT and Fluoro Bond II) were investigated. Eight disks of each material were prepared. Fluoride release was measured daily using a fluoride-ion-selective electrode for 15 days. Twenty-four cavities for each group were restored with a restorative and an adhesive. Specimens were subjected to thermal stress and stored for 30 days in saline solution. After a 15-day pH-cycling regimen, two 150-μm-thick sections were derived from each specimen. Enamel lesion depth was measured at 0, 100, and 200 μm from each restoration's margin via polarised light microscopy. Of the restoratives investigated, Fuji IX GP released the most fluoride. The fluoride-releasing restoratives tested exhibited shallower enamel lesions than did the control group at all distances tested (p < 0.05). Fuji IX GP yielded significantly lower enamel lesion depth than did the other experimental materials. The depths of enamel lesions did not differ significantly when comparing restoratives applied with a fluoride-releasing adhesive with those applied with a non-fluoride-releasing adhesive. The fluoride-releasing materials tested reduced enamel demineralisation but to different extents, depending on their levels of fluoride release. Fluoride-releasing adhesives did not influence enamel lesion formation.

  18. The effect of orthodontic bonding materials on dental plaque accumulation and composition in vitro.

    Science.gov (United States)

    Badawi, H; Evans, R D; Wilson, M; Ready, D; Noar, J H; Pratten, J

    2003-08-01

    The aim of this study was to investigate the accumulation and composition of microcosm dental plaque on different orthodontic bonding materials using an in vitro model. Microcosm plaques were grown on discs of a range of bonding materials in a constant depth film fermentor. The biofilms were derived from human saliva and supplied with artificial saliva as a source of nutrients. The number of viable bacteria in the biofilms was determined and the streptococci present were identified to species level. The results showed that there was no significant difference in bacterial accumulation between different bonding materials, however, biofilms grown on materials which were fluoride releasing, did not contain Streptococcus mutans. This in vitro study has shown that the use of fluoride-releasing bonding materials may support the growth of supragingival plaque, which does not contain S. mutans.

  19. Prevalence and extent of dental caries, dental fluorosis, and developmental enamel defects in Lithuanian teenage populations with different fluoride exposures

    DEFF Research Database (Denmark)

    Machiulskiene, Vita; Bælum, Vibeke; Fejerskov, Ole

    2009-01-01

    The aim of this study was to describe the pattern of dental caries, dental fluorosis, and developmental defects of non-fluoride origin in Lithuanian children born and raised in regions with 1.1 ppm (1.1 mg/l F) and 0.3 ppm (0.3 mg/l F) water fluoride levels, respectively. All permanent surfaces/t...... difference, 3.43). The results lend support to the hypothesis that the presence of fluoride in the oral environment promotes lesion arrest rather than inhibiting the initiation of new lesions......./teeth of 300 teenagers were examined for dental caries, dental fluorosis, and non-fluoride developmental defects. The caries prevalence of the study population was 100%. The mean number of decayed surfaces (DS) differed only slightly and statistically insignificantly between the '1.1 ppm fluoride' and '0.3 ppm...

  20. Fluoride loaded polymeric nanoparticles for dental delivery.

    Science.gov (United States)

    Nguyen, Sanko; Escudero, Carlos; Sediqi, Nadia; Smistad, Gro; Hiorth, Marianne

    2017-06-15

    The overall aim of the present paper was to develop fluoride loaded nanoparticles based on the biopolymers chitosan, pectin, and alginate, for use in dental delivery. First, the preparation of nanoparticles in the presence of sodium fluoride (NaF) as the active ingredient by ionic gelation was investigated followed by an evaluation of their drug entrapment and release properties. Chitosan formed stable, spherical, and monodisperse nanoparticles in the presence of NaF and tripolyphoshate as the crosslinker, whereas alginate and pectin were not able to form any definite nanostructures in similar conditions. The fluoride loading capacity was found to be 33-113ppm, and the entrapment efficiency 3.6-6.2% for chitosan nanoparticles prepared in 0.2-0.4% (w/w) NaF, respectively. A steady increase in the fluoride release was observed for chitosan nanoparticles prepared in 0.2% NaF both in pH5 and 7 until it reached a maximum at time point 4h and maintained at this level for at least 24h. Similar profiles were observed for formulations prepared in 0.4% NaF; however the fluoride was released at a higher level at pH5. The low concentration, but continuous delivery of fluoride from the chitosan nanoparticles, with possible expedited release in acidic environment, makes these formulations highly promising as dental delivery systems in the protection against caries development. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Water fluoridation for the prevention of dental caries.

    Science.gov (United States)

    Iheozor-Ejiofor, Zipporah; Worthington, Helen V; Walsh, Tanya; O'Malley, Lucy; Clarkson, Jan E; Macey, Richard; Alam, Rahul; Tugwell, Peter; Welch, Vivian; Glenny, Anne-Marie

    2015-06-18

    Dental caries is a major public health problem in most industrialised countries, affecting 60% to 90% of school children. Community water fluoridation was initiated in the USA in 1945 and is currently practised in about 25 countries around the world; health authorities consider it to be a key strategy for preventing dental caries. Given the continued interest in this topic from health professionals, policy makers and the public, it is important to update and maintain a systematic review that reflects contemporary evidence. To evaluate the effects of water fluoridation (artificial or natural) on the prevention of dental caries.To evaluate the effects of water fluoridation (artificial or natural) on dental fluorosis. We searched the following electronic databases: The Cochrane Oral Health Group's Trials Register (to 19 February 2015); The Cochrane Central Register of Controlled Trials (CENTRAL; Issue 1, 2015); MEDLINE via OVID (1946 to 19 February 2015); EMBASE via OVID (1980 to 19 February 2015); Proquest (to 19 February 2015); Web of Science Conference Proceedings (1990 to 19 February 2015); ZETOC Conference Proceedings (1993 to 19 February 2015). We searched the US National Institutes of Health Trials Registry (ClinicalTrials.gov) and the World Health Organization's WHO International Clinical Trials Registry Platform for ongoing trials. There were no restrictions on language of publication or publication status in the searches of the electronic databases. For caries data, we included only prospective studies with a concurrent control that compared at least two populations - one receiving fluoridated water and the other non-fluoridated water - with outcome(s) evaluated at at least two points in time. For the assessment of fluorosis, we included any type of study design, with concurrent control, that compared populations exposed to different water fluoride concentrations. We included populations of all ages that received fluoridated water (naturally or artificially

  2. Milk fluoridation for the prevention of dental caries

    Directory of Open Access Journals (Sweden)

    Jolán Bánóczy

    2013-11-01

    Full Text Available The aim of this review is to give an overview of 55 years experience of milk fluoridation and draw conclusions about the applicability of the method. Fluoridated milk was first investigated in the early 1950s, almost simultaneously in Switzerland, the USA and Japan. Stimulated by the favourable results obtained from these early studies, the establishment of The Borrow Dental Milk Foundation (subsequently The Borrow Foundation in England gave an excellent opportunity for further research, both clinical and non-clinical, and a productive collaboration with the World Health Organization which began in the early 1980s. Numerous peer-reviewed publications in international journals showed clearly the bioavailability of fluoride in various types of milk. Clinical trials were initiated in the 1980s – some of these can be classed as randomised controlled trials, while most of the clinical studies were community preventive programmes. Conclusion. These evaluations showed clearly that the optimal daily intake of fluoride in milk is effective in preventing dental caries. The amount of fluoride added to milk depends on background fluoride exposure and age of the children: commonly in the range 0.5 to 1.0 mg per day. An advantage of the method is that a precise amount of fluoride can be delivered under controlled conditions. The cost of milk fluoridation programmes is low, about € 2 to 3 per child per year. Fluoridation of milk can be recommended as a caries preventive measure where the fluoride concentration in drinking water is suboptimal, caries experience in children is significant, and there is an existing school milk programme.

  3. Milk fluoridation for the prevention of dental caries.

    Science.gov (United States)

    Bánóczy, Jolán; Rugg-Gunn, Andrew; Woodward, Margaret

    2013-11-01

    The aim of this review is to give an overview of 55 years experience of milk fluoridation and draw conclusions about the applicability of the method. Fluoridated milk was first investigated in the early 1950s, almost simultaneously in Switzerland, the USA and Japan. Stimulated by the favourable results obtained from these early studies, the establishment of The Borrow Dental Milk Foundation (subsequently The Borrow Foundation) in England gave an excellent opportunity for further research, both clinical and non-clinical, and a productive collaboration with the World Health Organization which began in the early 1980s. Numerous peer-reviewed publications in international journals showed clearly the bioavailability of fluoride in various types of milk. Clinical trials were initiated in the 1980s - some of these can be classed as randomised controlled trials, while most of the clinical studies were community preventive programmes. These evaluations showed clearly that the optimal daily intake of fluoride in milk is effective in preventing dental caries. The amount of fluoride added to milk depends on background fluoride exposure and age of the children: commonly in the range 0.5 to 1.0 mg per day. An advantage of the method is that a precise amount of fluoride can be delivered under controlled conditions. The cost of milk fluoridation programmes is low, about € 2 to 3 per child per year. Fluoridation of milk can be recommended as a caries preventive measure where the fluoride concentration in drinking water is suboptimal, caries experience in children is significant, and there is an existing school milk programme. Copyright © 2013 by Academy of Sciences and Arts of Bosnia and Herzegovina.

  4. Fluoride releasing and enamel demineralization around orthodontic brackets by fluoride-releasing composite containing nanoparticles.

    Science.gov (United States)

    Melo, Mary A S; Morais, Weslanny A; Passos, Vanara F; Lima, Juliana P M; Rodrigues, Lidiany K A

    2014-05-01

    Fluoride-containing materials have been suggested to control enamel demineralization around orthodontic brackets during the treatment with fixed appliances. The improvement of their properties has been made through innovations, such as the application of nanotechnology by incorporation of nanofillers. This in vitro study evaluated the capacity of fluoride releasing and enamel demineralization inhibition of fluoride-releasing nanofilled cement around orthodontic brackets using an artificial caries biofilm model. Forty bovine enamel discs were selected by evaluating surface microhardness and randomized into four groups (n = 10): non-fluoride-releasing microfilled composite, fluoride-releasing microfilled composite, resin-modified glass ionomer cement (RMGI), and fluoride-releasing nanofilled composite (FN). After brackets bonding in each disc, the specimens were subjected to a cariogenic challenge through a Streptococcus mutans biofilm model. After the experimental period, the biofilm formed around the brackets was collected for fluoride analysis and the mineral loss around the brackets was determined by integrated demineralization via cross-sectional microhardness measurement at 20 and 70 μm from the bracket margin. Additionally, samples of each group were subjected to energy-dispersive X-ray spectroscopy (EDX) analysis examined under a scanning electron microscopy (SEM). ANOVA followed by Tukey test were applied for fluoride concentration and mineral loss data, respectively. At both distances, only RMGI statistically differed from the other groups presenting the lowest demineralization, although there was a trend to a lower demineralization of enamel around brackets in FN group. Similar condition was found to fluoride concentration and EDX/SEM analysis. Under the cariogenic exposure condition of this study, the fluoride-releasing nanofilled material had similar performance to fluoride-releasing microfilled materials. The presence of nanofillers in the fluoride

  5. Trend Analysis of Studies on Water Fluoridation Related to Dental Caries in PubMed.

    Science.gov (United States)

    Oh, Hyo-Jung; Choi, Hyeon-Mi; Kim, Chonghyuck; Jeon, Jae-Gyu

    2018-04-04

    Water fluoridation has been cited as one of the top 10 public health achievements of the 20th century. Herein, we analyzed water fluoridation articles related to dental caries published in PubMed between 1950 and 2016 using informetrics and linguistic methods to investigate trends in the studies. To this aim, queries such as "dental caries and (water fluoridation or fluoridated water)," "dental caries and (fluoride or fluoridation)," and "dental caries" were submitted to PubMed to retrieve information about articles on water fluoridation within the area of dental caries and fluoride - their titles, abstracts, publication dates, author affiliations, and publication journals. This article information was then collected by an automatic web crawler and examined through informetrics and linguistic analyses. It was found that the number of articles concerned with water fluoridation and dental caries was 3,381 and declined over time after 1970. The articles were published by 750 journals - most notably, Community Dentistry and Oral Epidemiology and Caries Research. With regard to the geographic distribution of the authors, Europe and North America, especially the USA and UK, accounted for 59.9% of the articles published during the years 1987 to 2015, though there was a sharp increase in the number of authors in Oceania and Asia in recent years. In the titles and abstracts of the articles, "community" and "fluorosis" were mentioned more frequently than the other key terms selected in this study, regardless of the period examined. Our findings may allow one to assess how the research on water fluoridation has evolved over the past several decades. © 2018 S. Karger AG, Basel.

  6. Cytotoxic effects of glass ionomer cements on human dental pulp stem cells correlate with fluoride release.

    Science.gov (United States)

    Kanjevac, Tatjana; Milovanovic, Marija; Volarevic, Vladislav; Lukic, Miodrag L; Arsenijevic, Nebojsa; Markovic, Dejan; Zdravkovic, Nebojsa; Tesic, Zivoslav; Lukic, Aleksandra

    2012-01-01

    Glass ionomer cements (GICs) are commonly used as restorative materials. Responses to GICs differ among cell types and it is therefore of importance to thoroughly investigate the influence of these restorative materials on pulp stem cells that are potential source for dental tissue regeneration. Eight biomaterials were tested: Fuji I, Fuji II, Fuji VIII, Fuji IX, Fuji Plus, Fuji Triage, Vitrebond and Composit. We compared their cytotoxic activity on human dental pulp stem cells (DPSC) and correlated this activity with the content of Fluoride, Aluminium and Strontium ions in their eluates. Elution samples of biomaterials were prepared in sterile tissue culture medium and the medium was tested for toxicity by an assay of cell survival/proliferation (MTT test) and apoptosis (Annexin V FITC Detection Kit). Concentrations of Fluoride, Aluminium and Strontium ions were tested by appropriate methods in the same eluates. Cell survival ranged between 79.62% (Fuji Triage) to 1.5% (Fuji Plus) and most dead DPSCs were in the stage of late apoptosis. Fluoride release correlated with cytotoxicity of GICs, while Aluminium and Strontium ions, present in significant amount in eluates of tested GICs did not. Fuji Plus, Vitrebond and Fuji VIII, which released fluoride in higher quantities than other GICs, were highly toxic to human DPSCs. Opposite, low levels of released fluoride correlated to low cytotoxic effect of Composit, Fuji I and Fuji Triage.

  7. Fluoride in dental biofilm and saliva

    DEFF Research Database (Denmark)

    Larsen, Line Staun

    Dette ph.d.-projekt bidrager med ny viden om fordelingen af fluorid i dental biofilm og saliva. For at udforske koncentrationen af fluorid i naturlig (in vivo) biofilmvæske, biofilmsediment og i saliva, blev der udført to meget forskellige kliniske studier. Resultaterne fra tværsnitsstudiet (Studie...... I), hos en stor gruppe mennesker (n=42) der konsulterede en tandklinik for behandling, bekræfter tidligere viden, at der findes en naturlig biologisk variation i fluoridkoncentrationerne i biofilm fra forskellige intra-orale regioner samt mellem biofilmvæske, biofilmsediment og saliva...... fluoridkoncentrationer i underkæbefronten, intermediære koncentrationer i alle tre overkæberegioner og de laveste koncentrationer i underkæbemolarregionerne. Begge studier viser at biofilmsedimentet indeholder størstedelen af fluorid i biofilm. Set i et bredere perspektiv viser fundene at der er et omvendt forhold...

  8. Effect of Fluoride Mouthrinse and Toothpaste on Number of Streptococcal Colony Forming Units of Dental Plaque

    Directory of Open Access Journals (Sweden)

    SE Jabbarifar

    2005-11-01

    Full Text Available Background: Frequent topical fluoride therapy through toothpaste, mouthrinse, professional gels and solutions causes decrease in incidence, pause and repair of dental caries in the enamel. These mechanisms are done through penetration of fluoride ions (F- and their replacement with hydroxyl ions (OH- of hydroxyappatite of enamel, interfere with microbial metabolism of dental plaque and bacteriostatic effect on some cariogenic bacterial strains such as streptococci. The aim of this study was to examine the effect of fluoride mouthrinse and toothpaste on the number of streptococcal colony forming units of dental plaque. Methods: 62 children with 6-7 years old were put in two groups. Samples of dental plaque from each group were collected both before and after use of the fluoride mouthrinse and or toothpaste. The samples were cultured on blood agar to find the number of streptococcal colony forming units (CFU. The mean colony forming unit was compared inter and intra groups before and after application of Fluoride products. Results: The streptococcal CFU of dental plaque before and after use of the mouthrinse and toothpaste respectively was (1240±1367, 1253±1341.5 and (551±716, 898±1151. Statistically, the streptococcal CFU in each group before and after use of the toothpaste and mouthrinse was significantly different. Conclusion: The findings of this study indicated that the fluoride toothpaste and mouthrinse reduce number of streptococcal colony forming units of dental plaque. Also this reduction was not depended on level of (F- Ions, sort of vehicle of fluoride and frequent application of the fluoride mouthrinse and toothpaste. Keywords: fluoride mouthrinse, fluoride toothpaste, colony forming unit (CFU, streptococcus

  9. Decontamination of soils and materials containing medium-fired PuO{sub 2} using inhibited fluorides with polymer filtration technology

    Energy Technology Data Exchange (ETDEWEB)

    Temer, D.J.; Villarreal, R.; Smith, B.F. [Los Alamos National Lab., NM (United States)

    1997-10-01

    The decontamination of soils and/or materials from medium-fired plutonium oxide (PuO{sub 2}) with an effective and efficient decontamination agent that will not significantly dissolve the matrix requires a new and innovative technology. After testing several decontamination agents and solutions for dissolution of medium-fired PuO{sub 2}, the most successful decontamination solutions were fluoride compounds, which were effective in breaking the Pu-oxide bond but would not extensively dissolve soil constituents and other materials. The fluoride compounds, tetra fluoboric acid (HBF{sub 4}) and hydrofluorosilicic acid (H{sub 2}F{sub 6}Si), were effective in dissolving medium-fired PuO{sub 2}, and did not seem to have the potential to dissolve the matrix. In both compounds, the fluoride atom is attached to a boron or silicon atom that inhibits the reactivity of the fluoride towards other compounds or materials containing atoms less attracted to the fluoride atom in an acid solution. Because of this inhibition of the reactivity of the fluoride ion, these compounds are termed inhibited fluoride compounds or agents. Both inhibited fluorides studied effectively dissolved medium-fired PuO{sub 2} but exhibited a tendency to not attack stainless steel or soil. The basis for selecting inhibited fluorides was confirmed during leaching tests of medium-fired PuO{sub 2} spiked into soil taken from the Idaho National Engineering Laboratory (INEL). When dissolved in dilute HNO{sub 3}, HCl, or HBr, both inhibited fluoride compounds were effective at solubilizing the medium-fired PuO{sub 2} from spiked INEL soil.

  10. Combinatorial Effects of Arginine and Fluoride on Oral Bacteria

    OpenAIRE

    Zheng, X.; Cheng, X.; Wang, L.; Qiu, W.; Wang, S.; Zhou, Y.; Li, M.; Li, Y.; Cheng, L.; Li, J.; Zhou, X.; Xu, X.

    2015-01-01

    Dental caries is closely associated with the microbial disequilibrium between acidogenic/aciduric pathogens and alkali-generating commensal residents within the dental plaque. Fluoride is a widely used anticaries agent, which promotes tooth hard-tissue remineralization and suppresses bacterial activities. Recent clinical trials have shown that oral hygiene products containing both fluoride and arginine possess a greater anticaries effect compared with those containing fluoride alone, indicati...

  11. The differences in healthcare utilization for dental caries based on the implementation of water fluoridation in South Korea.

    Science.gov (United States)

    Cho, Myung-Soo; Han, Kyu-Tae; Park, Sohee; Moon, Ki Tae; Park, Eun-Cheol

    2016-11-08

    There were some debates about the water fluoridation program in South Korea, even if the program had generally substantial effectiveness. Because the out-of-pocket expenditures for dental care were higher in South Korea than in other countries, an efficient solution was needed. Therefore, we examined the relationship between the implementation of water fluoridation and the utilization of dental care. We used the National Health Insurance Service National Sample Cohort. In this study, data finally included 472,250 patients who were newly diagnosed with dental caries during 2003-2013. We performed survival analysis using cox proportional hazard model, negative binomial-regression, and regression analyses using generalized estimating equation models. There were 48.49 % outpatient dental care visit during study period. Individuals with water fluoridation had a lower risk of dental care visits (HR = 0.949, 95 % CI = 0.928-0.971). Among the individuals who experienced a dental care visit, those with water fluoridation program had a lower number of dental care visits (β = -0.029), and the period of water fluoridation had an inverse association with the dental care expenditures. The implementation of water fluoridation programs and these periods are associated with reducing the utilization of dental health care. Considering these positive impacts, healthcare professionals must consider preventive strategies for activating water fluoridation programs, such as changes in public perception and relations, for the effective management of dental care in South Korea.

  12. Exposure to High Fluoride Drinking Water and Risk of Dental Fluorosis in Estonia

    Directory of Open Access Journals (Sweden)

    Ene Indermitte

    2009-02-01

    Full Text Available The purpose of this study was to assess exposure to drinking water fluoride and evaluate the risk of dental fluorosis among the Estonian population. The study covered all 15 counties in Estonia and 93.7% of population that has access to public water supplies. In Estonia groundwater is the main source for public water supply systems in most towns and rural settlements. The content of natural fluoride in water ranges from 0.01 to 7.20 mg/L. The exposure to different fluoride levels was assessed by linking data from previous studies on drinking water quality with databases of the Health Protection Inspectorate on water suppliers and the number of water consumers in water supply systems. Exposure assessment showed that 4% of the study population had excessive exposure to fluoride, mainly in small public water supplies in western and central Estonia, where the Silurian-Ordovician aquifer system is the only source of drinking water. There is a strong correlation between natural fluoride levels and the prevalence of dental fluorosis. Risk of dental fluorosis was calculated to different fluoride exposure levels over 1.5 mg/L.

  13. Antibacterial Properties of Calcium Fluoride-Based Composite Materials: In Vitro Study

    Science.gov (United States)

    Zarzycka, Beata; Grzegorczyk, Janina; Sokołowski, Krzysztof; Półtorak, Konrad; Sokołowski, Jerzy

    2016-01-01

    The aim of the study was to evaluate antibacterial activity of composite materials modified with calcium fluoride against cariogenic bacteria S. mutans and L. acidophilus. One commercially available conventional light-curing composite material containing fluoride ions (F2) and two commercially available flowable light-curing composite materials (Flow Art and X-Flow) modified with 1.5, 2.5, and 5.0 wt% anhydrous calcium fluoride addition were used in the study. Composite material samples were incubated in 0.95% NaCl at 35°C for 3 days; then dilution series of S. mutans and L. acidophilus strains were made from the eluates. Bacteria dilutions were cultivated on media afterwards. Colony-forming unit per 1 mL of solution (CFU/mL) was calculated. Composite materials modified with calcium fluoride highly reduced (p composite materials containing fluoride compounds. The greatest reduction in bacteria growth was observed for composite materials modified with 1.5% wt. CaF2. All three tested composite materials showed statistically greater antibacterial activity against L. acidophilus than against S. mutans. PMID:28053976

  14. The effect of a fluoride dentifrice containing an anticalculus agent on dental caries in children.

    Science.gov (United States)

    Lu, K H; Yen, D J; Zacherl, W A; Ruhlman, C D; Sturzenberger, O P; Lehnhoff, R W

    1985-01-01

    In this double-blind caries study, 1160 Taiwanese children (ages 8-15) completed a program using a test dentifrice containing 1.243 percent sodium fluoride and soluble pyrophosphates, or a control dentifrice without these agents. The average reduction of new carious tooth surfaces was 39 percent with the sodium fluoride dentifrice.

  15. Artificial caries formation around fluoride-releasing restorations in roots.

    Science.gov (United States)

    Dionysopoulos, P; Kotsanos, N; Papadogiannis, Y; Konstantinidis, A

    1998-11-01

    Secondary caries is one of the most important factors leading to replacement of dental restorations. This investigation assessed the capacity of fluoride-releasing restorative materials to resist caries in vitro when used in roots. Class 5 cavities were prepared in the buccal and lingual surfaces of 30 extracted premolars. The six materials used were: glass-ionomer cement (Fuji), glass-ionomer cement with silver particles added (Ketac-silver), fluoride-containing composite resin (Tetric), composite resin (Silux plus), fluoride-containing amalgam (Fluor-Alloy) and high-copper amalgam (Dispersalloy). After 5 weeks in an acid gel for caries-like lesion formation, the teeth were sectioned longitudinally and examined with polarized light. The results showed that repair with glass-ionomer materials of a carious lesion may be of great importance in the prevention of secondary caries around the restorations in roots.

  16. Association between Urine Fluoride and Dental Fluorosis as a Toxicity Factor in a Rural Community in the State of San Luis Potosi

    Directory of Open Access Journals (Sweden)

    Lizet Jarquín-Yañez

    2015-01-01

    Full Text Available Objective. The aim of this study is to investigate urine fluoride concentration as a toxicity factor in a rural community in the state of San Luis Potosi, Mexico. Materials and Methods. A sample of 111 children exposed to high concentrations of fluoride in drinking water (4.13 mg/L was evaluated. Fluoride exposure was determined by measuring urine fluoride concentration using the potentiometric method with an ion selective electrode. The diagnosis of dental fluorosis was performed by clinical examination, and the severity of damage was determined using Dean’s index and the Thylstrup-Fejerskov (TF index. Results. The range of exposure in the study population, evaluated through the fluoride content in urine, was 1.1 to 5.9 mg/L, with a mean of 3.14 ± 1.09 mg/L. Dental fluorosis was present in all subjects, of which 95% had severe cases. Higher urine fluoride levels and greater degrees of severity occurred in older children. Conclusions. The results show that dental fluorosis was determined by the presence of fluoride exposure finding a high positive correlation between the severity of fluorosis and urine fluoride concentration and the years of exposure suggested a cumulative effect.

  17. Grout formulation for disposal of low-level and hazardous waste streams containing fluoride

    Science.gov (United States)

    McDaniel, E.W.; Sams, T.L.; Tallent, O.K.

    1987-06-02

    A composition and related process for disposal of hazardous waste streams containing fluoride in cement-based materials is disclosed. the presence of fluoride in cement-based materials is disclosed. The presence of fluoride in waste materials acts as a set retarder and as a result, prevents cement-based grouts from setting. This problem is overcome by the present invention wherein calcium hydroxide is incorporated into the dry-solid portion of the grout mix. The calcium hydroxide renders the fluoride insoluble, allowing the grout to set up and immobilize all hazardous constituents of concern. 4 tabs.

  18. Effective use of fluorides for the prevention of dental caries in the 21st century

    DEFF Research Database (Denmark)

    Petersen, Poul Erik; Lennon, Michael A

    2004-01-01

    Despite great improvements in the oral health of populations across the world, problems still persist particularly among poor and disadvantaged groups in both developed and developing countries. According to the World Oral Health Report 2003, dental caries remains a major public health problem...... in most industrialized countries, affecting 60-90% of schoolchildren and the vast majority of adults. Although it appears that dental caries is less common and less severe in developing countries of Africa, it is anticipated that the incidence of caries will increase in several countries of that continent......, due to changing living conditions and dietary habits, and inadequate exposure to fluorides. Research on the oral health effects of fluoride started around 100 years ago; the focus has been on the link between water and fluorides and dental caries and fluorosis, topical fluoride applications, fluoride...

  19. The Impact of Selected Fluoridated Toothpastes on Dental Erosion in Profilometric Measurement.

    Science.gov (United States)

    Fita, Katarzyna; Kaczmarek, Urszula

    2016-01-01

    Some fluoridated toothpastes, available commercially, are described to have a protective effect against dental erosion. To evaluate the influence of the selected marketed toothpastes on the human enamel exposed to acid beverages. Enamel specimens from extracted human teeth were prepared (n = 40). Specimens were randomly divided into 10 experimental groups, 4 specimens each, which were subjected to acid challenge for 10 min using orange juice (pH 3.79) or Pepsi Cola (pH 2.58) and then immersed for 2 min into a slurry of five marketed toothpastes with distilled water (1 : 3 w/w). The tested toothpastes contained 1450 or 5000 ppm fluoride, CPP-ACP with 900 ppm fluoride, 1450 ppm fluoride with potassium nitrate 5%, all of them as sodium fluoride, and 700 ppm fluoride as amine and sodium fluoride with 3500 ppm SnCl2. Enamel roughness (Ra parameter) by contact profilometer at baseline and after exposure onto soft drinks and slurry was measured. Exposure to both beverages caused a similar increase of enamel surface roughness. After the specimens immersion into slurries of toothpastes with 1450 or 5000 ppm fluoride, 1450 ppm fluoride with potassium nitrate 5% and CPP-ACP with 900 ppm fluoride the significant decrease of Ra values were found, reaching the baseline values. However, toothpaste with 700 ppm fluoride and 3500 ppm SnCl2 did not cause any fall in Ra value, probably due to other mechanism of action. Within the limitation of the study we can conclude that the sodium fluoride toothpastes are able to restore the surface profile of enamel exposed shortly to acidic soft drinks.

  20. Water fluoridation and the association of sugar-sweetened beverage consumption and dental caries in Australian children.

    Science.gov (United States)

    Armfield, Jason M; Spencer, A John; Roberts-Thomson, Kaye F; Plastow, Katrina

    2013-03-01

    We examined demographic and socioeconomic differences in the consumption of sugar-sweetened beverages (SSBs), its association with dental caries in children, and whether exposure to water fluoridation modifies this association. In a cross-sectional study, we used a stratified, clustered sampling design to obtain information on 16 508 children aged 5 to 16 years enrolled in Australian school dental services in 2002 to 2005. Dental staff assessed dental caries, and parents completed a questionnaire about their child's residential history, sources of drinking water, toothbrushing frequency, socioeconomic status (SES), and SSB consumption. Children who brushed their teeth less often and were older, male, of low SES, from rural or remote areas consumed significantly more SSBs. Caries was significantly associated with greater SSB consumption after controlling for potential confounders. Finally, greater exposure to fluoridated water significantly reduced the association between children's SSB consumption and dental caries. Consumption of SSBs should be considered a major risk factor for dental caries. However, increased exposure to fluoridated public water helped ameliorate the association between SSB consumption and dental decay. These results reconfirm the benefits of community water fluoridation for oral health.

  1. Association between Urine Fluoride and Dental Fluorosis as a Toxicity Factor in a Rural Community in the State of San Luis Potosi

    OpenAIRE

    Jarquín-Yañez, Lizet; Mejía-Saavedra, José de Jesús; Molina-Frechero, Nelly; Gaona, Enrique; Rocha-Amador, Diana Olivia; López-Guzmán, Olga Dania; Bologna-Molina, Ronell

    2015-01-01

    Objective. The aim of this study is to investigate urine fluoride concentration as a toxicity factor in a rural community in the state of San Luis Potosi, Mexico. Materials and Methods. A sample of 111 children exposed to high concentrations of fluoride in drinking water (4.13?mg/L) was evaluated. Fluoride exposure was determined by measuring urine fluoride concentration using the potentiometric method with an ion selective electrode. The diagnosis of dental fluorosis was performed by clinica...

  2. Fluoride Increase in Saliva and Dental Biofilm due to a Meal Prepared with Fluoridated Water or Salt: A Crossover Clinical Study.

    Science.gov (United States)

    Lima, Carolina V; Tenuta, Livia M A; Cury, Jaime A

    2018-06-07

    Knowledge about fluoride delivery to oral fluids from foods cooked with fluoridated water and salt is scarce, and no study has evaluated fluoride concentrations in saliva or biofilm during meal consumption. In this randomized double-blind crossover study, 12 volunteers ingested meals (rice, beans, meat, and legumes) prepared with nonfluoridated water and salt (control group), fluoridated water (0.70 mg F/L; water group), and fluoridated salt (183.7 mg F/kg; salt group). Whole saliva was collected before meal ingestion, during mastication, and up to 2 h after meal ingestion. Dental biofilm was collected before and immediately after meal ingestion. Fluoride concentrations in saliva and dental biofilm were determined by an ion-specific electrode. The mean (±standard deviation; n = 4) fluoride concentrations in meals prepared for the control, water, and salt groups were 0.039 ± 0.01, 0.43 ± 0.04, and 1.71 ± 0.32 μg F/g, respectively. The three groups had significantly different fluoride concentrations in saliva collected during mastication (p water > control). The fluoride concentration in saliva returned to baseline 30 min after meal ingestion in the water group but remained high for up to 2 h in the salt group (p = 0.002). The fluoride concentration in biofilm fluid differed only between the salt and control groups (p = 0.008). The mastication of foods cooked with fluoridated water and salt increases fluoride concentrations in oral fluids and may contribute to the local effect of these community-based fluoride interventions on caries control. © 2018 S. Karger AG, Basel.

  3. Acute toxicity of ingested fluoride.

    Science.gov (United States)

    Whitford, Gary Milton

    2011-01-01

    This chapter discusses the characteristics and treatment of acute fluoride toxicity as well as the most common sources of overexposure, the doses that cause acute toxicity, and factors that can influence the clinical outcome. Cases of serious systemic toxicity and fatalities due to acute exposures are now rare, but overexposures causing toxic signs and symptoms are not. The clinical course of systemic toxicity from ingested fluoride begins with gastric signs and symptoms, and can develop with alarming rapidity. Treatment involves minimizing absorption by administering a solution containing calcium, monitoring and managing plasma calcium and potassium concentrations, acid-base status, and supporting vital functions. Approximately 30,000 calls to US poison control centers concerning acute exposures in children are made each year, most of which involve temporary gastrointestinal effects, but others require medical treatment. The most common sources of acute overexposures today are dental products - particularly dentifrices because of their relatively high fluoride concentrations, pleasant flavors, and their presence in non-secure locations in most homes. For example, ingestion of only 1.8 ounces of a standard fluoridated dentifrice (900-1,100 mg/kg) by a 10-kg child delivers enough fluoride to reach the 'probably toxic dose' (5 mg/kg body weight). Factors that may influence the clinical course of an overexposure include the chemical compound (e.g. NaF, MFP, etc.), the age and acid-base status of the individual, and the elapsed time between exposure and the initiation of treatment. While fluoride has well-established beneficial dental effects and cases of serious toxicity are now rare, the potential for toxicity requires that fluoride-containing materials be handled and stored with the respect they deserve. Copyright © 2011 S. Karger AG, Basel.

  4. Assessment of Fluoride Level in Groundwater and Prevalence of Dental Fluorosis in Didwana Block of Nagaur District, Central Rajasthan, India

    Directory of Open Access Journals (Sweden)

    M Arif

    2013-10-01

    Full Text Available Background: In India, for the high concentration of fluoride in groundwater, people are at risk of dental fluorosis. The problem is common in various states of India. The condition in Rajasthan is worse where all districts have such a problem. Objective: To study the fluoride concentration in groundwater and prevalence of dental fluorosis in Didwana block of Nagaur district, Central Rajasthan, India. Methods: The fluoride concentration in water of 54 villages was measured electrochemically, using fluoride ion selective electrode. Dental fluorosis was assessed in 1136 people residing in study area by Dean's classification for dental fluorosis. Results: The fluoride concentration in groundwater in studied sites ranged from 0.5 to 8.5 mg/L. The concentration of fluoride was more than the maximum permissible limit set by WHO and Bureau of Indian Standards (1 mg/L in 48 groundwater sources. Of 1136 people studied, 788 (69.4%; 95% CI: 66.7%–72.1% had dental fluorosis—252 had mild and 74 had severe dental fluorosis. Conclusion: High level of fluoride in drinking water of Didwana block of Nagaur district, Central Rajasthan, India, causes dental fluorosis in most people in the region and is an important health problem that needs prompt attention.

  5. Effects of fluoride and epigallocatechin gallate on soft-drink-induced dental erosion of enamel and root dentin

    Directory of Open Access Journals (Sweden)

    Yin-Lin Wang

    2018-04-01

    Full Text Available Background/Purpose: Fluoride and epigallocatechin gallate (EGCG have been proven to prevent dental caries. The purpose of this study was to evaluate the effects of fluoride and EGCG on soft-drink-induced dental erosion in vitro. Methods: Forty enamel and dentin specimens were prepared from extracted human teeth. The specimens were divided into 4 groups and treated separately with distilled water (as control, 0.5 M sodium fluoride (NF, 400 μM EGCG (EG, and a solution containing 0.5 M NaF and 400 μM EGCG (FG. Cyclic erosive treatment was performed according to the experimental procedures. The specimens were analyzed using laser scanning confocal microscopy, scanning electron microscopy, and a microhardness tester. The data were analyzed using ANOVA and Bonferroni's post hoc test. The significance level was set at 5%. Results: The amount of substance loss was lower in the NF and EG groups than in the control group (p < 0.05. The erosion-caused substance loss was more pronounced in the dentin than in the enamel specimens. Surface microhardness loss was lower in the NF and EG groups than in the control group (p < 0.05. The diameter of the dentinal tubule was wider in the control group than in the NF and EG groups (p < 0.05. No combined effects were observed in the FG group. Conclusion: Both fluoride and EGCG are effective in preventing soft-drink-induced erosion compared with the control group. Fluoride and EGCG may interfere with each other. The mechanisms of the anti-erosive effect need to be explored in the future. Keywords: Dental erosion, Fluoride, Epigallocatechin gallate, Soft drinks, Laser scanning confocal microscopy

  6. Effect of various rinsing protocols after use of amine fluoride/stannous fluoride toothpaste on the bacterial composition of dental plaque

    NARCIS (Netherlands)

    van Loveren, C.; Gerardu, V.A.M.; Sissons, C.H.; van Bekkum, M.; ten Cate, J.M.

    2009-01-01

    This clinical study evaluated the effect of different oral hygiene protocols on the bacterial composition of dental plaque. After a 2-week period of using fluoride-free toothpaste, 30 participants followed three 1-week experimental protocols, each followed by 2-week fluoride-free washout periods in

  7. The relationship between dental caries and dental fluorosis in areas with moderate- and high-fluoride drinking water in Ethiopia.

    Science.gov (United States)

    Wondwossen, Fantaye; Astrøm, Anne Nordrehaug; Bjorvatn, Kjell; Bårdsen, Asgeir

    2004-10-01

    The aim of the study is to assess the relationship between caries and dental fluorosis in Ethiopian children living in Rift Valley areas known for endemic fluorosis. A total of 306 children (12-15 years old), selected from areas with moderate (0.3-2.2 mg/l), or high (10-14 mg/l) fluoride concentration in the drinking water were interviewed and examined for caries and dental fluorosis. Scorings were recorded according to the DMF system, and the Thylstrup-Fejerskov (TF) Index. Prevalence of dental fluorosis (TF-score > or = 1) was 91.8% (moderate area) and 100% (high-fluoride area). The corresponding caries prevalence and mean DMFT in the areas were 45.3% versus 61.6%, and 1.2 versus 1.8, respectively. Age and severity of dental fluorosis were found to be independent predictors for DMFT > or = 1. When compared with 12-year olds with TF-scores 0-4, odds ratios were 3.0 (95% CI 1.6-5.7) and 2.0 (95% CI 1.2-3.2) if TF-scores were > or = 5 and age 13-15 years, respectively. A positive relationship between caries and fluorosis was observed across tooth types in both areas. The percentage of children with DMFT > or = 1 was highest in groups with TF-score > or = 5 in the second molar, followed by the first molar. The present findings indicate that the second molar is the tooth most severely affected by dental fluorosis and dental caries. Dental caries increased with increasing severity of dental fluorosis, both in moderate- and high-fluoride areas. Thus, a positive relationship between dental caries and dental fluorosis was observed across various tooth types, in both areas. Copyright Blackwell Munksgaard, 2004

  8. FLUORIDE TOXICITY – A HARSH REALITY

    OpenAIRE

    Bandlapalli Pavani; Mandava Ragini; David Banji; Otilia J F Banji; N Gouri Pratusha

    2011-01-01

    There are many incidents of fluoride toxicity whether it is acute or chronic. Fluoride toxicity is an environmental hazard which arises from the upper layers of geological crust and is dissolved in water. Prolonged drinking of such water causes chronic fluoride toxicity. Use of fluoride containing compounds for various purposes such as dental products, metal, glass, refrigerator and chemical industries act as a source of fluoride poisoning and increase the risk of toxicity. This review reflec...

  9. Urinary fluoride excretion after application of fluoride varnish and use of fluoride toothpaste in young children

    DEFF Research Database (Denmark)

    Lockner, Frida; Twetman, Svante; Stecksén-Blicks, Christina

    2017-01-01

    BACKGROUND: The efficacy and safety of combined use of topical fluoride products are essential issues that must be monitored. AIM: To assess urinary excretion of fluoride after application of two different dental varnishes containing 2.26% fluoride in 3- to 4-year-old children and to compare...... the levels with and without parallel use of fluoride toothpaste. DESIGN: Fifteen healthy children were enrolled to a randomized crossover trial that was performed in two parts: Part I with twice-daily tooth brushing with fluoride toothpaste and Part II with twice-daily brushing with a non-fluoride toothpaste....... After a 1-week run-in period, 0.1 mL of the two fluoride varnishes (Duraphat and Profluorid Varnish) was topically applied in a randomized order. Baseline and experimental urine was collected during 6-h periods. The fluoride content was determined with an ion-sensitive electrode. RESULTS...

  10. Comparative effect of fluoride, essential oil and chlorhexidine mouth rinses on dental plaque and gingivitis in patients with and without dental caries: a randomized controlled trial.

    Science.gov (United States)

    Charugundla, B R; Anjum, S; Mocherla, M

    2015-05-01

    The objective of this study was to compare the effectiveness of fluoride, essential oil (EO) and chlorhexidine (CHX)-containing mouth rinses on dental plaque and gingivitis and to compare their relative efficacy in patients with and without dental caries. A randomized, controlled, double- blind, crossover clinical trial was conducted for a period of 8 weeks. Thiry-six qualifying subjects, aged 12-44 years, were included in the study. Subjects were divided into caries and caries-free groups and were randomly assigned to one of the following mouth rinse groups: fluoride; EO; CHX and saline as negative control. Subjects used their respective mouth rinse for a period of 7-days each with 1-week wash-out periods. Primary efficacy variables were Quigley-Hein plaque index (PI) and Loe and Silness gingival index. Fluoride and CHX mouth rinses showed significant reduction in plaque after use of mouth rinses (P gingivitis (P > 0.05). Further significant differences were found in reducing plaque and gingivitis in caries-free subjects in comparison to those with caries (P gingivitis especially in caries-free subjects in comparison to those with caries, and amongst the three, fluoride and CHX proved to be more effective than EO mouth rinse. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  11. Oral fluoride reservoirs and the prevention of dental caries.

    Science.gov (United States)

    Vogel, Gerald Lee

    2011-01-01

    Current models for increasing the anti-caries effects of fluoride (F) agents emphasize the importance of maintaining a cariostatic concentration of F in oral fluids. The concentration of F in oral fluids is maintained by the release of this ion from bioavailable reservoirs on the teeth, oral mucosa and - most importantly, because of its association with the caries process - dental plaque. Oral F reservoirs appear to be of two types: (1) mineral reservoirs, in particular calcium fluoride or phosphate-contaminated 'calcium-fluoride-like' deposits; (2) biological reservoirs, in particular (with regard to dental plaque) F held to bacteria or bacterial fragments via calcium-fluoride bonds. The fact that all these reservoirs are mediated by calcium implies that their formation is limited by the low concentration of calcium in oral fluids. By using novel procedures which overcome this limitation, the formation of these F reservoirs after topical F application can be greatly increased. Although these increases are associated with substantive increases in salivary and plaque fluid F, and hence a potential increase in cariostatic effect, it is unclear if such changes are related to the increases in the amount of these reservoirs, or changes in the types of F deposits formed. New techniques have been developed for identifying and quantifying these deposits which should prove useful in developing agents that enhance formation of oral F reservoirs with optimum F release characteristics. Such research offers the prospect of decreasing the F content of topical agents while simultaneously increasing their cariostatic effect. Copyright © 2011 S. Karger AG, Basel.

  12. Fluoride toothpaste containing 1.5% arginine and insoluble calcium as a new standard of care in caries prevention.

    Science.gov (United States)

    ten Cate, J M; Cummins, D

    2013-01-01

    In spite of obvious achievements in prevention, caries remains a prevalent disease. Fluorides are effective by inhibiting enamel and dentin demineralization and enhancing remineralization, but have little or no influence on bacterial processes in dental plaque. Dental caries is a continuum of stages from reversible, early lesions to irreversible, pre-cavitated lesions and, ultimately, to cavities. Prevention should focus on strengthening protective and reducing pathological factors, and careful monitoring of the disease state. While fluoride and the mineral aspects of caries have been in focus for decades, new insights into the etiology of caries have generated novel concepts and approaches to its prevention and treatment. The observation that some plaque bacteria can produce alkali metabolites and, thus, raise pH or neutralize acid formed in plaque has long been known. Such pH rise factors are related to caries susceptibility. Nourishing the plaque with substrates that encourage alkali-producing reactions is a protective factor in the caries continuum. This article reviews the results of clinical studies with a novel toothpaste containing 1.5% arginine, an insoluble calcium compound, and fluoride which have demonstrated superior remineralization of white spot enamel lesions and rehardening of root surface lesions, favorable effects on the de-/remineralization balance, as well as superior cavity prevention efficacy compared to toothpaste with fluoride alone. Studies have also confirmed formation of ammonia and elevated pH levels in subjects using the arginine-containing toothpaste. This novel toothpaste effectively combines the established effects of fluoride on de- and remineralization with reduction of caries-inducing pathological factors resulting from plaque metabolism.

  13. Effect of gamma irradiation on fluoride release and antibacterial activity of resin dental materials

    International Nuclear Information System (INIS)

    Carvalho, Fabiola Galbiatti de; Fucio, Suzana Beatriz Portugal de; Correr-Sobrinho, Lourenco; Pascon, Fernanda Miori; Kantovitz, Kamila Rosamilia; Puppin-Rontani, Regina Maria

    2009-01-01

    This study evaluated the effect of gamma irradiation on fluoride release and antibacterial activity of FluroShield (FS) and Clearfil Protect Bond (CPB). Four groups were formed: G1-FS + gamma; G2-FS without gamma; G3-CPB + gamma; G4-CPB without gamma. For fluoride release analysis, 12 disks of each material were prepared and covered with nail polish, except for one side (50.4 mm 2 area). G1 and G3 were sterilized with a 14.5 KGy dose at 27 deg C for 24 h, while G2 and G4 (controls) were not sterilized and were maintained under the same time and temperature conditions. Fluoride release measurements were made in duplicate (n=6) by an ion specific electrode. The antibacterial activity of the CPB and FS against Streptococcus mutans after gamma sterilization was evaluated by the agar-disc diffusion method. The diameter of the zones of microbial growth inhibition was recorded after 48 h. Data were analyzed statistically by ANOVA and Tukey's test (alpha=5%). Gamma sterilization decreased the fluoride release of FS by approximately 50%, while CPB was not affected. There was no statistically significant difference (p>0.05) in the antibacterial effect of CPB between gamma and non-gamma sterilization groups. FS presented no antibacterial activity. Gamma irradiation decreased the fluoride release of FS, but did not affect the antibacterial activity of the studied materials. (author)

  14. Effect of gamma irradiation on fluoride release and antibacterial activity of resin dental materials

    Energy Technology Data Exchange (ETDEWEB)

    Carvalho, Fabiola Galbiatti de; Fucio, Suzana Beatriz Portugal de; Correr-Sobrinho, Lourenco [Universidade Estadual de Campinas (UNICAMP), Piracicaba, SP (Brazil). Piracicaba Dental School. Dept. of Dental Materials; Pascon, Fernanda Miori; Kantovitz, Kamila Rosamilia; Puppin-Rontani, Regina Maria [Universidade Estadual de Campinas (UNICAMP), Piracicaba, SP (Brazil). Piracicaba Dental School. Dept. of Pedriatric Dentistry], e-mail: rmpuppin@fop.unicamp.br

    2009-07-01

    This study evaluated the effect of gamma irradiation on fluoride release and antibacterial activity of FluroShield (FS) and Clearfil Protect Bond (CPB). Four groups were formed: G1-FS + gamma; G2-FS without gamma; G3-CPB + gamma; G4-CPB without gamma. For fluoride release analysis, 12 disks of each material were prepared and covered with nail polish, except for one side (50.4 mm{sup 2} area). G1 and G3 were sterilized with a 14.5 KGy dose at 27 deg C for 24 h, while G2 and G4 (controls) were not sterilized and were maintained under the same time and temperature conditions. Fluoride release measurements were made in duplicate (n=6) by an ion specific electrode. The antibacterial activity of the CPB and FS against Streptococcus mutans after gamma sterilization was evaluated by the agar-disc diffusion method. The diameter of the zones of microbial growth inhibition was recorded after 48 h. Data were analyzed statistically by ANOVA and Tukey's test (alpha=5%). Gamma sterilization decreased the fluoride release of FS by approximately 50%, while CPB was not affected. There was no statistically significant difference (p>0.05) in the antibacterial effect of CPB between gamma and non-gamma sterilization groups. FS presented no antibacterial activity. Gamma irradiation decreased the fluoride release of FS, but did not affect the antibacterial activity of the studied materials. (author)

  15. Effects of fluoride and epigallocatechin gallate on soft-drink-induced dental erosion of enamel and root dentin.

    Science.gov (United States)

    Wang, Yin-Lin; Chang, Hao-Hueng; Chiang, Yu-Chih; Lu, Yu-Chen; Lin, Chun-Pin

    2018-04-01

    Fluoride and epigallocatechin gallate (EGCG) have been proven to prevent dental caries. The purpose of this study was to evaluate the effects of fluoride and EGCG on soft-drink-induced dental erosion in vitro. Forty enamel and dentin specimens were prepared from extracted human teeth. The specimens were divided into 4 groups and treated separately with distilled water (as control), 0.5 M sodium fluoride (NF), 400 μM EGCG (EG), and a solution containing 0.5 M NaF and 400 μM EGCG (FG). Cyclic erosive treatment was performed according to the experimental procedures. The specimens were analyzed using laser scanning confocal microscopy, scanning electron microscopy, and a microhardness tester. The data were analyzed using ANOVA and Bonferroni's post hoc test. The significance level was set at 5%. The amount of substance loss was lower in the NF and EG groups than in the control group (p erosion-caused substance loss was more pronounced in the dentin than in the enamel specimens. Surface microhardness loss was lower in the NF and EG groups than in the control group (p erosion compared with the control group. Fluoride and EGCG may interfere with each other. The mechanisms of the anti-erosive effect need to be explored in the future. Copyright © 2018. Published by Elsevier B.V.

  16. Effect of Fluoride Mouthrinse and Toothpaste on Number of Streptococcal Colony Forming Units of Dental Plaque

    OpenAIRE

    SE Jabbarifar; SA Tabibian; F Poursina

    2005-01-01

    Background: Frequent topical fluoride therapy through toothpaste, mouthrinse, professional gels and solutions causes decrease in incidence, pause and repair of dental caries in the enamel. These mechanisms are done through penetration of fluoride ions (F-) and their replacement with hydroxyl ions (OH-) of hydroxyappatite of enamel, interfere with microbial metabolism of dental plaque and bacteriostatic effect on some cariogenic bacterial strains such as streptococci. The aim of this study was...

  17. Fluorine analysis of human enamel around fluoride-containing materials under different pH-cycling by {mu}-PIGE/PIXE system

    Energy Technology Data Exchange (ETDEWEB)

    Komatsu, H., E-mail: kom@den.hokudai.ac.jp [Graduate School of Dental Medicine, Hokkaido University, Kita-13, Nishi-7, Kita-ku, Sapporo 060-8586 (Japan); Yamamoto, H. [Graduate School of Dentistry, Osaka University, 1-8 Yamada-Oka, Suita 565-0871 (Japan); Matsuda, Y.; Kijimura, T.; Kinugawa, M.; Okuyama, K. [Graduate School of Dental Medicine, Hokkaido University, Kita-13, Nishi-7, Kita-ku, Sapporo 060-8586 (Japan); Nomachi, M. [Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka 560-0043 (Japan); Yasuda, K. [Wakasa Wan Energy Research Center, 64-52-1 Hase, Tsuruga 914-0192 (Japan); Satoh, T. [Advanced Radiation Technology, TARRI, JAEA, 1233 Watanuki-Machi, Takasaki 370-1292 (Japan); Oikawa, S. [National Institute of Radiological Science, 4-9-1, Anagawa, Inage-ku, Chiba 263-8555 (Japan)

    2011-10-15

    The caries preventive effect of fluoride-containing materials (FCMs) might depend on the caries risk of the individuals. Two pairs of demineralizing and remineralizing solutions of pH-cycling were prepared for simulating low and high caries risk. The purpose of this study was to determine fluorine (F) uptake into human enamel around FCMs under different pH-cycling using the in-air {mu}-PIGE/PIXE system. Fluoride-containing glass ionomer cement (Fuji IX{sub GP} FAST CAPSULE (FN)), and composite resin (BEAUTIFIL II with FLUORO BOND SHAKE ONE (BS)) were used in this study. The pH-cycling (pH 6.8-4.5) was carried out for 5 weeks. After pH-cycling, the caries progression was analyzed using transverse micro-radiography (TMR). The fluorine and calcium distributions in the carious lesion in each specimen were evaluated using the PIGE/PIXE system. From TMR analysis, there was a difference in caries risk between the two kinds of pH-cycling. Although the caries preventive effect of BS and FN was confirmed at low risk, the effect at high risk was confirmed for FN only. From the analysis of the fluorine uptake in the outer 200 {mu}m of the lesion we concluded that there was no significant difference between the pH-cycling solutions. However, we found different fluorine concentrations in the enamel for the two FCMs. The decreased caries progression under high risk for FN indicated that an adequate amount of fluorine supplied from the material is required at higher caries risk. It was confirmed that the caries preventive effect of FCM depends on the caries risk. The fluorine analysis of teeth under various pH-cycling conditions gives information to evaluate the caries preventive effect of fluoride-containing materials according to the caries risk.

  18. Fluorine analysis of human enamel around fluoride-containing materials under different pH-cycling by μ-PIGE/PIXE system

    International Nuclear Information System (INIS)

    Komatsu, H.; Yamamoto, H.; Matsuda, Y.; Kijimura, T.; Kinugawa, M.; Okuyama, K.; Nomachi, M.; Yasuda, K.; Satoh, T.; Oikawa, S.

    2011-01-01

    The caries preventive effect of fluoride-containing materials (FCMs) might depend on the caries risk of the individuals. Two pairs of demineralizing and remineralizing solutions of pH-cycling were prepared for simulating low and high caries risk. The purpose of this study was to determine fluorine (F) uptake into human enamel around FCMs under different pH-cycling using the in-air μ-PIGE/PIXE system. Fluoride-containing glass ionomer cement (Fuji IX GP FAST CAPSULE (FN)), and composite resin (BEAUTIFIL II with FLUORO BOND SHAKE ONE (BS)) were used in this study. The pH-cycling (pH 6.8-4.5) was carried out for 5 weeks. After pH-cycling, the caries progression was analyzed using transverse micro-radiography (TMR). The fluorine and calcium distributions in the carious lesion in each specimen were evaluated using the PIGE/PIXE system. From TMR analysis, there was a difference in caries risk between the two kinds of pH-cycling. Although the caries preventive effect of BS and FN was confirmed at low risk, the effect at high risk was confirmed for FN only. From the analysis of the fluorine uptake in the outer 200 μm of the lesion we concluded that there was no significant difference between the pH-cycling solutions. However, we found different fluorine concentrations in the enamel for the two FCMs. The decreased caries progression under high risk for FN indicated that an adequate amount of fluorine supplied from the material is required at higher caries risk. It was confirmed that the caries preventive effect of FCM depends on the caries risk. The fluorine analysis of teeth under various pH-cycling conditions gives information to evaluate the caries preventive effect of fluoride-containing materials according to the caries risk.

  19. The Effects of Remineralization via Fluoride Versus Low-Level Laser IR810 and Fluoride Agents on the Mineralization and Microhardness of Bovine Dental Enamel

    Directory of Open Access Journals (Sweden)

    Edith Lara-Carrillo

    2018-01-01

    Full Text Available The objective of this study was to assess the mineralization and microhardness of bovine dental enamel surfaces treated with fluoride, tri-calcium phosphate, and infrared (IR 810 laser irradiation. The study used 210 bovine incisors, which were divided into six groups (n = 35 in each: Group A: Untreated (control, Group B: Fluoride (Durapath-Colgate, Group C: Fluoride+Tri-calcium phosphate (Clin-Pro White-3 M, Group D: Laser IR 810 (Quantum, Group E: Fluoride+laser, and Group F: Fluoride+tri-calcium phosphate+laser. Mineralization was measured via UV-Vis spectroscopy for phosphorus and via atomic absorption spectroscopy for calcium upon demineralization and remineralization with proven agents. Microhardness (SMH was measured after enamel remineralization. Mineral loss data showed differences between the groups before and after the mineralizing agents were placed (p < 0.05. Fluoride presented the highest remineralization tendency for both calcium and phosphate, with a Vickers microhardness of 329.8 HV0.1/11 (p < 0.05. It was observed that, if remineralization solution contained fewer minerals, the microhardness surface values were higher (r = −0.268 and −0.208; p < 0.05. This study shows that fluoride has a remineralizing effect compared with calcium triphosphate and laser IR810. This in vitro study imitated the application of different remineralizing agents and showed which one was the most efficient for treating non-cavitated injuries. This can prevent the progression of lesions in patients with white spot lesions.

  20. Combinatorial effects of arginine and fluoride on oral bacteria.

    Science.gov (United States)

    Zheng, X; Cheng, X; Wang, L; Qiu, W; Wang, S; Zhou, Y; Li, M; Li, Y; Cheng, L; Li, J; Zhou, X; Xu, X

    2015-02-01

    Dental caries is closely associated with the microbial disequilibrium between acidogenic/aciduric pathogens and alkali-generating commensal residents within the dental plaque. Fluoride is a widely used anticaries agent, which promotes tooth hard-tissue remineralization and suppresses bacterial activities. Recent clinical trials have shown that oral hygiene products containing both fluoride and arginine possess a greater anticaries effect compared with those containing fluoride alone, indicating synergy between fluoride and arginine in caries management. Here, we hypothesize that arginine may augment the ecological benefit of fluoride by enriching alkali-generating bacteria in the plaque biofilm and thus synergizes with fluoride in controlling dental caries. Specifically, we assessed the combinatory effects of NaF/arginine on planktonic and biofilm cultures of Streptococcus mutans, Streptococcus sanguinis, and Porphyromonas gingivalis with checkerboard microdilution assays. The optimal NaF/arginine combinations were selected, and their combinatory effects on microbial composition were further examined in single-, dual-, and 3-species biofilm using bacterial species-specific fluorescence in situ hybridization and quantitative polymerase chain reaction. We found that arginine synergized with fluoride in suppressing acidogenic S. mutans in both planktonic and biofilm cultures. In addition, the NaF/arginine combination synergistically reduced S. mutans but enriched S. sanguinis within the multispecies biofilms. More importantly, the optimal combination of NaF/arginine maintained a "streptococcal pressure" against the potential growth of oral anaerobe P. gingivalis within the alkalized biofilm. Taken together, we conclude that the combinatory application of fluoride and arginine has a potential synergistic effect in maintaining a healthy oral microbial equilibrium and thus represents a promising ecological approach to caries management. © International & American

  1. Exploring the short-term impact of community water fluoridation cessation on children's dental caries: a natural experiment in Alberta, Canada.

    Science.gov (United States)

    McLaren, L; Patterson, S; Thawer, S; Faris, P; McNeil, D; Potestio, M L; Shwart, L

    2017-05-01

    Dental caries (tooth decay) is common and can be serious. Dental caries is preventable, and community water fluoridation is one means of prevention. There is limited current research on the implications of fluoridation cessation for children's dental caries. Our objective was to explore the short-term impact of community water fluoridation cessation on children's dental caries, by examining change in caries experience in population-based samples of schoolchildren in two Canadian cities, one that discontinued community water fluoridation and one that retained it. We used a pre-post cross-sectional design. We examined dental caries indices (deft [number of decayed, extracted, or filled primary teeth] and DMFT [number of decayed, missing, or filled permanent teeth]) among grade 2 schoolchildren in 2004/05 and 2013/14 in two similar cities in the province of Alberta, Canada: Calgary (cessation of community water fluoridation in 2011) and Edmonton (still fluoridated). We compared change over time in the two cities. For Calgary only, we had a third data point from 2009/10, and we considered trends across the three points. We observed a worsening in primary tooth caries (deft) in Calgary and Edmonton, but changes in Edmonton were less consistent and smaller. This effect was robust to adjustment for covariates available in 2013/14 and was consistent with estimates of total fluoride intake from biomarkers from a subsample. This finding occurred despite indication that treatment activities appeared better in Calgary. The worsening was not observed for permanent teeth. For prevalence estimates only (% with >0 deft or DMFT), the three data points in Calgary suggest a trend that, though small, appears consistent with an adverse effect of fluoridation cessation. Our results suggest an increase in dental caries in primary teeth during a time period when community fluoridation was ceased. That we did not observe a worsening for permanent teeth in the comparative analysis could

  2. IN VITRO EVALUATION OF FLUORIDE RELEASE OF JELTRATE® DENTAL ALGINATE

    Directory of Open Access Journals (Sweden)

    Matheus Melo Pithon

    2009-04-01

    Full Text Available Objective: To evaluate of fluoride release from Jeltrate alginate®. Materials and Methods: Four Trademarks of alginate were divided in four groups: conventional Jeltrate®, Plus Jeltrate®, Chromatic Jeltrate® and Chromatic Ortho Jeltrate®. The alginates were handled following the guidelines of the manufacturers. After this was followed by the construction of evidence bodies using silicone molds of the dimensions of 4 mm in diameter and 4mm in height. After take prey, the evidence bodies were removed from the molds and placed in container with 10 ml of ultra purified water, for 2 min. The fluoride release was measured by selective ion electrode connected to an analyzer of ions. Results: The Plus Jeltrate® showed a higher releasing fluoride 247.85 µg/cm2 followed by Chromatic Ortho Jeltrate® (217.83 µg/cm2, Chromatic Jeltrate ® (138.21 µg/cm2 and Jeltrate® (79.61 µg/cm2. Conclusion: Plus Jeltrate® had the best performance in releasing fluoride, followed by Chromatic Ortho Jeltrate®, Chromatic Jeltrate® and conventional Jeltrate®..

  3. Readying Community Water Fluoridation Advocates through Training, Surveillance, and Empowerment.

    Science.gov (United States)

    Veschusio, C; Jones, M K; Mercer, J; Martin, A B

    2018-05-30

    This paper describes the Community Water Fluoridation Advocacy Training Project that was designed to develop networks of community water fluoridation advocates in rural communities. The South Carolina (SC) Department of Health and Environmental Control Division of Oral Health staff and the SC Dental Association were responsible for developing and facilitating the training sessions for key policy influencers, which included medical and dental providers, early childhood educators, and water system operators and managers. Findings from the post-training survey indicate that participants increased their knowledge and skills to discuss the impact of water fluoridation on the dental health of community residents. Participants identified a need for online access to water fluoridation education and advocacy materials. Dental public health competencies illustrated: communication and collaboration with groups and individuals, and advocate, implement and evaluate public health policy, legislation and regulations. Copyright© 2018 Dennis Barber Ltd.

  4. 4-phenylbutyrate Mitigates Fluoride-Induced Cytotoxicity in ALC Cells

    Directory of Open Access Journals (Sweden)

    Maiko Suzuki

    2017-05-01

    Full Text Available Chronic fluoride over-exposure during pre-eruptive enamel development can cause dental fluorosis. Severe dental fluorosis is characterized by porous, soft enamel that is vulnerable to erosion and decay. The prevalence of dental fluorosis among the population in the USA, India and China is increasing. Other than avoiding excessive intake, treatments to prevent dental fluorosis remain unknown. We previously reported that high-dose fluoride induces endoplasmic reticulum (ER stress and oxidative stress in ameloblasts. Cell stress induces gene repression, mitochondrial damage and apoptosis. An aromatic fatty acid, 4-phenylbutyrate (4PBA is a chemical chaperone that interacts with misfolded proteins to prevent ER stress. We hypothesized that 4PBA ameliorates fluoride-induced ER stress in ameloblasts. To determine whether 4PBA protects ameloblasts from fluoride toxicity, we analyzed gene expression of Tgf-β1, Bcl2/Bax ratio and cytochrome-c release in vitro. In vivo, we measured fluorosis levels, enamel hardness and fluoride concentration. Fluoride treated Ameloblast-lineage cells (ALC had decreased Tgf-β1 expression and this was reversed by 4PBA treatment. The anti-apoptotic Blc2/Bax ratio was significantly increased in ALC cells treated with fluoride/4PBA compared to fluoride treatment alone. Fluoride treatment induced cytochrome-c release from mitochondria into the cytosol and this was inhibited by 4PBA treatment. These results suggest that 4PBA mitigates fluoride-induced gene suppression, apoptosis and mitochondrial damage in vitro. In vivo, C57BL/6J mice were provided fluoridated water for six weeks with either fluoride free control-chow or 4PBA-containing chow (7 g/kg 4PBA. With few exceptions, enamel microhardness, fluorosis levels, and fluoride concentrations of bone and urine did not differ significantly between fluoride treated animals fed with control-chow or 4PBA-chow. Although 4PBA mitigated high-dose fluoride toxicity in vitro, a diet

  5. 4-phenylbutyrate Mitigates Fluoride-Induced Cytotoxicity in ALC Cells.

    Science.gov (United States)

    Suzuki, Maiko; Everett, Eric T; Whitford, Gary M; Bartlett, John D

    2017-01-01

    Chronic fluoride over-exposure during pre-eruptive enamel development can cause dental fluorosis. Severe dental fluorosis is characterized by porous, soft enamel that is vulnerable to erosion and decay. The prevalence of dental fluorosis among the population in the USA, India and China is increasing. Other than avoiding excessive intake, treatments to prevent dental fluorosis remain unknown. We previously reported that high-dose fluoride induces endoplasmic reticulum (ER) stress and oxidative stress in ameloblasts. Cell stress induces gene repression, mitochondrial damage and apoptosis. An aromatic fatty acid, 4-phenylbutyrate (4PBA) is a chemical chaperone that interacts with misfolded proteins to prevent ER stress. We hypothesized that 4PBA ameliorates fluoride-induced ER stress in ameloblasts. To determine whether 4PBA protects ameloblasts from fluoride toxicity, we analyzed gene expression of Tgf -β 1, Bcl2 / Bax ratio and cytochrome-c release in vitro . In vivo , we measured fluorosis levels, enamel hardness and fluoride concentration. Fluoride treated Ameloblast-lineage cells (ALC) had decreased Tgf -β 1 expression and this was reversed by 4PBA treatment. The anti-apoptotic Blc2 / Bax ratio was significantly increased in ALC cells treated with fluoride/4PBA compared to fluoride treatment alone. Fluoride treatment induced cytochrome-c release from mitochondria into the cytosol and this was inhibited by 4PBA treatment. These results suggest that 4PBA mitigates fluoride-induced gene suppression, apoptosis and mitochondrial damage in vitro . In vivo , C57BL/6J mice were provided fluoridated water for six weeks with either fluoride free control-chow or 4PBA-containing chow (7 g/kg 4PBA). With few exceptions, enamel microhardness, fluorosis levels, and fluoride concentrations of bone and urine did not differ significantly between fluoride treated animals fed with control-chow or 4PBA-chow. Although 4PBA mitigated high-dose fluoride toxicity in vitro , a diet rich

  6. Effect of fluoride varnishes on color stability of esthetic restorative materials.

    Science.gov (United States)

    Autio-Gold, Jaana T; Barrett, Allyson A

    2004-01-01

    Fluoride varnish applications were applied to two hybrid resin composite materials, Z-100 (3M Dental Products, St Paul, MN, USA) and Esthet-X (Dentsply Caulk, Milford, DE, USA), shades A1 and A2 and a glass ionomer, GC Fuji IX GP Fast (GC Corporation, Tokyo, Japan), shade A2, to evaluate color stability. Specimens (12.6-mm dia x 2.3 mm) were prepared using a polyethylene frame, light-cured and polished through a 1-microm alumina finish. After the initial baseline color measurements, the discs were suspended in Fusayama artificial saliva (FAS) solution at 37 degrees C for 48 hours. Post immersion, the specimens were divided into five groups (n=15 each). The following fluoride varnishes were applied to four groups of test specimens: Duraphat (Colgate Oral Pharmaceutical, Inc, Canton MA, USA), Cavity Shield (OMNII Oral Pharmaceuticals, West Palm Beach, FL, USA), Duraflor (Pharmascience Inc, Montreal, Canada) and Fluor Protector (Vivadent, Ivoclar North America, Amherst, NY, USA). The varnish was allowed to dry for five minutes before immersion. The control group was not coated with varnish, although the specimens were immersed in FAS. All specimens were incubated in newly prepared FAS at 37 degrees C for 24 hours, cleaned with an electric toothbrush and the process repeated using newly prepared FAS. CIE L*a*b* color measurements were recorded five times: at baseline, after 48 hours FAS immersion, after cleaning the first and second fluoride varnish applications and after the final brushing using a commercial toothpaste (Crest). A Minolta CR-300 tristimulus colorimeter with an 8-mm aperture (Ramsey, NJ, USA) was used to record color measurements with the daylight (D65) setting. Calculations were performed for using CIE parameters deltaE*, deltaL*, delta a*, delta b*. Analysis of variance (ANOVA) and post-hoc test (Fisher's PLSD) were used for statistical analysis. After immersion in saliva, the tested glass ionomer (Fuji IX) produced the most significant color changes

  7. The relationships between low levels of urine fluoride on children's intelligence, dental fluorosis in endemic fluorosis areas in Hulunbuir, Inner Mongolia, China.

    Science.gov (United States)

    Ding, Yunpeng; YanhuiGao; Sun, Huixin; Han, Hepeng; Wang, Wei; Ji, Xiaohong; Liu, Xuehui; Sun, Dianjun

    2011-02-28

    There has been public concern about children's intellectual performance at high levels of fluoride exposure, but few studies provide data directly to the question of whether low fluoride exposure levels less than 3.0 mg/L in drinking water adversely associated with children's intelligence. In this survey, we investigated the effects of low fluoride exposure on children's intelligence and dental fluorosis. 331 children aged from 7 to 14 were randomly recruited from four sites in Hulunbuir City, China. Intelligence was assessed using Combined Raven Test-The Rural in China while dental fluorosis was diagnosed with Dean's index. Mean value of fluoride in drinking water was 1.31±1.05 mg/L (range 0.24-2.84). Urine fluoride was inversely associated with IQ in the multiple linear regression model when children's age as a covariate variable was taken into account (Pintelligence and dental health and confirmed the dose-response relationships between urine fluoride and IQ scores as well as dental fluorosis. Copyright © 2010 Elsevier B.V. All rights reserved.

  8. Nutritional status and dental fluorosis among schoolchildren in communities with different drinking water fluoride concentrations in a central region in Mexico.

    Science.gov (United States)

    Irigoyen-Camacho, M E; García Pérez, A; Mejía González, A; Huizar Alvarez, R

    2016-01-15

    Poor water quality and under nutrition are important factors affecting the health of many communities in developing countries. The aims of this study were: i) to describe the fluoride water concentration and the hydrogeological conditions in a region of a state located in the central in Mexico ii) to measure the association between undernutrition and dental fluorosis in children living in communities with different drinking water fluoride concentrations in a state located in the central region of Mexico. Field work was performed in the region to identify the prevailing groundwater flow characteristics and water wells were sampled to analyze water fluoride concentration. Children were selected from three communities that had different drinking water fluoride concentrations (i.e., 0.56, 0.70 and 1.60 mg/l). Fluoridated salt was available in these communities. The Thylstrup-Fejerskov Index (TFI) was used to assess dental fluorosis. Categories four or higher of this index involve changes in the entire tooth surface (ITF ≥ 4). The weight and height of the children were measured. The assessment of undernutrition was based on the World Health Organization criteria: children were classified as being at risk of low-height (Height-for-Age Z score water captured by the wells is the result of a reaction with volcanic materials. The water fluoride concentration in the region ranged from 0.2 to 1.6 mg/l. A total of 734 schoolchildren participated in the study. The percentage of children in fluorosis categories (ITF ≥ 4) was 15.9%, 21.1% of the children were at risk of low height-for-age, and 8.0% had low height-for-age. The percentage of children with fluorosis (ITF ≥ 4) was 6.3%, 9.1% and 31.9% (p ˂ 0.001) and low high-for-age was 2.9%, 2.5% and 8.4% (p ˂ 0.001), for the communities with F concentrations of 0.56 mg/l, 0.70 mg/l and 1.6 mg/l, respectively. The logistic regression model showed an association between dental fluorosis (TFI ≥ 4) and low height-for-age (OR

  9. Effect of an essential oil-containing dentifrice on dental plaque microbial composition.

    Science.gov (United States)

    Charles, C H; Vincent, J W; Borycheski, L; Amatnieks, Y; Sarina, M; Qaqish, J; Proskin, H M

    2000-09-01

    To determine the effect of 6 months use of an essential oil-containing (EO) antiplaque/antigingivitis fluoride dentifrice on the balance of the oral microbial flora and on the emergence of resistant microbial forms by analysis of dental plaque and saliva. The dentifrice essential oils consisted of a fixed combination of thymol, menthol, methyl salicylate, and eucalyptol. An identical fluoride-containing dentifrice without the essential oils served as the control. A subgroup of 66 subjects from a clinical trial population of 321 was randomly selected for characterization of their dental plaque microflora. Saliva was also cultured to monitor for the emergence of opportunistic pathogens. Supragingival plaque and saliva were harvested at baseline, after which subjects received a dental prophylaxis. Subjects were sampled again after 3 and 6 months of product use prior to clinical examination. Plaque was characterized for microbial content by phase contrast microscopy for recognizable cellular morphotypes and by cultivation on nonselective and selective culture media. Determination of the minimum inhibitory concentrations of the test agent against selected Actinomyces and Veillonella isolated bacterial species was conducted at all time points to monitor for the potential development of bacterial resistance. There were no statistically significant differences between the microbial flora obtained from subjects using the essential oil-containing dentifrice and the vehicle control for all parameters and time periods except for the percentage of spirochetes at 6 months and for percentage of "other" microorganisms at 3 months. The EO group exhibited a lower adjusted mean for both parameters. Additionally, there was no evidence of the development of bacterial resistance to the antimicrobial activity of the essential oils or the emergence of opportunistic pathogens.

  10. Purification process of uranium hexafluoride containing traces of plutonium fluoride and/or neptunium fluoride

    International Nuclear Information System (INIS)

    Aubert, J.; Bethuel, L.; Carles, M.

    1983-01-01

    In this process impure uranium hexafluoride is contacted with a metallic fluoride chosen in the group containing lead fluoride PbF 2 , uranium fluorides UFsub(4+x) (0 3 at a temperature such as plutonium and/or neptunium are reduced and pure uranium hexafluoride is recovered. Application is made to uranium hexafluoride purification in spent fuel reprocessing [fr

  11. Changes in the Concentration of Ions in Saliva and Dental Plaque after Application of CPP-ACP with and without Fluoride among 6-9 Year Old Children

    Directory of Open Access Journals (Sweden)

    Poureslami H

    2017-03-01

    Full Text Available Statement of Problem: The casein phospho peptide-amorphous calcium phosphate with or without fluoride (CPP-ACPF and CPP-ACP respectively are of considerably new materials which are highly recommended for prevention of dental caries. However, there is a shortage in literature on how they affect the ion concentration of saliva or dental plaque. Objectives: The aim of this study was to evaluate the concentration of calcium, phosphate and fluoride in the plaque and saliva of children with Early Childhood Caries (ECC after applying the CPP-ACP paste in comparison with the use of CPP- ACPF paste. Materials and Methods: One ml of un-stimulated saliva of 25 preschool children was collected and then 1 mg of the plaque sample was collected from the buccal surfaces of the two first primary molars on the upper jaw. CPP-ACP as well as CPP- ACPF pastes were applied on the tooth surfaces in two separate steps. In steps, plaque and saliva sampling was performed after 60 minutes. The amount of calcium ions was measured by Atomic Absorption Device and the amount of phosphate and fluoride ions was measured by Ion Chromatography instrument. Data were analyzed using Repeated Measurements ANOVA at a p < 0.05 level of significance. Results: Application of both CPP-ACPF and CPP-ACP significantly increased the concentration of calcium, phosphate, and fluoride in both saliva and dental plaque. Moreover, significantly higher salivary fluoride concentration was seen after application of CPP-ACPF compared to CPP-ACP. No other significant difference was observed between these two materials. Conclusions: CPP-ACPF can be more useful than CPP-ACP in protecting the primary teeth against caries process, especially when there is poor hygiene.

  12. Dental Fluorosis and Catalase Immunoreactivity of the Brain Tissues in Rats Exposed to High Fluoride Pre- and Postnatally.

    Science.gov (United States)

    Güner, Şirin; Uyar-Bozkurt, Süheyla; Haznedaroğlu, Eda; Menteş, Ali

    2016-11-01

    This study evaluated dental fluorosis of the incisors and immunoreactivity in the brain tissues of rats given chronic fluoride doses pre- and postnatally. Female rats were given drinking water with 0, 30 or 100 ppm fluoride ad libitum throughout gestation and the nursing period. In addition, 63 male offspring were treated with the same water regimens as the mothers after weaning and were followed for 1, 3 or 5 months. The upper and lower incisors were collected, and all teeth were examined under a stereomicroscope and scored by two blinded examiners using a modified rodent enamel fluorosis index. Cortical, hippocampal and cerebellar brain samples were evaluated morphologically and immunohistochemically. All fluoride-treated pups were born with low body weight (p = 0.001). All animals from the fluoride groups had enamel fluorosis with defects of various degrees. The increase in the dental fluorosis scores in the fluoride treatment groups was significant (p fluoride groups was significantly higher than that in the controls after 1, 3 and 5 months (p toxicity of fluoride.

  13. Fluoride Concentration of Drinking-Water of Qom, Iran

    Directory of Open Access Journals (Sweden)

    Ahmad Reza Yari

    2016-03-01

    Full Text Available Background and Purpose: Fluoride is a natural element essential for human nutrition due to its benefits for dental enamel. It is well-documented that standard amounts of fluoride in drinkingwater can decrease the rate of dental caries. This study was conducted with the aim of measuring fluoride concentration of drinking-water supplies and urban distribution system in Qom, Iran. Materials and Methods: Results were subsequently compared against national and international standards. All sources of drinking-water of rural and urban areas were examined. To measure fluoride, the standard SPADNS method and a DR/4000s spectrophotometer were used. Results: Results showed that the mean of fluoride concentration in rural areas, mainly supplied with groundwater sources, was 0.41 mg/L, that of the urban distribution system 0.82 mg/L, that of Ali-Abad station 0.11 mg/L, and that of the private water desalination system 0.24 mg/L. Due to the hot climate of Qom, fluoride concentration means of all sources were lower than the permissible standards set by Iranian Standards and the WHO guidelines (except those of some of the groundwater sources and urban distribution systems. Conclusion: It seems that in most of the drinking-water sources the average fluoride concentration is not enough to prevent dental caries or strengthen dental enamel. It is concluded that Qom’s drinkingwater would require at least 0.4 mg/L to reach the minimum desirable standard.

  14. Association between urine fluoride and dental fluorosis as a toxicity factor in a rural community in the state of San Luis Potosi.

    Science.gov (United States)

    Jarquín-Yañez, Lizet; de Jesús Mejía-Saavedra, José; Molina-Frechero, Nelly; Gaona, Enrique; Rocha-Amador, Diana Olivia; López-Guzmán, Olga Dania; Bologna-Molina, Ronell

    2015-01-01

    The aim of this study is to investigate urine fluoride concentration as a toxicity factor in a rural community in the state of San Luis Potosi, Mexico. A sample of 111 children exposed to high concentrations of fluoride in drinking water (4.13 mg/L) was evaluated. Fluoride exposure was determined by measuring urine fluoride concentration using the potentiometric method with an ion selective electrode. The diagnosis of dental fluorosis was performed by clinical examination, and the severity of damage was determined using Dean's index and the Thylstrup-Fejerskov (TF) index. The range of exposure in the study population, evaluated through the fluoride content in urine, was 1.1 to 5.9 mg/L, with a mean of 3.14±1.09 mg/L. Dental fluorosis was present in all subjects, of which 95% had severe cases. Higher urine fluoride levels and greater degrees of severity occurred in older children. The results show that dental fluorosis was determined by the presence of fluoride exposure finding a high positive correlation between the severity of fluorosis and urine fluoride concentration and the years of exposure suggested a cumulative effect.

  15. Estimation of fluoride levels in various commercially available carbonated soft drinks in Chandigarh city, India

    Directory of Open Access Journals (Sweden)

    Mohit Bansal

    2015-01-01

    Full Text Available Introduction: Fluoride has a preventive action on dental caries. However, Excessive ingestion of fluoride from different sources can lead to the development of dental fluorosis. Aim: To estimate fluoride levels in various commercially available carbonated soft drinks available in Chandigarh city. Materials and Methods: Twelve different brands of commercially available soft drinks were purchased from three different places and divided into three groups. Fluoride levels were estimated using fluoride test strips Quantofix 37211 Fluka; Sigma-Aldrich. Results: Fluoride levels ranged from 0.12 to 0.42 mg/dl F with the maximum level in Thumbs up and least in Diet Pepsi. Conclusion: The levels of fluoride varied in various carbonated soft drinks analyzed. This could contribute significantly to the total fluoride intake from all sources and thus be an important risk factor for the development of dental fluorosis.

  16. Fluoride salts and container materials for thermal energy storage applications in the temperature range 973 - 1400 K

    Science.gov (United States)

    Misra, Ajay K.; Whittenberger, J. Daniel

    1987-01-01

    Multicomponent fluoride salt mixtures were characterized for use as latent heat of fusion heat storage materials in advanced solar dynamic space power systems with operating temperatures in the range of 973 to 1400 K. The melting points and eutectic composition for many systems with published phase diagrams were verified, and several new eutectic compositions were identified. Additionally, the heats of fusion of several binary and ternary eutectics and congruently melting intermediate compounds were measured by differential scanning calorimetry. The extent of corrosion of various metals by fluoride melts was estimated from thermodynamic considerations, and equilibrium conditions inside a containment vessel were calculated as functions of the initial moisture content of the salt and free volume above the molten salt. Preliminary experimental data on the corrosion of commercial, high-temperature alloys in LiF-19.5CaF2 and NaF-27CaF2-36MgF2 melts are presented and compared to the thermodynamic predictions.

  17. Changes in the Concentration of Ions in Saliva and Dental Plaque after Application of CPP-ACP with and without Fluoride among 6-9 Year Old Children.

    Science.gov (United States)

    Poureslami, H; Hoseinifar, Ra; Khazaeli, P; Hoseinifar, Re; Sharifi, H; Poureslami, P

    2017-03-01

    The casein phospho peptide-amorphous calcium phosphate with or without fluoride (CPP-ACPF and CPP-ACP respectively) are of considerably new materials which are highly recommended for prevention of dental caries. However, there is a shortage in literature on how they affect the ion concentration of saliva or dental plaque. The aim of this study was to evaluate the concentration of calcium, phosphate and fluoride in the plaque and saliva of children with Early Childhood Caries (ECC) after applying the CPP-ACP paste in comparison with the use of CPP-ACPF paste. One ml of un-stimulated saliva of 25 preschool children was collected and then 1 mg of the plaque sample was collected from the buccal surfaces of the two first primary molars on the upper jaw. CPP-ACP as well as CPP-ACPF pastes were applied on the tooth surfaces in two separate steps. In steps, plaque and saliva sampling was performed after 60 minutes. The amount of calcium ions was measured by Atomic Absorption Device and the amount of phosphate and fluoride ions was measured by Ion Chromatography instrument. Data were analyzed using Repeated Measurements ANOVA at a p Application of both CPP-ACPF and CPP-ACP significantly increased the concentration of calcium, phosphate, and fluoride in both saliva and dental plaque. Moreover, significantly higher salivary fluoride concentration was seen after application of CPP-ACPF compared to CPP-ACP. No other significant difference was observed between these two materials. CPP-ACPF can be more useful than CPP-ACP in protecting the primary teeth against caries process, especially when there is poor hygiene.

  18. Effect of dentifrice containing fluoride and/or baking soda on enamel demineralization/remineralization: an in situ study.

    Science.gov (United States)

    Cury, J A; Hashizume, L N; Del Bel Cury, A A; Tabchoury, C P

    2001-01-01

    The additive effect of baking soda on the anticariogenic effect of fluoride dentifrice is not well established. To evaluate it, a crossover in situ study was done in three phases of 28 days. Volunteers, using acrylic palatal appliances containing four human enamel blocks, two sound (to evaluate demineralization) and two with artificial caries lesions (to evaluate remineralization), took part in this study. During each phase, 10% sucrose solution was dripped (3 times a day) only onto the sound blocks. After 10 min, a slurry of placebo, fluoride (F) or fluoride and baking soda (F+NaHCO(3)) dentifrice was dripped onto all enamel blocks. The results showed a higher F concentration in dental plaque formed during treatment with F+NaHCO(3) than placebo (pbaking soda neither improves nor impairs the effect of F dentifrice on reduction of demineralization and enhancement of remineralization of enamel.

  19. Does the Presense of Water Fluoridation Alter the Use of Dental Preventive Services on United States Air Force Bases?

    National Research Council Canada - National Science Library

    Bober-Moken, Irene

    1999-01-01

    ... application of fluorides, oral hygiene counseling, diet planning and dental prophylaxis. Are these procedures employed at different rates relative to the presence or absence of fluoride in the community water supply...

  20. Dietary Fluoride Intake and Associated Skeletal and Dental Fluorosis in School Age Children in Rural Ethiopian Rift Valley

    Directory of Open Access Journals (Sweden)

    Aweke Kebede

    2016-07-01

    Full Text Available An observational study was conducted to determine dietary fluoride intake, diet, and prevalence of dental and skeletal fluorosis of school age children in three fluorosis endemic districts of the Ethiopian Rift Valley having similar concentrations of fluoride (F in drinking water (~5 mg F/L. The duplicate plate method was used to collect foods consumed by children over 24 h from 20 households in each community (n = 60 and the foods, along with water and beverages, were analyzed for fluoride (F content. Prevalence of dental and skeletal fluorosis was determined using presence of clinical symptoms in children (n = 220. Daily dietary fluoride intake was at or above tolerable upper intake level (UL of 10 mg F/day and the dietary sources (water, prepared food and beverages all contributed to the daily fluoride burden. Urinary fluoride in children from Fentale and Adamitulu was almost twice (>5 mg/L the concentration found in urine from children from Alaba, where rain water harvesting was most common. Severe and moderate dental fluorosis was found in Alaba and Adamitulu, the highest severity and prevalence being in the latter district where staple foods were lowest in calcium. Children in all three areas showed evidence of both skeletal and non-skeletal fluorosis. Our data support the hypothesis that intake of calcium rich foods in addition to using rain water for household consumption and preparation of food, may help in reducing risk of fluorosis in Ethiopia, but prospective studies are needed.

  1. Dental fluorosis and dental caries prevalence among 12 and 15 ...

    African Journals Online (AJOL)

    Background: Fluoride is a double edged sword. The assessment of dental caries and fluorosis in endemic fluoride areas will facilitate in assessing the relation between fluoride concentrations in water with dental caries, dental fluorosis simultaneously. Aim: The objective of the following study is to assess the dental caries ...

  2. Process development for treatment of fluoride containing wastes

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Mahesh; Kanvinde, V Y [Chemical Engineering Division, Bhabha Atomic Research Centre, Mumbai (India)

    1994-06-01

    Many chemical and metallurgical industries generate liquid wastes containing high values of fluorides in association of nitrates and other metals. Due to harmful effects of fluorides these type of wastes can not be disposed off in the environment without proper treatment. Bench-scale laboratory experiments were conducted to develop a process scheme to fix the fluorides as non-leachable solid waste and fluoride free treated liquid waste for their disposal. To optimize the important parameters, simulated synthetic and actual wastes were used. For this study, three waste streams were collected from Nuclear Fuel Complex, Hyderabad. (author). 6 tabs., 1 fig.

  3. Fluoride gels for preventing dental caries in children and adolescents.

    Science.gov (United States)

    Marinho, Valeria C C; Worthington, Helen V; Walsh, Tanya; Chong, Lee Yee

    2015-06-15

    Topically applied fluoride gels have been widely used as a caries-preventive intervention in dental surgeries and school-based programmes for over three decades. This updates the Cochrane review of fluoride gels for preventing dental caries in children and adolescents that was first published in 2002. The primary objective is to determine the effectiveness and safety of fluoride gels in preventing dental caries in the child and adolescent population.The secondary objectives are to examine whether the effect of fluoride gels is influenced by the following: initial level of caries severity; background exposure to fluoride in water (or salt), toothpastes, or reported fluoride sources other than the study option(s); mode of use (self applied under supervision or operator-applied), and whether there is a differential effect between the tray and toothbrush methods of application; frequency of use (times per year) or fluoride concentration (ppm F). We searched the Cochrane Oral Health Group Trials Register (to 5 November 2014), the Cochrane Central Register of Controlled Trials (CENTRAL) (Cochrane Library 2014, Issue 11), MEDLINE via OVID (1946 to 5 November 2014), EMBASE via OVID (1980 to 5 November 2014), CINAHL via EBSCO (1980 to 5 November 2014), LILACS and BBO via the BIREME Virtual Health Library (1980 to 5 November 2014), ProQuest Dissertations and Theses (1861 to 5 November 2014) and Web of Science Conference Proceedings (1945 to 5 November 2014). We undertook a search for ongoing trials on ClinicalTrials.gov and the WHO International Clinical Trials Registry Platform on 5 November 2014. We placed no restrictions on language or date of publication in the search of the electronic databases. We also searched reference lists of articles and contacted selected authors and manufacturers. Randomised or quasi-randomised controlled trials where blind outcome assessment was stated or indicated, comparing topically applied fluoride gel with placebo or no treatment in

  4. Parent Refusal of Topical Fluoride for Their Children: Clinical Strategies and Future Research Priorities to Improve Evidence-Based Pediatric Dental Practice.

    Science.gov (United States)

    Chi, Donald L

    2017-07-01

    A growing number of parents are refusing topical fluoride for their children during preventive dental and medical visits. This nascent clinical and public health problem warrants attention from dental professionals and the scientific community. Clinical and community-based strategies are available to improve fluoride-related communications with parents and the public. In terms of future research priorities, there is a need to develop screening tools to identify parents who are likely to refuse topical fluoride and diagnostic instruments to uncover the reasons for topical fluoride refusal. This knowledge will lead to evidence-based strategies that can be widely disseminated into clinical practice. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. In vitro evaluation of fluoride release of Jeltrate® dental alginate

    Directory of Open Access Journals (Sweden)

    Delmo Santiago Vaitsman

    2009-01-01

    Full Text Available Objective: To evaluate of fluoride release from Jeltrate alginate®. Materials and Methods: Four Trademarks of alginate were divided in four groups: conventional Jeltrate®, Plus Jeltrate®, Chromatic Jeltrate® and Chromatic Ortho Jeltrate®. The alginates were handled following the guidelines of the manufacturers. After this was followed by the construction of evidence bodies using silicone molds of the dimensions of 4 mm in diameter and 4mm in height. After take prey, the evidence bodies were removed from the molds and placed in container with 10 ml of ultra purified water, for 2 min. The fluoride release was measured by selective ion electrode connected to an analyzer of ions. Results: The Plus Jeltrate® showed a higher releasing fluoride 247.85 μg/cm2 followed by Chromatic Ortho Jeltrate® (217.83 μg/cm2, Chromatic Jeltrate ® (138.21 μg/cm2 and Jeltrate® (79.61 μg/cm2. Conclusion: Plus Jeltrate® had the best performance in releasing fluoride, followed by Chromatic Ortho Jeltrate®, Chromatic Jeltrate® and conventional Jeltrate®.

  6. Water fluoridation in 40 Brazilian cities: 7 year analysis

    Directory of Open Access Journals (Sweden)

    Suzely Adas Saliba MOIMAZ

    2013-01-01

    Full Text Available Objectives Fluoride levels in the public water supplies of 40 Brazilian cities were analyzed and classified on the basis of risk/benefit balance. Material and Methods Samples were collected monthly over a seven-year period from three sites for each water supply source. The samples were analyzed in duplicate in the laboratory of the Center for Research in Public Health - UNESP using an ion analyzer coupled to a fluoride-specific electrode. Results A total of 19,533 samples were analyzed, of which 18,847 were artificially fluoridated and 686 were not artificially fluoridated. In samples from cities performing water fluoridation, 51.57% (n=9,720 had fluoride levels in the range of 0.55 to 0.84 mg F/L; 30.53% (n=5,754 were below 0.55 mg F/L and 17.90% (n=3,373 were above 0.84 mg F/L (maximum concentration=6.96 mg F/L. Most of the cities performing fluoridation that had a majority of samples with fluoride levels above the recommended parameter had deep wells and more than one source of water supply. There was some variability in the fluoride levels of samples from the same site and between collection sites in the same city. Conclusions The majority of samples from cities performing fluoridation had fluoride levels within the range that provides the best combination of risks and benefits, minimizing the risk of dental fluorosis while preventing dental caries. The conduction of studies about water distribution systems is suggested in cities with high natural fluoride concentrations in order to optimize the use of natural fluoride for fluoridation costs and avoid the risk of dental fluorosis.

  7. Reduction of Erosive Wear in situ by Stannous Fluoride-Containing Toothpaste.

    NARCIS (Netherlands)

    Huysmans, M.C.D.N.J.M.; Jager, D.H.; Ruben, J.L.; Unk, D.E.; Klijn, C.P.; Vieira, A.M.

    2011-01-01

    Background/Aims: Stannous fluoride (SnF) has been suggested as a dental erosion-preventive agent. The aim of this single-centre, randomized, double-blind, in situ study was to evaluate the effect of toothpastes with SnF in the prevention of erosive enamel wear. Methods: A combined split-mouth

  8. Pilot-Scale Removal Of Fluoride From Legacy Plutonium Materials Using Vacuum Salt Distillation

    International Nuclear Information System (INIS)

    Pierce, R. A.; Pak, D. J.

    2012-01-01

    Between September 2009 and January 2011, the Savannah River National Laboratory (SRNL) and HB-Line designed, developed, tested, and successfully deployed a system for the distillation of chloride salts. In 2011, SRNL adapted the technology for the removal of fluoride from fluoride-bearing salts. The method involved an in situ reaction between potassium hydroxide (KOH) and the fluoride salt to yield potassium fluoride (KF) and the corresponding oxide. The KF and excess KOH can be distilled below 1000°C using vacuum salt distillation (VSD). The apparatus for vacuum distillation contains a zone heated by a furnace and a zone actively cooled using either recirculated water or compressed air. During a vacuum distillation operation, a sample boat containing the feed material is placed into the apparatus while it is cool, and the system is sealed. The system is evacuated using a vacuum pump. Once a sufficient vacuum is attaned, heating begins. Volatile salts distill from the heated zone to the cooled zone where they condense, leaving behind the non-volatile material in the feed boat. Studies discussed in this report were performed involving the use of non-radioactive simulants in small-scale and pilot-scale systems as well as radioactive testing of a small-scale system with plutonium-bearing materials. Aspects of interest include removable liner design considerations, boat materials, in-line moisture absorption, and salt deposition

  9. Fluoride salts and container materials for thermal energy storage applications in the temperature range 973 to 1400 K

    Science.gov (United States)

    Misra, Ajay K.; Whittenberger, J. Daniel

    1987-01-01

    Multicomponent fluoride salt mixtures were characterized for use as latent heat of fusion heat storage materials in advanced solar dynamic space power systems with operating temperatures in the range of 973 to 1400 K. The melting points and eutectic composition for many systems with published phase diagrams were verified, and several new eutectic compositions were identified. Additionally, the heats of fusion of several binary and ternary eutectics and congruently melting intermediate compounds were measured by differential scanning calorimetry. The extent of corrosion of various metals by fluoride melts was estimated from thermodynamic considerations, and equilibrium conditions inside a containment vessel were calculated as functions of the initial moisture content of the salt and free volume above the molten salt. Preliminary experimental data on the corrosion of commercial, high-temperature alloys in LiF-19.5CaF2 and NaF-27CaF2-36MgF2 melts are presented and compared to the thermodynamic predictions.

  10. Physiology and toxicity of fluoride

    Directory of Open Access Journals (Sweden)

    Dhar Vineet

    2009-01-01

    Full Text Available Fluoride has been described as an essential element needed for normal development and growth of animals and extremely useful for human beings. Fluoride is abundant in the environment and the main source of fluoride to humans is drinking water. It has been proved to be beneficial in recommended doses, and at the same time its toxicity at higher levels has also been well established. Fluoride gets accumulated in hard tissues of the body and has been know to play an important role in mineralization of bone and teeth. At high levels it has been known to cause dental and skeletal fluorosis. There are suggested effects of very high levels of fluoride on various body organs and genetic material. The purpose of this paper is to review the various aspects of fluoride and its importance in human life.

  11. Physiology and toxicity of fluoride.

    Science.gov (United States)

    Dhar, Vineet; Bhatnagar, Maheep

    2009-01-01

    Fluoride has been described as an essential element needed for normal development and growth of animals and extremely useful for human beings. Fluoride is abundant in the environment and the main source of fluoride to humans is drinking water. It has been proved to be beneficial in recommended doses, and at the same time its toxicity at higher levels has also been well established. Fluoride gets accumulated in hard tissues of the body and has been know to play an important role in mineralization of bone and teeth. At high levels it has been known to cause dental and skeletal fluorosis. There are suggested effects of very high levels of fluoride on various body organs and genetic material. The purpose of this paper is to review the various aspects of fluoride and its importance in human life.

  12. A health risk assessment for fluoride in Central Europe.

    Science.gov (United States)

    Fordyce, F M; Vrana, K; Zhovinsky, E; Povoroznuk, V; Toth, G; Hope, B C; Iljinsky, U; Baker, J

    2007-04-01

    Like many elements, fluorine (which generally occurs in nature as fluoride) is beneficial to human health in trace amounts, but can be toxic in excess. The links between low intakes of fluoride and dental protection are well known; however, fluoride is a powerful calcium-seeking element and can interfere with the calcified structure of bones and teeth in the human body at higher concentrations causing dental or skeletal fluorosis. One of the main exposure routes is via drinking water and the World Health Organisation currently sets water quality guidelines for the element. In Central Europe, groundwater resources that exceed the guideline value of 1.5 mg l-1 are widespread and effects on health of high fluoride in water have been reported. The aim of the current project was to develop a geographic information system (GIS) to aid the identification of areas where high-fluoride waters and fluorosis may be a problem; hence, where water treatment technologies should be targeted. The development of the GIS was based upon the collation and digitisation of existing information relevant to fluoride risk in Ukraine, Moldova, Hungary and Slovakia assembled for the first time in a readily accessible form. In addition, geochemistry and health studies to examine in more detail the relationships between high-fluoride drinking waters and health effects in the population were carried out in Moldova and Ukraine demonstrating dental fluorosis prevalence rates of 60-90% in adolescents consuming water containing 2-7 mg l-1 fluoride.

  13. Water Fluoridation: A Critical Review of the Physiological Effects of Ingested Fluoride as a Public Health Intervention

    Science.gov (United States)

    2014-01-01

    Fluorine is the world's 13th most abundant element and constitutes 0.08% of the Earth crust. It has the highest electronegativity of all elements. Fluoride is widely distributed in the environment, occurring in the air, soils, rocks, and water. Although fluoride is used industrially in a fluorine compound, the manufacture of ceramics, pesticides, aerosol propellants, refrigerants, glassware, and Teflon cookware, it is a generally unwanted byproduct of aluminium, fertilizer, and iron ore manufacture. The medicinal use of fluorides for the prevention of dental caries began in January 1945 when community water supplies in Grand Rapids, United States, were fluoridated to a level of 1 ppm as a dental caries prevention measure. However, water fluoridation remains a controversial public health measure. This paper reviews the human health effects of fluoride. The authors conclude that available evidence suggests that fluoride has a potential to cause major adverse human health problems, while having only a modest dental caries prevention effect. As part of efforts to reduce hazardous fluoride ingestion, the practice of artificial water fluoridation should be reconsidered globally, while industrial safety measures need to be tightened in order to reduce unethical discharge of fluoride compounds into the environment. Public health approaches for global dental caries reduction that do not involve systemic ingestion of fluoride are urgently needed. PMID:24719570

  14. Effect of dog food containing 460 ppm fluoride on rat reproduction.

    Science.gov (United States)

    Marks, T A; Schellenberg, D; Metzler, C M; Oostveen, J; Morey, M J

    1984-01-01

    A one-generation, two-litter rat reproduction study was done in a kennel in Allegan County, Michigan, as part of an investigation of reproductive problems in Shetland sheepdogs (shelties). Since 1970, at least 115 sheltie litters at this kennel have been grossly deformed and/or have died, generally within 3 d of birth. The causative factor(s) appears to be associated with the environment, as the shelties have had successful pregnancies elsewhere. There was some concern that a potential threat to human reproduction also might exist in this area. After it was discovered that fluoride in the dog food had apparently caused mottled teeth and bony exostoses in dogs at this and at least two other kennels, dog-food fluoride content and local well water were investigated as possible causes of the reproductive problems. A two-way factorial statistical design allowed assessment of dietary fluoride content and water source and interaction between the two. UPj:TUC(SD)spf rats, 9 males and 18 females in each group, were assigned to treatment with high-fluoride dog food (460 ppm) and well water; high-fluoride dog food and distilled water; low-fluoride dog food (56 ppm) and well water; and low-fluoride dog food and distilled water. After 60 d in the kennel, the rats were mated. Even after two litters, the only adverse effect was dental fluorosis in the high-fluoride groups. The results indicated that rats cannot be used in the search for the cause(s) of reproductive problems in dogs in this kennel.

  15. Chemico-therapeutic approach to prevention of dental caries. [using stannous fluoride gel

    Science.gov (United States)

    Shannon, I. L.

    1975-01-01

    The program of chemical preventive dentistry is based primarily upon the development of a procedure for stabilizing stannous fluoride in solution by forcing it into glycerin. New topical fluoride treatment concentrates, fluoride containing gels and prophylaxis pastes, as well as a completely stable stannous fluoride dentifrice are made possible by the development of a rather complicated heat application method to force stannous fluoride into solution in glycerin. That the stannous fluoride is clinically effective in such a preparation is demonstrated briefly on orthodontic patients.

  16. Slow-release fluoride devices for the control of dental decay.

    Science.gov (United States)

    Chong, Lee-Yee; Clarkson, Jan E; Dobbyn-Ross, Lorna; Bhakta, Smriti

    2018-03-01

    Slow-release fluoride devices have been investigated as a potentially cost-effective method of reducing dental caries in people with high risk of disease. This is the second update of the Cochrane Review first published in 2006 and previously updated in 2014. To evaluate the effectiveness and safety of different types of slow-release fluoride devices on preventing, arresting, or reversing the progression of carious lesions on all surface types of primary (deciduous) and permanent teeth. Cochrane Oral Health's Information Specialist searched the following electronic databases: Cochrane Oral Health's Trials Register (to 23 January 2018); the Cochrane Central Register of Controlled Trials (CENTRAL; 2017, Issue 12) in the Cochrane Library (searched 23 January 2018); MEDLINE Ovid (1946 to 23 January 2018); and Embase Ovid (1980 to 23 January 2018). The US National Institutes of Health Ongoing Trials Register ClinicalTrials.gov, and the World Health Organization International Clinical Trials Registry Platform were searched for ongoing trials (23 January 2018). We placed no restrictions on the language or date of publication when searching the electronic databases. Parallel randomised controlled trials (RCTs) comparing slow-release fluoride devices with an alternative fluoride treatment, placebo, or no intervention in all age groups. The main outcome measures sought were changes in numbers of decayed, missing, and filled teeth or surfaces (DMFT/DMFS in permanent teeth or dmft/dmfs in primary teeth), and progression of carious lesions through enamel and into dentine. We conducted data collection and analysis using standard Cochrane review methods. At least two review authors independently performed all the key steps in the review such as screening of abstracts, application of inclusion criteria, data extraction, and risk of bias assessment. We resolved discrepancies through discussions or arbitration by a third or fourth review author. We found no evidence comparing slow

  17. Enhancement of Saharan groundwater quality by reducing its fluoride concentration using different materials

    KAUST Repository

    Ramdani, Amina

    2014-04-15

    According to the environmental protection regulations, fluoride concentration is considered as a substance of priority for assessment of drinking water quality to determine their impacts on the environment and public health. Saharan groundwater (Algeria) contains an excess of fluoride ions. Regular consumption of this water by the population of the region may cause endemic fluorosis. To solve this problem, we propose to treat this water by adsorption on different materials, such as activated alumina (AA), sodium clay (SC), and hydroxyapatite (HAP) in order to enhance its quality by reducing its fluoride concentration. The maximum adsorption is achieved with an adsorption capacity of the order of 0.9, 0.667, and 0.370 mg/g and with a percentage of 90, 83.4, and 73.95% for AA, HAP, and SC, respectively. Indeed, the acidity and alkalinity of the medium significantly affect the adsorption of fluoride ions. Results deduced from the curves of adsorption isotherms of fluoride ions showed that the retention is predictable from these isotherms in agreement with the Langmuir model. The low removal of fluoride ions was observed in presence of (Formula presented.), (Formula presented.), and (Formula presented.) ions. Finally, AA material proved to be the best adsorbent for fluoride ions removal. © 2014 © 2014 Balaban Desalination Publications. All rights reserved.

  18. Dental Glass Ionomer Cements as Permanent Filling Materials? – Properties, Limitations and Future Trends

    Directory of Open Access Journals (Sweden)

    Ulrich Lohbauer

    2009-12-01

    Full Text Available Glass ionomer cements (GICs are clinically attractive dental materials that have certain unique properties that make them useful as restorative and luting materials. This includes adhesion to moist tooth structures and base metals, anticariogenic properties due to release of fluoride, thermal compatibility with tooth enamel, biocompatibility and low toxicity. The use of GICs in a mechanically loaded situation, however, has been hampered by their low mechanical performance. Poor mechanical properties, such as low fracture strength, toughness and wear, limit their extensive use in dentistry as a filling material in stress-bearing applications. In the posterior dental region, glass ionomer cements are mostly used as a temporary filling material. The requirement to strengthen those cements has lead to an ever increasing research effort into reinforcement or strengthening concepts.

  19. Structure-solubility relationships in fluoride-containing phosphate based bioactive glasses

    Science.gov (United States)

    Shaharyar, Yaqoot

    The dissolution of fluoride-containing bioactive glasses critically affects their biomedical applications. Most commercial fluoride-releasing bioactive glasses have been designed in the soda-lime-silica system. However, their relatively slow chemical dissolution and the adverse effect of fluoride on their bioactivity are stimulating the study of novel biodegradable materials with higher bioactivity, such as biodegradable phosphate-based bioactive glasses, which can be a viable alternative for applications where a fast release of active ions is sought. In order to design new biomaterials with controlled degradability and high bioactivity, it is essential to understand the connection between chemical composition, molecular structure, and solubility in physiological fluids.Accordingly, in this work we have combined the strengths of various experimental techniques with Molecular Dynamics (MD) simulations, to elucidate the impact of fluoride ions on the structure and chemical dissolution of bioactive phosphate glasses in the system: 10Na2O - (45-x) CaO - 45P2O5 - xCaF2, where x varies between 0 -- 10 mol.%. NMR and MD data reveal that the medium-range atomic-scale structure of thse glasses is dominated by Q2 phosphate units followed by Q1 units, and the MD simulations further show that fluoride tends to associate with network modifier cations to form alkali/alkaline-earth rich ionic aggregates. On a macroscopic scale, we find that incorporating fluoride in phosphate glasses does not affect the rate of apatite formation on the glass surface in simulated body fluid (SBF). However, fluoride has a marked favorable impact on the glass dissolution in deionized water. Similarly, fluoride incorporation in the glasses results in significant weight gain due to adsorption of water (in the form of OH ions). These macroscopic trends are discussed on the basis of the F effect on the atomistic structure of the glasses, such as the F-induced phosphate network re-polymerization, in a

  20. The association between fluoride in drinking water and dental caries in Danish children. Linking data from health registers, environmental registers and administrative registers

    DEFF Research Database (Denmark)

    Kirkeskov, Lilli; Kristiansen, Eva; Bøggild, Henrik

    2010-01-01

    Kirkeskov L, Kristiansen E, Bøggild H, von Platen-Hallermund F, Sckerl H, Carlsen A, Larsen MJ, Poulsen S. The association between fluoride in drinking water and dental caries in Danish children. Linking data from health registers, environmental registers and administrative registers. Community...... Dent Oral Epidemiol 2010. (c) 2010 John Wiley & Sons A/S Abstract - Objectives: To study the association between fluoride concentration in drinking water and dental caries in Danish children. Methods: The study linked registry data on fluoride concentration in drinking water over a 10-year period...... with data on dental caries from the Danish National Board of Health database on child dental health for 5-year-old children born in 1989 and 1999, and for 15-year-old children born in 1979 and 1989. The number of children included in the cohorts varied between 41.000 and 48.000. Logistic regression was used...

  1. The cariostatic mechanisms of fluoride

    Directory of Open Access Journals (Sweden)

    Kata Rošin-Grget

    2013-11-01

    Full Text Available This article discusses the possible cariostatic mechanisms of the action of fluoride. In the past, fluoride inhibition of caries was ascribed to reduced solubility of enamel due to incorporation of fluoride (F– into the enamel minerals. The present evidence from clinical and laboratory studies suggests that the caries-preventive mode of action of fluoride is mainly topical. There is convincing evidence that fluoride has a major effect on demineralisation and remineralisation of dental hard tissue. The source of this fluoride could either be fluorapatite (formed due to the incorporation of fluoride into enamel or calcium fluoride (CaF2-like precipitates, which are formed on the enamel and in the plaque after application of topical fluoride. Calcium fluoride deposits are protected from rapid dissolution by a phosphate –protein coating of salivary origin. At lower pH, the coating is lost and an increased dissolution rate of calcium fluoride occurs. The CaF2, therefore, act as an efficient source of free fluoride ions during the cariogenic challenge. The current evidence indicates that fluoride has a direct and indirect effect on bacterial cells, although the in vivo implications of this are still not clear. Conclusion. A better understanding of the mechanisms of the action of fluoride is very important for caries prevention and control. The effectiveness of fluoride as a cariostatic agent depends on the availability of free fluoride in plaque during cariogenic challenge, i.e. during acid production. Thus, a constant supply of low levels of fluoride in biofilm/saliva/dental interference is considered the most beneficial in preventing dental caries.

  2. The cariostatic mechanisms of fluoride.

    Science.gov (United States)

    Rošin-Grget, Kata; Peroš, Kristina; Sutej, Ivana; Bašić, Krešimir

    2013-11-01

    This article discusses the possible cariostatic mechanisms of the action of fluoride. In the past, fluoride inhibition of caries was ascribed to reduced solubility of enamel due to incorporation of fluoride (F-) into the enamel minerals. The present evidence from clinical and laboratory studies suggests that the caries-preventive mode of action of fluoride is mainly topical. There is convincing evidence that fluoride has a major effect on demineralisation and remineralisation of dental hard tissue. The source of this fluoride could either be fluorapatite (formed due to the incorporation of fluoride into enamel) or calcium fluoride (CaF2)-like precipitates, which are formed on the enamel and in the plaque after application of topical fluoride. Calcium fluoride deposits are protected from rapid dissolution by a phosphate -protein coating of salivary origin. At lower pH, the coating is lost and an increased dissolution rate of calcium fluoride occurs. The CaF2, therefore, act as an efficient source of free fluoride ions during the cariogenic challenge. The current evidence indicates that fluoride has a direct and indirect effect on bacterial cells, although the in vivo implications of this are still not clear. A better understanding of the mechanisms of the action of fluoride is very important for caries prevention and control. The effectiveness of fluoride as a cariostatic agent depends on the availability of free fluoride in plaque during cariogenic challenge, i.e. during acid production. Thus, a constant supply of low levels of fluoride in biofilm/saliva/dental interference is considered the most beneficial in preventing dental caries. Copyright © 2013 by Academy of Sciences and Arts of Bosnia and Herzegovina.

  3. Fluoride mouthrinses for preventing dental caries in children and adolescents.

    Science.gov (United States)

    Marinho, Valeria C C; Chong, Lee Yee; Worthington, Helen V; Walsh, Tanya

    2016-07-29

    Fluoride mouthrinses have been used extensively as a caries-preventive intervention in school-based programmes and by individuals at home. This is an update of the Cochrane review of fluoride mouthrinses for preventing dental caries in children and adolescents that was first published in 2003. The primary objective is to determine the effectiveness and safety of fluoride mouthrinses in preventing dental caries in the child and adolescent population.The secondary objective is to examine whether the effect of fluoride rinses is influenced by:• initial level of caries severity;• background exposure to fluoride in water (or salt), toothpastes or reported fluoride sources other than the study option(s); or• fluoride concentration (ppm F) or frequency of use (times per year). We searched the following electronic databases: Cochrane Oral Health's Trials Register (whole database, to 22 April 2016), the Cochrane Central Register of Controlled Trials (CENTRAL) (the Cochrane Library, 2016, Issue 3), MEDLINE Ovid (1946 to 22 April 2016), Embase Ovid (1980 to 22 April 2016), CINAHL EBSCO (the Cumulative Index to Nursing and Allied Health Literature, 1937 to 22 April 2016), LILACS BIREME (Latin American and Caribbean Health Science Information Database, 1982 to 22 April 2016), BBO BIREME (Bibliografia Brasileira de Odontologia; from 1986 to 22 April 2016), Proquest Dissertations and Theses (1861 to 22 April 2016) and Web of Science Conference Proceedings (1990 to 22 April 2016). We undertook a search for ongoing trials on the US National Institutes of Health Trials Register (http://clinicaltrials.gov) and the World Health Organization International Clinical Trials Registry Platform. We placed no restrictions on language or date of publication when searching electronic databases. We also searched reference lists of articles and contacted selected authors and manufacturers. Randomised or quasi-randomised controlled trials where blind outcome assessment was stated or

  4. Fluoride and Oral Health.

    Science.gov (United States)

    O'Mullane, D M; Baez, R J; Jones, S; Lennon, M A; Petersen, P E; Rugg-Gunn, A J; Whelton, H; Whitford, G M

    2016-06-01

    The discovery during the first half of the 20th century of the link between natural fluoride, adjusted fluoride levels in drinking water and reduced dental caries prevalence proved to be a stimulus for worldwide on-going research into the role of fluoride in improving oral health. Epidemiological studies of fluoridation programmes have confirmed their safety and their effectiveness in controlling dental caries. Major advances in our knowledge of how fluoride impacts the caries process have led to the development, assessment of effectiveness and promotion of other fluoride vehicles including salt, milk, tablets, toothpaste, gels and varnishes. In 1993, the World Health Organization convened an Expert Committee to provide authoritative information on the role of fluorides in the promotion of oral health throughout the world (WHO TRS 846, 1994). This present publication is a revision of the original 1994 document, again using the expertise of researchers from the extensive fields of knowledge required to successfully implement complex interventions such as the use of fluorides to improve dental and oral health. Financial support for research into the development of these new fluoride strategies has come from many sources including government health departments as well as international and national grant agencies. In addition, the unique role which industry has played in the development, formulation, assessment of effectiveness and promotion of the various fluoride vehicles and strategies is noteworthy. This updated version of 'Fluoride and Oral Health' has adopted an evidence-based approach to its commentary on the different fluoride vehicles and strategies and also to its recommendations. In this regard, full account is taken of the many recent systematic reviews published in peer reviewed literature.

  5. Pit and fissure sealants versus fluoride varnishes for preventing dental decay in children and adolescents

    DEFF Research Database (Denmark)

    Hiiri, Anne; Ahovuo-Saloranta, Anneli; Nordblad, Anne

    2010-01-01

    the effectiveness of pit and fissure sealants to be statistically significantly higher than an application of fluoride varnish every 6 months in preventing occlusal decays of first molars at 23 months (with a RR of 0.74, 95% confidence interval (CI) 0.58 to 0.95); and at 4 years and 9 years (with a RR of 0.42, 95...... caries on the fluoride varnished tooth surfaces, compared to sealed plus fluoride varnished surfaces, with a RR of 0.36 (95% CI 0.21 to 0.61). AUTHORS' CONCLUSIONS: There was some evidence on the superiority of pit and fissure sealants over fluoride varnish application in the prevention of occlusal......BACKGROUND: The majority of the detected increment in dental caries among children and adolescents is confined to pit and fissure surfaces of first molars. OBJECTIVES: The objective of this study was to compare the effectiveness of pit and fissure sealants with fluoride varnishes in the prevention...

  6. Parental views on fluoride tooth brushing and its impact on oral health: A cross-sectional study.

    Science.gov (United States)

    Alshehri, Mohammad; Kujan, Omar

    2015-01-01

    This study aimed to describe the current use and knowledge about fluoride toothpaste and children's oral hygiene habits among parents of Saudi children. In this cross-sectional study, the parents of children aged 7-12 years who visited the undergraduate pediatric dental clinics at the College of Dentistry in Riyadh, Saudi Arabia were interviewed. The interview included questions to assess the parents' level of fluoride knowledge, the dental appearance of their children, and any general dental health concerns and practices. A total of 463 parents (women 55.5%, men 44.5%) were included. Over half (60.3%) of the participants reported that they were unhappy with the appearance of their child's teeth. Only 11.5% received high fluoride knowledge scores. The additive index for the level of fluoride knowledge was significantly lower among mothers than among fathers. The majority of the parents were not able to correctly report whether the toothpaste their children used contained fluoride. Furthermore, the majority of the respondents were unaware of the benefits of fluoride in preventing dental caries. There is a need to enhance parental knowledge regarding high fluoride intake and its harmful consequences on children's health. Both mothers and fathers should have higher levels of awareness regarding oral health promotion to maintain optimal oral health in their children.

  7. Prevalence of dental fluorosis in children taking part in an oral health programme including fluoride tablet supplements from the age of 2 years

    DEFF Research Database (Denmark)

    Eckersten, Charlotte; Pylvänen, Lena; Schröder, Ulla

    2010-01-01

    To investigate the prevalence of dental fluorosis in children who had participated in an oral health programme between the ages 2-5 years, including fluoride tablets from the age of 2 years.......To investigate the prevalence of dental fluorosis in children who had participated in an oral health programme between the ages 2-5 years, including fluoride tablets from the age of 2 years....

  8. Fluoride toothpaste containing 1.5% arginine and insoluble calcium as a new standard of care in caries prevention

    NARCIS (Netherlands)

    ten Cate, J.M.; Cummins, D.

    2013-01-01

    In spite of obvious achievements in prevention, caries remains a prevalent disease. Fluorides are effective by inhibiting enamel and dentin demineralization and enhancing remineralization, but have little or no influence on bacterial processes in dental plaque. Dental caries is a continuum of stages

  9. Loss on drying, calcium concentration and pH of fluoride dentifrices

    Directory of Open Access Journals (Sweden)

    Arella Cristina Muniz Brito

    2015-01-01

    Full Text Available Introduction: Fluoride dentifrices containing calcium carbonate have advantages such as control of dental plaque and progression of dental caries, also contributing to oral hygiene, represent most dentifrices marketed in Brazil. Aim: To evaluate the physicochemical properties of seven fluoride dentifrices containing calcium carbonate in relation to hydrogen potential (pH, loss on drying and calcium concentration. Materials and Methods: Data collection was performed using the potentiometric method for pH ranges, gravimetric analysis for loss on drying and atomic absorption spectrometry for the concentration of calcium ions. All tests were performed in triplicate and the analysis was performed entirely at random according to one-way analysis of variance at 5% significance level. Results: The pH values were alkaline and ranged from 8.67 (Oral-B 123® to 10.03 (Colgate Mαxima Proteηγo Anticαries® . The results of loss on drying ranged from 33.81% (Oral-B 123® to 61.13% (Close Up® , with significant differences between brands tested. In relation to the calcium content, the highest and lowest concentrations were found in dentifrices Even® (155.55 g/kg and Colgate Ultra Branco® (129 g/kg, respectively, with significant difference (P < 0.05. Conclusion: Fluoride dentifrices analyzed showed alkaline pH and high levels of loss on drying and calcium concentration. However, these physicochemical characteristics differed according to the different brands tested.

  10. Effect of pH and fluoride on behavior of dental ZrO2 ceramics in artificial saliva

    International Nuclear Information System (INIS)

    Mukaeda, L.E.; Robin, A.; Santos, C.; Taguchi, S.P.; Borges Junior, L.A.

    2009-01-01

    A considerable increase in the ceramic products demand occurred due to the evolution of dental restoration techniques and these materials must resist to the complex mouth environment. The pH of saliva can decrease significantly due to the ingestion of acidic foods and beverages and mainly due to reactions occurring during bacteria metabolism that lead to the formation of organic acids. Fluorides are also present in the mouth since fluorides are usually added in drinking water, mouth washes, tooth pastes and gels for the prevention of plaque and caries formation. The combination of low pH and presence of fluorides can lead to the formation of HF and HF 2 - which are detrimental to metallic and probably to ceramic devices. In this work, commercial blocks of ZrO 2 ceramics (ProtMat Materiais Avancados® and Ivoclar®) were immersed in Fusayama artificial saliva of different pHs and fluoride concentrations. The properties of the as-produced ceramics (crystalline phases (XRD), microstructure (SEM), roughness (3D surface topography AFM) and mechanical resistance - Vickers hardness (Hv) and fracture toughness (KIC) were evaluated. Some of these properties were also determined after the immersion tests as well as the mass variation of the samples in order to evaluate the resistance of these ZrO 2 ceramics to degradation under these conditions. (author)

  11. Evaluation of caries progression in dentin treated by fluoride-containing materials using an in-air micro-PIGE and micro-PIXE measurement system

    Energy Technology Data Exchange (ETDEWEB)

    Yamamoto, H., E-mail: yhiroko@dent.osaka-u.ac.jp [Department of Restorative Dentistry and Endodontology, Osaka University Graduate School of Dentistry, 1-8 Yamada-Oka, Suita 565-0871 (Japan); Iwami, Y.; Yagi, K.; Hayashi, M. [Department of Restorative Dentistry and Endodontology, Osaka University Graduate School of Dentistry, 1-8 Yamada-Oka, Suita 565-0871 (Japan); Komatsu, H.; Okuyama, K.; Matsuda, Y. [Graduate School of Dental Medicine, Hokkaido University, Kita 13, Nishi 7, Kita-ku, Sapporo 060-8586 (Japan); Yasuda, K. [The Wakasa Wan Energy Research Center, 64-52-1 Nagatani, Tsuruga 914-0192 (Japan)

    2015-04-01

    It is well-known that fluorine (F) is involved in the progression of caries. The evaluation of caries progression has conventionally been based on the change in mineral content using transverse microradiography (TMR). The purpose of this study was to evaluate the progression of dentinal caries by the change in calcium (Ca) content using Particle-Induced Gamma-ray Emission/Particle-Induced X-ray Emission (PIGE/PIXE) techniques at the Wakasa Wan Energy Research Center. We also assessed the relationship between caries progression rate and the concentration of F penetration into dentin from dental fluoride-containing materials (FCMs). Dentin sections of six extracted human teeth were prepared to obtain various amounts of F uptake using three types of FCMs. F and Ca distribution of specimens were obtained using PIGE/PIXE techniques. After evaluation, the specimens were immersed in 10 ml of demineralizing solution (pH 4.5) to simulate caries attack. To estimate caries progression rates, the same portions of the specimens were evaluated after caries attack treatment using PIGE/PIXE. A negative correlation between the F uptake in dentin and the rate of caries progression was observed. Therefore, caries progression in dentin was reduced by increasing the amount of F uptake from FCMs. This demonstrates that PIGE/PIXE techniques are valuable for estimating caries progression rates.

  12. Evaluation of caries progression in dentin treated by fluoride-containing materials using an in-air micro-PIGE and micro-PIXE measurement system

    International Nuclear Information System (INIS)

    Yamamoto, H.; Iwami, Y.; Yagi, K.; Hayashi, M.; Komatsu, H.; Okuyama, K.; Matsuda, Y.; Yasuda, K.

    2015-01-01

    It is well-known that fluorine (F) is involved in the progression of caries. The evaluation of caries progression has conventionally been based on the change in mineral content using transverse microradiography (TMR). The purpose of this study was to evaluate the progression of dentinal caries by the change in calcium (Ca) content using Particle-Induced Gamma-ray Emission/Particle-Induced X-ray Emission (PIGE/PIXE) techniques at the Wakasa Wan Energy Research Center. We also assessed the relationship between caries progression rate and the concentration of F penetration into dentin from dental fluoride-containing materials (FCMs). Dentin sections of six extracted human teeth were prepared to obtain various amounts of F uptake using three types of FCMs. F and Ca distribution of specimens were obtained using PIGE/PIXE techniques. After evaluation, the specimens were immersed in 10 ml of demineralizing solution (pH 4.5) to simulate caries attack. To estimate caries progression rates, the same portions of the specimens were evaluated after caries attack treatment using PIGE/PIXE. A negative correlation between the F uptake in dentin and the rate of caries progression was observed. Therefore, caries progression in dentin was reduced by increasing the amount of F uptake from FCMs. This demonstrates that PIGE/PIXE techniques are valuable for estimating caries progression rates

  13. Control of Established Gingivitis and Dental Plaque Using a 1450 ppm Fluoride/Zinc-based Dentifrice: A Randomized Clinical Study.

    Science.gov (United States)

    Zhong, Y; Li, X; Hu, D Y; Mateo, L R; Morrison, B M; Delgado, E; Zhang, Y P

    2015-01-01

    To investigate the clinical efficacy in controlling established gingivitis and dental plaque of a 1450 ppm fluoride as sodium monofluorophosphate (SMFP)/zinc-based dentifrice, as compared to a zinc-free dentifrice with 1450 ppm fluoride as SMFP after six months product use. A six-month clinical study, with eighty-six (86) subjects, was conducted in Chengdu, China, using a double-blind, randomized, parallel-group treatment design. After a baseline evaluation, study subjects were randomly assigned to one of the two study treatments: 1) 1450 ppm fluoride as SMFP/zinc-based dentifrice (Test) or 2) 1450 ppm fluoride as SMFP/zinc-free dentifrice (Negative Control). Subjects were provided with a soft bristle toothbrush and brushed their teeth twice daily (morning and evening) for one minute with their assigned dentifrice. After three months, and again after six months of product use, subjects returned to the testing facility for their followup gingivitis and plaque examinations. Statistical analyses were performed separately for the gingivitis assessments and dental plaque assessments using the appropriate statistical methods. All statistical tests of hypotheses were two-sided, and employed a level of significance of α = 0.05. After three and six months of product use, subjects assigned to the Test treatment exhibited statistically significant (p gingival index and plaque index scores as compared to subjects assigned to the Negative Control treatment. The results of this single-center, double-blind, parallel-group and randomized clinical study support the conclusion that a 1450 ppm fluoride as SMFP/zinc-based dentifrice provides clinically meaningful and statistically significant reductions in gingivitis (23.8%) and dental plaque (22.5%) as compared to a 1450 ppm fluoride as SMFP/zinc-free dentifrice over a six-month period of twice-daily product use.

  14. Fluoride removal studies in water using natural materials : technical ...

    African Journals Online (AJOL)

    Excess fluoride in water causes health hazards to the natural environment. The removal of fluoride was attempted using natural materials such as red soil, charcoal, brick, fly-ash and serpentine. Each material was set up in a column for a known volume and the defluoridation capacities of these materials were studied with ...

  15. Primary prevention of dental erosion by calcium and fluoride: a systematic review.

    Science.gov (United States)

    Zini, A; Krivoroutski, Y; Vered, Y

    2014-02-01

    Overviews of the current literature only provide summaries of existing relevant preventive strategies for dental erosion. To perform a systematic review according to the quantitative meta-analysis method of the scientific literature on prevention of dental erosion. The focused question will address primary prevention of dental erosion by calcium and fluoride. Randomized clinical trials (RCTs) regarding dental erosion prevention. The search included five databases: Embase, Cochrane database of systematic reviews, PubMed (MEDLINE), FDA publication and Berman medical library of the Hebrew University. The search included data in the English language, with effect on preventing dental erosion always presented as mean enamel loss and measured by profilometer. Statistical meta-analysis was performed by StatsDirect program and PEPI statistical software. Fixed- and random-effect models were used to analyse the data. Heterogeneity tests were employed to validate the fixed-effect model assumption. A total of 475 articles on dental erosion prevention were located. A four-stage selection process was employed, and 10 RCT articles were found to be suitable for meta-analysis. The number of studies on prevention of dental erosion maintaining standards of evidence-based dentistry remains insufficient to reach any definite conclusions. The focused questions of this review cannot be addressed according to the existing literature. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  16. Comparison of Fluoride Content in Drinking Water and Prevalence of Dental Fluorosis in 6 - 12-Year-Old Students in Mariwan (a Cold Region and Behbahan (a Warm Region during the 2013 - 2014 Educational Year

    Directory of Open Access Journals (Sweden)

    Rezvan Rafatjou

    2016-07-01

    Full Text Available Background Fluoride plays an important role in preventing dental caries. Low fluoride concentrations cannot prevent dental caries, but ingestion of very high concentrations of fluoride during enamel development and maturation could lead to fluorosis. Fluoridation of drinking water is the most effective and inexpensive method for preventing caries. The mandated concentration of fluoride incorporated into drinking water should consider the mean temperature of each region. Objectives The aim of the present study was to evaluate the prevalence of fluorosis in children aged 6 - 12 in Mariwan and Behbahan and determine the fluoride content of drinking water in these two towns. Materials and Methods In the present descriptive and cross-sectional study, 13 water samples were taken from homes in Behbahan, 1 sample from the town’s water reservoir, 10 samples from homes in Mariwan (5 samples for each reservoir and 1 sample each from the town’s 2 reservoirs. The 26 samples (23 from homes and 3 from reservoirs were taken in polyethylene containers. The SPANDS colorimetric technique was used to determine fluoride content. Homes that used home-based water purification systems were excluded from the study. In addition, 128 students (62 girls and 66 boys in Behbahan and 90 students in Mariwan were randomly selected. Dean’s index was used to determine dental fluorosis. The mean yearly temperatures of the two towns were obtained from the metrological bureaus of the two towns. Results The means fluoride content of water in Behbahan’s reservoir and Mariwan’s reservoirs 1 and 2 were 0.7, 0.24 and 0.036 ppm, respectively. The mean fluoride content of Behbahan’s home waterlines and in the relevant home waterlines of reservoirs 1 and 2 in Mariwan were 0.67, 0.218, and 0.054 ppm, respectively. There were no significant differences between the relevant reservoirs. The prevalence of fluorosis in Behbahan was as follows: 84.4% healthy, 10.9% questionable, 1

  17. Effect of pH and fluoride on behavior of dental ZrO{sub 2} ceramics in artificial saliva

    Energy Technology Data Exchange (ETDEWEB)

    Mukaeda, L.E.; Robin, A.; Santos, C.; Taguchi, S.P.; Borges Junior, L.A., E-mail: luizamukaeda@gmail.com, E-mail: alain@demar.eel.usp.br, E-mail: claudinei@demar.eel.usp.br, E-mail: simone@demar.eel.usp.br, E-mail: borges.jr@itelefonica.com.br [Universidade de Sao Paulo (EEL/DEMAR/USP), Lorena, SP (Brazil). Escola de Engenharia; Machado, J.P.B., E-mail: joaopaulo@las.inpe.br [Instituto Nacional de Pesquisas Espaciais (INPE), Sao Jose dos Campos, SP (Brazil)

    2009-07-01

    A considerable increase in the ceramic products demand occurred due to the evolution of dental restoration techniques and these materials must resist to the complex mouth environment. The pH of saliva can decrease significantly due to the ingestion of acidic foods and beverages and mainly due to reactions occurring during bacteria metabolism that lead to the formation of organic acids. Fluorides are also present in the mouth since fluorides are usually added in drinking water, mouth washes, tooth pastes and gels for the prevention of plaque and caries formation. The combination of low pH and presence of fluorides can lead to the formation of HF and HF{sub 2}{sup -} which are detrimental to metallic and probably to ceramic devices. In this work, commercial blocks of ZrO{sub 2} ceramics (ProtMat Materiais Avancados® and Ivoclar®) were immersed in Fusayama artificial saliva of different pHs and fluoride concentrations. The properties of the as-produced ceramics (crystalline phases (XRD), microstructure (SEM), roughness (3D surface topography AFM) and mechanical resistance - Vickers hardness (Hv) and fracture toughness (KIC) were evaluated. Some of these properties were also determined after the immersion tests as well as the mass variation of the samples in order to evaluate the resistance of these ZrO{sub 2} ceramics to degradation under these conditions. (author)

  18. Purification method for calcium fluoride containing uranium

    International Nuclear Information System (INIS)

    Ogami, Takeshi

    1998-01-01

    Calcium fluoride (CaF 2 ) containing uranium is heated in an electrolytic bath having a cathode and an anode to form a molten salt, and the molten salt is electrolytically reduced to form metal uranium deposited on the surface of the cathode. The calcium fluoride molten salt separated by the deposition of generated metal uranium on the surface of the cathode is solidified by cooling. The solidified calcium fluoride is recovered. When metal uranium is deposited on the surface of the cathode by the electrolytic reduction of the molten salt, impurities such as plutonium and neptunium are also deposited on the surface of the anodes entrained by the metal uranium. Impurities having high vapor pressures such as americium and strontium are evaporated and removed from the molten salts. Then, nuclides such as uranium can thus be separated and recovered, and residual CaF 2 can be recovered in a state easily storable and reutilizable. (T.M.)

  19. Effectiveness of Fluoride Varnish Application as Cariostatic and Desensitizing Agent in Irradiated Head and Neck Cancer Patients

    Directory of Open Access Journals (Sweden)

    Kanchan P. Dholam

    2013-01-01

    Full Text Available Objective. To evaluate the effectiveness of three-month fluoride varnish application on radiation caries and dental sensitivity and to assess compliance to three-month fluoride varnish application. Materials and Methods. 190 irradiated head and neck cancer patients were randomly selected and reviewed retrospectively. Oral prophylaxis, fluoride varnish application, and treatment of dental caries were done prior to radiation therapy. Patients were followed up at every three months for dental evaluation and fluoride varnish application. Decayed-missing-filling-teeth indices, dental sensitivity, and compliance to fluoride varnish application were noted for fifteen months and analyzed statistically. Results. Significant increase in decayed-missing-filling-teeth index was seen at nine (P=0.028, twelve (P=0.003 and fifteen (P=0.002 months follow-up. However, the rate of increase in decayed-missing-filling-teeth indices was 1.64/month which is less than the rate mentioned in the literature (2.5/month. There was no significant effect of sex (P=0.952 and surgery (P=0.672 on radiation caries, but site of disease (P=0.038 and radiation dose (P=0.015 were found to have statistically significant effect. Dental sensitivity decreased from 39% at 3 months to 25% at 15 months followup. 99% compliance to fluoride varnish application was seen till six months followup which decreased to 46% at fifteen months. Conclusion. Three-month fluoride varnish application is effective in decreasing radiation caries and sensitivity and has good compliance.

  20. Factors Associated with Dental Caries in Primary Dentition in a Non-Fluoridated Rural Community of New South Wales, Australia.

    Science.gov (United States)

    Arora, Amit; Manohar, Narendar; John, James Rufus

    2017-11-23

    Dental caries persists as one of the most prevalent chronic diseases among children worldwide. This study aims to determine factors that influence dental caries in primary dentition among primary school children residing in the rural non-fluoridated community of Lithgow, New South Wales, Australia. A total of 495 children aged 5-10 years old from all the six primary schools in Lithgow were approached to participate in a cross-sectional survey prior to implementation of water fluoridation in 2014. Following parental consent, children were clinically examined for caries in their primary teeth, and parents were requested to complete a questionnaire on previous fluoride exposure, diet and relevant socio-demographic characteristics that influence oral health. Multiple logistic regression analysis was employed to examine the independent risk factors of primary dentition caries. Overall, 51 percent of children had dental caries in one or more teeth. In the multiple logistic regression analysis, child's age (Adjusted Odd's Ratio (AOR) = 1.30, 95% CI: 1.14-1.49) and mother's extraction history (AOR = 2.05, 95% CI: 1.40-3.00) were significantly associated with caries experience in the child's primary teeth. In addition, each serve of chocolate consumption was associated with 52 percent higher odds (AOR = 1.52, 95% CI: 1.19-1.93) of primary dentition caries.

  1. Effect of various rinsing protocols after use of amine fluoride/stannous fluoride toothpaste on the bacterial composition of dental plaque.

    Science.gov (United States)

    van Loveren, C; Gerardu, V A M; Sissons, C H; van Bekkum, M; ten Cate, J M

    2009-01-01

    This clinical study evaluated the effect of different oral hygiene protocols on the bacterial composition of dental plaque. After a 2-week period of using fluoride-free toothpaste, 30 participants followed three 1-week experimental protocols, each followed by 2-week fluoride-free washout periods in a randomized crossover examiner-blind controlled trial. The 1-week experimental protocols comprised the use of AmF/SnF(2) toothpaste twice daily, after which participants either (1) rinsed with tap water, (2) did not rinse but only spat out the toothpaste, or (3) rinsed with an AmF/SnF(2) mouthwash. In the fluoride-free washout periods, the participants brushed their teeth with fluoride-free toothpaste without further instructions. Six hours after the last brushing (+/- rinsing) of each period, buccal plaque samples in the upper molar region were taken. The microbiota composition of the plaque samples was analyzed by checkerboard DNA:DNA hybridization. A statistically significant reduction was found in the total amount of DNA of the 39 major plaque species measured, and in the proportions of some acid-producing bacterial strains after the period having used the AmF/SnF(2) toothpaste + AmF/SnF(2) mouthrinsing. The results indicate that using the AmF/SnF(2) toothpaste and rinse combination could result in plaque of lower cariogenicity. Copyright 2009 S. Karger AG, Basel.

  2. Process for surface treatment of zirconium-containing cladding materials for fuel element or other components for nuclear reactors

    International Nuclear Information System (INIS)

    Videm, K.G.; Lunde, L.R.; Kooyman, H.H.

    1975-01-01

    A process for the surface treatment of zirconium-base cladding materials for fuel elements or other components for nuclear reactors is described. The treatment includes pickling the cladding material in a fluoride-containing bath, and then applying a protective coating through oxidation to the pickled cladding material. The fluoride-containing contaminants which remain on the surface of the cladding material during pickling are removed or rendered harmless by anodic oxidation

  3. Daya antibakteri obat kumur chlorhexidine, povidone iodine, fluoride suplementasi zinc terhadap, Streptococcus mutans dan Porphyromonas gingivalis (Antibacterial effect of mouth washes containing chlorhexidine, povidone iodine, fluoride plus zinc on Strep

    Directory of Open Access Journals (Sweden)

    Betadion Rizki Sinaredi

    2014-12-01

    Full Text Available Background: Dental Caries and periodontal disease prevalence in Indonesian children are still high. Some efforts can be done to overcome the problem; one of them is the use of mouthwash to decrease pathogen microorganisms. The mouthwashes that commercially available in market are chlorhexidine, povidone Iodine and Fluoride with Zinc supplementation. Purpose: The purpose of this study was to examine the anti bacterial effect of the mouthwashes chlorhexidine, povidone iodine and fluoride with zinc supplementation against mix bacteria that found in the plaque, Streptococcus mutans and Porphyromonas gingivalis. Methods: The antibacterial effect was measured using disk diffusion test. The bacteria samples (plaque polybacteria, S.mutans and P. gingivalis were inoculated and spread in the petridish containing MHA. Paper discs containing the mouthwashes were placed in the petridish and incubated for 24 hours at 37oC (anaerobe for P. gingivalis, aerobe for S. mutans and polybacteria. The diameter of inhibition zone surrounding the paper discs were measured and compared between each active ingredient contained in mouthwash. Results: Chlorhexidine had the strongest antibacterial effect than povidone iodine and fluoride. Chlorhexidine was more effective to inhibited the growth of S. mutans than to polybacteria or P.Gingivalis, while Povidone iodine and fluoride were more effective to inhibited the growth of polybacteria. Conclusion: The mouthwash chlorhexidine was more effective to inhibit the growth of plaque polybacteria, Streptoccous mutans and Porphyromonas gingivalis compared with povidone iodine and fluoride with zinc supplementation.Latar belakang: Prevalensi karies gigi dan penyakit periodontal masih tinggi pada anak Indonesia. Usaha mengatasi hal tersebut antara lain melalui melalui penggunaan obat kumur untuk mengurangi jumlah kuman pathogen. Kandungan obat kumur yang beredar di pasar diantaranya adalah chlorhexidine, povidone iodine dan fluoride

  4. The effective use of fluorides in public health

    DEFF Research Database (Denmark)

    Jones, Sheila; Burt, Brian A; Petersen, Poul Erik

    2005-01-01

    , systematic reviews summarizing these extensive databases have indicated that water fluoridation and fluoride toothpastes both substantially reduce the prevalence and incidence of dental caries. We present four case studies that illustrate the use of fluoride in modern public health practice, focusing on......Dental caries remain a public health problem for many developing countries and for underprivileged populations in developed countries. This paper outlines the historical development of public health approaches to the use of fluoride and comments on their effectiveness. Early research...

  5. Properties of sodium borosilicate glasses/Al2O3 sintered composites containing fluorides. Gan Fukkabutsu hokei san natoriumu garasu to alumina fukugo shoketsutai no bussei

    Energy Technology Data Exchange (ETDEWEB)

    Ryu, Bonggi; Yasui, I [The Univ. of Tokyo, Tokyo (Japan). Inst. of Industrial Science

    1993-06-01

    Glass/alumina sintered composites were synthesized from sodium borosilicate glass powder containing fluorides like AlF3 and NaF3, and Al2O3, and change in material properties was examined. Glass compositions of B2O3 and Na2O greatly affected the crystal phase and material properties. Nephelin crystal phase was extracted by the reaction of Na2O, NaF2, SiO2 and Al2O3 when B/Na<1. Coefficient of thermal expansion increased with the increase of Na/Si ratio. The residual amount of fluorides of sintered materials in nitrogen atmosphere was higher than that of air, and differed with the type of fluoride. The F[sup -] of NaF is bonded with Si of glass network and forms quiet stable glass structure, whereas, F[sup -] of AlF3 reacts with Si[sup 4+] forming SiF4 which is vaporized. Sintering temperature and dielectric constant of sintered materials containing fluoride was lower than the sintered materials without fluorides addition, however, at a sintering temperature range of 100 to 150[degree]C, it was inferred that this was because of the increase in voids due to SiF4 formed in the reaction. 16 refs., 17 figs., 3 tabs.

  6. The cariostatic mechanisms of fluoride

    OpenAIRE

    Kata Rošin-Grget; Kristina Peroš; Ivana Šutej; Krešimir Bašić

    2013-01-01

    This article discusses the possible cariostatic mechanisms of the action of fluoride. In the past, fluoride inhibition of caries was ascribed to reduced solubility of enamel due to incorporation of fluoride (F–) into the enamel minerals. The present evidence from clinical and laboratory studies suggests that the caries-preventive mode of action of fluoride is mainly topical. There is convincing evidence that fluoride has a major effect on demineralisation and remineralisation of dental hard t...

  7. Fluoride resistance in Streptococcus mutans

    NARCIS (Netherlands)

    Liao, Ying

    2017-01-01

    Fluoride has been used as the most effective anti-caries agent for over five decades. It functions not only on the dental hard tissues, but also as an antimicrobial agent. It is known that oral bacteria are able to develop resistance to fluoride, which may affect the effectiveness of fluoride in

  8. Urinary fluoride as a monitoring tool for assessing successful intervention in the provision of safe drinking water supply in five fluoride-affected villages in Dhar district, Madhya Pradesh, India.

    Science.gov (United States)

    Srikanth, R; Gautam, Anil; Jaiswal, Suresh Chandra; Singh, Pavitra

    2013-03-01

    Endemic fluorosis was detected in 31 villages in the Dhar district of Madhya Pradesh, Central India. Out of the 109 drinking water sources that were analyzed, about 67 % were found to contain high concentration of fluoride above the permissible level of 1.0 mg/l. Dental fluorosis among the primary school children in the age between 8 and 15 served as primary indicator for fluoride intoxication among the children. Urinary fluoride levels among the adults were found to be correlated with drinking water fluoride in 10 villages affected by fluoride. Intervention in the form of alternate safe water supply in five villages showed significant reduction in the urinary fluoride concentration when compared to the control village. Urinary fluoride serves as an excellent marker for assessing the effectiveness of intervention program in the fluoride-affected villages.

  9. The development and validation of a new technology, based upon 1.5% arginine, an insoluble calcium compound and fluoride, for everyday use in the prevention and treatment of dental caries.

    Science.gov (United States)

    Cummins, D

    2013-08-01

    This paper briefly discusses caries prevalence, the multi-factorial nature of caries etiology, caries risk and the role and efficacy of fluoride. The paper also highlights research on bacterial metabolism which provided understanding of the mouth's natural defenses against caries and the basis for the development of a new technology for the everyday prevention and treatment of caries. Finally, evidence that the technology complements and enhances the anti-caries efficacy of fluoride toothpaste is summarized. Global data show that dental caries is a prevalent disease, despite the successful introduction of fluoride. Caries experience depends on the balance between consumption of sugars and oral hygiene and the use of fluoride. Three scientific concepts are fundamental to new measures to detect, treat and monitor caries: (1) dental caries is a dynamic process, (2) dental caries is a continuum of stages from reversible, pre-clinical to irreversible, clinically detectable lesions, and (3) the caries process is a balance of pathological and protective factors that can be modulated to manage caries. Fluoride functions as a protective factor by arresting and reversing the caries process, but fluoride does not prevent pathological factors that initiate the process. A novel technology, based upon arginine and an insoluble calcium compound, has been identified which targets dental plaque to prevent initiation of the caries process by reducing pathological factors. As the mechanisms of action of arginine and fluoride are highly complementary, a new dentifrice, which combines arginine with fluoride, has been developed and clinically proven to provide superior caries prevention. Copyright © 2013 Elsevier Ltd. All rights reserved.

  10. Factors Associated with Dental Caries in Primary Dentition in a Non-Fluoridated Rural Community of New South Wales, Australia

    Directory of Open Access Journals (Sweden)

    Amit Arora

    2017-11-01

    Full Text Available Dental caries persists as one of the most prevalent chronic diseases among children worldwide. This study aims to determine factors that influence dental caries in primary dentition among primary school children residing in the rural non-fluoridated community of Lithgow, New South Wales, Australia. A total of 495 children aged 5–10 years old from all the six primary schools in Lithgow were approached to participate in a cross-sectional survey prior to implementation of water fluoridation in 2014. Following parental consent, children were clinically examined for caries in their primary teeth, and parents were requested to complete a questionnaire on previous fluoride exposure, diet and relevant socio-demographic characteristics that influence oral health. Multiple logistic regression analysis was employed to examine the independent risk factors of primary dentition caries. Overall, 51 percent of children had dental caries in one or more teeth. In the multiple logistic regression analysis, child’s age (Adjusted Odd’s Ratio (AOR = 1.30, 95% CI: 1.14–1.49 and mother’s extraction history (AOR = 2.05, 95% CI: 1.40–3.00 were significantly associated with caries experience in the child’s primary teeth. In addition, each serve of chocolate consumption was associated with 52 percent higher odds (AOR = 1.52, 95% CI: 1.19–1.93 of primary dentition caries.

  11. Studies on Pu(IV)/(III)-oxalate precipitation from nitric acid containing high concentration of calcium and fluoride ions

    International Nuclear Information System (INIS)

    Kalsi, P.K.; Pawar, S.M.; Ghadse, D.R.; Joshi, A.R.; Ramakrishna, V.V.; Vaidya, V.N.; Venugopal, V.

    2003-01-01

    Plutonium (IV)/(III) oxalate precipitation from nitric acid solution, containing large amount of calcium and fluoride ions was investigated. It was observed that direct precipitation of Pu (IV) oxalate from nitric acid containing large amount of calcium and fluoride ions did not give good decontamination of Pu from calcium and fluoride impurities. However, incorporation of hydroxide precipitation using ammonium hydroxide prior to Pu (IV) oxalate precipitation results into PuO 2 with much less calcium and fluoride impurities. Whereas, good decontamination from calcium and fluoride impurities could be obtained by employing Pu (III) oxalate precipitation directly from nitric acid containing large amount of calcium and fluoride ions. A method was also developed to recover Pu from the oxalate waste containing calcium and fluoride ions. (author)

  12. 4-phenylbutyrate Mitigates Fluoride-Induced Cytotoxicity in ALC Cells

    OpenAIRE

    Suzuki, Maiko; Everett, Eric T.; Whitford, Gary M.; Bartlett, John D.

    2017-01-01

    Chronic fluoride over-exposure during pre-eruptive enamel development can cause dental fluorosis. Severe dental fluorosis is characterized by porous, soft enamel that is vulnerable to erosion and decay. The prevalence of dental fluorosis among the population in the USA, India and China is increasing. Other than avoiding excessive intake, treatments to prevent dental fluorosis remain unknown. We previously reported that high-dose fluoride induces endoplasmic reticulum (ER) stress and oxidative...

  13. Diagnosing dental caries in populations with different levels of dental fluorosis

    DEFF Research Database (Denmark)

    Nyvad, Bente; Machiulskiene, Vita; Fejerskov, Ole

    2009-01-01

    concentrations of 0.3 and 1.1 ppm (0.3 and 1.1 mg/l) fluoride, respectively, 150 children were clinically examined twice, 2 wk apart, for dental fluorosis, using the Thylstrup-Fejerskov index (TF index), and for dental caries using the Nyvad visual-tactile caries criteria. The prevalence of dental fluorosis......, a pronounced dental fluorosis background did not reduce the reliability of the caries recordings, which appeared to be slightly less reliable at very low levels of dental fluorosis.......The aim of this study was to assess the reliability of the Nyvad visual-tactile caries-diagnostic criteria when used among children who have been lifelong residents in areas with 'optimal' or low concentrations of fluoride in the drinking water. In each of two areas with drinking water fluoride...

  14. Efficacy of dental rinse formulations marketed in Abuja, Nigeria in ...

    African Journals Online (AJOL)

    This study assessed the microbial quality and effectiveness of seven brands of antiseptic dental rinses marketed in Abuja, Nigeria. Seven brands of dental rinses were randomly purchased from the open market and pharmacies. According to the products literature, the brands contained sodium fluoride + triclosan, sodium ...

  15. Investigation of metal fluoride thermal energy storage materials: availability, cost, and chemistry. Final report, July 15, 1976--December 15, 1976

    Energy Technology Data Exchange (ETDEWEB)

    Eichelberger, J.L.

    1976-12-01

    Storage of thermal energy in the 400 to 1000/sup 0/C range is attracting increasing consideration for use in solar power, central power, vehicular, and commercial process systems. This study investigates the practicality of using metal fluorides as the heat storage medium. The projected availability of metal fluorides has been studied and is shown to be adequate for widespread thermal storage use. Costs are projected and discussed in relation to thermal energy storage applications. Phase diagrams, heats of fusion, heat capacities, vapor pressures, toxicity, stability, volume changes, thermal conductivities, fusion kinetics, corrosion, and container materials of construction for a wide range of fluorides have been examined. Analyses of these data in consideration of thermal energy storage requirements have resulted in selection of the most cost-effective fluoride mixture for each of 23 temperature increments between 400 and 1000/sup 0/C. Thermo-physical properties of these 23 materials are presented. Comparison of fluoride with non-fluoride materials shows that the fluorides are suitable candidates for high temperature applications on the bases of cost, heat capacity/unit volume, heat capacity/unit weight, corrosive properties, and availability.

  16. Dental fluorosis in populations from Chiang Mai, Thailand with different fluoride exposures - paper 1: assessing fluorosis risk, predictors of fluorosis and the potential role of food preparation.

    Science.gov (United States)

    McGrady, Michael G; Ellwood, Roger P; Srisilapanan, Patcharawan; Korwanich, Narumanas; Worthington, Helen V; Pretty, Iain A

    2012-06-21

    To determine the severity of dental fluorosis in selected populations in Chiang Mai, Thailand with different exposures to fluoride and to explore possible risk indicators for dental fluorosis. Subjects were male and female lifetime residents aged 8-13 years. For each child the fluoride content of drinking and cooking water samples were assessed. Digital images were taken of the maxillary central incisors for later blind scoring for TF index (10% repeat scores). Interview data explored previous cooking and drinking water use, exposure to fluoride, infant feeding patterns and oral hygiene practices. Data from 560 subjects were available for analysis (298 M, 262 F). A weighted kappa of 0.80 was obtained for repeat photographic scores. The prevalence of fluorosis (TF 3+) for subjects consuming drinking and cooking water with a fluoride concentration of cooking water >0.9 ppm F the prevalence of fluorosis (TF 3+) rose to 37.3%. Drinking and cooking water at age 3, water used for infant formula and water used for preparing infant food all demonstrated an increase in fluorosis severity with increase in water fluoride level (p cooking water (≥1.6 ppm). The consumption of drinking water with fluoride content >0.9 ppm and use of cooking water with fluoride content >1.6 ppm were associated with an increased risk of aesthetically significant dental fluorosis. Fluoride levels in the current drinking and cooking water sources were strongly correlated with fluorosis severity. Further work is needed to explore fluorosis risk in relation to total fluoride intake from all sources including food preparation.

  17. Antibacterial activity against Streptococcus mutans and inhibition of bacterial induced enamel demineralization of propolis, miswak, and chitosan nanoparticles based dental varnishes.

    Science.gov (United States)

    Wassel, Mariem O; Khattab, Mona A

    2017-07-01

    Using natural products can be a cost-effective approach for caries prevention especially in low income countries where dental caries is highly prevalent and the resources are limited. Specially prepared dental varnishes containing propolis, miswak, and chitosan nanoparticles (CS-NPs) with or without sodium fluoride (NaF) were assessed for antibacterial effect against Streptococcus mutans ( S. mutans ) using disk diffusion test. In addition, the protective effect of a single pretreatment of primary teeth enamel specimens against in vitro bacterial induced enamel demineralization was assessed for 3 days. All natural products containing varnishes inhibited bacterial growth significantly better than 5% NaF varnish, with NaF loaded CS-NPs (CSF-NPs) showing the highest antibacterial effect, though it didn't significantly differ than those of other varnishes except miswak ethanolic extract (M) varnish. Greater inhibitory effect was noted with varnish containing freeze dried aqueous miswak extract compared to that containing ethanolic miswak extract, possibly due to concentration of antimicrobial substances by freeze drying. Adding natural products to NaF in a dental varnish showed an additive effect especially compared to fluoride containing varnish. 5% NaF varnish showed the best inhibition of demineralization effect. Fluoride containing miswak varnish (MF) and CSF-NPs varnish inhibited demineralization significantly better than all experimental varnishes, especially during the first 2 days, though CSF-NPs varnish had a low fluoride concentration, probably due to better availability of fluoride ions and the smaller size of nanoparticles. Incorporating natural products with fluoride into dental varnishes can be an effective approach for caries prevention, especially miswak and propolis when financial resources are limited.

  18. Health promotion and dental caries.

    Science.gov (United States)

    Maltz, Marisa; Jardim, Juliana Jobim; Alves, Luana Severo

    2010-01-01

    The central idea of the Brazilian health system is to prevent the establishment of disease or detect it as early as possible. Prevention and treatment of dental caries are related to behavioral factors, including dietary and oral hygiene habits, which are related to many chronic diseases. Dental health promotion therefore should be fully integrated into broadly based health-promoting strategies and actions such as food and health policies, and general hygiene (including oral hygiene), among others. For decades, a linear relationship between sugar consumption and caries has been observed. Recent data has indicated that this relationship is not as strong as it used to be before the widespread use of fluoride. However, diet is still a key factor acting in the carious process. Oral hygiene is a major aspect when it comes to caries, since dental biofilm is its etiological factor. Oral hygiene procedures are effective in controlling dental caries, especially if plaque removal is performed adequately and associated with fluoride. An alternative to a more efficient biofilm control in occlusal areas is the use of dental sealants, which are only indicated for caries-active individuals. If a cavity is formed as a consequence of the metabolic activity of the biofilm, a restorative material or a sealant can be placed to block access of the biofilm to the oral environment in order to prevent caries progress. The prevention of dental caries based on common risk-factor strategies (diet and hygiene) should be supplemented by more disease-specific policies such as rational use of fluoride, and evidence-based dental health care.

  19. Health promotion and dental caries

    Directory of Open Access Journals (Sweden)

    Marisa Maltz

    2010-01-01

    Full Text Available The central idea of the Brazilian health system is to prevent the establishment of disease or detect it as early as possible. Prevention and treatment of dental caries are related to behavioral factors, including dietary and oral hygiene habits, which are related to many chronic diseases. Dental health promotion therefore should be fully integrated into broadly based health-promoting strategies and actions such as food and health policies, and general hygiene (including oral hygiene, among others. For decades, a linear relationship between sugar consumption and caries has been observed. Recent data has indicated that this relationship is not as strong as it used to be before the widespread use of fluoride. However, diet is still a key factor acting in the carious process. Oral hygiene is a major aspect when it comes to caries, since dental biofilm is its etiological factor. Oral hygiene procedures are effective in controlling dental caries, especially if plaque removal is performed adequately and associated with fluoride. An alternative to a more efficient biofilm control in occlusal areas is the use of dental sealants, which are only indicated for caries-active individuals. If a cavity is formed as a consequence of the metabolic activity of the biofilm, a restorative material or a sealant can be placed to block access of the biofilm to the oral environment in order to prevent caries progress. The prevention of dental caries based on common risk-factor strategies (diet and hygiene should be supplemented by more disease-specific policies such as rational use of fluoride, and evidence-based dental health care.

  20. Risk assessment of fluoride exposure in drinking water of Tunisia.

    Science.gov (United States)

    Guissouma, Wiem; Hakami, Othman; Al-Rajab, Abdul Jabbar; Tarhouni, Jamila

    2017-06-01

    The presence of fluoride in drinking water is known to reduce dental cavities among consumers, but an excessive intake of this anion might leads to dental and skeletal fluorosis. This study reports a complete survey of the fluoridated tap water taken from 100 water consumption points in Tunisia. The fluoride concentrations in tap water were between 0 and 2.4 mg L -1 . Risk assessment of Fluoride exposure was assessed depending on the age of consumers using a four-step method: hazard identification, toxicity reference values selection (TRVs), daily exposure assessment, and risk characterization. Our findings suggest that approximately 75% of the Tunisian population is at risk for dental decay, 25% have a potential dental fluorosis risk, and 20% might have a skeletal fluorosis risk according to the limits of fluoride in drinking water recommended by WHO. More investigations are recommended to assess the exposure risk of fluoride in other sources of drinking water such as bottled water. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Influence of noble metals alloying additions on the corrosion behaviour of titanium in a fluoride-containing environment.

    Science.gov (United States)

    Rosalbino, F; Delsante, S; Borzone, G; Scavino, G

    2012-05-01

    Titanium alloys exhibit excellent corrosion resistance in most aqueous media due to the formation of a stable oxide film, and some of these alloys (particularly Ti-6Al-7Nb) have been chosen for surgical and odontological implants for their resistance and biocompatibility. Treatment with fluorides (F(-)) is known to be the main method for preventing plaque formation and dental caries. Toothpastes, mouthwashes, and prophylactic gels can contain from 200 to 20,000 ppm F(-) and can affect the corrosion behaviour of titanium alloy devices present in the oral cavity. In this work, the electrochemical corrosion behaviour of Ti-1M alloys (M = Ag, Au, Pd, Pt) was assessed in artificial saliva of pH = 3.0 containing 910 ppm F(-) (0.05 M NaF) through open circuit potential, E(OC), and electrochemical impedance spectroscopy (EIS) measurements. The corrosion behaviour of the Ti-6Al-7Nb commercial alloy was also evaluated for comparison. E (OC) measurements show an active behaviour for all the titanium alloys in fluoridated acidified saliva due to the presence of significant concentrations of HF and HF(2) (-) species that dissolve the spontaneous air-formed oxide film giving rise to surface activation. However, an increase in stability of the passive oxide layer and consequently a decrease in surface activation is observed for the Ti-1M alloys. This behaviour is confirmed by EIS measurements. In fact, the Ti-6Al-7Nb alloy exhibits lower impedance values as compared with Ti-1M alloys, the highest values being measured for the Ti-1Au alloy. The experimental results show that the corrosion resistance of the studied Ti-1M alloys is similar to or better than that of Ti-6Al-7Nb alloy currently used as biomaterial, suggesting their potential for dental applications.

  2. Application of Titanium Compounds to Reduce Fluoride Ion in Water Resources with High Fluoride Ion Contents

    Directory of Open Access Journals (Sweden)

    Fariborz Riahi

    2005-06-01

    Full Text Available The present work describes studies on the sorption of fluoride ions from water by titanium compounds used in water treatment to reduce fluoride content in water resources. There are different methods of reducing fluoride ion in water, each associated with specific problems such as secondary contamination, environmental contamination, high costs, or the need for primary and secondary treatment. In this study, application of titanium sulfate and Metatitanic acid produced from titanium ore concentrate (ileminite is investigated in the removal of fluoride ion and the possibility of complete purification of fluorine containing wastewater is examined to determine the optimal conditions. Metatitanic acid has a great sorption property for fluoride ion. Also titanium sulfate is a suitable and more effective material for this purpose. Efficiency of this material in reducing fluoride ion content is 99.9% and it is possible to refresh sorbet material for reuse without problems arising from Ti+4 ion contamination.

  3. Fifty years of Brazilian Dental Materials Group: scientific contributions of dental materials field evaluated by systematic review

    Science.gov (United States)

    ROSA, Wellington Luiz de Oliveira; SILVA, Tiago Machado; LIMA, Giana da Silveira; SILVA, Adriana Fernandes; PIVA, Evandro

    2016-01-01

    ABSTRACT Objective A systematic review was conducted to analyze Brazilian scientific and technological production related to the dental materials field over the past 50 years. Material and Methods This study followed the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (Prisma) statement. Searches were performed until December 2014 in six databases: MedLine (PubMed), Scopus, LILACS, IBECS, BBO, and the Cochrane Library. Additionally, the Brazilian patent database (INPI - Instituto Nacional de Propriedade Industrial) was screened in order to get an overview of Brazilian technological development in the dental materials field. Two reviewers independently analyzed the documents. Only studies and patents related to dental materials were included in this review. Data regarding the material category, dental specialty, number of documents and patents, filiation countries, and the number of citations were tabulated and analyzed in Microsoft Office Excel (Microsoft Corporation, Redmond, Washington, United States). Results A total of 115,806 studies and 53 patents were related to dental materials and were included in this review. Brazil had 8% affiliation in studies related to dental materials, and the majority of the papers published were related to dental implants (1,137 papers), synthetic resins (681 papers), dental cements (440 papers), dental alloys (392 papers) and dental adhesives (361 papers). The Brazilian technological development with patented dental materials was smaller than the scientific production. The most patented type of material was dental alloys (11 patents), followed by dental implants (8 patents) and composite resins (7 patents). Conclusions Dental materials science has had a substantial number of records, demonstrating an important presence in scientific and technological development of dentistry. In addition, it is important to approximate the relationship between academia and industry to expand the technological development in

  4. Caries With Dental Fluorosis and Oral Health Behaviour Among 12-year School Children In Moderate-fluoride Drinking Water Community in Quetta, Pakistan

    International Nuclear Information System (INIS)

    Sami, E.; Vichayanrat, T.; Satitvipawee, P.

    2016-01-01

    Objective: To determine the prevalence of dental caries and its relationship with dental fluorosis, oral health behaviour and dietary behaviour among 12-year school children in moderate-fluoride drinking water community in Quetta, Pakistan. Study Design: Cross-sectional study. Place and Duration of Study: Government and private schools of Quetta, from November 2012 to February 2013. Methodology: A total of 349 children aged 12-year from 14 randomly selected schools were included. The data collection was done on questionnaire designed for children. Dental caries status was examined by using WHO criteria. Result: Dental caries was found in 81 children (23.2 percent) with mean DMFT 0.61. Boys had 1.6 times more chance to have dental caries than girls. Dental fluorosis was found in 63.6 percent of children with majority of moderate degree (50.5 percent). Dental fluorosis status was found significantly associated with dental caries status in children. The children who had mild, moderate and severe fluorosis, had 4 times more chances to develop caries than those who did not have fluorosis. There was no significant association between children's caries status and use of paste, brushing habit, miswak, and visit to the dentist. The use of pastries and juices had a direct relation with the children's dental caries status. Conclusion: Dental caries in children of Quetta is not so much frequent as compared to the fluoride deficient countries. However, the high prevalence of moderate dental fluorosis and consumption of pastries and juices resulted in dental caries. (author)

  5. A review of slow-release fluoride devices.

    Science.gov (United States)

    Toumba, K J; Al-Ibrahim, N S; Curzon, M E J

    2009-09-01

    Fluoride has been used to combat dental caries using a number of different clinical approaches. An exciting relatively new development is fluoride slow-releasing devices that consistently elevate intra-oral fluoride levels of plaque and saliva for prolonged periods of up to two years. The literature on the use of slow-releasing fluoride devices in dentistry were reviewed. A Medline search on key words was carried out. All papers in English were individually reviewed. Slow-releasing fluoride devices have been shown to be effective in elevating salivary fluoride levels in both animals and human studies and to enhance the remineralisation of dental enamel. They have been demonstrated to be safe to use and without the risk of fluoride toxicity. A double blind randomised clinical trial demonstrated 76% fewer new carious surface increment in high caries-risk children after two years. These devices have a number of potential uses in dentistry and in particular have great potential for caries prevention of non-compliant high caries-risk groups.

  6. Role of dental restoration materials in oral mucosal lichenoid lesions

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    Rajneesh Sharma

    2015-01-01

    Full Text Available Background: Dental restorative materials containing silver-mercury compounds have been known to induce oral lichenoid lesions. Objectives: To determine the frequency of contact allergy to dental restoration materials in patients with oral lichenoid lesions and to study the effect of removal of the materials on the lesions. Results: Forty-five patients were recruited in three groups of 15 each: Group A (lesions in close contact with dental materials, Group B (lesions extending 1 cm beyond the area of contact and Group C (no topographic relationship. Thirty controls were recruited in two groups of 15 individuals each: Group D (oral lichenoid lesions but no dental material and Group E (dental material but no oral lichenoid lesions. Patch tests were positive in 20 (44.5% patients. Mercury was the most common allergen to elicit a positive reaction in eight patients, followed by nickel (7, palladium (5, potassium dichromate (3, balsam of Peru, gold sodium thiosulphate 2 and tinuvin (2 and eugenol (1, cobalt chloride (1 and carvone (1. Seven patients elicited positive response to more than one allergen. In 13 of 20 patients who consented to removal of the dental material, complete healing was observed in 6 (30%, marked improvement in 7 (35% and no improvement in 7 (35% patients. Relief of symptoms was usually observed 3 months after removal. Limitations: Limited number of study subjects and short follow up after removal/replacement of dental restoration materials are the main limitations of this study. Conclusion: Contact allergy to amalgam is an important etiologic factor in oral lichenoid lesions and removal of restorative material should be offered to patients who have lesions in close proximity to the dental material.

  7. Protective effect of lycopene on fluoride-induced ameloblasts apoptosis and dental fluorosis through oxidative stress-mediated Caspase pathways.

    Science.gov (United States)

    Li, Weishan; Jiang, Binghua; Cao, Xianglin; Xie, Yongjiang; Huang, Ting

    2017-01-05

    Fluoride is an environmental toxicant and induces dental fluorosis and oxidative stress. Lycopene (LYC) is an effective antioxidant that is reported to attenuate fluoride toxicity. To determine the effects of LYC on sodium fluoride (NaF) -induced teeth and ameloblasts toxicity, rats were treated with NaF (10 mg/kg) and/or LYC (10 mg/kg) by orally administration for 5 weeks; ameloblasts were treated with NaF (5 mM) and/or LYC (2 μM) for 6 h. We found that the concentrations of fluoride, malondialdehyde (MDA) and reactive oxygen species (ROS), gene expressions and activities of Caspase-9 and Caspase-3, and the gene expressions of Bax were significantly decreased, while the activities of superoxide dismutase (SOD) and glutathione peroxidase (GPX), the gene expression of Bcl-2 were significantly increased in the LYC + NaF-treated rats group; concentrations of MDA and ROS, gene expressions and activities of Caspase-9 and Caspase-3, and the gene expression of Bax, and ameloblasts apoptosis rate were significantly decreased, while the activities of SOD and GPX, the gene expression of Bcl-2 were significantly increased in the LYC + NaF-treated ameloblasts group. These results suggest that LYC significantly combated NaF-induced ameloblasts apoptosis and dental fluorosis by attenuation oxidative stress and down-regulation Caspase pathway. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  8. The implications of the new paradigm of dental caries.

    Science.gov (United States)

    Kidd, Edwina

    2011-12-01

    The caries process is the ubiquitous, natural metabolism in the biofilm that causes numerous fluctuations in pH. The interaction of this biofilm with the dental tissues may result in a caries lesion. However, lesion formation and progression can be controlled, particularly by disturbing plaque regularly with a fluoride containing toothpaste. This paradigm implies that everyone with teeth is at risk to lesion development. Treatment of caries is principally non-operative, involving plaque control, fluoride and a sensible diet. Operative dentistry repairs un-cleansable cavities and is part of plaque control. A diagnosis is a mental resting place on the way to a treatment decision. The relevant diagnostic features with respect to caries are lesion activity (active lesions require active management) and un-cleansable cavities. When teaching undergraduates, it is important that they are credited for the non-operative treatment of caries as well as for operative dentistry. This is equally important in dental practice where an appropriate skills mix of the dental team is required to deliver dental health cost-effectively. Training more dentists may be an expensive mistake as far as disease control is concerned. It is ironic that dentists make most money from operative care and specialist treatment when disease control could be delivered relatively cheaply. The key to dental health is regular and effective plaque control with a fluoride containing toothpaste, from cradle to grave. Copyright © 2011 Elsevier Ltd. All rights reserved.

  9. Fifty years of Brazilian Dental Materials Group: scientific contributions of dental materials field evaluated by systematic review.

    Science.gov (United States)

    Rosa, Wellington Luiz de Oliveira; Silva, Tiago Machado; Lima, Giana da Silveira; Silva, Adriana Fernandes; Piva, Evandro

    2016-01-01

    A systematic review was conducted to analyze Brazilian scientific and technological production related to the dental materials field over the past 50 years. This study followed the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (Prisma) statement. Searches were performed until December 2014 in six databases: MedLine (PubMed), Scopus, LILACS, IBECS, BBO, and the Cochrane Library. Additionally, the Brazilian patent database (INPI - Instituto Nacional de Propriedade Industrial) was screened in order to get an overview of Brazilian technological development in the dental materials field. Two reviewers independently analyzed the documents. Only studies and patents related to dental materials were included in this review. Data regarding the material category, dental specialty, number of documents and patents, filiation countries, and the number of citations were tabulated and analyzed in Microsoft Office Excel (Microsoft Corporation, Redmond, Washington, United States). A total of 115,806 studies and 53 patents were related to dental materials and were included in this review. Brazil had 8% affiliation in studies related to dental materials, and the majority of the papers published were related to dental implants (1,137 papers), synthetic resins (681 papers), dental cements (440 papers), dental alloys (392 papers) and dental adhesives (361 papers). The Brazilian technological development with patented dental materials was smaller than the scientific production. The most patented type of material was dental alloys (11 patents), followed by dental implants (8 patents) and composite resins (7 patents). Dental materials science has had a substantial number of records, demonstrating an important presence in scientific and technological development of dentistry. In addition, it is important to approximate the relationship between academia and industry to expand the technological development in countries such as Brazil.

  10. Dental Fluorosis and Dental Caries Prevalence among 12 and 15-Year-Old School Children in Nalgonda District, Andhra Pradesh, India

    Science.gov (United States)

    Sukhabogi, JR; Parthasarathi, P; Anjum, S; Shekar, BRC; Padma, CM; Rani, AS

    2014-01-01

    Background: Fluoride is a double edged sword. The assessment of dental caries and fluorosis in endemic fluoride areas will facilitate in assessing the relation between fluoride concentrations in water with dental caries, dental fluorosis simultaneously. Aim: The objective of the following study is to assess the dental caries and dental fluorosis prevalence among 12 and 15-year-old school children in Nalgonda district, Andhra Pradesh, India. Subjects and Methods: This was a cross-sectional study. Two stage cluster sampling technique was employed to select 20 schools from Nalgonda district. The oral examination of available 12 and 15-year-old children fulfilling the inclusion and exclusion criteria was carried out to assess dental caries and fluorosis. The examination was conducted by a single trained and calibrated examiner using the mouth mirror and community periodontal index probe under natural daylight. These areas were divided into four categories, low, medium, high and very high fluoride areas based on the fluoride concentration at the time of statistical analysis. The data was analyzed using Statistical Package for the Social Sciences version 16 (IBM, Chicago, USA). Results: The caries prevalence was less among 12-year-old children (39.9% [369/924]) compared with 15-years-old children (46.7% [444/951]). The prevalence was more among females (50.4% [492/977]) than males (35.8% [321/898]). The prevalence was more in low fluoride area (60.5% [300/496]) followed by very high fluoride area (54.8% [201/367]), high fluoride area (32.4% [293/904]) and medium fluoride area (17.6% [19/108]) in the descending order. The fluorosis prevalence increased with increasing fluoride concentration with no difference in gender and age distribution. Conclusion: Low fluoride areas require fluoridation or alternate sources of fluoride, whereas high fluoride areas require defluoridation. Defluoridation of water is an immediate requirement in areas with fluoride concentration of 4

  11. Dental fluorosis in populations from Chiang Mai, Thailand with different fluoride exposures – Paper 1: assessing fluorosis risk, predictors of fluorosis and the potential role of food preparation

    Science.gov (United States)

    2012-01-01

    Background To determine the severity of dental fluorosis in selected populations in Chiang Mai, Thailand with different exposures to fluoride and to explore possible risk indicators for dental fluorosis. Methods Subjects were male and female lifetime residents aged 8–13 years. For each child the fluoride content of drinking and cooking water samples were assessed. Digital images were taken of the maxillary central incisors for later blind scoring for TF index (10% repeat scores). Interview data explored previous cooking and drinking water use, exposure to fluoride, infant feeding patterns and oral hygiene practices. Results Data from 560 subjects were available for analysis (298 M, 262 F). A weighted kappa of 0.80 was obtained for repeat photographic scores. The prevalence of fluorosis (TF 3+) for subjects consuming drinking and cooking water with a fluoride concentration of 0.9 ppm F the prevalence of fluorosis (TF 3+) rose to 37.3%. Drinking and cooking water at age 3, water used for infant formula and water used for preparing infant food all demonstrated an increase in fluorosis severity with increase in water fluoride level (p 0.9 ppm and use of cooking water with fluoride content >1.6 ppm were associated with an increased risk of aesthetically significant dental fluorosis. Fluoride levels in the current drinking and cooking water sources were strongly correlated with fluorosis severity. Further work is needed to explore fluorosis risk in relation to total fluoride intake from all sources including food preparation. PMID:22720834

  12. Comparative Evaluation of Fluoride Releasing Ability of Various Restorative Materials after the Application of Surface Coating Agents – An In-vitro Study

    Science.gov (United States)

    Kishore, GVS; Sai-Sankar, AJ; Sridhar, M; Pranitha, Kakarla; Sai-Krishna, VS

    2016-01-01

    Introduction Fluoride plays a key role in prevention of dental caries and is also an essential element for oral health promotion both in children and adults. Aim The aim of the present study was to evaluate the effect of surface coating (petroleum jelly, G-Coat Plus) on the fluoride releasing property of conventional Glass Ionomer Cement (GIC) and Zirconomer. Materials and Methods A total of 30 disk shaped brass mold specimens (6±0.1mm in diameter and 2±0.1mm thickness) for each test group were fabricated with conventional GIC (Group A) and Zirconomer (Group B). These test groups were further divided into three subgroups of 10 each. The unprotected specimens act as control (Group A1 and B1), G-Coat Plus specimens as (Group A2 and B2) and for the remaining specimens petroleum jelly was applied (Group A3 and B3). Fluoride ion concentration was measured with a combination of fluoride ion specific electrode and ion analyzer for every 24 hours for 15 days. The data was statistically analyzed using Kruskal Wallis and Mann-Whitney U test. Results The Group B released significantly more fluoride than Group A. Among all the subgroups the greatest amount of fluoride was released from Group B1, in the first 24 hours followed by A1 and B2. The least was observed on 15th day with Group B3 and A3. Conclusion Both the tested materials (GIC and Zirconomer) used in the study exhibited fluoride release whether protected or unprotected with surface coating. Though there was a difference between the groups, the pattern of fluoride release was similar and continuous throughout the study period i.e., first the initial burst followed by sustained release. The results revealed Zirconomer released more fluoride and is comparable to conventional GIC. PMID:28209001

  13. Dental fluorosis in populations from Chiang Mai, Thailand with different fluoride exposures – Paper 1: assessing fluorosis risk, predictors of fluorosis and the potential role of food preparation

    Directory of Open Access Journals (Sweden)

    McGrady Michael G

    2012-06-01

    Full Text Available Abstract Background To determine the severity of dental fluorosis in selected populations in Chiang Mai, Thailand with different exposures to fluoride and to explore possible risk indicators for dental fluorosis. Methods Subjects were male and female lifetime residents aged 8–13 years. For each child the fluoride content of drinking and cooking water samples were assessed. Digital images were taken of the maxillary central incisors for later blind scoring for TF index (10% repeat scores. Interview data explored previous cooking and drinking water use, exposure to fluoride, infant feeding patterns and oral hygiene practices. Results Data from 560 subjects were available for analysis (298 M, 262 F. A weighted kappa of 0.80 was obtained for repeat photographic scores. The prevalence of fluorosis (TF 3+ for subjects consuming drinking and cooking water with a fluoride concentration of 0.9 ppm F the prevalence of fluorosis (TF 3+ rose to 37.3%. Drinking and cooking water at age 3, water used for infant formula and water used for preparing infant food all demonstrated an increase in fluorosis severity with increase in water fluoride level (p  Conclusions The consumption of drinking water with fluoride content >0.9 ppm and use of cooking water with fluoride content >1.6 ppm were associated with an increased risk of aesthetically significant dental fluorosis. Fluoride levels in the current drinking and cooking water sources were strongly correlated with fluorosis severity. Further work is needed to explore fluorosis risk in relation to total fluoride intake from all sources including food preparation.

  14. Quantitative study of fluoride transport during subsurface dissolution of dental enamel

    International Nuclear Information System (INIS)

    Chu, J.S.; Fox, J.L.; Higuchi, W.I.

    1989-01-01

    Previous studies using bovine dental enamel as a model have shown that surface and subsurface dissolution of enamel may be governed by micro-environmental solution conditions. We have now investigated the demineralization phenomenon more rigorously with the primary objective of developing a method for deducing solution species concentration profiles as a function of time from appropriate experimental data. More specifically, in this report, a model-independent method is described for determination of the pore solution fluoride gradients in bovine enamel during subsurface demineralization. Microradiography was used to determine the mineral density profiles, and an electron microprobe technique to determine total fluoride (F) profiles associated with the enamel. In each case, matched sections of bovine enamel were exposed to partially saturated acetate buffers at pH = 4.5 containing 0.5 ppm F for various periods of time (from six to 24 hours). The treated enamel was found to have an intact surface layer and subsurface demineralization. The extent of the demineralization and the depths of the lesions increased with time in all cases. The data were first used to calculate (a) the total F gradients in the enamel at various times, and (b) the local uptake rate of F as a function of time and position. Then, by manipulation of the equations describing the uptake and transport of F, we calculated the pore diffusion rate of F and the micro-environmental solution F concentration in the aqueous pores as a function of time and of distance from the enamel surface. It was also possible to calculate an intrinsic F diffusion coefficient in the pores, which was about 1.0 X 10(-5) cm2/sec, in good agreement with reported values

  15. Biomonitoring Equivalents for interpretation of urinary fluoride.

    Science.gov (United States)

    Aylward, L L; Hays, S M; Vezina, A; Deveau, M; St-Amand, A; Nong, A

    2015-06-01

    Exposure to fluoride is widespread due to its natural occurrence in the environment and addition to drinking water and dental products for the prevention of dental caries. The potential health risks of excess fluoride exposure include aesthetically unacceptable dental fluorosis (tooth mottling) and increased skeletal fragility. Numerous organizations have conducted risk assessments and set guidance values to represent maximum recommended exposure levels as well as recommended adequate intake levels based on potential public health benefits of fluoride exposure. Biomonitoring Equivalents (BEs) are estimates of the average biomarker concentrations corresponding to such exposure guidance values. The literature on daily urinary fluoride excretion rates as a function of daily fluoride exposure was reviewed and BE values corresponding to the available US and Canadian exposure guidance values were derived for fluoride in urine. The derived BE values range from 1.1 to 2.1mg/L (1.2-2.5μg/g creatinine). Concentrations of fluoride in single urinary spot samples from individuals, even under exposure conditions consistent with the exposure guidance values, may vary from the predicted average concentrations by several-fold due to within- and across-individual variation in urinary flow and creatinine excretion rates and due to the rapid elimination kinetics of fluoride. Thus, the BE values are most appropriately applied to screen population central tendency estimates for biomarker concentrations rather than interpretation of individual spot sample concentrations. Copyright © 2015. Published by Elsevier Inc.

  16. An In-Vitro Study on the Release of Fluoride from Two Restorative Materials and Their Rechargeability after Exposure to Daily 1000 ppm Fluoride

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    A. Kowsari

    2005-09-01

    Full Text Available Statement of Problem: Since the fluoride releases from materials with the property of releasing fluoride are decreasing gradually, it seems that probably the material rechargeability is more important than their long-term fluoride release.Purpose: the objective of this study was to asses the fluoride release and rechargeability of 2 types of fluoride releasing restorative materials, a resin modified glass ionomer(Vitremer and a compomer (Compoglass F, after exposure to daily NaF solutionscontaining 1000 ppm F, for 1 minute.Materials and Methods: Twelve discs ( 8 mm ×2 mm of each of the materials were fabricated, and divided into 2 groups (test and control. All discs were stored in 4 mL artificial saliva at 37°C. In group 1 (N=6, the specimens were immersed in artificialsaliva which was changed daily for 25 days. In group 2 (N=6, in addition to receiving the same treatment as group 1, the specimens were immersed in NaF solution (1000ppm F, ph=6.9 for 1 minute before daily saliva change. A potentiometer was used to determine the amount of fluoride released on days 1, 2, 3, 5, 10, 15, 20 and 25, after the daily saliva change, in all study groups. Data were analyzed by the t-student test after confirmation of the equality of variances by Leven’s test.Results: Both materials continued releasing fluoride throughout the whole study period. For each material, the release was highest on day one. During the first 3 days,glass ionomer released significantly higher amounts of fluoride as compared to compomer (p0.05. After exposure to NaF solution, none of the materials showed statistically significant rechargeability (p>0.05 and the amount of fluoride-releasecontinued to drop during the study period in similar patterns for both the test and the control groups.Conclusion: It may be concluded that rechargeability of glass ionomer and compomer,using daily neutral fluoride mouth rinses and toothpastes does not occur in reliable amounts.

  17. Industrial fluoride pollution: chronic fluoride poisoning in Cornwall Island cattle

    Energy Technology Data Exchange (ETDEWEB)

    Krook, L.; Maylin, G.A.

    1979-04-01

    An aluminum plant on the south bank of the St. Lawrence River, southwest of Cornwall Island, Ontario, Canada, has emitted 0.816 metric tons of fluoride daily since 1973. Considerably higher amounts were emitted from 1959 to 1973. The plant was designated as the major source of fluoride emissions impacting on Cornwall Island. Cattle located on this island showed signs of chronic fluoride poisoning. This poisoning was manifested clinically by stunted growth and dental fluorosis to a degree of severe interference with drinking and mastication. This Cornwall Island herds study indicates that the established tolerance level of fluoride for performance of dairy and beef cattle is not valid since the tolerance level was set based on experiments with healthy calves which were exposed to dietary fluoride from 3 to 4 months of age and not on cattle which were chronically exposed to fluoride from conception to death. 56 references.

  18. Mechanisms of inhibition by fluoride of urease activities of cell suspensions and biofilms of Staphylococcus epidermidis, Streptococcus salivarius, Actinomyces naeslundii and of dental plaque.

    Science.gov (United States)

    Barboza-Silva, E; Castro, A C D; Marquis, R E

    2005-12-01

    Fluoride is known to be a potent inhibitor of bacterial ureases and can also act in the form of hydrofluoric acid as a transmembrane proton conductor to acidify the cytoplasm of intact cells with possible indirect, acid inhibition of urease. Our research objectives were to assess the inhibitory potencies of fluoride for three urease-positive bacteria commonly found in the mouth and to determine the relative importance of direct and indirect inhibition of ureases for overall inhibition of intact cells or biofilms. The experimental design involved intact bacteria in suspensions, mono-organism biofilms, cell extracts, and dental plaque. Standard enzymatic assays for ammonia production from urea were used. We found that ureolysis by cells in suspensions or mono-organism biofilms of Staphylococcus epidermidis, Streptococcus salivarius or Actinomyces naeslundii was inhibited by fluoride at plaque levels of 0.1-0.5 mm in a pH-dependent manner. The results of experiments with the organic weak acids indomethacin and capric acid, which do not directly inhibit urease enzyme, indicated that weak-acid effects leading to cytoplasmic acidification are also involved in fluoride inhibition. However, direct fluoride inhibition of urease appeared to be the major mechanism for reduction in ureolytic activity in acid environments. Results of experiments with freshly harvested supragingival dental plaque indicated responses to fluoride similar to those of S. salivarius with pH-dependent fluoride inhibition and both direct and indirect inhibition of urease. Fluoride can act to diminish alkali production from urea by oral bacteria through direct and indirect mechanisms.

  19. Determination of fluoride source in ground water using petrographic studies in Dashtestan area, south of Iran

    Science.gov (United States)

    Battaleb-Looie, Sedigheh; Moore, Farid, ,, Dr.

    2010-05-01

    The groundwater occurs in Dashtestan area, contains a high level of fluoride. Since groundwater is vastly used for drinking and irrigation purposes, the local residents are at high risk of fluoride toxicity, as already evidenced by the occurrence of dental Fluorosis in many residents. 35 surface and groundwater samples were collected in September, 2009. The results show that in 23 samples the fluoride concentration is above the permissible level (1.5ppm). Petrographic study of lithological units in the catchment area indicates that mica minerals are the most probable source of fluoride content in the study area.

  20. FLUORIDE: A REVIEW OF USE AND EFFECTS ON HEALTH.

    Science.gov (United States)

    Kanduti, Domen; Sterbenk, Petra; Artnik, Barbara

    2016-04-01

    Appropriate oral health care is fundamental for any individual's health. Dental caries is still one of the major public health problems. The most effective way of caries prevention is the use of fluoride. The aim of our research was to review the literature about fluoride toxicity and to inform physicians, dentists and public health specialists whether fluoride use is expedient and safe. Data we used in our review were systematically searched and collected from web pages and documents published from different international institutions. Fluoride occurs naturally in our environment but we consume it in small amounts. Exposure can occur through dietary intake, respiration and fluoride supplements. The most important factor for fluoride presence in alimentation is fluoridated water. Methods, which led to greater fluoride exposure and lowered caries prevalence, are considered to be one of the greatest accomplishments in the 20th century`s public dental health. During pregnancy, the placenta acts as a barrier. The fluoride, therefore, crosses the placenta in low concentrations. Fluoride can be transmitted through the plasma into the mother's milk; however, the concentration is low. The most important action of fluoride is topical, when it is present in the saliva in the appropriate concentration. The most important effect of fluoride on caries incidence is through its role in the process of remineralization and demineralization of tooth enamel. Acute toxicity can occur after ingesting one or more doses of fluoride over a short time period which then leads to poisoning. Today, poisoning is mainly due to unsupervised ingestion of products for dental and oral hygiene and over-fluoridated water. Even though fluoride can be toxic in extremely high concentrations, it`s topical use is safe. The European Academy of Paediatric Dentistry (EAPD) recommends a preventive topical use of fluoride supplements because of their cariostatic effect.

  1. Acid demineralization susceptibility of dental enamel submitted to different bleaching techniques and fluoridation regimens.

    Science.gov (United States)

    Salomão, Dlf; Santos, Dm; Nogueira, Rd; Palma-Dibb, Rg; Geraldo-Martins, Vr

    2014-01-01

    The aim of the current study was to assess the acid demineralization susceptibility of bleached dental enamel submitted to different fluoride regimens. One hundred bovine enamel blocks (6×6×3 mm) were randomly divided into 10 groups (n=10). Groups 1 and 2 received no bleaching. Groups 3 to 6 were submitted to an at-home bleaching technique using 6% hydrogen peroxide (HP; G3 and G4) or 10% carbamide peroxide (CP; G5 and G6). Groups 7 to 10 were submitted to an in-office bleaching technique using 35% HP (G7 and G8) or 35% CP (G9 and G10). During bleaching, a daily fluoridation regimen of 0.05% sodium fluoride (NaF) solution was performed on groups 3, 5, 7, and 9, while weekly fluoridation with a 2% NaF gel was performed on groups 4, 6, 8, and 10. The samples in groups 2 to 10 were pH cycled for 14 consecutive days. The samples from all groups were then assessed by cross-sectional Knoop microhardness at different depths from the outer enamel surface. The average Knoop hardness numbers (KHNs) were compared using one-way analysis of variance and Tukey tests (α=0.05). The comparison between groups 1 and 2 showed that the demineralization method was effective. The comparison among groups 2 to 6 showed the same susceptibility to acid demineralization, regardless of the fluoridation method used. However, the samples from groups 8 and 10 showed more susceptibility to acid demineralization when compared with group 2 (penamel to acid demineralization. However, the use of 35% HP and 35% CP must be associated with a daily fluoridation regimen, otherwise the in-office bleaching makes the bleached enamel more susceptible to acid demineralization.

  2. Fluoride Consumption and Its Impact on Oral Health

    Directory of Open Access Journals (Sweden)

    Luis Fernando Jacinto-Alemán

    2011-01-01

    Full Text Available Objective. The purpose of this study was to evaluate caries and dental fluorosis among Mexican preschoolers and school-aged children in a non-endemic zone for fluorosis and to measure its biological indicators. Methods. DMFT, DMFS, dmft, dmfs, and CDI indexes were applied. Fluoride urinary excretion and fluoride concentrations in home water, table salt, bottled water, bottled drinks, and toothpaste were determined. Results. Schoolchildren presented fluorosis (CDI = 0.96 and dental caries (DMFT = 2.64 and DMFS = 3.97. Preschoolers presented dmft = 4.85 and dmfs = 8.80. DMFT and DMFS were lower in children with mild to moderate dental fluorosis (DF. Variable fluoride concentrations were found in the analyzed products (home water = 0.18–0.44 ppm F, table salt = 0–485 ppm F, bottled water = 0.18–0.47 ppm F, juices = 0.08–1.42 ppm F, nectars = 0.07–1.30 ppm F, bottled drinks = 0.10–1.70 ppm F, toothpaste = 0–2,053 ppm F. Mean daily fluoride excretion was 422 ± 176 µg/24 h for schoolchildren and 367 ± 150 µg/24 h for preschoolers. Conclusions. Data from our study show that, despite values of excretion within an optimal fluoride intake range, the prevalence of caries was significant in both groups, and 60% of the 11- to 12-year-old children presented with dental fluorosis. In addition, variable fluoride concentrations in products frequently consumed by children were found.

  3. Fluoride in groundwater: toxicological exposure and remedies.

    Science.gov (United States)

    Jha, S K; Singh, R K; Damodaran, T; Mishra, V K; Sharma, D K; Rai, Deepak

    2013-01-01

    Fluoride is a chemical element that is found most frequently in groundwater and has become one of the most important toxicological environmental hazards globally. The occurrence of fluoride in groundwater is due to weathering and leaching of fluoride-bearing minerals from rocks and sediments. Fluoride when ingested in small quantities (dental health by reducing dental caries, whereas higher concentrations (>1.5 mg/L) may cause fluorosis. It is estimated that about 200 million people, from among 25 nations the world over, may suffer from fluorosis and the causes have been ascribed to fluoride contamination in groundwater including India. High fluoride occurrence in groundwaters is expected from sodium bicarbonate-type water, which is calcium deficient. The alkalinity of water also helps in mobilizing fluoride from fluorite (CaF2). Fluoride exposure in humans is related to (1) fluoride concentration in drinking water, (2) duration of consumption, and (3) climate of the area. In hotter climates where water consumption is greater, exposure doses of fluoride need to be modified based on mean fluoride intake. Various cost-effective and simple procedures for water defluoridation techniques are already known, but the benefits of such techniques have not reached the rural affected population due to limitations. Therefore, there is a need to develop workable strategies to provide fluoride-safe drinking water to rural communities. The study investigated the geochemistry and occurrence of fluoride and its contamination in groundwater, human exposure, various adverse health effects, and possible remedial measures from fluoride toxicity effects.

  4. A Deep Morphological Characterization and Comparison of Different Dental Restorative Materials

    Directory of Open Access Journals (Sweden)

    R. Condò

    2017-01-01

    Full Text Available Giomer is a relatively new class of restorative material with aesthetics, handling and physical properties of composite resins, and benefits of glass ionomers: high radiopacity, antiplaque effect, fluoride release, and recharge. To verify the superior properties of Giomers, in this study, a deep morphological characterization has been performed with an in vitro comparative study among a Giomer (Beautifil® II by Shofu Dental Corporation, Osaka, Japan, a Compomer (Dyract Extra by Dentsply, Caulk, Germany, glass ionomer cement (Ketac fil plus by 3M ESPE, and a composite resin (Tetric Evoceram by Ivoclar. In particular, mechanical and optical properties and ageing effects have been compared to investigate materials similarities and differences. Indentation tests, UV-Visible spectroscopy, Raman spectroscopy, and weight loss after storage in saliva or sugary drink have been carried out to analyze materials behavior in real conditions. The results confirm the high quality of Giomer material and indicate possible improvements in their usage.

  5. The potential of dental-protective chewing gum in oral health interventions.

    Science.gov (United States)

    Ly, Kiet A; Milgrom, Peter; Rothen, Marilynn

    2008-05-01

    The authors provide an overview of chewing gum as a delivery vehicle for dental-protective agents, highlighting xylitol and its potential application in caries-prevention programs for children. The authors reviewed selected clinical investigations and previous reviews associated with chewing gum containing substances such as calcium, bicarbonate, carbamide, chlorhexidine, fluoride and xylitol and their effects on reducing caries. They searched the MEDLINE database by using the key words "dental caries," "oral health," "calcium," "bicarbonate," "carbamide," "chlorhexidine," "fluoride" and "xylitol." Chewing gum is being used as a delivery vehicle for substances such as calcium, bicarbonate, carbamide, chlorhexidine, fluoride and xylitol to improve oral health and reduce caries. These substances exhibit properties that are protective of the oral environment and mediate common oral diseases. The debate for advocating xylitol use in caries prevention is advancing; however, chewing gum use by young schoolchildren in the United States is hindered by choking hazard concerns and lack of specific xylitol dosing recommendations. The use of chewing gum containing dental-protective substances, particularly xylitol, in caries-prevention programs can reduce the tooth decay epidemic. Chewing gum use by children in the school setting should be reconsidered.

  6. Fluoride level in saliva after bonding orthodontic brackets with a fluoride containing adhesive

    NARCIS (Netherlands)

    Ogaard, B; Arends, J; Helseth, H; Dijkman, G; vanderKuijl, M

    The fluoride level in saliva is considered an important parameter in caries prevention. Elevation of the salivary fluoride level by a fluoride-releasing orthodontic bonding adhesive would most likely be beneficial in the prevention of enamel caries. In this study, the fluoride level in saliva was

  7. THE USE OF FLUORIDE CONTAINING MINERAL WATER IN WORT PRODUCTION

    Directory of Open Access Journals (Sweden)

    Gunka Yonkova

    2011-12-01

    Full Text Available The present work aims to study the quality of wort produced using fluoride containing mineral water. The results show that the mineral water has a negative impact on the enzymatic destruction of starch, proteins, color intensity and pH of the wort. The changes of pH during mashing process using tap and mineral water was studied. The lower acidity of wort obtained using mineral water didn’t change during the brewing process. The fluoride content of beer is lower than 5 mg.L-1 when wort is produced using mineral and tap water in 1:1 ratio and citric acid for pH correction. At the same time, the final degree of fermentation, α-amine nitrogen content and the intensity of color of produced wort are close to the control sample. The changes in fluoride ion concentration are monitored using ion-selective potentiometry. The fluoride content is decreased from 5.7 to 4.75 mg.L-1, the most intense change is observed during the mashing process.

  8. Fluoride Rinses, Gels and Foams

    DEFF Research Database (Denmark)

    Twetman, Svante; Keller, Mette K

    2016-01-01

    AIM: The aim of this conference paper was to systematically review the quality of evidence and summarize the findings of clinical trials published after 2002 using fluoride mouth rinses, fluoride gels or foams for the prevention of dental caries. METHODS: Relevant papers were selected after...... (6 on fluoride mouth rinse, 10 on fluoride gel and 3 on fluoride foam); 6 had a low risk of bias while 2 had a moderate risk. All fluoride measures appeared to be beneficial in preventing crown caries and reversing root caries, but the quality of evidence was graded as low for fluoride mouth rinse......, moderate for fluoride gel and very low for acidulated fluoride foam. No conclusions could be drawn on the cost-effectiveness. CONCLUSIONS: This review, covering the recent decade, has further substantiated the evidence for a caries-preventive effect of fluoride mouth rinse, fluoride gel and foam...

  9. Corrosion behavior of Ti and TI6Al4V in citrate buffers containing fluoride ions

    Directory of Open Access Journals (Sweden)

    Anelise Marlene Schmidt

    2010-03-01

    Full Text Available The effect of fluoride ions concentration on the electrochemical behavior of Ti grade 2 and Ti6Al4V in citrate buffers was studied. Open circuit potential (OCP measurements and voltammetric studies of the samples in the fluoride containing citrate buffers revealed a dissolution process when the pH falls below 5.0 and the NaF content is higher than 0.01 M. However, in citrate pH 7.6 the materials showed a passive behavior even in 0.1 M NaF. Some micrographs of Ti grade 2 obtained after longer immersion times in citrate pH 5.0 with 0.01 M NaF showed a surface attack. EIS (Electrochemical Impedance Sprectroscopy data obtained at the OCP revealed that the film resistance decreases when the immersion time is increased in pH 5.0 containing 0.1 M NaF. In the citrate pH 7.6 the EIS data indicated a two-layer model of an oxide film consisting of a more compact inner layer and a porous outer layer. On the other hand, the EIS results in citrate pH 4.0 change significantly when the fluoride ions concentration increases from 0.01 to 0.05 M. The electrochemical data revealed that the corrosion behavior of Ti grade 2 and Ti6Al4V in the citrate buffers depends on the pH, the fluoride content and the exposure time.

  10. Comparative evaluation of fluoride release and recharge of pre-reacted glass ionomer composite and nano-ionomeric glass ionomer with daily fluoride exposure: An in vitro study

    Directory of Open Access Journals (Sweden)

    Jayanthi Mungara

    2013-01-01

    Full Text Available Aim: This in vitro study was designed to investigate the effects of daily fluoride exposures on fluoride release and recharge by prereacted glass ionomer (PRG composite and nano-ionomeric glass ionomer. Materials and Methods: Seventy-two specimens (36 of each material were prepared and by placing the restorative materials into Teflon mold. Each specimen was subjected to one of three daily treatments (n = 12: (1 No fluoride treatment (control; (2 application of a fluoride dentifrice (1,000 ppm once daily; and (3 the same regimen as (2, plus immersion in a 0.05% sodium fluoride (NaF mouth rinse (225 ppm immediately following the dentifrice application. Specimens were suspended in a storage vial containing 10 ml demineralizing solution for 6 h and transferred to a new test tube containing 10 ml remineralizing solution for 18 h. Fluoride treatments of the specimens were completed every day prior to their immersion in the demineralizing solution. Media solutions were buffered with equal volumes of total ionic strength adjustment buffer (TISAB II; fluoride levels were measured using a digital ion analyzer and fluoride electrode throughout the 21 day duration of the experiment. Results: Nano-ionomeric glass ionomer showed a better amount of fluoride release than PRG composite irrespective of the fluoride treatment supplementation (P < 0.01. Additional fluoride supplementation improved fluoride release and recharge ability for both the materials when compared to their respective control groups. The fluoride recharge for both materials did not show any sustained pattern of release. Conclusion: Nano-ionomeric glass ionomer demonstrated a greater ability to release and recharge compared with that of PRG composite.

  11. Effect of titanium tetrafluoride, amine fluoride and fluoride varnish on enamel erosion in vitro

    NARCIS (Netherlands)

    Vieira, A; Ruben, JL; Huysmans, MCDNJM

    2005-01-01

    This study aimed at evaluating the effect of 1 and 4% titanium tetrafluoride (TiF4) gels, amine fluoride (AmF) 1 and 0.25% and a fluoride varnish (FP) on the prevention of dental erosion. Two experimental groups served as controls, one with no pretreatment and another one pre-treated with a

  12. Dental fluorosis in populations from Chiang Mai, Thailand with different fluoride exposures - Paper 2: The ability of fluorescence imaging to detect differences in fluorosis prevalence and severity for different fluoride intakes from water

    Science.gov (United States)

    2012-01-01

    Background To assess the ability of fluorescence imaging to detect a dose response relationship between fluorosis severity and different levels of fluoride in water supplies compared to remote photographic scoring in selected populations participating in an observational, epidemiological survey in Chiang Mai, Thailand. Methods Subjects were male and female lifetime residents aged 8-13 years. For each child the fluoride content of cooking water samples (CWS) was assessed to create categorical intervals of water fluoride concentration. Fluorescence images were taken of the maxillary central incisors and analyzed for dental fluorosis using two different software techniques. Output metrics for the fluorescence imaging techniques were compared to TF scores from blinded photographic scores obtained from the survey. Results Data from 553 subjects were available. Both software analysis techniques demonstrated significant correlations with the photographic scores. The metrics for area effected by fluorosis and the overall fluorescence loss had the strongest association with the photographic TF score (Spearman’s rho 0.664 and 0.652 respectively). Both software techniques performed well for comparison of repeat fluorescence images with ICC values of 0.95 and 0.85 respectively. Conclusions This study supports the potential use of fluorescence imaging for the objective quantification of dental fluorosis. Fluorescence imaging was able to discriminate between populations with different fluoride exposures on a comparable level to remote photographic scoring with acceptable levels of repeatability. PMID:22908997

  13. Future perspectives of resin-based dental materials.

    Science.gov (United States)

    Jandt, Klaus D; Sigusch, Bernd W

    2009-08-01

    This concise review and outlook paper gives a view of selected potential future developments in the area of resin-based biomaterials with an emphasis on dental composites. A selection of key publications (1 book, 35 scientific original publications and 1 website source) covering the areas nanotechnology, antimicrobial materials, stimuli responsive materials, self-repairing materials and materials for tissue engineering with direct or indirect relations and/or implications to resin-based dental materials is critically reviewed and discussed. Connections between these fields and their potential for resin-based dental materials are highlighted and put in perspective. The need to improve shrinkage properties and wear resistance is obvious for dental composites, and a vast number of attempts have been made to accomplish these aims. Future resin-based materials may be further improved in this respect if, for example nanotechnology is applied. Dental composites may, however, reach a completely new quality by utilizing new trends from materials science, such as introducing nanostructures, antimicrobial properties, stimuli responsive capabilities, the ability to promote tissue regeneration or repair of dental tissues if the composites were able to repair themselves. This paper shows selected potential future developments in the area of resin-based dental materials, gives basic and industrial researchers in dental materials science, and dental practitioners a glance into the potential future of these materials, and should stimulate discussion about needs and future developments in the area.

  14. Corrosion resistant structural materials for use in lithium fluoride molten salts and thermonuclear device using it

    International Nuclear Information System (INIS)

    Kawamura, Kazutaka; Takagi, Ryuzo.

    1987-01-01

    Purpose: To provide blanket materials for thermo nuclear devices and structural materials for containers with less MHD effect and good heat exchanging efficiency. Constitution: LiF-PbF 2 is used as the liquid blanket material for moderating the MHD effect. That is, the lithium compound, in the form of a fluoride, can be made easily liquefiable being and PbF 2 is added for lowering the melting point. The reason of using the fluoride is that fluorine material is less activated by the adsorption of neutrons. Copper, phosphor bronze, nickel or nickel-based alloy, e.g., Monel metal is used as corrosion resistant structural material to LiF-PbF 2 molten salts. Use of copper as the low activating structural material can provide an excellent effect also in view of the maintenance and, further, a series of processes for purifying, separating injecting and recoverying tritium can be conducted safely and stationarily without contaminating the circumferences. (Kamimura, M.)

  15. The Effect of Calcium Pre-Rinse on Salivary Fluoride After 900 ppm Fluoride Mouthwash: A Randomized Clinical Trial

    Directory of Open Access Journals (Sweden)

    Nahid Ramazani

    2013-01-01

    Full Text Available Objective: Calcium fluoride deposit during fluoride application. Uptake and retention of fluoride by saliva depends generally on the concentration of calcium. In this study, the ef-fect of calcium pre-rinse on salivary fluoride concentration after a 900 ppm fluoride mouthwash was investigated.Materials and Methods: This cross-over double-blind randomized clinical trial was con-ducted in a girls' dormitory in Zahedan University of Medical Sciences, southeast Iran. In this study, 42 female dental students were chosen using simple randomization. During the first phase, 21 subjects (group A used fluoride rinse (F regimen and the remaining (group B used calcium pre-rinse followed immediately by fluoride rinse (Ca + F regi-men. In the second phase, participants rinsed using the mouthwashes not previously used. Prior to each phase prophylaxis was performed and no fluoridated product was used dur-ing a two-week interval between the phases. Salivary samples were taken immediately be-fore (baseline, 1 and 12 hours after rinsing. The salivary fluoride concentration was de-termined using fluoride sensitive electrode. Repeated measures ANOVA was used for sta-tistical analysis and the significance level was set at P<0.05.Results: There was significant difference between fluoride concentrations at different time points (P< 0.001. Significant differences were observed when the different time points of two regimens were examined. In contrast to this, the baseline before using F regimen and the baseline before using Ca + F regimen did not show any significance (P= 0.070.Conclusion: Pre-rinsing with calcium before fluoride is recommended because of signifi-cant increases in salivary fluoride concentration.

  16. The occurrence of fluoride in South African groundwater: A water ...

    African Journals Online (AJOL)

    The fluoride data were obtained by extracting fluoride groundwater quality data from DWAF's Water Management Systems (WMS) database. STATISTICA and ARCVIEW were used to process the data. The dental fluorosis data were obtained from a field study conducted by the Department of Health. The degree of dental ...

  17. In vitro enamel remineralization capacity of composite resins containing sodium trimetaphosphate and fluoride.

    Science.gov (United States)

    Tiveron, Adelisa Rodolfo Ferreira; Delbem, Alberto Carlos Botazzo; Gaban, Gabriel; Sassaki, Kikue Takebayashi; Pedrini, Denise

    2015-11-01

    This study evaluated the in vitro enamel remineralization capacity of experimental composite resins containing sodium trimetaphosphate (TMP) combined or not with fluoride (F). Bovine enamel slabs were selected upon analysis of initial surface hardness (SH1) and after induction of artificial carious lesions (SH2). Experimental resins were as follows: resin C (control—no sodium fluoride (NaF) or TMP), resin F (with 1.6% NaF), resin TMP (with 14.1% TMP), and resin TMP/F (with NaF and TMP). Resin samples were made and attached to enamel slabs (n = 12 slabs per material). Those specimens (resin/enamel slab) were subjected to pH cycling to promote remineralization, and then final surface hardness (SH3) was measured to calculate the percentage of surface hardness recovery (%SH). The integrated recovery of subsurface hardness (ΔKHN) and F concentration in enamel were also determined. Data was analyzed by ANOVA and Student-Newman-Keuls test (p Resins F and TMP/F showed similar SH3 values (p = 0.478) and %SH (p = 0.336) and differed significantly from the other resins (p resin TMP/F presented the lowest area of lesion (p resins (p = 0.042), but higher than in the other resins (p composite resin enhanced its capacity for remineralization of enamel in vitro. The combination of two agents with action on enamel favored remineralization, suggesting that composite resins containing sodium trimetaphosphate and fluoride could be indicated for clinical procedures in situations with higher cariogenic challenges.

  18. Readability of websites containing information on dental implants.

    Science.gov (United States)

    Jayaratne, Yasas S N; Anderson, Nina K; Zwahlen, Roger A

    2014-12-01

    It is recommended that health-related materials for patients be written at sixth grade level or below. Many websites oriented toward patient education about dental implants are available, but the readability of these sites has not been evaluated. To assess readability of patient-oriented online information on dental implants. Websites containing patient-oriented information on dental implants were retrieved using the Google search engine. Individual and mean readability/grade levels were calculated using standardized formulas. Readability of each website was classified as easy (≤ 6th-grade level) or difficult (≥ 10th grade level). Thirty nine websites with patient-oriented information on dental implant were found. The average readability grade level of these websites was 11.65 ± 1.36. No website scored at/below the recommended 6th grade level. Thirty four of 39 websites (87.18%) were difficult to read. The number of characters, words, and sentences on these sites varied widely. All patient-oriented websites on dental implants scored above the recommended grade level, and majority of these sites were "difficult" in their readability. There is a dire need to create patient information websites on implants, which the majority can read. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  19. Reducing dental plaque formation and caries development. A review of current methods and implications for novel pharmaceuticals.

    Science.gov (United States)

    Kalesinskas, Povilas; Kačergius, Tomas; Ambrozaitis, Arvydas; Pečiulienė, Vytautė; Ericson, Dan

    2014-01-01

    Dental caries is an oral disease, which has a high worldwide prevalence despite the availability of various prophylactic means, including the daily use of fluoride toothpastes, water fluoridation, dental sealants, oral health educational programs and various antiseptic mouth-rinses. One important reason for this is uncontrolled increase in consumption of foods containing considerable sucrose concentration, especially among children. Sucrose is easily metabolized by oral bacteria (mostly streptococci) to acids and, subsequently, causing tooth decay or dental caries. In the oral ecosystem, streptococci principally reside on tooth surfaces forming biofilm. Important structural and binding materials of biofilm are glucan polymers synthesized by several isoforms of glucosyltransferase enzyme present in certain species of oral bacteria, including mutans group streptococci - Streptococcus mutans and Streptococcus sobrinus, which preferably colonize humans. Thus, there is a constant need to develop the methods and chemotherapeutics for improving oral health care and decreasing teeth decay through the suppression of cariogenic biofilm formation in the oral cavity. The aim of this paper was to review literature related to the pathogenesis of dental caries as well as currently existing and experimental pharmaceutical substances used for prevention of this process.

  20. Effect of pretreatment with an Er:YAG laser and fluoride on the prevention of dental enamel erosion.

    Science.gov (United States)

    dos Reis Derceli, Juliana; Faraoni-Romano, Juliana Jendiroba; Azevedo, Danielle Torres; Wang, Linda; Bataglion, César; Palma-Dibb, Regina Guenka

    2015-02-01

    The aim of this study was to evaluate the effect of the Er:YAG laser and its association with fluoride (1.23% acidulate phosphate fluoride gel) on the prevention of enamel erosion. Sixty specimens were obtained from bovine enamel (4 × 4 mm), which were ground flat, polished, and randomly divided into five groups according to the preventive treatments: control-fluoride application; L--Er:YAG laser; L+F--laser + fluoride; F+L--fluoride + laser; L/F--laser/fluoride simultaneously. Half of the enamel surface was covered with nail varnish (control area), and the other half was pretreated with one of the preventive strategies to subsequently be submitted to erosive challenge. When the laser was applied, it was irradiated for 10 s with a focal length of 4 mm and 60 mJ/2 Hz. Fluoride gel was applied for 4 min. Each specimen was individually exposed to regular Coca-Cola® for 1 min, four times/day, for 5 days. Wear analysis was performed with a profilometer, and demineralization was assessed with an optical microscope. Data were analyzed using the Kruskal-Wallis test (wear)/Dunn test and ANOVA/Fisher's exact tests. The group L/F was similar to control group. The other groups showed higher wear, which did not present differences among them. In the demineralization assessment, the groups F+L and L/F showed lower demineralization in relation to the other groups. It can be concluded that none preventive method was able to inhibit dental wear. The treatments L/F and F+L showed lower enamel demineralization.

  1. Corrosion resistant materials for fluorine and hydrogen fluoride

    International Nuclear Information System (INIS)

    Hauffe, K.

    1984-01-01

    Aluminum and Duralumin are resistant against fluorine and hydrogen fluoride up to 600 and 700 K, respectively. The resistance of nickel and its alloys, particularly monel, against fluorine and hydrogen fluoride is fairly good up to 900 and 800 K. During the attack of nickel-chromium alloys by fluorine between 1000 and 1300 K, it appears an inner fluorination similarly to the inner oxidation. The resistance of titanium in water-free liquid fluorine at lower temperatures with -1 is comparable to that of nickel and monel. However, the corrosion of titanium in gaseous fluorine amounts at 377 K only 0,0082 mm.a -1 . In spite of their limited resistance against fluorine and hydrogen fluoride, very pure molybdenum and tungsten are employed as construction materials in the rocket technology because of their large strength at high temperatures if fluorine-hydrogen and fluorine-hydrazine flames are used. Lanthanum and calcium borides are only little attacked by fluorine hydrazine flames between 1400 and 1800 K; they are superior to all special grade alloys. The same is true in a lower temperature region (290-400 K) with fluorcarbon resins. Organic materials substitute in increasing extent metal alloys and non-metal inorganic materials. (orig.) [de

  2. Corrosion resistant materials for fluorine and hydrogen fluoride

    Energy Technology Data Exchange (ETDEWEB)

    Hauffe, K.

    1984-12-01

    Aluminum and Duralumin are resistant against fluorine and hydrogen fluoride up to 600 and 700 K, respectively. The resistance of nickel and its alloys, particularly monel, against fluorine and hydrogen fluoride is fairly good up to 900 and 800 K. During the attack of nickel-chromium alloys by fluorine between 1000 and 1300 K, it appears an inner fluorination similarly to the inner oxidation. The resistance of titanium in water-free liquid fluorine at lower temperatures with <0,3 mm.a/sup -1/ is comparable to that of nickel and monel. However, the corrosion of titanium in gaseous fluorine amounts at 377 K only 0,0082 mm.a/sup -1/. In spite of their limited resistance against fluorine and hydrogen fluoride, very pure molybdenum and tungsten are employed as construction materials in the rocket technology because of their large strength at high temperatures if fluorine-hydrogen and fluorine-hydrazine flames are used. Lanthanum and calcium borides are only little attacked by fluorine hydrazine flames between 1400 and 1800 K; they are superior to all special grade alloys. The same is true in a lower temperature region (290-400 K) with fluorcarbon resins. Organic materials substitute in increasing extent metal alloys and non-metal inorganic materials.

  3. Probing ge distribution in zeolite frameworks by post-synthesis introduction of fluoride in as-made materials

    KAUST Repository

    Liu, Xiaolong

    2012-08-14

    A new method has been developed to introduce fluoride in the structure of as-made germanium-containing zeolites prepared under pure alkaline media. Incorporation of fluoride species occurs without modification of the framework composition (Si/Ge ratio) and of the crystallinity, as evidenced by X-ray diffraction and electron microscopy. After incorporation, 19F solid-state NMR has been used to probe the location and distribution of Ge atoms in the framework. In the case of ITQ-13 and ITQ-17, which can be prepared from both hydroxide and fluoride routes, incorporated F anions are located in the same structural units as those occupied when zeolites are prepared in the presence of fluoride. In the case of ITQ-22 and ITQ-24, fluoride goes mainly in D4R units, which appear to be in the most energetically favorable positions for these zeolites. All experiments clearly show that zeolites prepared in the absence of fluoride in the synthesis medium are enriched in germanium, compared to the same materials obtained from F-containing gels. Moreover, Ge plays a strong structure-directing role by replacing Si atoms preferentially in D4R, leading to zeolites with mainly [4Si, 4Ge] units in the framework. In the particular case of ITQ-22, a new line observed around -2 ppm in 19F NMR spectra has been tentatively assigned to [3Si, 5Ge] D4R units, which corroborates the structural data obtained via X-ray diffraction. © 2012 American Chemical Society.

  4. Fluoride removal performance of phosphoric acid treated lime ...

    African Journals Online (AJOL)

    Fluoride in drinking water above permissible levels is responsible for dental and skeletal fluorosis. In this study, removal of fluoride ions from water using phosphoric acid treated lime was investigated in continuous and point-of-use system operations. In the continuous column operations, fluoride removal performance was ...

  5. Fluoride exposure and indicators of thyroid functioning in the Canadian population: implications for community water fluoridation.

    Science.gov (United States)

    Barberio, Amanda M; Hosein, F Shaun; Quiñonez, Carlos; McLaren, Lindsay

    2017-10-01

    There are concerns that altered thyroid functioning could be the result of ingesting too much fluoride. Community water fluoridation (CWF) is an important source of fluoride exposure. Our objectives were to examine the association between fluoride exposure and (1) diagnosis of a thyroid condition and (2) indicators of thyroid functioning among a national population-based sample of Canadians. We analysed data from Cycles 2 and 3 of the Canadian Health Measures Survey (CHMS). Logistic regression was used to assess associations between fluoride from urine and tap water samples and the diagnosis of a thyroid condition. Multinomial logistic regression was used to examine the relationship between fluoride exposure and thyroid-stimulating hormone (TSH) level (low/normal/high). Other available variables permitted additional exploratory analyses among the subset of participants for whom we could discern some fluoride exposure from drinking water and/or dental products. There was no evidence of a relationship between fluoride exposure (from urine and tap water) and the diagnosis of a thyroid condition. There was no statistically significant association between fluoride exposure and abnormal (low or high) TSH levels relative to normal TSH levels. Rerunning the models with the sample constrained to the subset of participants for whom we could discern some source(s) of fluoride exposure from drinking water and/or dental products revealed no significant associations. These analyses suggest that, at the population level, fluoride exposure is not associated with impaired thyroid functioning in a time and place where multiple sources of fluoride exposure, including CWF, exist. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  6. Non-ferrous metals, anorganic and organic materials resistent to fluorides

    International Nuclear Information System (INIS)

    Hauffe, K.

    1986-01-01

    Aluminium and its alloys are resistant in fluoride solutions up to 400 K. Aluminium is also a suitable reactor material for the thermal decomposition of acidic fluorides between 750 and 825 K. Brass corrodes at room temperature in a 0,1 m KF solution with and without inhibitors very slowly ( -1 ). Nickel and the nickel alloys Inconel 600, Hastelloy N and Monel 500 are the most resistant materials against fluoride solutions and melts. A similar behavior exhibit zirconium-titanium-iron and zirconium-titanium-molybdenum alloys, respectively. From the inorganic compounds, compressed graphite, Al 2 O 3 and hexaborides of earth and rare earth metals, particularly LaB 6 , are extraordinarily resistant against fluorine ions at high temperatures. If the reaction temperature remains below 370 K, then polymers and resins, e.g. polyolefines, PVC, acrylic and epoxy resins and fluorcarbon resins can be employed as coating or compound material (resin + carbon fibers) resistant against fluorine ions up to 370 K. (orig.) [de

  7. SULPHUR DIOXIDE LEACHING OF URANIUM CONTAINING MATERIAL

    Science.gov (United States)

    Thunaes, A.; Rabbits, F.T.; Hester, K.D.; Smith, H.W.

    1958-12-01

    A process is described for extracting uranlum from uranium containing material, such as a low grade pitchblende ore, or mill taillngs, where at least part of the uraniunn is in the +4 oxidation state. After comminuting and magnetically removing any entrained lron particles the general material is made up as an aqueous slurry containing added ferric and manganese salts and treated with sulfur dioxide and aeration to an extent sufficient to form a proportion of oxysulfur acids to give a pH of about 1 to 2 but insufficient to cause excessive removal of the sulfur dioxide gas. After separating from the solids, the leach solution is adjusted to a pH of about 1.25, then treated with metallic iron in the presence of a precipitant such as a soluble phosphate, arsonate, or fluoride.

  8. Urinary fluoride excretion in preschool children after intake of fluoridated milk and use of fluoride-containing toothpaste

    DEFF Research Database (Denmark)

    Norman, M; Twetman, S; Hultgren Talvilahti, A

    2017-01-01

    Objective: To assess the urinary fluoride excretion in preschool children after drinking fluoridated milk with 0.185 mg F and 0.375 mg F and to study the impact of use of fluoride toothpaste. Basic research design: Double-blind cross-over study. Participants: Nine healthy children, 2.5-4.5 years...

  9. Comparative Evaluation of Fluoride Releasing Ability of Various Restorative Materials after the Application of Surface Coating Agents - An In-vitro Study.

    Science.gov (United States)

    Kishore, Gvs; Sai-Sankar, A J; Pratap-Gowd, Mjs; Sridhar, M; Pranitha, Kakarla; Sai-Krishna, V S

    2016-12-01

    Fluoride plays a key role in prevention of dental caries and is also an essential element for oral health promotion both in children and adults. The aim of the present study was to evaluate the effect of surface coating (petroleum jelly, G-Coat Plus) on the fluoride releasing property of conventional Glass Ionomer Cement (GIC) and Zirconomer. A total of 30 disk shaped brass mold specimens (6±0.1mm in diameter and 2±0.1mm thickness) for each test group were fabricated with conventional GIC (Group A) and Zirconomer (Group B). These test groups were further divided into three subgroups of 10 each. The unprotected specimens act as control (Group A1 and B1), G-Coat Plus specimens as (Group A2 and B2) and for the remaining specimens petroleum jelly was applied (Group A3 and B3). Fluoride ion concentration was measured with a combination of fluoride ion specific electrode and ion analyzer for every 24 hours for 15 days. The data was statistically analyzed using Kruskal Wallis and Mann-Whitney U test. The Group B released significantly more fluoride than Group A. Among all the subgroups the greatest amount of fluoride was released from Group B1, in the first 24 hours followed by A1 and B2. The least was observed on 15 th day with Group B3 and A3. Both the tested materials (GIC and Zirconomer) used in the study exhibited fluoride release whether protected or unprotected with surface coating. Though there was a difference between the groups, the pattern of fluoride release was similar and continuous throughout the study period i.e., first the initial burst followed by sustained release. The results revealed Zirconomer released more fluoride and is comparable to conventional GIC.

  10. some factors influencing the free fluoride content in black tea

    African Journals Online (AJOL)

    ACSS

    Fluoride is an essential micro-nutrient owing to its role in the prevention of dental caries. Chronic exposure to high levels of the ion (F-) results in both dental and skeletal fluorosis. A study was carried out to determine free fluoride content in tea (Camellia sinensis) infusions of different grades of black Cut, Tear and Curl ...

  11. Potential fluoride toxicity from oral medicaments: A review

    OpenAIRE

    Rizwan Ullah; Muhammad Sohail Zafar; Nazish Shahani

    2017-01-01

    The beneficial effects of fluoride on human oral health are well studied. There are numerous studies demonstrating that a small amount of fluoride delivered to the oral cavity decreases the prevalence of dental decay and results in stronger teeth and bones. However, ingestion of fluoride more than the recommended limit leads to toxicity and adverse effects. In order to update our understanding of fluoride and its potential toxicity, we have described the mechanisms of fluoride metabolism, tox...

  12. Comparison of Antibacterial Effect of Fluoride and Chlorhexidine on Two Cariogenic Bacteria: An in Vitro Study

    OpenAIRE

    Poureslami HR; Barkam F; Poureslami P; Salari Z; Salari S

    2014-01-01

    Statement of problem: Dental plaque is the main source for dental caries and there is no proper vaccine that can affect dental plaques. Objectives: Daily use of an efficient anti-plaque product can be very beneficial in plaque control and, thus, prevention of caries. This study aims to evaluate the antibacterial effects of four products of Chlorhexidine and Fluoride on two types of cariogenic bacteria. Materials and Methods: In this in vitro study, the antibacterial effect of Chlorhe...

  13. Tribology of dental materials: a review

    International Nuclear Information System (INIS)

    Zhou, Z R; Zheng, J

    2008-01-01

    The application of tribology in dentistry is a growing and rapidly expanding field. Intensive research has been conducted to develop an understanding of dental tribology for successful design and selection of artificial dental materials. In this paper, the anatomy and function of human teeth is presented in brief, three types of current artificial dental materials are summarized, and their advantages and disadvantages, as well as typical clinical applications, are compared based on the literature. Possible tribological damage of tooth structure, which is induced by complex interfacial motion, and friction-wear test methods are reported. According to results obtained by the authors and from the literature, the main progress in the area of dental tribology on both natural teeth and artificial dental materials is reviewed. Problems and challenges are discussed and future research directions for dental tribology are recommended. (topical review)

  14. Tribology of dental materials: a review

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Z R; Zheng, J [Tribology Research Institute, Key Laboratory for Advanced Technology of Materials of Ministry of Education, Southwest Jiaotong University, Chengdu 610031 (China)], E-mail: zrzhou@home.swjtu.edu.cn

    2008-06-07

    The application of tribology in dentistry is a growing and rapidly expanding field. Intensive research has been conducted to develop an understanding of dental tribology for successful design and selection of artificial dental materials. In this paper, the anatomy and function of human teeth is presented in brief, three types of current artificial dental materials are summarized, and their advantages and disadvantages, as well as typical clinical applications, are compared based on the literature. Possible tribological damage of tooth structure, which is induced by complex interfacial motion, and friction-wear test methods are reported. According to results obtained by the authors and from the literature, the main progress in the area of dental tribology on both natural teeth and artificial dental materials is reviewed. Problems and challenges are discussed and future research directions for dental tribology are recommended. (topical review)

  15. Caregivers who refuse preventive care for their children: the relationship between immunization and topical fluoride refusal.

    Science.gov (United States)

    Chi, Donald L

    2014-07-01

    The aim of this study was to examine caregivers' refusal of preventive medical and dental care for children. Prevalence rates of topical fluoride refusal based on dental records and caregiver self-reports were estimated for children treated in 3 dental clinics in Washington State. A 60-item survey was administered to 1024 caregivers to evaluate the association between immunization and topical fluoride refusal. Modified Poisson regression models were used to estimate prevalence rate ratios (PRRs). The prevalence of topical fluoride refusal was 4.9% according to dental records and 12.7% according to caregiver self-reports. The rate of immunization refusal was 27.4%. In the regression models, immunization refusal was significantly associated with topical fluoride refusal (dental record PRR = 1.61; 95% confidence interval [CI] = 1.32, 1.96; P refuse both immunizations and topical fluoride (P refusal of immunizations is associated with topical fluoride refusal. Future research should identify the behavioral and social factors related to caregiver refusal of preventive care with the goal of developing multidisciplinary strategies to help caregivers make optimal preventive care decisions for children.

  16. Parents' attitudes towards topical fluoride and vaccines for children: Are these distinct or overlapping phenomena?

    Directory of Open Access Journals (Sweden)

    Richard M. Carpiano

    2018-06-01

    Full Text Available Despite attention paid to parental refusal of child vaccines, the phenomenon of topical fluoride refusal is poorly understood. We examine the extent to which parent attitudes and Internet use regarding topical fluoride treatment and vaccines may overlap and, in turn, uniquely or distinctly correlate with fluoride and vaccine refusal for the child. In 2017, we analyzed data collected from 2011 to 12 for 361 children from three Washington state dental clinics. The instrument included analogous measures of topical fluoride and vaccine safety concerns, perceived severity of preventable cavities/disease, and Internet use for fluoride/vaccine information; and measures of non-fluoridated toothpaste use, attitudes towards dental x-rays and amalgam and composite fillings. We assessed dental chart-based topical fluoride refusal occurring in 2009 or 2010 and parent-reported vaccine refusal. All analogous fluoride and vaccine items were substantively correlated. However, in a series of adjusted models, none of these items were significantly associated with fluoride refusal. Multiple fluoride and vaccine items were associated with vaccine refusal in unadjusted models; but only vaccine safety concerns, perceived severity of a preventable cavity, and Internet use for vaccine information remained significant in adjusted models. Although there is concordance between the two refusal behaviors as well as analogous attitudes and Internet use, these findings challenge the idea that fluoride refusal should be addressed with interventions focusing on vaccine refusal. Further research is required on the factors underlying refusal of preventive dental care. Keywords: Vaccinations, Topical fluoride, Vaccination refusal, Fluoride refusal, Vaccine hesitancy, Fluoride hesitancy, Children, Adolescents, Preventive treatment, United States

  17. Evaluation of the remineralization capacity of CPP-ACP containing fluoride varnish by different quantitative methods

    Directory of Open Access Journals (Sweden)

    Selcuk SAVAS

    Full Text Available ABSTRACT Objective The aim of this study was to evaluate the efficacy of CPP-ACP containing fluoride varnish for remineralizing white spot lesions (WSLs with four different quantitative methods. Material and Methods Four windows (3x3 mm were created on the enamel surfaces of bovine incisor teeth. A control window was covered with nail varnish, and WSLs were created on the other windows (after demineralization, first week and fourth week in acidified gel system. The test material (MI Varnish was applied on the demineralized areas, and the treated enamel samples were stored in artificial saliva. At the fourth week, the enamel surfaces were tested by surface microhardness (SMH, quantitative light-induced fluorescence-digital (QLF-D, energy-dispersive spectroscopy (EDS and laser fluorescence (LF pen. The data were statistically analyzed (α=0.05. Results While the LF pen measurements showed significant differences at baseline, after demineralization, and after the one-week remineralization period (p0.05. With regards to the SMH and QLF-D analyses, statistically significant differences were found among all the phases (p<0.05. After the 1- and 4-week treatment periods, the calcium (Ca and phosphate (P concentrations and Ca/P ratio were higher compared to those of the demineralization surfaces (p<0.05. Conclusion CPP-ACP containing fluoride varnish provides remineralization of WSLs after a single application and seems suitable for clinical use.

  18. Combined effect of fluoride and 2,3,7,8-tetrachlorodibenzo-p-dioxin on mouse dental hard tissue formation in vitro.

    Science.gov (United States)

    Salmela, Eija; Lukinmaa, Pirjo-Liisa; Partanen, Anna-Maija; Sahlberg, Carin; Alaluusua, Satu

    2011-08-01

    Fluoride interferes with enamel matrix secretion and mineralization and dentin mineralization. The most toxic dioxin congener, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), also impairs dental hard tissue formation and mineralization in vitro and in vivo. Our aim was to investigate in vitro whether the combined effect of sodium fluoride (NaF) and TCDD on dental hard tissue formation is potentiative. For this purpose, mandibular first and second molar tooth germs of E18 mouse embryos were cultured for 5-12 days with NaF and TCDD alone at various concentrations (2.5, 5, 10, 12.5, 15, and 20 μM and 5, 10, 12.5, and 15 nM, respectively) to determine the highest concentrations, which alone cause no or negligible effects. Morphological changes were studied from the whole tooth photographs and histological tissue sections. The concentrations found were 15 μM for NaF and 10 nM for TCDD. While at these concentrations, the effects of NaF and TCDD alone were barely detectable, the effect of simultaneous exposure on dentin and enamel formation was overt; mineralization of predentin to dentin and enamel matrix secretion and mineralization were impaired. Immunohistochemical analysis revealed that the combined exposure modified amelogenin expression by odontoblasts. Morphology of ameloblasts and the expression of amelogenin indicated that ameloblasts were still secretory. The results show that NaF and TCDD have potentiative, harmful effects on the formation of dental hard tissues. Since children can be exposed to subclinical levels of fluoride and dioxins during early childhood, coincidently with mineralization of the first permanent teeth, this finding may have clinical significance.

  19. INTERACTION OF FLUORIDE COMPLEXES DERIVED FROM GLASS-IONOMER CEMENTS WITH HYDROXYAPATITE

    Directory of Open Access Journals (Sweden)

    Lewis S. M.

    2013-09-01

    Full Text Available A study has been undertaken of the interaction of complexed fluoride extracted from glass-ionomer dental cements with synthetic hydroxyapatite powder. Extracts were prepared from two commercial glass-ionomers (Fuji IX and ChemFlex under both neutral and acidic conditions. They were analysed by ICP-OES and by fluoride-ion selective electrode with and without added TISAB to decomplex the fluoride. The pH of the acid extracts was 4, conditions under which fluoride complexes with protons as HF or HF2-, it also complexes with aluminium, which was found to be present in higher amounts in the acid extracts. Fluoride was found to be almost completely complexed in acid extracts, but not in neutral extracts, which contained free fluoride ions. Exposure of these extracts to synthetic hydroxyapatite powder showed that fluoride was taken up rapidly (within 5 minutes, whether or not it was complexed. SEM (EDAX study of recovered hydroxyapatite showed only minute traces of aluminium taken up under all conditions. This showed that aluminium interacts hardly at all with hydroxyapatite, and hence is probably not involved in the remineralisation process.

  20. Evaluation of radiation effects on dental enamel hardness and dental restorative materials

    International Nuclear Information System (INIS)

    Adachi, Lena Katekawa; Saiki, Mitiko; Campos, Tomie Nakakuki

    2000-01-01

    This research presents the results of the microhardness of human dental enamel and of the following dental restorative materials: three dental porcelains - Ceramco II, Finesse and Noritake, and two resin restorative materials - Artglass and Targis, for materials submitted to different times of irradiation at the IEA-R1m nuclear reactor under a thermal neutron flux of 10 12 n cm -2 .s -1 . The results obtained indicated that there is a decrease of the surface microhardness when the enamel is irradiated for 1 h and when dental materials are irradiated for 3 h. However, enamels irradiated for 30 min. did not show significant change of their surface hardness. Therefore, the selection of irradiation time is an important factor to be considered when irradiated teeth or dental materials are used in the investigations of their properties. (author)

  1. Disparities in children's oral health and access to dental care.

    Science.gov (United States)

    Mouradian, W E; Wehr, E; Crall, J J

    Dental caries can be prevented by a combination of community, professional, and individual measures including water fluoridation, professionally applied topical fluorides and dental sealants, and use of fluoride toothpastes. Yet, tooth decay is the most common chronic disease of childhood. Dental care is the most prevalent unmet health need in US children with wide disparities existing in oral health and access to care. Only 1 in 5 children covered by Medicaid received preventive oral care for which they are eligible. Children from low income and minority families have poorer oral health outcomes, fewer dental visits, and fewer protective sealants. Water fluoridation is the most effective measure in preventing caries, but only 62% of water supplies are fluoridated, and lack of fluoridation may disproportionately affect poor and minority children. Childhood oral disease has significant medical and financial consequences that may not be appreciated because of the separation of medicine and dentistry. The infectious nature of dental caries, its early onset, and the potential of early interventions require an emphasis on preventive oral care in primary pediatric care to complement existing dental services. However, many pediatricians lack critical knowledge to promote oral health. We recommend financial incentives for prioritizing Medicaid Early and Periodic Screening, Diagnostic, and Treatment dental services; managed care accountability; integration of medical and dental professional training, clinical care, and research; and national leadership. JAMA. 2000;284:2625-2631.

  2. Liberação de flúor de materiais restauradores Fluoride releasing of restorative materials

    Directory of Open Access Journals (Sweden)

    Adriana Silva de CARVALHO

    1998-10-01

    -DENTSPLY (VAR, Dyract-DENTSPLY (DYR and Tetric-VIVADENT (TET. Six cylindrical samples (area = 1.65 cm2 of each material were prepared; each sample was then suspended individually in a plastic tube containing 2.0 mL of deionized water. The water was changed daily during 15 days. Fluoride release was determined after buffering the solution with an equal volume of TISABII. For the fluoride analysis, a fluoride electrode, Orion 96-09, and an ionalyser Orion EA 940 were used. All materials showed the same pattern of fluoride release during the 15-day experiment; the greatest fluoride release occurred during the first days and then it decreased rapidly toward a constant level. The fluoride released (mean ± standard error in mg F/cm2 were: CHE = 7.62 ± 0.73A, VIT = 5.91 ± 0.79B, VAR = 2.72 ± 0.25C, DYR = 1.50 ± 0.17D, TE = 0.136 ± 0.016E. Means followed by different letters were significant (5%. The results showed that the composition of restorative materials influenced significantly the fluoride release.

  3. Studies on the comparative effect of sodium fluoride on collagen ...

    African Journals Online (AJOL)

    Fluoride is an essential element for the normal development and growth of human beings. The main source of fluoride for humans is the intake of groundwater. At high levels, fluoride causes dental and skeletal fluorosis. In this study, control and sodium fluoride (NaF) treated groups of rats had significant (p < 0.05) higher ...

  4. The 1/4 technical scale, continuous process of obtaining the ceramic uranium dioxide from ammonium polyuranates containing fluoride

    International Nuclear Information System (INIS)

    Wlodarski, R.

    1977-01-01

    Based on the laboratory results, the 1/4 technical apparatus for the continuous reduction and defluorination of ammonium polyuranate containing fluoride was designed and constructed. The possibility of obtaining the ceramic uranium dioxide in a continuous process has been confirmed. The main part of the apparatus used in this process was the horizontal tubular oven with the extruder transporting material. (author)

  5. Separative recovery with lime of phosphate and fluoride from an acidic effluent containing H3PO4, HF and/or H2SiF6.

    Science.gov (United States)

    Gouider, Mbarka; Feki, Mongi; Sayadi, Sami

    2009-10-30

    Fluoride content and flow-rate of fertilizer plant wastewater from phosphoric acid and/or triple superphosphate (TSP) production lead to the discharge of several thousand tons of fluoride (F(-)) per year and even more for phosphate (PO4(3-)). Since sustainability is an important environmental concern, the removal methods should allow phosphorus and fluoride to be recycled as a sustainable products for use as raw materials either in agricultural or industrial applications. In the present work, separative recovery with lime of these two target species was investigated. A preliminary speciation study, carried out on the crude effluent, showed that two forms of fluoride: HF and H2SiF6 are present in a highly acidic medium (pH approximately 2). Evidence that fluoride is present under both free (HF) and combined (H2SiF6) forms, in the phosphate-containing effluent, was provided by comparing potentiometric titration curves of a crude wastewater sample and synthetic acid mixtures containing H3PO4, HF and H2SiF6. In a second step synthetic effluent containing mixtures of the following acids: HF, H2SiF6 and H3PO4, were treated with lime. The behaviour of these compounds under lime treatment was analysed. The data showed that fluoride has a beneficial effect on phosphate removal. Moreover, by acting on the precipitation pH, a "selective" recovery of fluoride and phosphate ions was possible either from phosphoric acid/hydrofluoric acid or phosphoric acid/hexafluorosilicic acid mixtures. Indeed, the first stage of the separative recovery, led to a fluoride removal efficiency of 97-98% from phosphoric acid/hydrofluoric acid mixture. It was of 93-95% from phosphoric acid/hexafluorosilicic acid mixture. During the second stage, the phosphate precipitation reached 99.8% from both acidic mixtures whereas it did not exceed 82% from a solution containing H3PO4 alone. The XRD and IR analyses showed that during lime treatment, a H2SiF6 hydrolysis occurred, instead of CaSiF6 solid

  6. Fluoride varnish reduces white spot lesions during orthodontic treatment.

    Science.gov (United States)

    Shafi, Imran

    2008-01-01

    This was a randomised controlled trial (RCT) set in a community dental practice. The test varnish was a commercially available product, Fluor Protector (Ivoclar Vivadent, Schaan, Liechtenstein), containing 0.1% fluoride as difluorosilane in a polyurethane varnish base. The placebo varnish applied had an identical composition but without fluoride. The incidence and prevalence of white spot lesions (WSL) on the upper incisors, cuspids and premolars were recorded, as scored from digital photographs by two independent examiners. In the case of disagreement, cases were re-examined until a consensus was achieved. The incidence of WSL during the treatment period was 7.4% in the fluoride varnish group compared with 25.3% placebo group (P <0.001). The mean progression score was significantly lower in the fluoride varnish group than in the placebo group, (0.8 +/- 2.0 vs 2.6 +/- 2.8; P <0.001). The absolute risk reduction was 18% and the number-needed-to-treat was calculated to be 5.5 (95% confidence interval, 3.7-10.9). The results strongly suggest that regular topical fluoride varnish applications may reduce the development of WSL adjacent to the bracket base during treatment with fixed appliances.

  7. Beyond food: The multiple pathways for inclusion of materials into ancient dental calculus.

    Science.gov (United States)

    Radini, Anita; Nikita, Efthymia; Buckley, Stephen; Copeland, Les; Hardy, Karen

    2017-01-01

    Dental calculus (mineralized dental plaque) was first recognised as a potentially useful archaeological deposit in the 1970s, though interest in human dental calculus as a resource material has increased sharply in the past few years. The majority of recent research has focused on the retrieval of plant microfossils embedded in its matrix and interpretation of these finds as largely the result of deliberate consumption of plant-derived food. However, while most of the material described in published works does represent food, dental calculus is in fact a "depositional environment" as material can enter the mouth from a range of sources. In this respect, it therefore represents an archaeological deposit that can also contain extensive non-dietary debris. This can comprise a wide variety of cultural and environmental material which reaches the mouth and can become embedded in dental calculus through alternative pathways. Here, we explore the human behaviors and activities besides eating that can generate a flux of particles into the human mouth, the broad range of additional cultural and environmental information that can be obtained through the analysis and contextualisation of this material, and the implications of the additional pathways by which material can become embedded in dental calculus. © 2017 American Association of Physical Anthropologists.

  8. Xylitol-containing products for preventing dental caries in children and adults.

    Science.gov (United States)

    Riley, Philip; Moore, Deborah; Ahmed, Farooq; Sharif, Mohammad O; Worthington, Helen V

    2015-03-26

    Dental caries is a highly prevalent chronic disease which affects the majority of people. It has been postulated that the consumption of xylitol could help to prevent caries. The evidence on the effects of xylitol products is not clear and therefore it is important to summarise the available evidence to determine its effectiveness and safety. To assess the effects of different xylitol-containing products for the prevention of dental caries in children and adults. We searched the following electronic databases: the Cochrane Oral Health Group Trials Register (to 14 August 2014), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library, 2014, Issue 7), MEDLINE via OVID (1946 to 14 August 2014), EMBASE via OVID (1980 to 14 August 2014), CINAHL via EBSCO (1980 to 14 August 2014), Web of Science Conference Proceedings (1990 to 14 August 2014), Proquest Dissertations and Theses (1861 to 14 August 2014). We searched the US National Institutes of Health Trials Register (http://clinicaltrials.gov) and the WHO Clinical Trials Registry Platform for ongoing trials. No restrictions were placed on the language or date of publication when searching the electronic databases. We included randomised controlled trials assessing the effects of xylitol products on dental caries in children and adults. Two review authors independently screened the results of the electronic searches, extracted data and assessed the risk of bias of the included studies. We attempted to contact study authors for missing data or clarification where feasible. For continuous outcomes, we used means and standard deviations to obtain the mean difference and 95% confidence interval (CI). We used the continuous data to calculate prevented fractions (PF) and 95% CIs to summarise the percentage reduction in caries. For dichotomous outcomes, we reported risk ratios (RR) and 95% CIs. As there were less than four studies included in the meta-analysis, we used a fixed-effect model. We planned

  9. Protective Effect of Whole and Fat-Free Fluoridated Milk, Applied before or after Acid Challenge, against Dental Erosion.

    Science.gov (United States)

    Cassiano, Luiza P S; Charone, Senda; Souza, Juliana G; Leizico, Ligia C; Pessan, Juliano P; Magalhães, Ana Carolina; Buzalaf, Marília Afonso Rabelo

    2016-01-01

    This study analysed in vitro the effect of milk against dental erosion, considering three factors: the type of milk (bovine whole/fat-free), the presence of different fluoride concentrations and the time of application (before/after erosive challenge). Bovine enamel (n = 15/group) and root dentine (n = 12/group) specimens were submitted to the following treatments: after the first erosive challenge - 0.9% NaCl solution (negative control), whole milk with 0, 2.5, 5.0 and 10.0 ppm F, fat-free milk with 0, 2.5, 5.0 and 10.0 ppm F, and 0.05% NaF solution (positive control); before the first erosive challenge - whole milk with 0, 2.5, 5.0 and 10.0 ppm F, fat-free milk with 0, 2.5, 5.0 and 10.0 ppm F, and 0.05% NaF solution (positive control). Specimens were submitted to demineralisation-remineralisation regimes 4 times/day for 5 days. The response variables were enamel and dentine loss (in micrometres). Data were analysed using Kruskal-Wallis/Dunn's test (p erosive challenge, was the most protective treatment, but with no significant difference compared with the same treatment carried out after the erosive challenge. For dentine, whole fluoridated milk (all concentrations, after), fat-free 10 ppm F milk (after, before) and whole milk with or without F (except 2.5 ppm F, all before) significantly reduced dentine erosion. It seems that the presence of fluoride, especially at 10 ppm, is the most important factor in reducing dental erosion. © 2016 S. Karger AG, Basel.

  10. Potential fluoride toxicity from oral medicaments: A review.

    Science.gov (United States)

    Ullah, Rizwan; Zafar, Muhammad Sohail; Shahani, Nazish

    2017-08-01

    The beneficial effects of fluoride on human oral health are well studied. There are numerous studies demonstrating that a small amount of fluoride delivered to the oral cavity decreases the prevalence of dental decay and results in stronger teeth and bones. However, ingestion of fluoride more than the recommended limit leads to toxicity and adverse effects. In order to update our understanding of fluoride and its potential toxicity, we have described the mechanisms of fluoride metabolism, toxic effects, and management of fluoride toxicity. The main aim of this review is to highlight the potential adverse effects of fluoride overdose and poorly understood toxicity. In addition, the related clinical significance of fluoride overdose and toxicity has been discussed.

  11. Fluoride release and surface roughness of a new glass ionomer cement: glass carbomer

    Directory of Open Access Journals (Sweden)

    Célia Maria Condeixa de França LOPES

    2018-02-01

    Full Text Available Abstract Objective This study analyzed the fluoride release/recharge and surface roughness of glass carbomer compared to other encapsulated glass ionomer cements (GICs. Material and method The GICs tested were Glass Fill® (GC-GCP Dental, Riva Self Cure® (RS-SDI, Riva Light Cure® (RL-SDI, Equia Fil® (EF-GC Europe. The composite resin Luna® (LU-SDI was used as control. Five samples of each material were prepared and kept in a humidifier for 24 hours (37 °C, 100% relative humidity. Fluoride release was measured in two times: before (T1: days 1, 2, 7, 14 and after topical application of fluoride (T2: days 15, 16, 21 and 28. The surface roughness was also measured in both times (T1: days 1 and 14; T2: days 15 and 28. All samples were submitted to a single topical application of acidulated fluoride phosphate (Fluor Care - FGM. Two-way ANOVA with repeated measures and Tukey's post-test (p <0.05 were used in the statistical analysis. Result Equia Fil presented the highest fluoride release in both evaluation periods, with a higher release in T1 (p <0.05. The other materials tested, including glass carbomer presented similar release in both periods (T1 and T2. Regarding surface roughness, no significant differences were observed in the interaction between the material × time factors (T1 and T2 (p=0.966. Conclusion The GICs tested presented fluoride release and recharge ability and showed no surface roughness increase by topical application of fluoride.

  12. Comparative study on the corrosion behavior of Ti-Nb and TMA alloys for dental application in various artificial solutions

    International Nuclear Information System (INIS)

    Bai, Y.J.; Wang, Y.B.; Cheng, Y.; Deng, F.; Zheng, Y.F.; Wei, S.C.

    2011-01-01

    The corrosion behavior of Ti-Nb dental alloy in artificial saliva with and without the addition of lactic acid and sodium fluoride was investigated by electrochemical techniques, with the commercial Titanium-molybdenum alloy (TMA) as a comparison. The chemical composition, microstructure and constitutional phase were characterized via energy dispersive spectrometry, optical microscope and X-ray diffraction, meanwhile the open circuit potential, electrochemical impedance spectroscopy and potentiodynamic polarization measurements were carried out to study the corrosion resistance of experimental alloys, with the corroded surface being further characterized by scanning electron microscopy and X-ray photoelectron spectroscopy. It was found that the corrosion behavior of Ti-Nb alloy was similar to those TMA alloy samples in both artificial and acidified saliva solutions, whereas statistical analysis of the electrochemical impedance spectroscopy and polarization parameters showed Ti-Nb alloy exhibited better corrosion resistance in fluoridated saliva and fluoridated acidified saliva. SEM observation indicated that TMA alloy corroded heavily than Ti-Nb alloy in fluoride containing saliva. XPS surface analysis suggested that Nb 2 O 5 played an important role in anti-corrosion from the attack of fluoride ion. Based on the above finding, Ti-Nb alloy is believed to be suitable for the usage in certain fluoride treated dental works with excellent corrosion resistance in fluoride-containing oral media.

  13. High temperature EXAFS experiments in molten actinide fluorides: The challenge of a triple containment cell for radioactive and aggressive liquids

    Science.gov (United States)

    Bessada, Catherine; Zanghi, Didier; Pauvert, Olivier; Maksoud, Louis; Gil-Martin, Ana; Sarou-Kanian, Vincent; Melin, Philippe; Brassamin, Séverine; Nezu, Atsushi; Matsuura, Haruaki

    2017-10-01

    An airtight double barrier cell with simple geometry has been developed for X-rays absorption measurements at high temperature in solid and molten actinide fluorides. The aim was both to improve the air tightness, to avoid any possible leakage and to maintain the high quality of the signal. The dimensions of the heating chamber were also constrained and minimized to be compatible with the limited space available usually on synchrotron beam lines and with a geometry suitable for absorption/diffraction measurements at high temperature. The design of the double barrier cell was also driven by the safety requirements in every experiment involving radioactive materials. The furnace itself was designed to ensure easy operating modes and disassembly, the aim being to consider the furnace as the ultimate containment. The cell has been tested with different molten fluorides up to more than 1000 °C, starting from non-radioactive LiF-ZrF4 mixtures in order to prove that the cell is absolutely airtight and that not any contamination of the environment occurs. Then it has been successfully applied to thorium fluoride- and uranium fluoride-alkali fluorides mixtures.

  14. Towards Rational Design of Functional Fluoride and Oxyfluoride Materials from First Principles

    Science.gov (United States)

    Charles, Nenian

    Complex transition metal compounds (TMCs) research has produced functional materials with a range of properties, including ferroelectricity, colossal magnetoresistance, nonlinear optical activity and high-temperature superconductivity. Conventional routes to tune properties in transition metal oxides, for example, have relied primarily on cation chemical substitution and interfacial effects in thin film heterostructures. In heteroanionic TMCs, exhibiting two chemically distinct anions coordinating the same or different cations, engineering of the anion sub-lattice for property control is a promising alternative approach. The presence of multiple anions provides additional design variables, such as anion order, that are absent in homoanionic counterparts. The more complex structural and chemical phase space of heteroanionic materials provides a unique opportunity to realize enhanced or unanticipated electronic, optical, and magnetic responses. Although there is growing interest in heteroanionic materials, and synthetic and characterization advances are occurring for these materials, the crystal-chemistry principles for realizing structural and property control are only slowing emerging. This dissertation employs anion engineering to investigate phenomena in transition metal fluorides and oxyfluorides compounds using first principles density functional theory calculations. Oxyfluorides are particularly intriguing owing their tendency to stabilize highly ordered anion sublattices as well as the potential to combine the advantageous properties of transition metal oxides and fluorides. This work 1) addresses the challenges of studying fluorides and oxyfluorides using first principles calculations; 2) evaluates the feasibility of using external stimuli, such as epitaxial strain and hydrostatic pressure, to control properties of fluorides and oxyfluorides; and 3) formulates a computational workflow based on multiple levels of theory and computation to elucidate structure

  15. Long-term Hyperglycemia Naturally Induces Dental Caries but Not Periodontal Disease in Type 1 and Type 2 Diabetic Rodents.

    Science.gov (United States)

    Nakahara, Yutaka; Ozaki, Kiyokazu; Matsuura, Tetsuro

    2017-11-01

    Periodontal disease (PD) in patients with diabetes is described as the sixth complication of diabetes. We have previously shown that diabetes increases dental caries, and carious inflammation might have a strong effect on the adjacent periodontal tissue in diabetic rodent models. However, the possibility that hyperglycemia may induce PD in diabetic animals could not be completely eliminated. The goal of this study was to confirm the presence of PD in diabetic animal models by preventing carious inflammation with fluoride administration. F344 rats injected with alloxan (type 1 diabetic model) and db/db mice (type 2 diabetic model) were given either tap water alone or tap water containing fluoride. A cariostatic effect of fluoride was evident in the diabetic animals. Meanwhile, fluoride treatment drastically attenuated periodontal inflammation in addition to preventing dental caries. Furthermore, with fluoride treatment, periodontitis was notably nonexistent in the periodontal tissue surrounding the normal molars, whereas the caries-forming process was clearly observed in the teeth that were enveloped with persistent periodontitis, suggesting that enhanced periodontal inflammation might have been derived from the dental caries in the diabetic rodents rather than from the PD. In conclusion, long-term hyperglycemia naturally induces dental caries but not PD in type 1 and type 2 diabetic rodents. © 2017 by the American Diabetes Association.

  16. Interaction of slow highly charged ions with hard dental tissue: studies of fluoride uptake and reminalization efficacy

    International Nuclear Information System (INIS)

    Daskalova, A; Kasperski, G; Rousseau, P; Domaracka, A; Lawicki, A

    2014-01-01

    TOF-SIMS mass spectroscopy data are presented on ion irradiation of hard dental tissue using a beam of 129 Xe 20+ (15 kV) ions delivered in the ARIBE facility by an ECR source. The investigation was focused on the mass distribution of the fragment ions. A comparison is made between the mass spectra from hard dental tissue treated by olaflur-(C 27 H 60 F 2 N 2 O 3 ) and untreated hard dental tissue obtained under irradiation by low-energy highly-charged ions (HCIs). We found significant differences between the mass spectra of enamel after introducing amine fluoride (olaflur) and the mass spectra of pure untreated enamel. Further, we separated out the effects caused by radiation induced in the tooth enamel from those induced in dentin, which has not been performed before. In order to conduct a further detailed analysis, it is necessary to extend the research scope to include the influence of fluorine compounds on enamel and dentin.

  17. Annotated bibliography on the effects of water containing fluorides on container-grown crops

    Energy Technology Data Exchange (ETDEWEB)

    1962-01-01

    Most of the literature on fluorine and plants relates to damage caused by atmospheric pollution, for example HF from aluminium works etc, which causes much greater damage than is possible with uptake through the roots. However a few papers do deal with uptake via the roots as follows: reviews of a general nature; uptake of fluorine and its effect on oxygen consumption; and fluoride induced chlorosis. The remainder deal with the effects of various concentrations of fluoride on container grown crops. One suggests that fluorine may be an essential trace element although its growth promoting action is not confirmed elsewhere. For the rest, the limits of fluorine tolerance are shown to be variable, related perhaps to the normal F content of the plant. No plant species however is recorded to have been damaged by concentrations of F below 10 ppM. The influence of nutrition on the appearance of symptoms of F toxicity, especially Ca nutrition but also N supply, is emphasized in two papers.

  18. Effects of dental materials on MR images

    International Nuclear Information System (INIS)

    Hinshaw, D.B. Jr.; Hoishouser, B.; Engstrom, H.

    1986-01-01

    As MR imaging of the head and neck area becomes increasingly important in evaluating pathologic conditions of the brain, mid-face, and pharynx, it is becoming apparent that artifacts due to certain dental materials can obscure the findings. Although this fact has been known for some time, a study to identify which materials produce artifacts has not been performed. The authors examined the degree of artifact production caused by various materials commonly used in dental restorations. Since not all dental materials produce artifacts during MR imaging, these materials are described also

  19. The Anticaries Efficacy of a 1.5% Arginine and Fluoride Toothpaste.

    Science.gov (United States)

    Wolff, M S; Schenkel, A B

    2018-02-01

    Dental caries remains a world-wide disease despite the global distribution of fluoride. It has become apparent that the introduction of significant levels of sugar (fermentable carbohydrate) into the diet has resulted in a change in the biofilm, encouraging acid formation. Further, there has been a shift in the microbiota in the biofilm to a flora that produces acid, and thrives and reproduces in an acidic environment. The management of caries activity under these conditions has focused on brushing to remove the biofilm with fluoride pastes, and high-dose fluoride treatments. Kleinberg, in the 1970s, identified an arginine-containing compound in saliva that several oral biofilm bacterial species metabolize to produce base. Multiple in situ and in vivo studies have been conducted, and have discussed the ability of multiple bacteria to increase the resting pH of the biofilm and even reduce the decrease in pH when the biofilm is challenged with glucose. This shift in resting pH can shift the level of caries formation by the biofilm. Here, we present 8 clinical studies, with different clinical designs, measuring different clinical outcomes, for a diverse, world-wide population. Each of these studies demonstrates reductions in caries formation beyond that seen with fluoride alone and several demonstrate the reversal of early caries lesions. Significant clinical research has been shown that 1.5% arginine combined with fluoride toothpaste has superior anti-caries efficacy to toothpaste containing fluoride alone.

  20. Potential fluoride toxicity from oral medicaments: A review

    Directory of Open Access Journals (Sweden)

    Rizwan Ullah

    2017-08-01

    Full Text Available The beneficial effects of fluoride on human oral health are well studied. There are numerous studies demonstrating that a small amount of fluoride delivered to the oral cavity decreases the prevalence of dental decay and results in stronger teeth and bones. However, ingestion of fluoride more than the recommended limit leads to toxicity and adverse effects. In order to update our understanding of fluoride and its potential toxicity, we have described the mechanisms of fluoride metabolism, toxic effects, and management of fluoride toxicity. The main aim of this review is to highlight the potential adverse effects of fluoride overdose and poorly understood toxicity. In addition, the related clinical significance of fluoride overdose and toxicity has been discussed.

  1. Preparation of Bioactive Titanium Surfaces via Fluoride and Fibronectin Retention

    Directory of Open Access Journals (Sweden)

    Carlos Nelson Elias

    2012-01-01

    Full Text Available Statement of Problem. The chemical or topographic modification of the dental implant surface can affect bone healing, promote accelerated osteogenesis, and increase bone-implant contact and bonding strength. Objective. In this work, the effects of dental implant surface treatment and fibronectin adsorption on the adhesion of osteoblasts were analyzed. Materials and Methods. Two titanium dental implants (Porous-acid etching and PorousNano-acid etching followed by fluoride ion modification were characterized by high-resolution scanning electron microscopy, atomic force microscopy, and X-ray diffraction before and after the incorporation of human plasma fibronectin (FN. The objective was to investigate the biofunctionalization of these surfaces and examine their effects on the interaction with osteoblastic cells. Results. The evaluation techniques used showed that the Porous and PorousNano implants have similar microstructural characteristics. Spectrophotometry demonstrated similar levels of fibronectin adsorption on both surfaces (80%. The association indexes of osteoblastic cells in FN-treated samples were significantly higher than those in samples without FN. The radioactivity values associated with the same samples, expressed as counts per minute (cpm, suggested that FN incorporation is an important determinant of the in vitro cytocompatibility of the surfaces. Conclusion. The preparation of bioactive titanium surfaces via fluoride and FN retention proved to be a useful treatment to optimize and to accelerate the osseointegration process for dental implants.

  2. Effect of Fluoride-Releasing Adhesive Systems on the Mechanical Properties of Eroded Dentin.

    Science.gov (United States)

    Guedes, Ana Paula Albuquerque; Moda, Mariana Dias; Suzuki, Thaís Yumi Umeda; Godas, André Gustavo de Lima; Sundfeld, Renato Herman; Briso, André Luiz Fraga; Santos, Paulo Henrique dos

    2016-01-01

    The aim of the study was to evaluate the effect of erosive pH cycling with solutions that simulate dental erosion on Martens hardness (HMV) and elastic modulus (Eit) of dentin restored with fluoride-releasing adhesive systems. Twenty-seven bovine dentin slabs were restored with three adhesive systems: Adper Single Bond 2 total-etch adhesive system, One Up Bond F and Clearfil SE Protect fluoride-containing self-etching adhesive systems. The restorations were made with Filtek Z250. The HMV and Eit values at distances of 10, 30, 50 and 70 µm from the interface were evaluated using a dynamic ultra microhardness tester before and after immersion in deionized water, citric acid and hydrochloric acid (n=9). Data were submitted to repeated-measures ANOVA and Fisher's PLSD tests (=0.05). After erosive cycling, HMV values of dentin decreased in all groups. For dentin restored with Adper Single Bond 2, the lowest values were found closer to the hybrid layer, while for One Up Bond F and Clearfil SE Protect, the values remained unaltered at all distances. For dentin restored with fluoride-releasing adhesive systems, a decrease in Eit was found, but after 30 µm this difference was not significant. The acid substances were able to alter HMV and Eit of the underlying dentin. For fluoride-releasing adhesives, the greater the distance from bonded interface, the lower the Eit values. The fluoride in One Up Bond F and Clearfil SE Protect was able to protect the underlying dentin closer to the materials. In this way, the fluoride from adhesive systems could have some positive effect in the early stages of erosive lesions.

  3. Health effects of fluoride pollution caused by coal burning

    Energy Technology Data Exchange (ETDEWEB)

    Ando, M.; Tadano, M.; Yamamoto, S.; Tamura, K.; Chen, X. [Regional Environment Division, National Institute for Environmental Studies, Tsukuba, 305-0083 Ibaraki (Japan); Asanuma, S. [Japan Institute of Rural Medicine, Usuda, Nagano (Japan); Watanabe, T. [Saku Central Hospital, Usuda, Nagano (Japan); Kondo, T. [Matsumoto Dental College, Shiojiri, Nagano (Japan); Sakurai, S. [Otsuma Women' s University, Tama, Tokyo (Japan); Ji, R.; Liang, C.; Cao, S. [Institute of Environmental Health and Engineering, Beijing (China); Hong, Z. [Shanxi Maternity and Children' s Hospital, Taiyuan (China)

    2001-04-23

    Recently a huge amount of fluoride in coal has been released into indoor environments by the combustion of coal and fluoride pollution seems to be increasing in some rural areas in China. Combustion of coal and coal bricks is the primary source of gaseous and aerosol fluoride and these forms of fluoride can easily enter exposed food products and the human respiratory tract. Major human fluoride exposure was caused by consumption of fluoride contaminated food, such as corn, chilies and potatoes. For each diagnostic syndrome of dental fluorosis, a log-normal distribution was observed on the logarithm of urinary fluoride concentration in students in China. Urinary fluoride content was found to be a primary health indicator of the prevalence of dental fluorosis in the community. In the fluorosis areas, osteosclerosis in skeletal fluorosis patients was observed with a high prevalence. A biochemical marker of bone resorption, urinary deoxypyridinoline content was much higher in residents in China than in residents in Japan. It was suggested that bone resorption was stimulated to a greater extent in residents in China and fluoride may stimulate both bone resorption and bone formation. Renal function especially glomerular filtration rate was very sensitive to fluoride exposure. Inorganic phosphate concentrations in urine were significantly lower in the residents in fluorosis areas in China than in non-fluorosis area in China and Japan. Since airborne fluoride from the combustion of coal pollutes extensively both the living environment and food, it is necessary to reduce fluoride pollution caused by coal burning.

  4. Mechanisms of action of fluoride for caries control

    NARCIS (Netherlands)

    Buzalaf, M.A.R.; Pessan, J.P.; Honório, H.M.; ten Cate, J.M.; Buzalaf, M.A.R.

    2011-01-01

    Fluoride was introduced into dentistry over 70 years ago, and it is now recognized as the main factor responsible for the dramatic decline in caries prevalence that has been observed worldwide. However, excessive fluoride intake during the period of tooth development can cause dental fluorosis. In

  5. Advanced inorganic fluorides. Proceedings of the Second International Siberian workshop INTERSIBFLUORINE-2006

    International Nuclear Information System (INIS)

    Volkov, V.V.; Mit'kin, V.N.; Bujnovskij, A.S.; Sofronov, V.L.

    2006-01-01

    Proceedings of the Second International Siberian workshop ISIF-2006 on modern inorganic fluorides contain full author's texts of 82 plenary reports and posters on the main trends in chemistry and technology of inorganic fluorides and their various applications. The following new trends are reflected in the ISIF-2006 Proceedings versus the ISIF-2003 ones: production and use of of nano-sized systems and materials based on fluoride phases and fluorinating systems; chemistry of fluorofullerenes, fluorides of graphite and carbon materials; development of research and technical principles of economically viable process of depleted uranium hexafluoride conversion; vitrifying systems based on metal fluorides possessing valuable functional optical properties; mechanochemical processes and phenomena in chemistry of inorganic fluorides [ru

  6. The staining effect of different mouthwashes containing nanoparticles on dental enamel.

    OpenAIRE

    Eslami, Neda; Ahrari, Farzaneh; Rajabi, Omid; Zamani, Roya

    2015-01-01

    Background This study aimed to evaluate the effects of several mouthwashes containing nanoparticles on discoloration of dental enamel, and compare the results with that of 0.2% chlorhexidine (CHX). Material and Methods Sixty intact premolars were randomly assigned to six groups. A spectrophotometer was used to measure the color of the teeth (T1) according to the CIELAB system. The specimens in groups 1 to 4 were then immersed in colloidal solutions containing nanoTiO2 (Group 1), nanoZnO (Grou...

  7. Spatial distribution mapping of drinking water fluoride levels in Karnataka, India: fluoride-related health effects.

    Science.gov (United States)

    Chowdhury, Chitta R; Shahnawaz, Khijmatgar; Kumari, Divya; Chowdhury, Avidyuti; Bedi, Raman; Lynch, Edward; Harding, Stewart; Grootveld, Martin

    2016-11-01

    (1) To estimate the concentrations of fluoride in drinking water throughout different zones and districts of the state of Karnataka. (2) To investigate the variation of fluoride concentration in drinking water from different sources, and its relationships to daily temperature and rainfall status in the regional districts. (3) To develop an updated fluoride concentration intensity map of the state of Karnataka, and to evaluate these data in the context of fluoride-related health effects such as fluorosis and their prevalence. Aqueous standard solutions of 10, 100 and 1,000 ppm fluoride (F - ) were prepared with analytical grade Na + /F - and a buffer; TISAB II was incorporated in both calibration standard and analysis solutions in order to remove the potentially interfering effects of trace metal ions. This analysis was performed using an ion-selective electrode (ISE), and mean determination readings for n = 5 samples collected at each Karnataka water source were recorded. The F - concentration in drinking water in Karnataka state was found to vary substantially, with the highest mean values recorded being in the north-eastern zone (1.61 ppm), and the lowest in the south-western one (only 0.41 ppm). Analysis of variance (ANOVA) demonstrated that there were very highly significant 'between-zone' and 'between-districts-within-zones' sources of variation (p water source F - levels within this state. The southern part of Karnataka has low levels of F - in its drinking water, and may require fluoridation treatment in order to mitigate for dental caries and further ailments related to fluoride deficiency. However, districts within the north-eastern region have contrastingly high levels of fluoride, an observation which has been linked to dental and skeletal fluorosis. This highlights a major requirement for interventional actions in order to ensure maintenance of the recommended range of fluoride concentrations (0.8-1.5 ppm) in Karnataka's drinking water

  8. In vitro effect of calcium-containing prescription-strength fluoride toothpastes on bovine enamel erosion under hyposalivation-simulating conditions.

    Science.gov (United States)

    Scaramucci, Taís; Borges, Alessandra B; Lippert, Frank; Zero, Domenick T; Hara, Anderson T

    2015-02-01

    To evaluate the ability of calcium-containing prescription-strength fluoride (F) toothpastes in preventing enamel erosion under low salivary flow simulating conditions. Enamel and dentin bovine specimens were assigned to the following groups: A - placebo; B - 1,100 ppm F/NaF (Aquafresh Advanced); C - 5,000 ppm F/NaF (Prevident 5000 Booster); D - 5000 ppm F/NaF+calcium sodium phosphosilicate (Topex Renew); and E - 5,000 ppm F/NaF+tri-calcium phosphate (Clinpro 5000). Specimens were positioned in custom-made devices, creating a sealed chamber on the surface, connected to peristaltic pumps. Citric acid was injected into the chamber for 2 minutes, followed by artificial saliva (0.05 ml/minute), for 60 minutes, 4x/day, for 3 days. Aquafresh was also tested under normal salivary flow (0.5 ml/minute), as reference (Group F). Specimens were exposed to the toothpastes for 2 minutes, 2x/day. After cycling, surface loss (SL) and concentration of loosely- and firmly-bound F were determined. Data were analyzed by ANOVA. Results: Group A (placebo) presented highest surface loss (SL), while Group F had the lowest, for both substrates. For enamel, none of the dentifrices differed from Group B or among each other. For dentin, none of the dentifrices differed from Group B, but Group E showed greater protection than Group C. Group E presented the highest F concentrations for both substrates, only matched by Group D for firmly-bound fluoride on enamel. All fluoridated dentifrices tested reduced SL, with no additional benefit from higher F concentrations. Some formulations, especially Clinpro 5000, increased F availability on the dental substrates, but no further erosion protection was observed.

  9. Hexamethyldisilazane Removal with Mesoporous Materials Prepared from Calcium Fluoride Sludge.

    Science.gov (United States)

    Kao, Ching-Yang; Lin, Min-Fa; Nguyen, Nhat-Thien; Tsai, Hsiao-Hsin; Chang, Luh-Maan; Chen, Po-Han; Chang, Chang-Tang

    2018-05-01

    A large amount of calcium fluoride sludge is generated by the semiconductor industry every year. It also requires a high amount of fuel consumption using rotor concentrators and thermal oxidizers to treat VOCs. The mesoporous adsorbent prepared by calcium fluoride sludge was used for VOCs treatment. The semiconductor industry employs HMDS to promote the adhesion of photo-resistant material to oxide(s) due to the formation of silicon dioxide, which blocks porous adsorbents. The adsorption of HMDS (Hexamethyldisiloxane) was tested with mesoporous silica materials synthesized from calcium fluoride (CF-MCM). The resulting samples were characterized by XRD, XRF, FTIR, N2-adsorption-desorption techniques. The prepared samples possessed high specific surface area, large pore volume and large pore diameter. The crystal patterns of CF-MCM were similar with Mobil composite matter (MCM-41) from TEM image. The adsorption capacity of HMDS with CF-MCM was 40 and 80 mg g-1, respectively, under 100 and 500 ppm HMDS. The effects of operation parameters, such as contact time and mixture concentration, on the performance of CF-MCM were also discussed in this study.

  10. Adverse effects of fluoride towards thyroid hormone metabolism

    Directory of Open Access Journals (Sweden)

    Enggar Abdullah Idris MZ

    2008-03-01

    Full Text Available An easily ionized fluoride compound like Sodium Fluoride (NaF has been used thus far as a dental caries prevention substance. However, fluoride ions also have a negative effect because it is very toxic. Several types of research on the effect of fluoride on guinea pigs and human beings indicate the presence synthesis obstruction of T3 and T4 that causes declined production, known as hypothyroidism. Hypothyroidism condition may obstruct tissue growth process and metabolism so as to impact various body organ systems. Preventive efforts against hypothyroidism caused by fluoride include avoiding diffusible fluoride compound intake, like NaF, in a long run systemic use, whereas efforts to overcome fluoride intoxication include consuming food that is rich in calcium, vitamin D, and antioxidant.

  11. The association between fluoride in drinking water and dental caries in Danish children. Linking data from health registers, environmental registers and administrative registers

    DEFF Research Database (Denmark)

    Kirkeskov, Lilli; Kristiansen, Eva; Bøggild, Henrik

    2010-01-01

    with data on dental caries from the Danish National Board of Health database on child dental health for 5-year-old children born in 1989 and 1999, and for 15-year-old children born in 1979 and 1989. The number of children included in the cohorts varied between 41.000 and 48.000. Logistic regression was used...... if analysis was limited to children residing in the same place during the entire study period. Conclusions: The study confirmed previous findings of an inverse relation between fluoride concentration in the drinking water and dental caries in children. This correlation was found in spite of the extensive use...

  12. The prevalence of fluorosis in children is associated with naturally occurring water fluoride concentration in Mexico.

    Science.gov (United States)

    Mariño, Rodrigo

    2013-09-01

    Fluorosis and dental caries in Mexican schoolchildren residing in areas with different water fluoride concentrations and receiving fluoridated salt. Garcia-Perez A, Irigoyen-Carnacho ME, Borges-Yanez A. Caries Res 2013;47(4):299-308. Rodrigo Mariño Is there an association between the presence of dental fluorosis and fluoride concentration in drinking water? and Is there an association between the severity of fluorosis and dental caries experience in schoolchildren residing in two rural towns in Mexico (with water fluoride concentrations of 0.70 and 1.50 ppm) that also receive fluoridated salt? Government: National Council of Science and Technology (Consejo Nacional de Ciencia y Tecnologia, CONACYT) Other: Autonomous University, Xochimilco (Universidad Autonoma Metropolitana, UAM-X) TYPE OF STUDY/DESIGN: Cross-sectional Level 3: Other evidence Not applicable. Copyright © 2013 Elsevier Inc. All rights reserved.

  13. Fluoride kinetics in saliva after the use of a fluoride-containing chewing gum Cinética de flúor na saliva após o uso de uma goma de mascar fluoretada

    Directory of Open Access Journals (Sweden)

    Maria Francisca Thereza Borro Bijella

    2005-12-01

    Full Text Available There is a relationship between the use of fluoride, the reduction of dental caries and the increase of dental fluorosis. The purpose of this study was to analyze the fluoride kinetics in saliva after using the HappydentTM chewing gum, which contains 3.38 mg of fluoride as monofluorophosphate. Fifteen 7-9-year-old volunteers were instructed to chew the gum TridentTM (control and HappydentTM on different days. Total saliva was collected for 3 minutes, at 0, 3, 6, 9, 15, 30 and 45 minutes after starting chewing. Salivary fluoride was analyzed with a fluoride-specific electrode (Orion 96-09 after acid hydrolysis. The data were analyzed by two-way analysis of variance and by Tukey’s post hoc test (p Há uma relação entre o uso de fluoretos, a redução na cárie e o aumento da fluorose dentária. O objetivo deste estudo foi analisar a cinética do flúor na saliva após o uso da goma de mascar Happydent®, que contém 3,38 mg de flúor como monofluorfosfato. A saliva foi coletada de 15 voluntários entre 7 e 9 anos de idade, durante 3 minutos nos intervalos de 0, 3, 6, 9, 15, 30 e 45 minutos. Inicialmente, a coleta foi realizada com o Trident® (controle e, após 24 h, a coleta foi repetida com a goma de mascar Happydent®. O flúor foi analisado com um eletrodo íon-específico (Orion 96-09 após a realização da hidrólise ácida. Os dados foram analisados através da análise de variância a dois critérios e pelo teste de Tukey (p < 0,05. A quantidade média ± dp (mg de flúor liberado na saliva foi 0,276 ± 0,126 e 0,024 ± 0,014 para o Happydent® e o Trident®, respectivamente. A quantidade de flúor nas amostras de saliva após o uso do Happydent® foi significativamente maior do que após o uso do Trident® em todos os tempos experimentais, com exceção dos períodos de 30 e 45 minutos. A alta quantidade de flúor na saliva após o uso do Happydent® poderia ser eficiente na prevenção da cárie dentária, o que deveria ser avaliado

  14. DENTAL MATERIAL BIOCOMPATIBILITY: A CROSS-SECTIONAL STUDY

    Directory of Open Access Journals (Sweden)

    Carmen SAVIN

    2017-06-01

    Full Text Available The aim of this study is to assess the knowledge of the students in the Faculty of Dental Medicine of Iasi on the biocompatibility of the dental materials used in current practice. To this end, we elaborated our own questionnaire, including 10 questions to which 92 students from the last 2 years of study answered. The questionnaire cotains assertions on the potential toxic reactions of the most frequently used dental materials. The students answered correctly to the questions related to the biocompatibility of certain dental materials, such as glass-ionomer cement and calcium hydroxide, and they recognized that allergic reactions determined by acrylic resins may occur. We also noticed the lack of knowledge referring to the irreversible modifications produced by the tooth whitening substances on the enamel and dentin, as well as to the side effects produced by dental amalgam.

  15. Advances in dental materials.

    Science.gov (United States)

    Fleming, Garry J P

    2014-05-01

    The dental market is replete with new resorative materials marketed on the basis of novel technological advances in materials chemistry, bonding capability or reduced operator time and/or technique sensitivity. This paper aims to consider advances in current materials, with an emphasis on their role in supporting contemporary clinical practice.

  16. Penetration of fluoride-containing self-gelling liquids into human molar occlusal fissures in vitro.

    Science.gov (United States)

    Bottenberg, P; Slop, D; Coomans, D

    1989-01-01

    In this in vitro study the ability and speed of self-gelling liquid compositions to penetrate into fissures were evaluated. Two formulations containing either tetraethylsilicate, ammonium fluoride, and sodium lauryl sulfate or tetraethylsilicate, sodium fluoride, and cetylpyridinium chloride at different concentrations were used. It is shown that fissure penetration occurs when a certain minimum content of surface-active agent is present. Fissure penetration is achieved within 3-4 s, according to the fissure morphology.

  17. Reduction in fluoride-induced genotoxicity in mouse bone marrow cells after substituting high fluoride-containing water with safe drinking water.

    Science.gov (United States)

    Podder, Santosh; Chattopadhyay, Ansuman; Bhattacharya, Shelley

    2011-10-01

    Treatment of mice with 15 mg l(-1) sodium fluoride (NaF) for 30 days increased the number of cell death, chromosomal aberrations (CAs) and 'cells with chromatid breaks' (aberrant cells) compared with control. The present study was intended to determine whether the fluoride (F)-induced genotoxicity could be reduced by substituting high F-containing water after 30 days with safe drinking water, containing 0.1 mg F ions l(-1). A significant fall in percentage of CAs and aberrant cells after withdrawal of F-treatment following 30 days of safe water treatment in mice was observed which was highest after 90 days, although their levels still remained significantly high compared with the control group. This observation suggests that F-induced genotoxicity could be reduced by substituting high F-containing water with safe drinking water. Further study is warranted with different doses and extended treatment of safe water to determine whether the induced damages could be completely reduced or not. Copyright © 2011 John Wiley & Sons, Ltd.

  18. Investigation of contact allergy to dental materials by patch testing

    Directory of Open Access Journals (Sweden)

    Reena Rai

    2014-01-01

    Full Text Available Background: Dental products are widely used by patients and dental personnel alike and may cause problems for both. Dental materials could cause contact allergy with varying manifestations such as burning, pain, stomatitis, cheilitis, ulcers, lichenoid reactions localized to the oral mucosa in patients, and hand dermatitis in dental personnel. Patch testing with the dental series comprising commonly used materials can be used to detect contact allergies to dental materials. Aim: This study aimed to identify contact allergy among patients who have oral mucosal lesions after dental treatment and among dental personnel who came in contact with these materials. Materials and Methods: Twenty patients who had undergone dental procedures with symptoms of oral lichen planus, oral stomatitis, burning mouth, and recurrent aphthosis, were included in the study. Dental personnel with history of hand dermatitis were also included in the study. Patch testing was performed using Chemotechnique Dental Series and results interpreted as recommended by the International Contact Dermatitis Research Group (ICDRG. Results: Out of 13 patients who had undergone dental treatment/with oral symptoms, six patients with stomatitis, lichenoid lesions, and oral ulcers showed positive patch tests to a variety of dental materials, seven patients with ulcers had negative patch tests, seven dental personnel with hand dermatitis showed multiple allergies to various dental materials, and most had multiple positivities. Conclusion: The patch test is a useful, simple, noninvasive method to detect contact allergies among patients and among dental personnel dealing with these products. Long term studies are necessary to establish the relevance of these positive patch tests by eliminating the allergic substances, identifying clinical improvement, and substituting with nonallergenic materials.

  19. Influência da aplicação de flúor sobre a rugosidade superficial do ionômero de vidro Vitremer e adesão microbiana a este material Influence of the application of fluoride on the superficial roughness of Vitremer glass ionomer cement and microbial adhesion to this material

    Directory of Open Access Journals (Sweden)

    Denise PEDRINI

    2001-03-01

    Full Text Available Os cimentos ionoméricos representam importante opção de material restaurador em Odontologia e sua adesão à estrutura dental, diminuindo a infiltração marginal, somada à liberação de flúor, inibindo o metabolismo de microrganismos acidogênicos e favorecendo a remineralização dental, podem diminuir a ocorrência de cárie secundária. A aplicação tópica de géis acidulados ou neutros contendo flúor tem sido largamente utilizada em Odontologia. No entanto, este procedimento pode afetar a integridade dos materiais restauradores, aumentando sua rugosidade e a retenção de placa bacteriana. Dessa forma, o presente estudo avaliou o período de tempo no qual o cimento ionomérico Vitremer mantém sua capacidade inibitória sobre Streptococcus mutans ATCC 25175 e a adesão dos mesmos sobre a superfície do material, bem como a influência da aplicação tópica de flúor acidulado e neutro sobre esses parâmetros microbiológicos e as características superficiais daquele material. Verificou-se que a atividade antimicrobiana do cimento ionomérico Vitremer se mantém por aproximadamente quatro dias e não é recuperada com o uso de flúor gel acidulado ou neutro. Observou-se, também, que Streptococcus mutans ATCC 25175 adere ao material restaurador testado sendo que a aplicação tópica de flúor não influenciou esta adesão. As características superficiais desses materiais não se alteraram com a aplicação dos géis.Glass ionomer cements are important options in restorative and preventive dentistry due to their adhesion to the tooth surface and to fluoride release, which can decrease the risk of recurrent caries. The topical use of acidulated and neutral fluoride gels has been frequent in dentistry. However, this procedure can adversely affect the surface of restorative materials, increasing their roughness and the retention of dental plaque. Thus, this study evaluated the period in which Vitremer glass ionomer cement maintains

  20. Fluoride supplementation (with tablets, drops, lozenges or chewing gum) in pregnant women for preventing dental caries in the primary teeth of their children.

    Science.gov (United States)

    Takahashi, Rena; Ota, Erika; Hoshi, Keika; Naito, Toru; Toyoshima, Yoshihiro; Yuasa, Hidemichi; Mori, Rintaro; Nango, Eishu

    2017-10-23

    Dental caries (tooth decay) is one of the most common chronic childhood diseases. Caries prevalence in most industrialised countries has declined among children over the past few decades. The probable reasons for the decline are the widespread use of fluoride toothpaste, followed by artificial water fluoridation, oral health education and a slight decrease in sugar consumption overall. However, in regions without water fluoridation, fluoride supplementation for pregnant women may be an effective way to increase fluoride intake during pregnancy. If fluoride supplements taken by pregnant women improve neonatal outcomes, pregnant women with no access to a fluoridated drinking water supply can obtain the benefits of systemic fluoridation. To evaluate the effects of women taking fluoride supplements (tablets, drops, lozenges or chewing gum) compared with no fluoride supplementation during pregnancy to prevent caries in the primary teeth of their children. Cochrane Oral Health's Information Specialist searched the following databases: Cochrane Oral Health's Trials Register (to 25 January 2017); the Cochrane Central Register of Controlled Trials (CENTRAL; 2016, Issue 11) in the Cochrane Library (searched 25 January 2017); MEDLINE Ovid (1946 to 25 January 2017); Embase Ovid (1980 to 25 January 2017); LILACS BIREME Virtual Health Library (Latin American and Caribbean Health Science Information database; 1982 to 25 January 2017); and CINAHL EBSCO (Cumulative Index to Nursing and Allied Health Literature; 1937 to 25 January 2017). We searched the US National Institutes of Health Ongoing Trials Register (ClinicalTrials.gov) and the World Health Organization International Clinical Trials Registry Platform for ongoing trials to 25 January 2017. No restrictions were placed on the language or date of publication when searching the electronic databases. Randomised controlled trials (RCTs) of fluoride supplements (tablets, drops, lozenges or chewing gum) administered to women during

  1. Removal of fluoride from water using aluminium containing compounds

    Institute of Scientific and Technical Information of China (English)

    M. Karthikeyan; K. P. Elango

    2009-01-01

    Batch adsorption studies were undertaken to assess the suitability of aluminium titanate (AT) and bismuth aluminate (BA) to remove fluoride ions from water.The effect of pH,dose of adsorbent,contact time,initial concentration,co-ions and temperature on fluoride removal efficiency were studied.The amounts of fluoride ions adsorbed,at 30℃ from 4 mg/L of fluoride ion solution,by AT and BA are 0.85 and 1.55 mg/g,respectively.The experimental data fitted well to the Freundlich and Langmuir isotherms.Thermodynamic parameters such as △H~0,△S~0 and △G~0 indicated that the removal of fluoride ions by AT is exothermic and non-spontaneous while that by BA is endothermic and spontaneous.Furrier transform infrared (FT-IR) analysis and X-ray diffraction (XRD) patterns of the adsorbent before and after adsorption indicated that fluoride ions are chemisorbed by these adsorbents.

  2. Caries prevalence and fluoride use in low SES children in Clermont-Ferrand (France).

    Science.gov (United States)

    Tubert-Jeannin, S; Riordan, P J; Manevy, R; Lecuyer, M M; Pegon-Machat, E

    2009-03-01

    To evaluate the association between dental caries experience and preventive behaviours of children residing in a deprived area in Clermont-Ferrand (France). All 4-5 yr-olds attending nine schools in deprived areas of the city were invited to participate and 81% (n=282) consented and were examined. Dental caries was recorded at the dentine threshold. Parents completed a questionnaire concerning family demographics and the child's use of fluoride. Non-parametric tests and logistic regression assessed the relative importance of SES and fluoride variables on dental status (dt>1). Fifty four (19%) of the examined children were living in families with an immigrant background, 33% were fully covered by the national health insurance programme for deprived families. Caries experience was high; mean dft was 1.94 (3.31) and 30% of the children had >1 carious teeth. Thirty percent of the families reported using fluoridated salt. Tooth brushing once daily was reported for 39% and twice daily for 26%. Parents declared supervising tooth brushing for 60%. Two thirds of the children, according to their parents, used fluoride supplement between birth and two years. Supervised tooth brushing was significantly correlated with lower mean dt scores. Systemic fluoride use was poorly related to dental caries Immigrant background, family size, type of health insurance and mother's unemployment were significantly correlated with caries prevalence. In multivariate analysis, immigrant status, supervised tooth brushing and parental knowledge about fluoride in toothpastes were significant caries predictors. The majority of low SES children did not practice effective caries prevention; few reported twice daily brushing with fluoride toothpaste. Caries experience was very high and much was untreated. Immigrant status, supervised tooth brushing and parental knowledge about fluoride in toothpastes were significant caries predictors.

  3. Fluoride removal from double four-membered ring (D4R) units in As-synthesized Ge-containing zeolites

    KAUST Repository

    Liu, Xiaolong; Ravon, Ugo; Tuel, Alain

    2011-01-01

    Fluoride anions can be removed from the framework of as-prepared Ge-containing zeolites ITQ-13 and ITQ-17 without modification of the crystallinity and crystal habit. By contrast to all-silica ITQ-13 for which fluoride could not get out from D4R

  4. Physiologic Conditions Affect Toxicity of Ingested Industrial Fluoride

    Directory of Open Access Journals (Sweden)

    Richard Sauerheber

    2013-01-01

    Full Text Available The effects of calcium ion and broad pH ranges on free fluoride ion aqueous concentrations were measured directly and computed theoretically. Solubility calculations indicate that blood fluoride concentrations that occur in lethal poisonings would decrease calcium below prevailing levels. Acute lethal poisoning and also many of the chronic effects of fluoride involve alterations in the chemical activity of calcium by the fluoride ion. Natural calcium fluoride with low solubility and toxicity from ingestion is distinct from fully soluble toxic industrial fluorides. The toxicity of fluoride is determined by environmental conditions and the positive cations present. At a pH typical of gastric juice, fluoride is largely protonated as hydrofluoric acid HF. Industrial fluoride ingested from treated water enters saliva at levels too low to affect dental caries. Blood levels during lifelong consumption can harm heart, bone, brain, and even developing teeth enamel. The widespread policy known as water fluoridation is discussed in light of these findings.

  5. Physiologic conditions affect toxicity of ingested industrial fluoride.

    Science.gov (United States)

    Sauerheber, Richard

    2013-01-01

    The effects of calcium ion and broad pH ranges on free fluoride ion aqueous concentrations were measured directly and computed theoretically. Solubility calculations indicate that blood fluoride concentrations that occur in lethal poisonings would decrease calcium below prevailing levels. Acute lethal poisoning and also many of the chronic effects of fluoride involve alterations in the chemical activity of calcium by the fluoride ion. Natural calcium fluoride with low solubility and toxicity from ingestion is distinct from fully soluble toxic industrial fluorides. The toxicity of fluoride is determined by environmental conditions and the positive cations present. At a pH typical of gastric juice, fluoride is largely protonated as hydrofluoric acid HF. Industrial fluoride ingested from treated water enters saliva at levels too low to affect dental caries. Blood levels during lifelong consumption can harm heart, bone, brain, and even developing teeth enamel. The widespread policy known as water fluoridation is discussed in light of these findings.

  6. A model to determine the economic viability of water fluoridation.

    Science.gov (United States)

    Kroon, Jeroen; van Wyk, Philippus Johannes

    2012-01-01

    In view of concerns expressed by South African local authorities the aim of this study was to develop a model to determine whether water fluoridation is economically viable to reduce dental caries in South Africa. Microsoft Excel software was used to develop a model to determine economic viability of water fluoridation for 17 water providers from all nine South African provinces. Input variables for this model relate to chemical cost, labor cost, maintenance cost of infrastructure, opportunity cost, and capital depreciation. The following output variables were calculated to evaluate the cost of water fluoridation: per capita cost per year, cost-effectiveness and cost-benefit. In this model it is assumed that the introduction of community water fluoridation can reduce caries prevalence by an additional 15 percent and that the savings in cost of treatment will be equal to the average fee for a two surface restoration. Water providers included in the study serve 53.5 percent of the total population of South Africa. For all providers combined chemical cost contributes 64.5 percent to the total cost, per capita cost per year was $0.36, cost-effectiveness was calculated as $11.41 and cost-benefit of the implementation of water fluoridation was 0.34. This model confirmed that water fluoridation is an economically viable option to prevent dental caries in South African communities, as well as conclusions over the last 10 years that water fluoridation leads to significant cost savings and remains a cost-effective measure for reducing dental caries, even when the caries-preventive effectiveness is modest. © 2012 American Association of Public Health Dentistry.

  7. Structural changes in fluorosed dental enamel of red deer (Cervus elaphus L.) from a region with severe environmental pollution by fluorides

    International Nuclear Information System (INIS)

    Kierdorf, U.; Kierdorf, H.; Sedlacek, F.; Fejerskov, O.

    1996-01-01

    A macroscopic, microradiographic and scanning electron microscope study was performed on the structure of fluorosed dental enamel in red deer from a fluoride polluted region (North Bohemia, Czech Republic). As was revealed by analysis of mandibular bone fluoride content, the rate of skeletal fluoride accumulation in the fluorotic deer was about 6 times that in controls taken from a region not exposed to excessive fluoride deposition. In all fluorosed mandibles, the 1st molar was consistently less fluorotic than the other permanent teeth. This was related to the fact that crown formation in the M1 takes place prenatally and during the lactation period. Fluorosed teeth exhibited opaque and posteruptively stained enamel, reduction or loss of enamel ridges, moderately to grossly increased wear and, in more severe cases, also enamel surface lesions of partly posteruptive, partly developmental origin. Microradiographically, fluorosed enamel was characterised by subsurface hypomineralisation, interpreted as a result of fluoride interference with the process of enamel maturation. In addition, an accentuation of the incremental pattern due to the occurrence of alternating bands with highly varying mineral content was observed in severely fluorosed teeth, denoting fluoride disturbance during the secretory stage of amelogenesis. A corresponding enhancement of the incremental pattern was also seen in the dentine. The enamel along the more pronounced hypoplasias consisted of stacked, thin layers of crystals arranged in parallel, indicating that the ameloblasts in these locations had lost the distal (prism-forming) portions of their Tomes processes. The findings of the present study indicate that red deer are highly sensitive bioindicators of environmental pollution by fluorides

  8. Mg-containing hydroxyapatite coatings on Ti-6Al-4V alloy for dental materials

    Science.gov (United States)

    Yu, Ji-Min; Choe, Han-Cheol

    2018-02-01

    In this study, Mg-containing hydroxyapatite coatings on Ti-6A1-4 V alloy for dental materials were researched using various experimental instruments. Plasma electrolytic oxidation (PEO) was performed in electrolytes containing Mg (symbols of specimens: CaP, 5M%, 10M%, and 20M%) at 280 V for 3 min. The electrolyte used for PEO was produced by mixing Ca(CH3COO)2·H2O, C3H7NaCaO6P, and MgCl2·6H2O. The phases and composition of the oxide films were evaluated by X-ray diffraction and field-emission scanning electron microscopy with energy dispersive X-ray spectrometry. The irregularity of the surface, pore size, and number of pores decreased as the Mg concentration increased. The ratio of the areas occupied and not occupied by pores decreased as the Mg concentration increased, with the numbers of both large and small pores decreasing with increasing Mg concentration. The number of particles on the internal surfaces of pores was increased as the Mg content increased. Mg content of all samples containing Mg ions showed higher in the pore outside than that of pore inside, whereas the Ca content was higher inside the pores. The P content of samples with the addition of Mg ions showed higher values inside the pores than outside. The Ca/P and [Mg + Ca]/P molar ratios in the PEO films decreased with Mg content. The crystallite size of anatase was increased with increasing Mg concentration in the solution.

  9. Comparison of Antibacterial Effect of Fluoride and Chlorhexidine on Two Cariogenic Bacteria: An in Vitro Study

    Directory of Open Access Journals (Sweden)

    Poureslami HR

    2014-09-01

    Full Text Available Statement of problem: Dental plaque is the main source for dental caries and there is no proper vaccine that can affect dental plaques. Objectives: Daily use of an efficient anti-plaque product can be very beneficial in plaque control and, thus, prevention of caries. This study aims to evaluate the antibacterial effects of four products of Chlorhexidine and Fluoride on two types of cariogenic bacteria. Materials and Methods: In this in vitro study, the antibacterial effect of Chlorhexidine and Fluoride (gel and solution against Streptococci Sanguis and Sobrinus was evaluated. Chlorhexidine gluconate 1% gel (Corosodyl, France, Chlorhexidine gluconate 2% solution (Consepsis, Ultradent, US, Sodium fluoride 0.2% solution (Oral-B, US and Acidulated Phosphate Fluoride 1.23% gel ( Denti-Care, Canada were used. The disc diffusion method was used for testing bacterial sensitivity. The data were analyzed using paired t-test and Chi-square test. Results: In comparison with the negative control, each of the four gels and solutions showed antibacterial effects but the effects were not statistically significant for fluoride solution (P=0.217. For S. Sobrinus, the mean diameter of inhibition zone around the discs coated with fluoride gel (F g, fluoride solution (F s, Chlorhexidine gel (CHX g and Chlorhexidine solution (CHX s were 19, 9, 21.5 and 27.5mm, respectively. For S. Sanguis, the mean diameter of inhibition zone around the discs coated with F g, F s, CHX g and CHX s were 17, 11, 17 and 25mm, respectively. CHX s had the most effect on both bacteria and F s had the least. CHX g and F g were less effective than CHX s, respectively. Conclusion: The results demonstrated that 2% CHX s and 1.23% F g can be effective on inhibition of the growth of some of cariogenic bacteria. Therefore, these agents can be used in the prevention of Early Childhood Caries.

  10. Endocrine disruptors and dental materials: health implications associated with their use in Brazil

    Directory of Open Access Journals (Sweden)

    Coelho Antonio Jorge Molinário

    2002-01-01

    Full Text Available This study analyzes international historical trends in the use of different types of materials in dental practice. The author describes the chemical properties of their ingredients and the potential and observed adverse effects in patients and dental technicians resulting from clinical or occupational exposure to various metals like beryllium, used to produce metal alloys. The growing use of various products (resin cements, ionomer cements, aesthetic restorative materials, resins, endodontal cements, and others based on the compound bisphenol-A, whose chemical structure is similar to that of estrogen. Considering the demographic and contemporary work force characteristics of those involved in dental practice in the Brazil, the study highlights the possible effect of the use of these materials in both male and female patients and all age strata, as well as in health professionals with occupational exposure to products containing bisphenol-A.

  11. Influence of fluoride on the bacterial composition of a dual-species biofilm composed of Streptococcus mutans and Streptococcus oralis.

    Science.gov (United States)

    Jung, Ji-Eun; Cai, Jian-Na; Cho, Sung-Dae; Song, Kwang-Yeob; Jeon, Jae-Gyu

    2016-10-01

    Despite the widespread use of fluoride for the prevention of dental caries, few studies have demonstrated the effects of fluoride on the bacterial composition of dental biofilms. This study investigated whether fluoride affects the proportion of Streptococcus mutans and S. oralis in mono- and dual-species biofilm models, via microbiological, biochemical, and confocal fluorescence microscope studies. Fluoride did not affect the bacterial count and bio-volume of S. mutans and S. oralis in mono-species biofilms, except for the 24-h-old S. mutans biofilms. However, fluoride reduced the proportion and bio-volume of S. mutans but did not decrease those of S. oralis during both S. oralis and S. mutans dual-species biofilm formation, which may be related to the decrease in extracellular polysaccharide formation by fluoride. These results suggest that fluoride may prevent the shift in the microbial proportion to cariogenic bacteria in dental biofilms, subsequently inhibiting the cariogenic bacteria dominant biofilm formation.

  12. Clinical evaluation of the intraoral fluoride releasing system in radiation-induced xerostomic subjects. Part 2: Phase I study.

    Science.gov (United States)

    Chambers, Mark S; Mellberg, James R; Keene, Harris J; Bouwsma, Otis J; Garden, Adam S; Sipos, Tibor; Fleming, Terence J

    2006-10-01

    Radiation-induced xerostomia can result in the rapid onset and progression of dental caries in head and neck cancer patients. Topically applied fluorides have been successfully used to inhibit the formation of dental caries in this population. However, because intensive daily self-application is required, compliance is an issue. The intraoral fluoride-releasing system (IFRS) containing a sodium fluoride core is a newly developed, sustained-release, passive drug delivery system that does not require patient involvement except for periodic replacement, thus reducing the effect of patient compliance on its effectiveness in dental caries prevention. Twenty-two head and neck cancer patients from U. T. M. D. Anderson Cancer Center, with radiation-induced xerostomia, were entered into a pilot study to contrast the daily home use of a 0.4% stannous fluoride-gel-containing tray (control group) to IFRS (study group) with respect to tolerability and adherence, and to obtain information on relative caries preventive efficacy. Participants were stratified on the basis of radiation exposure and randomly assigned to treatment with either IFRS or stannous fluoride gel. Patients in both groups were fitted with two IFRS retainers and also were instructed to use a 1100-ppm fluoride conventional sodium fluoride dentifrice twice daily. The study was conducted as a single-blinded, parallel-cell trial. Pre-existing carious lesions were restored prior to the beginning of the study. The efficacy variable was determined by the mean number of new or recurrent decayed surfaces. Patients were examined for caries 4, 8, 12, 24, 36, and 48 weeks after initiation of treatment. Reports of adverse reactions were based on information volunteered by patients and that were elicited during interviews. At baseline, the resting and stimulated salivary flow rates (g/5min) were significantly greater in the control group than in the study group (pIFRS groups during the study period. The rate of new or

  13. Enhanced anticaries efficacy of a 0.243% sodium fluoride/10% xylitol/silica dentifrice: 3-year clinical results.

    Science.gov (United States)

    Sintes, J L; Escalante, C; Stewart, B; McCool, J J; Garcia, L; Volpe, A R; Triol, C

    1995-10-01

    To evaluate the efficacy of a sodium fluoride (NaF)/silica/xylitol dentifrice compared with that of a positive control NaF/silica dentifrice on caries increments in school children over a 3-year period in an area without an optimal level of fluoride in the drinking water (mean level schools in the San Jose, Costa Rica metropolitan area. Clinical dental examinations were performed at participating schools utilizing portable dental equipment. Caries evaluations employed conventional tactile/visual methodology consisting of artificial light, dental mirrors and single-edge #23 explorers. Children accepted into the study were stratified by age and sex into two balanced groups within each school, and randomly assigned to use either a positive control dentifrice containing 0.243% NaF/silica or a test dentifrice containing 0.234% NaF/silica/10% xylitol. Children were instructed to brush with the assigned dentifrice twice daily. Caries evaluations were conducted at baseline, 2 years, and 3 years. After 3 years, subjects using the 0.234% NaF/silica/10% xylitol dentifrice had statistically significantly reduced decayed/filled surfaces (DFS; -12.3% reduction; P < or = 0.001) and decayed/filled buccal and lingual surfaces (DFS-BL; -10.5% reduction; P < or = 0/01).

  14. Dental caries: Strategies to control this preventable disease

    Directory of Open Access Journals (Sweden)

    Andrew Rugg-Gunn

    2013-11-01

    Full Text Available Objective. To provide a brief commentary review of strategies to control dental caries. Dental decay is one of man’s most prevalent diseases. In many counties, severity increased in parallel with importation of sugar, reaching its zenith about 1950s and 1960s. Since then, severity has declined in many countries, due to the wide use of fluoride especially in toothpaste, but dental caries remains a disease of medical, social and economic importance. Within the EU in 2011, the cost of dental treatment was estimated to be €79 billion. The pathogenesis is well understood: bacteria in dental plaque (biofilm metabolise dietary sugars to acids which then dissolve dental enamel and dentine. Possible approaches to control caries development, therefore, involve: removal of plaque, reducing the acidogenic potential of plaque, reduction in sugar consumption, increasing the tooth’s resistance to acid attack, and coating the tooth surface to form a barrier between plaque and enamel. At the present time, only three approaches are of practical importance: sugar control, fluoride, and fissure sealing. The evidence that dietary sugars are the main cause of dental caries is extensive, and comes from six types of study. Without sugar, caries would be negligible. Fluoride acts in several ways to aid caries prevention. Ways of delivering fluoride can be classed as: ‘automatic’, ‘home care’ and ‘professional care’: the most important of these are discussed in detail in four articles in this issue of the Acta Medica Academica. Conclusion. Dental caries is preventable – individuals, communities and countries need strategies to achieve this.

  15. Dental fluorosis and urinary fluoride concentration as a reflection of fluoride exposure and its impact on IQ level and BMI of children of Laxmisagar, Simlapal Block of Bankura District, W.B., India.

    Science.gov (United States)

    Das, Kousik; Mondal, Naba Kumar

    2016-04-01

    There has been growing public concern about intellectual performance of children at high levels of fluoride exposure. A cross-sectional study was conducted in Simlapal Block of Bankura District, West Bengal, to find out the relationship between fluoride (F) exposure as exposure dose (ED) with dental fluorosis (DF), urinary fluoride concentration (UF), intelligence quotient (IQ) and body mass index (BMI). Fifty groundwater samples were collected from the target area. One hundred forty-nine children belonging to age group 6 to 18 years were considered for this study. Experimental results reveal that mean F(-) concentration of that area is 2.11 mg/L (±SD 1.64). On the basis of F concentration in groundwater and water consumption pattern, ED was calculated to explore the impact of F(-) on DF, UF, IQ, and BMI. Paired t test results suggest that exposure rate of F does not show any significant differences ( severe > mild > very mild > questionable > normal conditions. The highest UF concentration was recorded as 17 mg/L, but the status of DF in the affected children was recorded as moderate. The results also reveal that ED has a positive correlation with DF (r = 0.299, P fluoride toxicity.

  16. Fluoride release and recharge behavior of a nano-filled resin-modified glass ionomer compared with that of other fluoride releasing materials.

    Science.gov (United States)

    Mitra, Sumita B; Oxman, Joe D; Falsafi, Afshin; Ton, Tiffany T

    2011-12-01

    To compare the long-term fluoride release kinetics of a novel nano-filled two-paste resin-modified glass-ionomer (RMGI), Ketac Nano (KN) with that of two powder-liquid resin-modified glass-ionomers, Fuji II LC (FLC) and Vitremer (VT) and one conventional glass-ionomer, Fuji IX (FIX). Fluoride release was measured in vitro using ion-selective electrodes. Kinetic analysis was done using regression analysis and compared with existing models for GIs and compomers. In a separate experiment the samples of KN and two conventional glass-ionomers, FIX and Ketac Molar (KM) were subjected to a treatment with external fluoride source (Oral-B Neutra-Foam) after 3 months of fluoride release and the recharge behavior studied for an additional 7-day period. The cumulative amount of fluoride released from KN, VT and FLC and the release profiles were statistically similar but greater than that for FIX at P coating of KN with its primer and of DY with its adhesive did not significantly alter the fluoride release behavior of the respective materials. The overall rate for KN was significantly higher than for the compomer DY. DY showed a linear rate of release vs. t and no burst effect as expected for compomers. The nanoionomer KN showed fluoride recharge behavior similar to the conventional glass ionomers FIX and KM. Thus, it was concluded that the new RMGI KN exhibits fluoride ion release behavior similar to typical conventional and RMGIs and that the primer does not impede the release of fluoride.

  17. Galvanic Corrosion of and Ion Release from Various Orthodontic Brackets and Wires in a Fluoride-containing Mouthwash.

    Science.gov (United States)

    Tahmasbi, Soodeh; Ghorbani, Mohammad; Masudrad, Mahdis

    2015-01-01

    Background and aims. This study compared the galvanic corrosion of orthodontic wires and brackets from various manufacturers following exposure to a fluoride mouthwash. Materials and methods. This study was conducted on 24 lower central incisor 0.022" Roth brackets of four different commercially available brands (Dentaurum, American Orthodontics, ORJ, Shinye). These brackets along with stainless steel (SS) or nickel-titanium (NiTi) orthodontic wires (0.016", round) were immersed in Oral-B mouthwash containing 0.05% sodium fluoride for 28 days. The electric potential (EP) difference of each bracket-wire couple was measured with a Saturated Calomel Reference Electrode (Ag/AgCl saturated with KCl) via a voltmeter. The ions released in the electrolyte weremeasured with an atomic absorption spectrometer. All the specimens were assessed under a stereomicroscope and specimens with corrosion were analyzed with scanning electron microscopy (SEM). Data were analyzed using ANOVA. Results. The copper ions released from specimens with NiTi wire were greater than those of samples containing SS wire. ORJ brackets released more Cu ions than other samples. The Ni ions released from Shinye brackets were significantly more than those of other specimens (P brackets coupled with NiTi wires was higher than that of brackets coupled with SS wires. Light and electron microscopic observations showed greater corrosion of ORJ brackets. Conclusion. In fluoride mouthwash, Shinye and ORJ brackets exhibited greater corrosion than Dentaurum and American Orthodontics brackets. Stainless steel brackets used with NiTi wires showed greater corrosion and thus caution is recommended when using them.

  18. Utilization of toothpaste and fluoride content in toothpaste manufactured in Tanzania.

    Science.gov (United States)

    Kikwilu, Emil N; Frencken, Jo E; Mulder, Jan

    2008-10-01

    To determine the use of toothpaste, the reasons behind its irregular use, the cost perceptions, and the fluoride concentrations in locally manufactured toothpaste. A total of 978 dental patients attending 13 dental clinics for 2 weeks in June 2007 completed a pre-tested questionnaire on toothpaste use. Toothpaste was collected from shops in Dar es Salaam and analyzed at the laboratory of the Dental School in Amsterdam. Logistic regression was applied to determine the relative importance of independent variables on usage and perceptions about the cost of toothpaste. Eighty-six percent of respondents used toothpaste daily. Of the 130 who used toothpaste less than once a day, 57.7% gave financial reasons for their irregular use. Toothpaste was perceived as expensive by 34.8% of respondents. Urban residents were five times more likely than rural residents to use toothpaste. Younger respondents were more likely than older respondents: to perceive toothpaste as important, to brush their teeth, to use toothpaste, and to brush their teeth regularly. All toothpaste manufactured in Tanzania had free fluoride concentrations below 400 ppm. Most respondents used toothpaste regularly and one-third regarded it as expensive. Toothpaste manufactured in Tanzania had free fluoride concentrations below the optimum levels for dental caries prevention. For a well-functioning Basic Package of Oral Care, the authority responsible for oral health has to take measures aimed at lowering the price of toothpaste, and toothpaste manufacturers have to ensure that their products have the optimal fluoride concentration for dental caries prevention.

  19. Adsorption of fluoride ions onto naturally occurring earth materials ...

    African Journals Online (AJOL)

    Batch sorption system using two naturally occurring earth materials (EM) as adsorbents was investigated to remove fluoride ions from aqueous solution. The system variables studied include initial concentration of the sorbate, agitation time, adsorbent dose, pH, co-ions and temperature. The experimental data fitted well to ...

  20. Cost-effectiveness of preventing dental caries and full mouth dental reconstructions among Alaska Native children in the Yukon–Kuskokwim delta region of Alaska

    Science.gov (United States)

    Atkins, Charisma Y.; Thomas, Timothy K.; Lenaker, Dane; Day, Gretchen M.; Hennessy, Thomas W.; Meltzer, Martin I.

    2016-01-01

    Objective We conducted a cost-effectiveness analysis of five specific dental interventions to help guide resource allocation. Methods We developed a spreadsheet-based tool, from the healthcare payer perspective, to evaluate the cost effectiveness of specific dental interventions that are currently used among Alaska Native children (6-60 months). Interventions included: water fluoridation, dental sealants, fluoride varnish, tooth brushing with fluoride toothpaste, and conducting initial dental exams on children caries treatments completed by a dental provider in the dental chair, while 161 children received FMDRs completed by a dental surgeon in an operating room. The average cost of treating dental caries in the dental chair was $1,467 (~258,000 per year); while the cost of treating FMDRs was $9,349 (~1.5 million per year). All interventions were shown to prevent caries and FMDRs; however tooth brushing prevented the greatest number of caries at minimum and maximum effectiveness with 1,433 and 1,910, respectively. Tooth brushing also prevented the greatest number of FMDRs (159 and 211) at minimum and maximum effectiveness. Conclusions All of the dental interventions evaluated were shown to produce cost savings. However, the level of that cost saving is dependent on the intervention chosen. PMID:26990678

  1. Probing ge distribution in zeolite frameworks by post-synthesis introduction of fluoride in as-made materials

    KAUST Repository

    Liu, Xiaolong; Ravon, Ugo; Bosselet, Franç oise; Bergeret, Gé rard; Tuel, Alain

    2012-01-01

    A new method has been developed to introduce fluoride in the structure of as-made germanium-containing zeolites prepared under pure alkaline media. Incorporation of fluoride species occurs without modification of the framework composition (Si

  2. New Insight on the Response of Bacteria to Fluoride

    Science.gov (United States)

    Breaker, R.R.

    2012-01-01

    Fluoride has been used for decades to prevent caries and it is well established that this anion can inhibit the growth of bacteria. However, the precise effects that fluoride has on bacteria and the mechanisms that bacteria use to overcome fluoride toxicity have largely remained unexplored. Recently, my laboratory reported the discovery of biological systems that bacteria use to sense fluoride and reduce fluoride toxicity. These sensors and their associated genes are very widespread in biology, which has implications for a number of issues that are central to the use of fluoride for dental care. Below I provide a summary of our findings, comment on some of the key prospects for expanding our understanding of fluoride's effects on biology, and propose some future uses of this knowledge. PMID:22327376

  3. New insight on the response of bacteria to fluoride.

    Science.gov (United States)

    Breaker, R R

    2012-01-01

    Fluoride has been used for decades to prevent caries and it is well established that this anion can inhibit the growth of bacteria. However, the precise effects that fluoride has on bacteria and the mechanisms that bacteria use to overcome fluoride toxicity have largely remained unexplored. Recently, my laboratory reported the discovery of biological systems that bacteria use to sense fluoride and reduce fluoride toxicity. These sensors and their associated genes are very widespread in biology, which has implications for a number of issues that are central to the use of fluoride for dental care. Below I provide a summary of our findings, comment on some of the key prospects for expanding our understanding of fluoride's effects on biology, and propose some future uses of this knowledge. Copyright © 2012 S. Karger AG, Basel.

  4. FLUORIDE: A REVIEW OF USE AND EFFECTS ON HEALTH

    OpenAIRE

    Kanduti, Domen; Sterbenk, Petra; Artnik, Barbara

    2016-01-01

    Introduction: Appropriate oral health care is fundamental for any individual?s health. Dental caries is still one of the major public health problems. The most effective way of caries prevention is the use of fluoride. Aim: The aim of our research was to review the literature about fluoride toxicity and to inform physicians, dentists and public health specialists whether fluoride use is expedient and safe. Methods: Data we used in our review were systematically searched and collected from web...

  5. Evaluation of the anti-cariogenic potential and bond strength to enamel of different fluoridated materials used for bracket bonding

    OpenAIRE

    SILVA, Sérgio Ricardo da; SILVA, Luciana Alves Herdy da; BASTING, Roberta Tarkany; LIMA-ARSATI, Ynara Bosco de Oliveira

    2017-01-01

    Abstract Objective To evaluate the in vitro and in situ anti-cariogenic potential and bond strength to enamel of materials containing fluoride (F), used for bracket bonding: Transbond XT (GT, negative control), Transbond Plus Color Change (GTF), Transbond-Self-Etching Primer (GSAF) and Vitremer (GV, positive control). Material and method In the in vitro study, the specimens were premolars with bonded brackets (n=12/group). After pH cycling, the F release, bond strength, fracture mode and pr...

  6. Anisotropic local physical properties of human dental enamel in comparison to properties of some common dental filling materials.

    Science.gov (United States)

    Raue, Lars; Hartmann, Christiane D; Rödiger, Matthias; Bürgers, Ralf; Gersdorff, Nikolaus

    2014-11-01

    A major aspect in evaluating the quality of dental materials is their physical properties. Their properties should be a best fit of the ones of dental hard tissues. Manufacturers give data sheets for each material. The properties listed are characterized by a specific value. This assumes (but does not prove) that there is no direction dependence of the properties. However, dental enamel has direction-dependent properties which additionally vary with location in the tooth. The aim of this paper is to show the local direction dependence of physical properties like the elastic modulus or the thermal expansion in dental hard tissues. With this knowledge the 'perfect filling/dental material' could be characterized. Enamel sections of ∼400-500 μm thickness have been cut with a diamond saw from labial/buccal to palatal/lingual (canine, premolar and molar) and parallel to labial (incisor). Crystallite arrangements have been measured in over 400 data points on all types of teeth with x-ray scattering techniques, known from materials science. X-ray scattering measurements show impressively that dental enamel has a strong direction dependence of its physical properties which also varies with location within the tooth. Dental materials possess only little or no property direction dependence. Therefore, a mismatch was found between enamel and dental materials properties. Since dental materials should possess equal (direction depending) properties, worthwhile properties could be characterized by transferring the directional properties of enamel into a property 'wish list' which future dental materials should fulfil. Hereby the 'perfect dental material' can be characterized.

  7. Formation of hydrogen fluoride by gamma and beta sterilisation in medical devices containing perfluoroheptane

    International Nuclear Information System (INIS)

    Zuendorf, Josef; Kremer, Stefan; Grueger, Thomas

    2008-01-01

    Infusion of hexadecafluoroheptane, a liquid perfluorocarbon released from repaired Althane dialysers was found to be the most probable reason for the deaths of 53 dialysis patients reported in the year 2001. This study focuses on toxic decomposition products generated due to gamma and beta sterilisation of hexadecafluoroheptane. The responsible dialysers were sterilised with a maximum dose of 45 kGy gamma irradiation. We investigated the influence of both 20-500 kGy gamma and beta irradiation on perfluoroheptane. Analysis of the irradiated samples verified the decomposition of perfluoroheptane in dependence on the dose of irradiation. Beta irradiation resulted in a higher degree of decomposition than the same dose of gamma irradiation. As decomposition products, hydrogen fluoride, CO 2 , and one saturated fluorinated hydrocarbon which could not be analysed exactly were identified. Even at 20 kGy gamma irradiation hydrogen fluoride was detectable. Our results provide evidence that hydrogen fluoride is generated as a highly toxic decomposition product when perfluoroheptane is sterilised with gamma irradiation as it was applied on the affected dialysers. There is no evidence of other toxic degradation products especially perfluoroisobutylene. Therefore, hydrogen fluoride or the dissociated fluoride ions might act as a toxic agent when medical devices containing liquid perfluorocarbons are sterilised by irradiation

  8. The Historical Evolution of Dental Impression Materials.

    Science.gov (United States)

    Papadiochos, Ioannis; Papadiochou, Sofia; Emmanouil, Ioannis

    The concept of impression making process in dentistry began in the mid 1800s. Dentists realized that the construction of a prosthetic restoration required both a detailed capture of the oral tissues along with stone cast fabrications. To accomplish these goals, impression materials were essential. Beeswax represents the first impression material, while important bechmarks during the historical evolution of dental impression materials are considered to be the introduction of dental trays in the early 1800s and the invention of the gutta-percha, thermoplastic resins and plaster of Paris. The double (corrective) impression technique, along with the functional impression concept that was established after mid 1800s, are also identified as pivotal innovations. During the 20th century, the advances in material development slowed significantly since the majority of the current impression materials had already been invented. However, the introduction of elastomeric impression materials in the field of prosthodontics that offered the advantages of accuracy and dimensional stability substantially upgraded both the impression accuracy and the quality of the final restoration. Presently, the dental practitioner has access to a variety of impression materials and should be aware of their properties, indications and limitations as well. Futhermore, while continuous attempts are being made to enhance these materials, the ideal impression material has yet to be developed. The purpose of this article was to provide a comprehensive review about the historical development of impression dental materials. Copyright American Academy of the History of Dentistry.

  9. Exploring the determinants of secular decreases in dental caries among Korean children.

    Science.gov (United States)

    Lee, Hye-Ju; Han, Dong-Hun

    2015-08-01

    The aim of this study was to determine the contributions of sealant and water fluoridation to the time trends in dental caries from 2003 to 2010. Data were from three waves of the Korean National Oral Health Surveys between 2003 and 2010, including a total of 23 059 children (11 889 boys and 11 170 girls) aged 8, 10, and 12 years. The impacts of sealant and water fluoridation on dental caries were obtained by logistic regression for each age group of children. The contributions of sealant and water fluoridation to the time trends in the prevalence of dental caries were examined by a series of logistic regression models, and changes in the adjusted odds ratios for each survey year were also calculated. Over the past 7 years, the prevalence of dental caries decreased dramatically. Although sealant had a significant impact on dental caries in each survey year, remarkable decreases in dental caries from 2003 to 2010 were not explained by the secular changes in the dental sealant or water fluoridation factor. We observed important population declines in dental caries in Korea in children aged 8-12 years; however, the likely causes for these secular trends remain to be determined. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  10. Students' perceptions of materials and techniques used at European dental schools in the education of fixed prosthodontics

    NARCIS (Netherlands)

    Brand, H.S.; Kamell, H.; Kharbanda, A.; Dozic, A.

    2013-01-01

    The aim of this study was to explore the materials and procedures used by students in dental schools across Europe for teaching fixed prosthodontics. An online questionnaire, containing twenty-eight dichotomous, multiple-choice, and Likert scale rating questions, was sent to students in forty dental

  11. Are there good reasons for fluoride labelling of food and drink?

    Science.gov (United States)

    Zohoori, F V; Maguire, A

    2018-02-23

    This opinion piece highlights the importance of controlling systemic fluoride intake from food and drink in early childhood to minimise risk of dental fluorosis whilst maximising caries prevention; the wide range of fluoride contents found in a study of commercially-available food and drinks; and the need for comprehensive fluoride labelling on food and drink products in the UK, particularly those used by infants and young children.

  12. Seasonal Variation in Fluoride Content in Groundwaters of Langtang Area, Northcentral Nigeria

    Science.gov (United States)

    Dibal, H. U.; Dajilak, W. N.; Lekmang, I. C.; Nimze, L. W.; Yenne, E. Y.

    2017-06-01

    Thirty groundwater samples were collected at the peak of the rainy season and analysed for fluoride and other cations and anions in drinking water sources of Langtang area. For comparative purposes, thirty seven groundwater samples were collected in the dry season. The aim of the study was to determine variation in fluoride content with respect to the seasons. Fluoride in water was determined by the Ion Selective Electrode (ISE) and the cations by the Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES). The anion (sulphate) was determined by Multi - Ion Colorimeter, bicarbonate and chloride by titration method. In addition fluorine content in aquifer materials from a borehole section were determined by Fusion method. The two seasons show variation in content of fluoride in groundwater. Fluoride content in groundwater is higher in the dry season ranging from 0.13 - 10.3 mg/l compared to the 0.06 - 4.60 mg/l values in the rainy season. Content of fluorine (0.01 wt %) in the aquifer materials (sands) is low from depth of 0 to 7.95 m. However, fluorine content increases with depth, from 7.95 to 10.60 m with concentration of 0.04 wt %, 0.05 wt % from 10.60 to 13.25m, and 0.07 wt % from 13.25 to 15.70 m, the content of fluorine however, decreased at depth 15.70 to18.55m with concentration of 0.02 wt % even with fluorite mineral in the aquifer material at this depth. Dilution of fluoride ion as a result of rain input which recharges the aquifer may be the main reason for lower values recorded in the rainy season. Over fifty and sixty percent of waters in both dry and rainy season have fluoride concentration above the WHO upper limit of 1.5 mg/l. Consumption of these elevated values of fluoride in groundwater of the study area, clearly manifests as symptoms of dental fluorosis.

  13. Seasonal Variation in Fluoride Content in Groundwaters of Langtang Area, Northcentral Nigeria

    Directory of Open Access Journals (Sweden)

    Dibal H.U.

    2017-06-01

    Full Text Available Thirty groundwater samples were collected at the peak of the rainy season and analysed for fluoride and other cations and anions in drinking water sources of Langtang area. For comparative purposes, thirty seven groundwater samples were collected in the dry season. The aim of the study was to determine variation in fluoride content with respect to the seasons. Fluoride in water was determined by the Ion Selective Electrode (ISE and the cations by the Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES. The anion (sulphate was determined by Multi – Ion Colorimeter, bicarbonate and chloride by titration method. In addition fluorine content in aquifer materials from a borehole section were determined by Fusion method. The two seasons show variation in content of fluoride in groundwater. Fluoride content in groundwater is higher in the dry season ranging from 0.13 – 10.3 mg/l compared to the 0.06 – 4.60 mg/l values in the rainy season. Content of fluorine (0.01 wt % in the aquifer materials (sands is low from depth of 0 to 7.95 m. However, fluorine content increases with depth, from 7.95 to 10.60 m with concentration of 0.04 wt %, 0.05 wt % from 10.60 to 13.25m, and 0.07 wt % from 13.25 to 15.70 m, the content of fluorine however, decreased at depth 15.70 to18.55m with concentration of 0.02 wt % even with fluorite mineral in the aquifer material at this depth. Dilution of fluoride ion as a result of rain input which recharges the aquifer may be the main reason for lower values recorded in the rainy season. Over fifty and sixty percent of waters in both dry and rainy season have fluoride concentration above the WHO upper limit of 1.5 mg/l. Consumption of these elevated values of fluoride in groundwater of the study area, clearly manifests as symptoms of dental fluorosis.

  14. Contribution to the study of transport and diffusion properties inside fluoride glasses based on zirconium tetrafluoride

    International Nuclear Information System (INIS)

    Bobe, Jean-Marc

    1995-01-01

    This research thesis addresses the study of electric and diffusion properties of fluoride and fluorine-oxide glasses based on zirconium tetrafluoride, and more specifically in the case either of glasses free of alkaline fluoride, or of glasses containing lithium fluoride or sodium fluoride. Some techniques have been systematically used for this purpose: impedance spectroscopy, and NMR of Fluorine 19, lithium 7 or sodium 23 atoms. The objectives were to determine: 1) the presence or absence of different sites for fluorine ions and, should the occasion occurs, the distribution of these ions among the different sites; 2) the nature and number of mobile ions within these materials; 3) the role played by alkaline ions in these materials. After a presentation of experimental techniques, the author reports the comparative study of electric and diffusion properties of some sets of fluorinated glasses free of alkaline fluoride, and, for comparative purposes, of some crystallized phases having a similar composition. Two chapters respectively address the study of fluorinated glasses containing sodium fluoride and of fluorinated glasses containing sodium fluoride. Then, by applying the Almond-West model to some glasses containing NaF, conductivity parameters (number of carriers, mobility, entropic factor, and so on) have been assessed for a wide range of temperatures and frequencies. Movements of F ions determined by impedance spectroscopy are compared with those obtained by NMR. [fr

  15. Mechanical behaviour of dental composite filling materials using digital holography

    OpenAIRE

    Monteiro, J.M.; Lopes, H.; Vaz, M.A.P.; Campos, J.C. Reis

    2010-01-01

    One of the most common clinical problems in dentistry is tooth decay. Among the dental filling materials used to repair tooth structure that has been destroyed by decay are dental amalgam and composite materials based on acrylics. Dental amalgam has been used by dentists for the past 150 years as a dental restorative material due to its low cost, ease of application, strength, durability, and bacteriostatic effects. However its safety as a filling material has been questioned due to th...

  16. THE USE OF FLUORIDE AND ITS EFFECT ON HEALTH

    Directory of Open Access Journals (Sweden)

    Domen Kanduti

    2016-07-01

    Full Text Available Appropriate oral health care is fundamental for any individual’s health. Dental caries is still one of the major public health problems. The most effective way of caries prevention is the use of fluoride. Fluoride occurs naturally in our environment and is always present in our lives. However, the concentration differs from area to area. Exposure can occur through diet, respiration and fluoride supplements. During pregnancy, the placenta acts as a barrier. The fluoride, therefore, crosses the placenta in low concentrations. Drinking water in Slovenia is not fluoridated; the amount of naturally present fluoride is very low. Fluoride can be toxic in extremely high concentrations. The most important effect of fluoride on caries incidence is through its role in the process of remineralisation and demineralisation of tooth enamel. The European Academy of Paediatric Dentistry (EAPD recommends a preventive topical use of fluoride supplements because of their cariostatic effect. 

  17. Erratum to "Clinical evaluation of the intraoral fluoride releasing system in radiation-induced xerostomic subjects. Part 2: Phase I study".

    Science.gov (United States)

    Chambers, Mark S; Fleming, Terence J; Toth, Béla B; Lemon, James C; Craven, Timothy E; Bouwsma, Otis J; Garden, Adam S; Espeland, Mark A; Keene, Harris J; Martin, Jack W; Sipos, Tibor

    2007-01-01

    Radiation-induced xerostomia can result in the rapid onset and progression of dental caries in head and neck cancer patients. Topically applied fluorides have been successfully used to inhibit the formation of dental caries in this population. However, because intensive daily self-application is required, compliance is an issue. The intraoral fluoride-releasing system (IFRS) containing a sodium fluoride core is a newly developed, sustained-release, passive drug delivery system that does not require patient involvement except for periodic replacement, thus reducing the effect of patient compliance on its effectiveness in dental caries prevention. Twenty-two head and neck cancer patients from U. T. M. D. Anderson Cancer Center, with radiation-induced xerostomia, were entered into a pilot study to contrast the daily home use of a 0.4% stannous fluoride-gel-containing tray (control group) to IFRS (study group) with respect to tolerability and adherence, and to obtain information on relative caries preventive efficacy. Participants were stratified on the basis of radiation exposure and randomly assigned to treatment with either IFRS or stannous fluoride gel. Patients in both groups were fitted with two IFRS retainers and also were instructed to use a 1100-ppm fluoride conventional sodium fluoride dentifrice twice daily. The study was conducted as a single-blinded, parallel-cell trial. Pre-existing carious lesions were restored prior to the beginning of the study. The efficacy variable was determined by the mean number of new or recurrent decayed surfaces. Patients were examined for caries 4, 8, 12, 24, 36, and 48 weeks after initiation of treatment. Reports of adverse reactions were based on information volunteered by patients and that were elicited during interviews. At baseline, the resting and stimulated salivary flow rates (g/5min) were significantly greater in the control group than in the study group (pIFRS groups during the study period. The rate of new or

  18. Fluorides and Other Preventive Strategies for Tooth Decay.

    Science.gov (United States)

    Horst, Jeremy A; Tanzer, Jason M; Milgrom, Peter M

    2018-04-01

    We focus on scalable public health interventions that prevent and delay the development of caries and enhance resistance to dental caries lesions. These interventions should occur throughout the life cycle, and need to be age appropriate. Mitigating disease transmission and enhancing resistance are achieved through use of various fluorides, sugar substitutes, mechanical barriers such as pit-and-fissure sealants, and antimicrobials. A key aspect is counseling and other behavioral interventions that are designed to promote use of disease transmission-inhibiting and tooth resistance-enhancing agents. Advocacy for public water fluoridation and sugar taxes is an appropriate dental public health activity. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. Some metallic materials and fluoride salts for high temperature applications

    International Nuclear Information System (INIS)

    Hosnedl, P.; Hron, M.; Matal, O.

    2009-01-01

    There has been a special Ni base alloy MONICR for high temperature applications in fluoride salt environments developed in the framework of the complex R and D program for the Molten Salt Reactor (MSR) - SPHINX (SPent Hot fuel Incinerator by Neutron fluX) concept development in the Czech Republic. Selected results of MONICR alloy tests and results of semi products fabrication from this alloy are discussed in the paper. The results of the structural materials tests are applied on semi-products and for the design of the testing devices as the autoclave in loop arrangement for high temperature fluoride salts applications. Material properties other Ni base alloys are compared to those of MONICR. Corrosion test results of the alloy A686 in the LiF - NaF - ZrF 4 molten salt are provided and compared to the measured values of the polarizing resistance. (author)

  20. Parental preference for fluoride varnish: a new concept in a rapidly developing nation.

    Science.gov (United States)

    Hendaus, Mohamed A; Jama, Hibaq A; Siddiqui, Faisal J; Elsiddig, Sohair A; Alhammadi, Ahmed H

    2016-01-01

    The objective of this study was to investigate parental preference for fluoride varnish in a country where the average percentage of dental caries in young children is up to ~73%. Consequently, the aim of this study, despite being a pilot, was to create a nationwide project in the State of Qatar to promote oral health in children. A cross-sectional perspective study was conducted at Hamad Medical Corporation in Qatar. Parents of children aged ≤5 years were offered an interview survey. A total of 200 questionnaires were completed (response rate =100%). The study was conducted between December 1, 2014 and March 30, 2015, and included all children aged >1 year and parents' knowledge and awareness of dental health, we found that >90% of families were aware that dental health affects the health of the whole body. The study showed that ~70% of parents were not aware of the existence of fluoride varnish, but would allow a health provider to apply fluoride varnish. Furthermore, ~80% of parents would not stop brushing their child's teeth and would not skip dentist appointments if varnish was to be applied. Approximately 40% of parents conveyed some concerns regarding the safety of fluoride varnish, despite being considered as a new concept. The main concern was that the child might swallow some of the fluoride. Another important concern expressed by parents was the availability of the fluoride varnish in all clinics. The robust positive attitude of parents in this sample suggests that introducing fluoride varnish is feasible and acceptable in our community. Actions to augment fluoride varnish acceptability in the developing world, such as focusing on safety, could be important in the disseminated implementation of fluoride varnish.

  1. Galvanic Corrosion of and Ion Release from Various Orthodontic Brackets and Wires in a Fluoride-containing Mouthwash

    Directory of Open Access Journals (Sweden)

    Soodeh Tahmasbi

    2015-09-01

    Full Text Available Background and aims. This study compared the galvanic corrosion of orthodontic wires and brackets from various man-ufacturers following exposure to a fluoride mouthwash. Materials and methods. This study was conducted on 24 lower central incisor 0.022” Roth brackets of four different commercially available brands (Dentaurum, American Orthodontics, ORJ, Shinye. These brackets along with stainless steel (SS or nickel-titanium (NiTi orthodontic wires (0.016", round were immersed in Oral-B mouthwash containing 0.05% sodium fluoride for 28 days. The electric potential (EP difference of each bracket-wire couple was measured with a Satu-rated Calomel Reference Electrode (Ag/AgCl saturated with KCl via a voltmeter. The ions released in the electrolyte weremeasured with an atomic absorption spectrometer. All the specimens were assessed under a stereomicroscope and speci-mens with corrosion were analyzed with scanning electron microscopy (SEM. Data were analyzed using ANOVA. Results. The copper ions released from specimens with NiTi wire were greater than those of samples containing SS wire. ORJ brackets released more Cu ions than other samples. The Ni ions released from Shinye brackets were significantly more than those of other specimens (P < 0.05. Corrosion rate of brackets coupled with NiTi wires was higher than that of brack-ets coupled with SS wires. Light and electron microscopic observations showed greater corrosion of ORJ brackets. Conclusion. In fluoride mouthwash, Shinye and ORJ brackets exhibited greater corrosion than Dentaurum and American Orthodontics brackets. Stainless steel brackets used with NiTi wires showed greater corrosion and thus caution is recom-mended when using them.

  2. Dental caries prevalence in children up to 36 months of age attending daycare centers in municipalities with different water fluoride content

    Directory of Open Access Journals (Sweden)

    Ana Valéria Pagliari Tiano

    2009-02-01

    Full Text Available This study determined the prevalence of cavitated caries lesions (CCL and early childhood caries (ECC, and the contribution of some variables in children up to 36 months of age attending daycare centers in municipalities with different fluoride levels in the water supply: AFC (adequate fluoride content and LFC (low fluoride content. After approval of the Ethics Committee, the parents were interviewed. The children were clinically examined using the same codes and criteria established by the WHO (World Health Organization and the ADA (American Dental Association. Fisher's exact test (p<0.05 was applied for statistical analysis of data. The dmft indices calculated in the LFC and AFC municipalities were 0.57 and 0.68, respectively. Considering all children examined, 17.6% presented CCL and 33.8% ECC. The economic classification, mother's education level and duration of breastfeeding were considered statistically significant with regards to CCL prevalence. The age group, duration of the habit of drinking milk before bedtime and age at which oral hygiene started were considered statistically significant with regards to ECC prevalence.

  3. PERBEDAAN TOPICAL FLUORIDE APPLICATION DAN FISSURE SEALANT DALAM MENCEGAH KARIES PADAGIGI MOLAR SATU

    Directory of Open Access Journals (Sweden)

    Pawarti Pawarti

    2017-07-01

    Full Text Available Abstract: Topical Fluoride Application And Fissure Sealant To Prevent Dental Caries Permanent First Molars. Anatomy pits and fissures of teeth are caries initiation vulnerable areas of the permanent molars that grow at the age of 6 years where children can not perform oral hygiene. Caries prevention can be done by closing the pits and fissures or application of fluoride (topical fluoride application on the surface of the teeth. The purpose of this study was to analyze the difference fissure sealants and topical application of fluoride to prevent dental caries of first permanent molars. This study was a quasi-experimental study with time series, a sample was taken by purposive 117-second grade students of SDN District of North Pontianak. Data were analyzed using t-test. The result showed that fissure sealant more effective in caries prevention of first permanent molar than topical fluoride application where there were none caries teeth after and month fissure sealant, 25% sealant partially off and 11% fully off. Teeth that have done fluoride after 6 months of 3.9% of dental caries, the eighth month of 5.4% of dental caries. There was a significant difference between the effectiveness of fissure sealants with topical application of fluoride to prevent dental caries in first permanent molars p-value < 0.05, after 6-month p-value: 0.004 and after 8-month p-value: 0.001. Abstrak: Topical Fluoride Application Dan Fissure Sealant Untuk Mencegah Karies Pada Gigi Molar Satu Permanen. Anatomi pit dan fisura gigi merupakan daerah rentan inisiasi karies gigi molar satu permanen yang tumbuh pada usia 6 tahun anak belum bisa melakukan kebersihan mulutnya. Pencegahan karies dapat dilakukan dengan cara menutup pit dan fissure atau pengolesan fluor (topical fluoride application pada permukaan gigi. Tujuan penelitian ini untuk menganalisis perbedaan efektivitas fissure sealant dan topical fluoride application untuk mencegah karies gigi molar satu permanen anak

  4. In vitro study of demineralization resistance and fluoride retention in dental enamel irradiated with Er,Cr: YSGG laser

    International Nuclear Information System (INIS)

    Ana, Patricia Aparecida da.

    2007-01-01

    This study aimed to establish irradiation conditions of Er,Cr:YSGG laser (λ of 2.79 μm) which could propitiate changes on human dental enamel and increase its resistance to demineralization, when associated or not with topical application of acidulated phosphate fluoride (APF). Fluences of 2,8 J/cm 2 , 5,6 J/cm 2 e 8,5 J/cm 2 were selected; they were associated or not with previous application of a photo absorber (coal paste) and then APF was applied or not after laser irradiation. In a first step, the morphological findings, the surface temperatures, and the pupal temperatures were evaluated during laser irradiation. After that, the treated samples were submitted to a a ten-day pH-cycling model. After producing the incipient white-spots lesions, the following aspects were evaluated: the mineral loss, the loosely bound fluoride and the firmly bound fluoride. All the demineralizing and remineralizing pH-cycling solutions were evaluated with respect to their calcium (Ca), inorganic phosphorous (Pi) and fluoride (F - ) concentrations. The data had their normality and homogeneity distribution statistically evaluated, and it was chosen an appropriated statistical test for each performed analysis according to the obtained results, considering 5% significant level. The fluences selected for this study created ablated surfaces; the fluences of 5.6 J/cm 2 and 8.5 J/cm 2 promoted increments in surface temperature above 110 deg C. The intrapupal temperature changes revealed that laser irradiation did not increase the pulpal temperatures above the critical threshold for induction of pulpitis. The coal paste did not promote any changes on surface morphology or in the intrapulpal temperature changes; however, this paste increased the surface temperatures during laser irradiation. Only laser irradiation at 8.5 J/cm 2 was able to decrease the mineral loss when compared to the no-treatment group; although the association of coal paste + laser at 2.8 J/cm 2 + APF application

  5. Method of converting uranium fluoride to intermediate product for uranium oxide manufacture with recycling or reusing valuable materials

    International Nuclear Information System (INIS)

    Baran, V.; Moltasova, J.

    1982-01-01

    Uranium fluoride is acted upon by water with nitrate containing a cation capable of binding fluoride ions. The uranium is extracted, for instance, with tributyl phosphate with the generated organic phase containing the prevalent proportion of uranium and representing the required intermediate product and the aqueous phase from which is isolated the fluorine component which may be used within the fuel cycle. The nitrate component of the aqueous phase is recycled following treatment. It is also possible to act on uranium fluoride directly with an aqueous solution. Here the cations of nitrate form with the fluorides soluble nondissociated complexes and reduce the concentration of free fluoride ions. The nitrate +s mostly used in an amount corresponding to its solubility in the system prior to the introduction of UF 6 . The uranium from the solution with the reduced concentration of free fluoride ions is extracted into the reaction system under such conditions as to make the prevalent majority of fluorides and an amount of uranium smaller than 5x10 -2 mol/l remain in the aqueous phase and that such an amount of fluorides should remain in the organic phase which is smaller than corresponds to the fluorine/uranium molar ratio in the organic phase. Uranium contained in the organic phase is processed into uranium oxide, with advantage into UO 2 . From the isolated compounds of fluorine and the cation of the nitrate gaseous HF is released which is used either inside or outside of the fuel cycle. (J.P.)

  6. Evaluation of patients with oral lichenoid lesions by dental patch testing and results of removal of the dental restoration material

    Directory of Open Access Journals (Sweden)

    Emine Buket Şahin

    2016-12-01

    Full Text Available Background and Design: Oral lichenoid lesions (OLL are contact stomatitis characterized by white reticular or erosive patches, plaque-like lesions that are clinically and histopathologically indistinguishable from oral lichen planus (OLP. Amalgam dental fillings and dental restoration materials are among the etiologic agents. In the present study, it was aimed to evaluate the standard and dental series patch tests in patients with OLL in comparison to a control group and evaluate our results. Materials and Methods: Thirty-three patients with OLL or OLP and 30 healthy control subjects, who had at least one dental restoration material and/or dental filling, were included in the study. Both groups received standard series and dental patch test and the results were evaluated simultaneously. Results: The most frequent allergens in the dental series patch test in the patient group were palladium chloride (n=4; 12.12% and benzoyl peroxide (n=2, 6.06%. Of the 33 patients with OLL; 8 had positive reaction to allergents in the standard patch test series and 8 had positive reaction in the dental patch test series. There was no significant difference in the rate of patch test reaction to the dental and standard series between the groups. Ten patients were advised to have the dental restoration material removed according to the results of the patch tests. The lesions improved in three patients [removal of all amalgam dental fillings (n=1, replacement of all amalgam dental fillings with an alternative filling material (n=1 and replacement of the dental prosthesis (n=1] following the removal or replacement of the dental restoration material. Conclusion: Dental patch test should be performed in patients with OLL and dental restoration material. Dental filling and/or prosthesis should be removed/replaced if there is a reaction against a dental restoration material-related allergen.

  7. Recovery of plutonium from nitric acid containing oxalate and fluoride by a macroporous bifunctional phosphinic acid resin (MPBPA)

    International Nuclear Information System (INIS)

    Venugopal Chetty, K.; Godbole, A.G.; Swarup, R.; Vaidya, V.N.; Venugopal, V.; Vasudeva Rao, P.R.

    2006-01-01

    The sorption of Pu from nitric acid solutions containing oxalate/fluoride was studied using an indigenously available macroporous bifunctional phosphinic acid (MPBPA) resin. Batch experiments were carried out to obtain the distribution data of Pu(IV) with a view to optimize conditions for its recovery from nitric acid waste solutions containing oxalate or fluoride ions. The measurements showed high distribution ratio (D) values even in the presence of strong complexing ions, like oxalate and fluoride, indicating the possibility of recovery of Pu from these types of waste solution. Column studies were carried out using this resin to recover Pu from the oxalate supernatant waste solution, which showed that up to 99% of Pu could be adsorbed on the resin. Elution of Pu loaded on the resin was studied using different eluting agents. (author)

  8. Sirtuin1 and autophagy protect cells from fluoride-induced cell stress

    Science.gov (United States)

    Suzuki, Maiko; Bartlett, John D.

    2014-01-01

    Sirtuin1 (SIRT1) is an (NAD+)-dependent deacetylase functioning in the regulation of metabolism, cell survival and organismal lifespan. Active SIRT1 regulates autophagy during cell stress, including calorie restriction, endoplasmic reticulum stress and oxidative stress. Previously, we reported that fluoride induces endoplasmic reticulum (ER) stress in ameloblasts responsible for enamel formation, suggesting that ER-stress plays a role in dental fluorosis. However, the molecular mechanism of how cells respond to fluoride-induced cell stress is unclear. Here, we demonstrate that fluoride activates SIRT1 and initiates autophagy to protect cells from fluoride exposure. Fluoride treatment of ameloblast-derived cells (LS8) significantly increased Sirt1 expression and induced SIRT1 phosphorylation resulting in the augmentation of SIRT1 deacetylase activity. To demonstrate that fluoride exposure initiates autophagy, we characterized the expression of autophagy related genes (Atg); Atg5, Atg7 and Atg8/LC3 and showed that both their transcript and protein levels were significantly increased following fluoride treatment. To confirm that SIRT1 plays a protective role in fluoride toxicity, we used resveratrol (RES) to augmented SIRT1 activity in fluoride treated LS8 cells. RES increased autophagy, inhibited apoptosis, and decreased fluoride cytotoxicity. Rats treated with fluoride (0, 50 and 100 ppm) in drinking water for 6 weeks had significantly elevated expression levels of Sirt1, Atg5, Atg7 and Atg8/LC3 in their maturation stage enamel organs. Increased protein levels of p-SIRT1, ATG5 and ATG8/LC3 were present in fluoride-treated rat maturation stage ameloblasts. Therefore, the SIRT1/autophagy pathway may play a critical role as a protective response to help prevent dental fluorosis. PMID:24296261

  9. Sirtuin1 and autophagy protect cells from fluoride-induced cell stress.

    Science.gov (United States)

    Suzuki, Maiko; Bartlett, John D

    2014-02-01

    Sirtuin1 (SIRT1) is a nicotinamide adenine dinucleotide (NAD(+))-dependent deacetylase functioning in the regulation of metabolism, cell survival and organismal lifespan. Active SIRT1 regulates autophagy during cell stress, including calorie restriction, endoplasmic reticulum (ER) stress and oxidative stress. Previously, we reported that fluoride induces ER-stress in ameloblasts responsible for enamel formation, suggesting that ER-stress plays a role in dental fluorosis. However, the molecular mechanism of how cells respond to fluoride-induced cell stress is unclear. Here, we demonstrate that fluoride activates SIRT1 and initiates autophagy to protect cells from fluoride exposure. Fluoride treatment of ameloblast-derived cells (LS8) significantly increased Sirt1 expression and induced SIRT1 phosphorylation resulting in the augmentation of SIRT1 deacetylase activity. To demonstrate that fluoride exposure initiates autophagy, we characterized the expression of autophagy related genes (Atg); Atg5, Atg7 and Atg8/LC3 and showed that both their transcript and protein levels were significantly increased following fluoride treatment. To confirm that SIRT1 plays a protective role in fluoride toxicity, we used resveratrol (RES) to augment SIRT1 activity in fluoride treated LS8 cells. RES increased autophagy, inhibited apoptosis, and decreased fluoride cytotoxicity. Rats treated with fluoride (0, 50, 100 and 125ppm) in drinking water for 6weeks had significantly elevated expression levels of Sirt1, Atg5, Atg7 and Atg8/LC3 in their maturation stage enamel organs. Increased protein levels of p-SIRT1, ATG5 and ATG8/LC3 were present in fluoride-treated rat maturation stage ameloblasts. Therefore, the SIRT1/autophagy pathway may play a critical role as a protective response to help prevent dental fluorosis. Copyright © 2013 Elsevier B.V. All rights reserved.

  10. An In Vitro Study of the Effect of Fluoridated Milk on Oral Bacterial Biofilms

    Science.gov (United States)

    Pratten, J.; Bedi, R.; Wilson, M.

    2000-01-01

    Microcosmic dental plaques were grown in artificial saliva and supplemented with either milk or fluoridated milk. The presence of fluoride in the milk increased the pH of the biofilms and reduced the proportions of streptococci, demonstrating that in this model, fluoridation of milk produces biofilms with reduced cariogenic potential. PMID:10742268

  11. Advanced fluoride-based materials for energy conversion

    CERN Document Server

    Nakajima, Tsuyoshi

    2015-01-01

    Advanced Fluoride-Based Materials for Energy Conversion provides thorough and applied information on new fluorinated materials for chemical energy devices, exploring the electrochemical properties and behavior of fluorinated materials in lithium ion and sodium ion batteries, fluoropolymers in fuel cells, and fluorinated carbon in capacitors, while also exploring synthesis applications, and both safety and stability issues. As electronic devices, from cell phones to hybrid and electric vehicles, are increasingly common and prevalent in modern lives and require dependable, stable chemical energy devices with high-level functions are becoming increasingly important. As research and development in this area progresses rapidly, fluorine compounds play a critical role in this rapid progression. Fluorine, with its small size and the highest electronegativity, yields stable compounds under various conditions for utilization as electrodes, electrolytes, and membranes in energy devices. The book is an ideal reference f...

  12. Effect of sodium fluoride in maternal and offspring rats and its amelioration

    Directory of Open Access Journals (Sweden)

    Sneha Panchal

    2014-03-01

    Full Text Available High fluoride content is known to cause dental and skeletal abnormalities. In addition, present review indicates that sodium fluoride consumption caused increased number of r=esorptions and dead foetuses. Various skeletal anomalies such as wavy ribs, presence of 14th ribs, lacking 6th sternebrae and incompete ossification of skull occur. All these changes could be due to oxidative stress caused by fluoride consumption. Fluoride-induced changes could be successfully ameliorated by cotreatment with vitamins and calcium.

  13. Sociodemographic and behavioural correlates of severe dental fluorosis.

    Science.gov (United States)

    Wondwossen, F; Astrøm, A N; Bjorvatn, K; Bårdsen, A

    2006-03-01

    The aim of this study was to identify sociodemographic and behavioural factors associated with the prevalence of severe dental fluorosis in moderate- and high-fluoride areas of the Ethiopian Rift Valley. Three hundred and six adolescents (12-15 years) and 233 mothers participated in the study. The children were examined for dental fluorosis according to the Thylstrup-Fejerskov Index (TFI). The children and their mothers were subsequently interviewed. Sixty mothers had more than one participating child. In order to perform a paired parent/child analysis, a total of 73 younger siblings had to be excluded. Among the remaining 233 children, the prevalence of severe dental fluorosis (TFI >or= 5) was 24.1% and 75.9% in the moderate- and high-fluoride areas, respectively. According to bivariate as well as multivariate analyses, a number of sociodemographic and behavioural factors were related to severe fluorosis. The odds for having severe fluorosis varied according to the fluoride concentration of the drinking water, age, consumption of tea, length of breastfeeding and method of storing water. The adjusted odds ratios ranged from 2.6 to 26.1. Breastfeeding for > 18 months and the use of clay pots for storing drinking water helped protect against severe dental fluorosis. Bivariate analyses indicated that being male and consuming fish might be associated with higher TFI scores. In order to avoid dental fluorosis, low-fluoride drinking water should be provided in the relevant villages. A prolonged period of breastfeeding, the use of clay pots for storing water, and possibly a reduced intake of tea and whole fish in infants might also help to avoid severe fluorosis in children growing up in traditionally fluoride-endemic areas.

  14. Molecular mechanisms of fluoride toxicity.

    Science.gov (United States)

    Barbier, Olivier; Arreola-Mendoza, Laura; Del Razo, Luz María

    2010-11-05

    Halfway through the twentieth century, fluoride piqued the interest of toxicologists due to its deleterious effects at high concentrations in human populations suffering from fluorosis and in in vivo experimental models. Until the 1990s, the toxicity of fluoride was largely ignored due to its "good reputation" for preventing caries via topical application and in dental toothpastes. However, in the last decade, interest in its undesirable effects has resurfaced due to the awareness that this element interacts with cellular systems even at low doses. In recent years, several investigations demonstrated that fluoride can induce oxidative stress and modulate intracellular redox homeostasis, lipid peroxidation and protein carbonyl content, as well as alter gene expression and cause apoptosis. Genes modulated by fluoride include those related to the stress response, metabolic enzymes, the cell cycle, cell-cell communications and signal transduction. The primary purpose of this review is to examine recent findings from our group and others that focus on the molecular mechanisms of the action of inorganic fluoride in several cellular processes with respect to potential physiological and toxicological implications. This review presents an overview of the current research on the molecular aspects of fluoride exposure with emphasis on biological targets and their possible mechanisms of involvement in fluoride cytotoxicity. The goal of this review is to enhance understanding of the mechanisms by which fluoride affects cells, with an emphasis on tissue-specific events in humans. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

  15. Anthropogenic materials and products containing natural radionuclides. Pt. 2. Examination of radiation doses resulting from occupational exposure

    International Nuclear Information System (INIS)

    Reichelt, A.; Lehmann, K.H.

    1993-11-01

    The radiation doses are determined on the basis of dosimetric scanning of the materials and products and measurement of the ambient dose rates and inhaled doses at the place of work. For all places and conditions exmined, the average annual effective dose (ICRP) is of the order of 20mSv/annum. The substances and products examined are phosphate fertilizers. thoriated tungsten electrodes, or glass gas hoods, respectively, dental material containing uranium, and dental ceramics containing zirconium sands. The report also gives information on the occupational exposure in drinking-water conditioning plants. (Orig./DG) [de

  16. Processing fissile material mixtures containing zirconium and/or carbon

    Science.gov (United States)

    Johnson, Michael Ernest; Maloney, Martin David

    2013-07-02

    A method of processing spent TRIZO-coated nuclear fuel may include adding fluoride to complex zirconium present in a dissolved TRIZO-coated fuel. Complexing the zirconium with fluoride may reduce or eliminate the potential for zirconium to interfere with the extraction of uranium and/or transuranics from fission materials in the spent nuclear fuel.

  17. Measuring quality of dental care: Caries prevention services for children.

    Science.gov (United States)

    Herndon, Jill Boylston; Tomar, Scott L; Catalanotto, Frank A; Rudner, Nancy; Huang, I-Chan; Aravamudhan, Krishna; Shenkman, Elizabeth A; Crall, James J

    2015-08-01

    The authors conducted a study to validate the following 3 evidence-based, process-of-care quality measures focused on dental caries prevention for children with an elevated risk of experiencing caries: sealants for 6- to 9-year-olds, sealants for 10- to 14-year-olds, and topical fluoride. Using evidence-based guidelines, the Dental Quality Alliance developed measures for implementation with administrative data at the plan and program levels. To validate the measures, the authors used data from the Florida and Texas Medicaid programs and Children's Health Insurance Programs and from national commercial dental benefit plans. Data were extracted from 414 randomly selected dental office records to validate the use of administrative data to accurately calculate the measures. The authors also assessed statistically significant variations in overall measure performance. Agreement between administrative data and dental records was 95% for sealants (κ = 0.82) and 90% for topical fluoride (κ = 0.78). Sensitivity and specificity were 90.7% and 88.5% for topical fluoride and 77.8% and 98.8% for sealants, respectively. Variation in overall measure performance was greatest for topical fluoride (χ(2) = 5,887.1; P caries received at least 2 topical fluoride applications during the reporting year. Although there was greater variation in performance for sealants for 6- to 9-year-olds (range, 21.0-31.3%; χ(2) = 548.6; P caries prevention process-of-care quality measures can be implemented feasibly and validly using administrative claims data. The measures can be used to assess, monitor, and improve the proportion of children with an elevated risk of experiencing dental caries who receive evidence-based caries prevention services. Copyright © 2015 American Dental Association. Published by Elsevier Inc. All rights reserved.

  18. A Survey of Fluoride Dosage in Driniking Water and DMF Index in Damghan City

    Directory of Open Access Journals (Sweden)

    Hamid Reza Nasehi nia

    2004-05-01

    Full Text Available Fluoride is one of the important elements. There are so many controversial scientific points of view regarding fluoride and its presence in food chain. Water fluoridation is the best and most reliable method for the control of dental caries. In this research, the presence and concentration of fluoride in drinking water resources in the city of Damghan and DMF index (decayed, missed, filled between 560 school students (12-15 was investigated. The mean concentration of fluoride in water supplies of Damaghan city was measured in low rain seasons 0.37 mg/l and high rain seasons 0.6 mg/l the DMF index for 12 year sold student was equal 2.00 that comparing these data with the WHO classify cation for DMF index, showed them to be considered in the second surface (low classificatino. For conclusion, based on the mentioned data, a significant correlation may be found between the two parameters in different communities, and the most logic solution for the control of dental cavities in these communities, is the adjusment of fluoride concentration in drinking water.

  19. Anodic polarization of carbon graphite electrodes in chloride fluoride melts zirconium containing

    International Nuclear Information System (INIS)

    Lyapustin, A.A.; Kanashin, Yu.P.; Nichkov, I.F.; Smyshlyaev, V.Yu.

    1985-01-01

    Polarization of carbon graphite anodes in zircorium containing chloride fluoride melts of the KCl-K 2 ZrF 6 -KF composition at molar ratios [F]:[Zr] being equal to 6, 12, 18, 24, 30 has been studied. K 2 ZrF 6 concentration constitutes 25; 18.9; 15.2; 12.7; 11.8% (by mass), correspondingly. Vitreous carbon (VC-2500), high purity graphite and graphite EhG-0 have been used as anodic materials. Anodic polarization curves have been obtained under electrotype steady-state conditions at 973, 1023, 1073 K. Influence of concentration of fluorine ions in melt on polarization of carbon graphite anodes is shown. Content growth of fluorine ions in melt leads to shift of steady-state anode potentials to their negative values regardless a graphite mark. The most con siderable potential shift on 0.5 V takes plase at molar ratio [F]:[Zr] increasing from 6 to 12. Temperature increase, as measurements showed, doesn't influence greatly on polarization curve shape

  20. Fluoride in diet

    Science.gov (United States)

    Diet - fluoride ... bones and teeth. Too much fluoride in the diet is very rare. Rarely, infants who get too ... of essential vitamins is to eat a balanced diet that contains a variety of foods from the ...

  1. An assessment of dental anxiety in nonclinical setting among Saudi Arabian children using Abeer Children Dental Anxiety Scale

    Directory of Open Access Journals (Sweden)

    Shabina Shafi

    2015-01-01

    Full Text Available Introduction: Dental anxiety is an abnormal fear or dread of visiting the dentist for preventive care or therapy and unwarranted anxiety over dental procedures. It is a common problem that affects people of all ages and appears to develop mostly in childhood and adolescence. The present study assesses dental anxiety among children in a nonclinical setting among Saudi Arabian children who underwent preventive treatment procedure using Abeer Children Dental Anxiety Scale (ACDAS. Materials and Methods: The children attending an oral health program were screened for oral health problems and preventive treatment such as topical fluoride applications. The dental anxiety among children was assessed using ACDAS. Results: A total of 51 children participated in the research. The results showed that maximum children were not scared of dentist in nonclinical setting and had low dental anxiety levels. Overall, 74% of the child subjects had ACDAS scores below 26. Conclusions: Knowing the degree of anxiety of dental children is important to guide them through their dental experience and carry on the preventive dental treatments at an early age in nonclinical setting. Their level of cooperation will improve, and anxiety will be reduced as well. Further research is required to compare dental anxiety levels in children between clinical and nonclinical setting.

  2. SITUATION OF FLUORIDES RATE IN WATERS AND MAJOR ...

    African Journals Online (AJOL)

    31 déc. 2010 ... by fluoride ions in the waters of the region (Fluorosis Dental and skeletal). This study proposes, the estimated daily intake of fluoride from its water .... Le fluor est dosé par la méthode potentiométrique (NF T 90-004) grâce à une électrode spécifique aux ions fluorures. La mesure du potentiel a été effectuée ...

  3. Influence of resin-modified glass ionomer and topical fluoride on levels of Streptococcus mutans in saliva and biofilm adjacent to metallic brackets

    Directory of Open Access Journals (Sweden)

    Marcela Cristina Damião ANDRUCIOLI

    Full Text Available Abstract Decalcification of enamel during fixed orthodontic appliance treatment remains a problem. White spot lesions are observed in nearly 50% of patients undergoing orthodontic treatment. The use of fluoride-containing orthodontic materials has shown inconclusive results on their ability to reduce decalcification. The aims of this investigation were to compare the levels of Streptococcus mutans (SM in saliva and biofilm adjacent to orthodontic brackets retained with a resin-modified glass ionomer cement (RMGIC (Fuji ORTHO LC and a light cured composite resin (Transbond XT, and to analyze the influence of topical application of the 1.23% acidulated phosphate fluoride (APF on SM counts. In a parallel study design, two groups (n=14/15 were used with random allocation and high salivary SM counts before treatment. Biofilm was collected from areas adjacent to the brackets on teeth 13, 22, 33, and 41. Both saliva and biofilm were collected on the 7th, 21st, 35th, and 49th days after appliance placement. Topical fluoride application was carried out on the 35th day. Bonding with RMGIC did not alter SM counts in saliva or biofilm adjacent to the brackets. On the other hand, the biofilm adjacent to brackets retained with composite resin showed a significant increase in SM counts along the trial period. Topical application of 1.23% APF did not reduce salivary or biofilm SM counts regardless of the bonding material. In conclusion, fluoride topical application did not show efficacy in reducing SM. The use of RMGIC as bonding materials allowed a better control of SM cfu counts in dental biofilm hindering the significant increase of these microorganisms along the trial period, which was observed in the biofilm adjacent to the composite material.

  4. A review of the prevalence of dental fluorosis in Mexico Revisión de la prevalencia de fluorosis dental en México

    Directory of Open Access Journals (Sweden)

    Armando Ernesto Soto-Rojas

    2004-01-01

    Full Text Available OBJECTIVE: There has been a worrisome increase in the prevalence of dental fluorosis worldwide. The objective of this study was to review research on dental fluorosis prevalence in Mexico in order to assess if that prevalence is rising and if dental fluorosis constitutes a public health problem for the country. METHODS: Clinical, experimental, and review reports were searched for in a number of bibliographic databases for scientific literature, using the search phrase "fluorosis and Mexico." All the materials that were initially identified had to satisfy eight specific criteria in order to be included in our study. RESULTS: Of the 24 publications that the literature search yielded, 14 satisfied all the inclusion criteria. The prevalence of dental fluorosis reported in Mexico ranged from 30% to 100% in areas where water is naturally fluoridated and from 52% to 82% in areas where fluoridated salt is used. Most of the 14 studies were conducted in areas where water fluoride levels were above optimal, and the fluorosis cases reported in these publications ranged from "mild" to "severe." There have been only a small number of reports on dental fluorosis since the introduction of fluoridated salt in the country in 1991. However, some of those studies have shown that the prevalence of fluorosis was higher than what would be expected given the historical data from communities with optimal fluoridation in other countries. CONCLUSION: Due to the limited amount of information, it is not possible to determine if the prevalence of dental fluorosis in Mexico is rising or if it constitutes a public health problem. To objectively answer these questions more controlled studies are needed in areas where fluoridated salt is distributed, where water fluoride is above optimal, and where residents live at a high altitude.OBJETIVOS: La prevalencia de fluorosis dental ha aumentado de forma alarmante en todo el mundo. El objetivo de este estudio fue analizar las

  5. Hawaii's epidemic dental decay rate in children.

    Science.gov (United States)

    Sueda, Stacie T

    2008-01-01

    The purpose of this study was to determine if other factors besides community water fluoridation influences the dental decay rate in children. Identical questionnaires were filled out by two groups of parents, both with a sample size of 100, whose healthy children (ages 5-12) were patients of a pediatric dentist practicing in a non-fluoridated water community. Group A had children with zero Decay or Filled Teeth (DFT). Group B had children with at least five DFT. Children were found to have a significantly lower dental decay rate (P disciplining them; 7) the child was are not "strong-willed" or "hard-headed;" 8) someone does not appease (or "give in" to) them when they get upset; 9) they do not live in a single parent household; and 10) at least one parent achieves a higher academic educational level. This study suggests that water fluoridation is not the only way to prevent dental decay.

  6. The efficacy of amine fluoride/stannous fluoride in the suppression of morning breath odour.

    Science.gov (United States)

    Quirynen, Marc; Avontroodt, Pieter; Soers, Catherine; Zhao, Hong; Pauwels, Martine; Coucke, Wim; van Steenberghe, Daniel

    2002-10-01

    Breath odour is a complaint encountered worldwide, often linked to microbial overload in the oral cavity. This double blind, crossover, randomised study assessed the efficacy of several antiseptic mouthrinses or slurry vs. a control solution in the prevention of morning bad breath during an experimental period of 7 days without mechanical plaque control. Sixteen dental students with a healthy periodontium abolished, after a thorough professional cleaning, all means of mechanical plaque control during five experimental periods of 7 days, interleaved by washout periods of at least 3 weeks. During each experimental period, as the only oral hygiene measure, the students rinsed twice a day with one of the following formulations (in a randomised order): a 0.2% chlorhexidine-alcohol mouthrinse (CHX-Alc), a 0.05% CHX + 0.05% cetylpyridinium chloride + 0.14% zinc lactate mouthrinse (CHX-CPC-Zn), an amine fluoride/stannous fluoride (125 ppm F-/125 ppm F-) containing mouthrinse (AmF/SnF2Mr), a slurry of a tooth paste (AmF/SnF2Sl) containing amine fluoride (350 ppm F-) and stannous fluoride (1050 ppm F-) and a placebo solution (placebo). At days 0, 3 and 7, morning breath was scored via VSC level measurements of the mouth air, and organoleptic ratings of the mouth air and tongue coating. At the same visits both the degree of gingival inflammation and the de novo plaque formation were rated. At the end of each period a questionnaire for subjective ratings was completed and microbiological samples were taken from the tongue dorsum, the saliva and the supragingival plaque for anaerobic and aerobic culturing. Although oral hygiene during the experimental periods was limited to rinsing, bad breath parameters systematically improved (P bacterial load (aerobic & anaerobic) in the saliva (>or= 0.5 log reduction with a superiority (P bacterial load on the tongue dorsum could only be detected for the CHX-Alc solution (0.5 log). The antibacterial effect of the placebo solution and the

  7. Erosion-inhibiting effect of sodium fluoride and titanium tetrafluoride treatment in vitro

    NARCIS (Netherlands)

    Rijkom, Hans van; Ruben, J.; Vieira, A.; Huysmans, M.C.; Truin, G-J.; Mulder, J.

    2003-01-01

    The prevention of dental erosion with fluoride is still largely unknown territory. It was the aim of this study to determine the erosion-inhibiting effect of topical neutral 1% sodium fluoride (NaF) application and an application of a 4% titanium tetrafluoride (TiF4) solution compared with no

  8. Impact of Dental Fluorosis, Socioeconomic Status and Self-Perception in Adolescents Exposed to a High Level of Fluoride in Water.

    Science.gov (United States)

    Molina-Frechero, Nelly; Nevarez-Rascón, Martina; Nevarez-Rascón, Alfredo; González-González, Rogelio; Irigoyen-Camacho, María Esther; Sánchez-Pérez, Leonor; López-Verdin, Sandra; Bologna-Molina, Ronell

    2017-01-12

    Objective : To identify adolescents' self-perception of dental fluorosis from two areas with different socioeconomic levels. Methods : A cross-sectional, descriptive study was conducted with 15-year-old youths by applying a questionnaire designed and validated to assess self-perceptions of dental fluorosis in two areas with different socioeconomic statuses (SESs). Fluorosis was clinically evaluated by applying the Thylstrup and Fejerkov (TF) index on the upper front teeth. Results : A total of 308 adolescents were included in the study. The medium-SES population, which was exposed to 2.5 ppm of fluoride in water, and the low-SES population, which was exposed to 5.1 ppm, presented the following levels of dental fluorosis: TF 2-3 (50%), TF 4-5 (45.6%) and TF 6-7 (4.4%) for medium SES and TF 2-3 (12.3%), TF 4-5 (67.1%) and TF 67 (20.6%) for low SES. A significant association was found between self-perception and dental fluorosis in those with medium and low SESs ( p self-perception, with a 6-7 TF level for concerns about color (OR = 1.6), smile (OR = 1.2) and appearance (OR = 3.36). Conclusions : Self-perceptions of dental fluorosis affect adolescents such that adolescents with a medium SES have more negative perceptions than those with a low SES. Such perceptions increase as the TF index increases.

  9. Effects of the fluoride on the central nervous system.

    Science.gov (United States)

    Valdez-Jiménez, L; Soria Fregozo, C; Miranda Beltrán, M L; Gutiérrez Coronado, O; Pérez Vega, M I

    2011-06-01

    Fluoride (F) is a toxic and reactive element, and exposure to it passes almost unnoticed, with the consumption of tea, fish, meat, fruits, etcetera and articles of common use such as: toothpaste additives; dental gels, non-stick pans and razor blades as Teflon. It has also been used with the intention of reducing the dental cares. Fluoride can accumulate in the body, and it has been shown that continuous exposure to it causes damaging effects on body tissues, particularly the nervous system directly without any previous physical malformations. Several clinical and experimental studies have reported that the F induces changes in cerebral morphology and biochemistry that affect the neurological development of individuals as well as cognitive processes, such as learning and memory. F can be toxic by ingesting one part per million (ppm), and the effects they are not immediate, as they can take 20 years or more to become evident. The prolonged ingestion of F may cause significant damage to health and particularly to the nervous system. Therefore, it is important to be aware of this serious problem and avoid the use of toothpaste and items that contain F, particularly in children as they are more susceptible to the toxic effects of F. Copyright © 2010 Sociedad Española de Neurología. Published by Elsevier Espana. All rights reserved.

  10. Evaluation of exposure to fluoride in child population of North Argentina.

    Science.gov (United States)

    Rocha, René Antonio; Calatayud, Marta; Devesa, Vicenta; Vélez, Dinoraz

    2017-09-01

    Fluoride is an important element for humans. It inhibits initiation and progression of dental caries and stimulates bone formation. However, excessive intake may lead to the appearance of dental and/or skeletal fluorosis and a decrease in intellectual coefficient in child populations. This study evaluates exposure to fluoride in the child population of Chaco province (Argentina) by analysis of drinking water, food and its bioaccessible fraction (quantity of fluoride solubilised by gastrointestinal digestion and available for intestinal absorption) and urine as a biomarker of internal dose. The concentration of fluoride in drinking water varied between 0.050 and 4.6 mg L -1 , and 80% of the samples exceeded the WHO drinking-water guideline value (1.5 mg L -1 ). Fluoride concentrations in food ranged between 0.80 and 3.0 mg kg -1 fresh weight (fw), being lower in bioaccessible fraction (0.43-1.9 mg kg -1 , fw). On the basis of the consumption data declared for the young child population, fluoride intake varies between 4.1 and 6.5 mg day -1 , greater than the level recommended for this age group. Moreover, in some cases, concentrations of fluoride found in urine (0.62-8.9 mg L -1 ) exceeded those reported in areas with declared fluorosis. All data obtained show the worrying situation of child population in this area of Argentina.

  11. Prevalence of enamel defects and MIH in non-fluoridated and fluoridated communities.

    Science.gov (United States)

    Balmer, R C; Laskey, D; Mahoney, E; Toumba, K J

    2005-12-01

    This was to study the prevalence of enamel defects and molar incisor hypomineralisation (MIH) in children attending Leeds Dental Institute (UK) and Westmead Dental Hospital, Sydney (Australia). Prospective dental examinations were carried out on 25 children referred to two orthodontic departments. A questionnaire was completed to obtain background information and about previous fluoride (F) exposure followed by an oral examination. First permanent molars and permanent incisors were examined for presence, type and severity of enamel defects using the modified DDE screening index. Chi square tests were used to compare results. Data for 24 children in Sydney and 20 in Leeds presented with at least one enamel defect. Of 300 teeth examined, 155 in Sydney and 82 in Leeds had a defect (p MIH was the same supporting the view that F is not associated with the aetiology of MIH.

  12. Fluoride-associated ultrastructural changes and apoptosis in human renal tubule: a pilot study.

    Science.gov (United States)

    Quadri, J A; Sarwar, S; Sinha, A; Kalaivani, M; Dinda, A K; Bagga, A; Roy, T S; Das, T K; Shariff, A

    2018-01-01

    The susceptibility of the kidneys to fluoride toxicity can largely be attributed to its anatomy and function. As the filtrate moves along the complex tubular structure of each nephron, it is concentrated in the proximal and distal tubules and collecting duct. It has been frequently observed that the children suffering from renal impairments also have some symptoms of dental and skeletal fluorosis. The findings suggest that fluoride somehow interferes with renal anatomy and physiology, which may lead to renal pathogenesis. The aim of this study was to evaluate the fluoride-associated nephrotoxicity. A total of 156 patients with childhood nephrotic syndrome were screened and it was observed that 32 of them had significantly high levels ( p ≤ 0.05) of fluoride in urine (4.01 ± 1.83 ppm) and serum (0.1 ± 0.013 ppm). On the basis of urinary fluoride concentration, patients were divided into two groups, namely group 1 (G-1) ( n = 32) containing normal urine fluoride (0.61 ± 0.17 ppm) and group 2 (G-2) ( n = 32) having high urine fluoride concentration (4.01 ± 1.83 ppm). Age-matched healthy subjects ( n = 33) having normal levels of urinary fluoride (0.56 ± 0.15 ppm) were included in the study as control (group 0 (G-0)). Kidney biopsies were taken from G-1 and G-2 only, who were subjected to ultrastructural (transmission electron microscopy) and apoptotic (terminal deoxynucleotidyl transferase deoxyuridine triphosphate nick end labeling) analysis. Various subcellular ultrastructural changes including nuclear disintegration, chromosome condensation, cytoplasmic ground substance lysis, and endoplasmic reticulum blebbing were observed. Increased levels of apoptosis were observed in high fluoride group (G-2) compared to normal fluoride group (G-1). Various degrees of fluoride-associated damages to the architecture of tubular epithelia, such as cell swelling and lysis, cytoplasmic vacuolation, nuclear condensation, apoptosis, and necrosis, were observed.

  13. Low-levels of fluoride in plaque and saliva and their effects on the demineralisation and remineralisation of enamel; role of fluoride toothpastes.

    Science.gov (United States)

    Lynch, R J M; Navada, R; Walia, R

    2004-01-01

    To summarise support for current consensus on the likely means by which fluoride toothpastes reduce caries and review some relevant studies of the effect of low levels of fluoride on the demineralisation and remineralisation of enamel. The major anti-caries effect of fluoride toothpastes is thought to result from small but protracted elevations in levels of fluoride in plaque and saliva. Fluoride incorporated into enamel systemically does not reduce enamel solubility sufficiently to exert an anti-caries effect. Fluoride has the potential to exert an anti-caries benefit largely through three mechanisms; inhibition of demineralisation, promotion of remineralisation and interference with bacterial growth and metabolism. However, the low levels of fluoride thought to influence caries are insufficient to have a significant effect via the latter mechanism. Thus reductions in caries resulting from the use of fluoride toothpastes can be linked to modification of the demineralisation/remineralisation balance by direct effects on dental mineral exerted topically by low levels of fluoride. Numerous in vitro studies have shown that low levels of fluoride, typical of those found after many hours in resting plaque and saliva, and resulting from the regular use of fluoride toothpastes, can have a profound effect on enamel demineralisation and remineralisation.

  14. Prevalence of Dental Fluorosis Among 6–12-Year-Old School Children of Mahabubnagar District, Telangana State, India − A Cross-Sectional Study

    Directory of Open Access Journals (Sweden)

    Kola S Reddy

    2017-01-01

    Full Text Available Introduction: Telangana state in southern India has many areas which have high–low fluoride levels in drinking water, and Mahabubnagar district is one among them, where people are affected with dental and skeletal fluorosis, with the majority belonging to low socio-economic status. Aims: To assess the prevalence of dental fluorosis in school going children of Mahabubnagar district and also to assess fluoride levels in drinking water from different areas of Mahabubnagar district. Materials and Methods: A cross-sectional study was conducted on 2000 children in the age group 6–12 years in different areas of Mahabubnagar district. Dental fluorosis status was assessed by using Modified Dean’s Fluorosis Index. Alizarin visual method was used to estimate fluoride levels in water. The data collected were subjected to statistical analysis. Results: Dental fluorosis in primary and permanent dentition was 15 and 70.3%, respectively. In the northern part of Mahabubnagar district, primary dentition was more affected by fluorosis whereas in southern part, the permanent dentition was more affected. The prevalence of dental fluorosis in primary dentition was more in 6–7-year-old children (35.5%, and in permanent dentition, it was more in 9–10-year-old children (70%. The fluoride level in drinking water was more in Kosghi, Kalwakurthy (2.0 ppm. Conclusion: Dental fluorosis was more in 10-year-old and less in 6-year-old children. It was more in eastern and northern zones of Mahabubnagar district and less in local villages of Mahabubnagar.

  15. Determination of dose rate from natural radionuclide in porcelain dental materials

    International Nuclear Information System (INIS)

    Nouri, A.D.; El-Zourgany, A.; Elmashat, Alia; El-Masri, Karima

    2010-01-01

    There are three main aims that make this study particularly important and interesting to radiometric studies. Firstly, it will provides information on the concentration composition of natural and the associated man-made radioactivity of imported dental porcelain materials to be used by most dental laboratories in Great Jamahiriya. Since these materials do not pass radiation inspection tests before their entry or use and there is a large variety of supply source of these dental materials to be used for all dental works on Libyan patients, anomalies can be identified easily. Secondly, the analysis of selective elemental abundance (U, Th, and K ) and dose rate calculations may be used to calculate effective dose rates to dental laboratory technicians and also to the patient who will be using these specific materials. This research project will provide the first results of such measurements and the corresponding average annual effective dose rates equivalent to the patients using these materials and also to the dental technician and doctors work in the various dental laboratories that make use of these materials in their daily work. A total number of 30 dental powder samples were collected from a number of dental laboratories around Tripoli area will be analyzed. In this research project, the results from this preliminary survey regarding Th, U and K elemental concentrations in a wide variety of dental materials by means of high-resolution X-ray spectrometry will be presented. Further results from these investigations concerning activity concentrations and the associated dose rates, effective dose and the committed dose due to the use of these materials are going to be calculated and compared with other published data elsewhere and recommendation of their use will be derived accordingly. (author)

  16. Silver diamine fluoride: a caries "silver-fluoride bullet".

    Science.gov (United States)

    Rosenblatt, A; Stamford, T C M; Niederman, R

    2009-02-01

    The antimicrobial use of silver compounds pivots on the 100-year-old application of silver nitrate, silver foil, and silver sutures for the prevention and treatment of ocular, surgical, and dental infections. Ag(+) kills pathogenic organisms at concentrations of linings, water purification systems, hospital gowns, and caries prevention. To distill the current best evidence relative to caries, this systematic review asked: Will silver diamine fluoride (SDF) more effectively prevent caries than fluoride varnish? A five-database search, reference review, and hand search identified 99 human clinical trials in three languages published between 1966 and 2006. Dual review for controlled clinical trials with the patient as the unit of observation, and excluding cross-sectional, animal, in vitro studies, and opinions, identified 2 studies meeting the inclusion criteria. The trials indicated that SDF's lowest prevented fractions for caries arrest and caries prevention were 96.1% and 70.3%, respectively. In contrast, fluoride varnish's highest prevented fractions for caries arrest and caries prevention were 21.3% and 55.7%, respectively. Similarly, SDF's highest numbers needed to treat for caries arrest and caries prevention were 0.8 (95% CI=0.5-1.0) and 0.9 (95% CI=0.4-1.1), respectively. For fluoride varnish, the lowest numbers needed to treat for caries arrest and prevention were 3.7 (95% CI=3.4-3.9) and 1.1 (95% CI=0.7-1.4), respectively. Adverse events were monitored, with no significant differences between control and experimental groups. These promising results suggest that SDF is more effective than fluoride varnish, and may be a valuable caries-preventive intervention. As well, the availability of a safe, effective, efficient, and equitable caries-preventive agent appears to meet the criteria of both the WHO Millennium Goals and the US Institute of Medicine's criteria for 21st century medical care.

  17. Dental fluorosis knowleDge anD perception among stuDents of the ...

    African Journals Online (AJOL)

    Newbrun, E. Fluoride and Dental caries (3 ed.). San francisco: Springfield. 1978. 5.Vuhahula et al. Dental fluorosis in Great Rift Valley in relation to fluoride level in water and Magadi. Desalination. 2010; 252: 193-198. 3. Group students who didn't know how fluorosis can be avoided students who knew how fluorosis can be.

  18. Modeling an economic evaluation of a salt fluoridation program in Peru.

    Science.gov (United States)

    Mariño, Rodrigo J; Fajardo, Jorge; Arana, Ana; Garcia, Carlos; Pachas, Flor

    2011-01-01

    This article models the cost-effectiveness, from a societal viewpoint, of a dental caries prevention program using salt fluoridation for children 12 years of age, compared with non-intervention (or status quo) in Arequipa, Peru. Standard cost-effectiveness analysis methods were used. The costs associated with implementing and operating the salt-fluoridation program were identified and measured using 2009 prices. Health outcomes were measured as dental caries averted over a 6-year period. Clinical effectiveness data was taken from published data. Costs were measured as direct treatment costs, programs costs and costs of productivity losses as a result of dental treatments. The incremental cost-effectiveness ratio was calculated. A hypothetical population of 25,000 12-year-olds living in Arequipa, Peru was used in this analysis. Two-way sensitivity analyses were conducted over a range of values for key parameters. Our primary analysis estimated that if a dental caries prevention program using salt-fluoridation was available for 25,000 6-year-old children for 6 years, the net saving from a societal perspective would total S/. 11.95 [1 US$ = S/. (2009) 3.01] per diseased tooth averted when compared with the status quo group. That is, after 6 years, an investment of S/.0.32 per annum per child would result in a net saving of S/.11.95 per decayed/missing/filled teeth prevented. While the analysis has inherent limitations as a result of its reliance on a range of assumptions, the findings indicate that for the situations prevailing in Peru, there are significant health and economic benefits to be gained from the use of salt fluoridation.

  19. Oral fluoride levels 1 h after use of a sodium fluoride rinse: effect of sodium lauryl sulfate.

    Science.gov (United States)

    Vogel, Gerald L; Schumacher, Gary E; Chow, Laurence C; Tenuta, Livia M A

    2015-01-01

    Increasing the concentration of free fluoride in oral fluids is an important goal in the use of topical fluoride agents. Although sodium lauryl sulfate (SLS) is a common dentifrice ingredient, the influence of this ion on plaque fluid and salivary fluid fluoride has not been examined. The purpose of this study was to investigate the effect of SLS on these parameters and to examine the effect of this ion on total (or whole) plaque fluoride, an important source of plaque fluid fluoride after a sufficient interval following fluoride administration, and on total salivary fluoride, a parameter often used as a surrogate measure of salivary fluid fluoride. Ten subjects accumulated plaque for 48 h before rinsing with a 12 mmol/l NaF (228 µg/g F) rinse containing or not containing 0.5% (w/w) SLS. SLS had no statistically significant effect on total plaque and total saliva fluoride but significantly increased salivary fluid and plaque fluid fluoride (by 147 and 205%, respectively). These results suggest that the nonfluoride components of topical agents can be manipulated to improve the fluoride release characteristics from oral fluoride reservoirs and that statistically significant change may be observed in plaque fluid and salivary fluid fluoride concentrations that may not be observed in total plaque and total saliva fluoride concentrations.

  20. Profile of Fluoride Release from a Nanohybrid Composite Resin

    Directory of Open Access Journals (Sweden)

    Raquel Assed Bezerra Silva

    2015-02-01

    Full Text Available The aim of this study was to evaluate in vitro the amount and profile of fluoride release from a fluoride-containing nanohybrid composite resin (Tetric® N-Ceram by direct potentiometry. Thirty specimens (5 mm diameter x 3 mm high; n=10/material were made of Tetric® N-Ceram, Vitremer® resin-modified glass ionomer cement (RMGIC (positive control or Filtek® Z350 nanofill composite resin (negative control. The specimens were stored individually in plastic tubes containing 1 mL of artificial saliva at 37°C, which was daily renewed during 15 days. At each renewal of saliva, the amount of fluoride ions released in the solution was measured using a fluoride ion-selective electrode with ion analyzer, and the values obtained in mV were converted to ppm (µg/mL. Data were analyzed statistically by ANOVA and Tukey’s post-hoc test at a significance level of 5%. The results showed that the resins Tetric® N-Ceram and Filtek® Z350 did not release significant amounts of fluoride during the whole period of evaluation (p>0.05. Only Vitremer® released significant amounts of fluoride ions during the 15 days of the experiment, with greater release in first 2 days (p0.05. In conclusion, the nanohybrid composite resin Tetric® N-Ceram did not present in vitro fluoride-releasing capacity throughout the 15 days of study.

  1. Fluoride Concentration in Water, Cow Milk and Cow Urine from Smallholder Dairy Farms in Kiambu- Kenya

    International Nuclear Information System (INIS)

    Gikunju, J.K.; Maitho, T.E.; Kyule, M.N.; Mitema, E.S.; Mugera, G.M.

    1999-01-01

    Kiambu district is situated in central part of Kenya. most of the available land is suitable for agricultural use. majority of the farmers are small scale or subsistence farmers and they are involve in a variety of livestock activities e.g. dairy production, pig production and others in combination or as separate operations. excessive fluoride ingestion can cause specific dental and skeletal lesions and in severe cases adversely influence the health and productivity performance of domestic animals.therefore a study was designed to investigate the levels of flouride in urine, milk and water samples from small scale dairy farms in Kiambu. Water, cow urine and milk samples were collected in clean plastic containers from 84 small scale farms belonging to 6 dairy farmers co-operative societies (DFCs). The DFCs in this study were Kiambaa, Lari, Nderi, Kikuyu, Chania and Limuru. The fluoride concentration in water milk and urine were analysed using the potentiometric method of fluoride ion specific electrode. overall urine contained the highest fluoride concentration while milk contained the lowest fluoride levels. Fluoride levels in water, milk and urine were significantly different, (P>0.05). The mean fluoride concentration in water from all societies was 0.29 ppm while the mean fluoride concentration in milk 0.05 ppm. urine samples had the highest fluoride concentration, (1.5 ppm). The cooperative specific mean fluoride concentrations arranged in descending order were as follow: Nderi (2.8 ppm), Kikuyu (2.4 ppm), Kiambaa(1.9 ppm), Chania (1.6 ppm), Limuru (1.3 ppm) and Lari (1.0 ppm). The maximum fluoride concentration encountered in water in this study was 3.4 ppm, however adverse productivity has been reported in dairy animals consuming as low as 2.15 ppm in drinking water. The mean milk production in in kilograms per day per cow ranged from 2.5 to 6.9 when all six dairy co-operative societies were taken into consideration. this is far below the expected production

  2. Antimicrobial activity of fluoride and its in vivo importance: identification of research questions.

    Science.gov (United States)

    Van Loveren, C

    2001-01-01

    This manuscript discusses the antimicrobial activity of fluoride and its in vivo importance in order to identify research questions. There is a lot of information on mechanisms by which fluoride may interfere with bacterial metabolism and dental plaque acidogenicity. The antimicrobial activity of fluoride products is enhanced when fluoride is associated with antimicrobial cations like Sn(2+) and amine. It is not clear whether the antimicrobial mechanisms of fluoride are operating in vivo or even to what extent antimicrobial activity can contribute to caries prevention. This latter question may be the most important one in research. Copyright 2001 S. Karger AG, Basel.

  3. The electrochemical performance and mechanism of cobalt (II) fluoride as anode material for lithium and sodium ion batteries

    International Nuclear Information System (INIS)

    Tan, Jinli; Liu, Li; Guo, Shengping; Hu, Hai; Yan, Zichao; Zhou, Qian; Huang, Zhifeng; Shu, Hongbo; Yang, Xiukang; Wang, Xianyou

    2015-01-01

    Highlights: •The as-prepared CoF 2 shows excellent electrochemical performance as anode material for lithium ion batteries. •The Li insertion/extraction mechanism of CoF 2 below 1.2 V was firstly proposed. •The electrochemical performance of CoF 2 as anode material in sodium ion batteries was firstly studied. -- Abstract: Cobalt (II) fluoride begins to enter into the horizons of people along with the research upsurge of metal fluorides. It is very significative and theoretically influential to make certain its electrochemical reaction mechanism. In this work, we discover a new and unrevealed reversible interfacial intercalation mechanism reacting below 1.2 V for cobalt (II) fluoride electrode material, which contributes a combined discharge capacity of about 400 mA h g −1 with the formation of SEI film at the initial discharge process. A highly reversible storage capacity of 120 mA h g −1 is observed when the cell is cycled over the voltage of 0.01-1.2 V at 0.2 C, and the low-potential voltage reaction process has a significant impact for the whole electrochemical process. Electrochemical analyses suggest that pure cobalt (II) fluoride shows better electrochemical performance when it is cycled at 3.2-0.01 V compared to the high range (1.0-4.5 V). So, we hold that cobalt (II) fluoride is more suitable to serve as anode material for lithium ion batteries. In addition, we also try to reveal the relevant performance and reaction mechanism, and realize the possibility of cobalt (II) fluoride as anode material for sodium ion batteries

  4. Hydrogeochemistry and statistical analysis applied to understand fluoride provenance in the Guarani Aquifer System, Southern Brazil.

    Science.gov (United States)

    Marimon, Maria Paula C; Roisenberg, Ari; Suhogusoff, Alexandra V; Viero, Antonio Pedro

    2013-06-01

    High fluoride concentrations (up to 11 mg/L) have been reported in the groundwater of the Guarani Aquifer System (Santa Maria Formation) in the central region of the state of Rio Grande do Sul, Southern Brazil. In this area, dental fluorosis is an endemic disease. This paper presents the geochemical data and the combination of statistical analysis (Principal components and cluster analyses) and geochemical modeling to achieve the hydrogeochemistry of the groundwater and discusses the possible fluoride origin. The groundwater from the Santa Maria Formation is comprised of four different geochemical groups. The first group corresponds to a sodium chloride groundwater which evolves to sodium bicarbonate, the second one, both containing fluoride anomalies. The third group is represented by calcium bicarbonate groundwater, and in the fourth, magnesium is the distinctive parameter. The statistical and geochemical analyses supported by isotopic measurements indicated that groundwater may have originated from mixtures of deeper aquifers and the fluoride concentrations could be derived from rock/water interactions (e.g., desorption from clay minerals).

  5. Some aspects of the formulation of alginate dental impression materials--setting characteristics and mechanical properties.

    Science.gov (United States)

    Nallamuthu, Navina A; Braden, Michael; Patel, Mangala P

    2012-07-01

    To study the role of the various components of alginate dental impression materials. Experimental materials were formulated and their physical properties characterized and compared to commercially available counterparts (Neocolloid, Palgat Plus and Blueprint Cremix). Properties examined were: dimensional stability and weight change in water and artificial saliva; setting behavior; Shore A hardness and tear energy. The role of magnesium oxide was also investigated. Weight changes in water and artificial saliva can be attributed to an initial thermodynamic potential owing to the ionic content of the alginate, causing water to diffuse into the material. Water is then driven back out following a reversal of this potential. Hardness results for experimental materials were within the range obtained from the commercial materials. The hardness value for an experimental formulation that did not contain magnesium oxide was lower than values from the other experimental materials that did. Tear energies for all three experimental materials were greater than those of the commercial products. There were statistically significant differences between the two experimental materials that contained magnesium oxide and one that did not. With regard to setting time, statistically significant differences were seen between commercial materials and two of the experimental materials. The experimental material that did not contain magnesium oxide had a considerably longer setting time than all of the other materials tested. The key role of magnesium oxide in the setting reaction and the effect on hardness have been demonstrated and discussed. Copyright © 2012 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  6. Effect of fluoride in drinking water on children′s intelligence in high and low fluoride areas of Delhi

    Directory of Open Access Journals (Sweden)

    Hansa Kundu

    2015-01-01

    Full Text Available Introduction: Fluoride is one of the indispensable elements for the living being. However, the intake of F above the threshold level can affect the central nervous system even before causing dental or skeletal fluorosis. Aim: The aim was to assess the effect of fluoride in drinking water on the intelligence quotient (IQ of 8-12 years old school going children residing in high and low Fluoride (F areas of Delhi. Materials and Methods: A total of 200 school children were selected, 100 from low F area and 100 from high F area. The IQ of the children was assessed using Ravens Standardized Progressive Matrices Test. Information for each child′s sociodemographic data, mother′s diet during pregnancy, duration of residency in the village, source of drinking water, and duration of drinking water from the source was entered on a specially designed proforma from mothers of children. Height and weight were also recorded for each child to assess the nutritional status. Independent t-test and Chi-square test was used to compare mean IQ scores in high and low fluoridated areas. Pearson′s correlation and multivariate linear regression were used to appraise the issue of all the study variables on IQ. Results: Comparison of mean IQ of children in both high (76.20 ± 19.10 and low F (85.80 ± 18.85 areas showed a significant difference (P = 0.013. Multiple regression analysis between child IQ and all other independent variables revealed that mother′s diet during pregnancy (P = 0.001 along with F in drinking water (P = 0.017 were the independent variables with the greatest explanatory power for child IQ variance (r2 = 0.417 without interaction with other variables. Conclusion: Fluoride in the drinking water was significantly related with the IQ of children. Along with fluoride, mother′s diet during pregnancy was also found to be significantly related with IQ of children. Researches in the same field are further advocated with large sample size and over a

  7. Relationship between water, urine and serum fluoride and fluorosis in school children of Jhajjar District, Haryana, India

    Science.gov (United States)

    Kumar, Sunil; Lata, Suman; Yadav, Jyoti; Yadav, J. P.

    2017-10-01

    The present study was undertaken to determine the relationship between fluoride in water, urine and serum and dental fluorosis. The fluoride level in water and urine were measured spectrophotometrically by using acid zirconyl and SPADNS reagents, while the fluoride level in serum was determined by ion selective electrode meter. Dental fluorosis survey was conducted with the help of Performa prescribed by Rajiv Gandhi Drinking Water Mission and the use of Tooth Surface Index for Fluorosis. Mean fluoride values in water samples of Jhajjar City and Dadanpur and Dariyapur villages of Jhajjar District were measured to be 2.17 (range from 1.92 to 2.60 mg/L), 2.81 (range from 2.53 to 3.14 mg/L) and 2.22 mg/L (range from 1.63 to 3.33 mg/L), respectively. The mean fluoride values in the urine samples of children were found to be 1.51 (range from 0.05 to 2.64 mg/L), 1.71 (range from 0.69 to 2.80 mg/L) and 1.45 mg/L (range from 0.31 to 2.50 mg/L) at Jhajjar City and Dadanpur and Dariyapur sites, respectively. Serum fluoride was detected in the blood samples of children, who have high urinary fluoride at these three sites. The mean serum fluoride level was reported to be 0.15, 0.34 and 0.17 mg/L, respectively. A total of 842 children were also analyzed for dental fluorosis. The mean values of fluorosis-affected children in Jhajjar, Dadanpur and Dariyapur were 51.90, 94.63 and 36.84 %, respectively. A significantly positive correlation between water, urine, serum fluoride concentration and fluorosis was seen.

  8. Fluorides in groundwater and its impact on health.

    Science.gov (United States)

    Shailaja, K; Johnson, Mary Esther Cynthia

    2007-04-01

    Fluoride is a naturally occurring toxic mineral present in drinking water and causes yellowing of teeth, tooth problems etc. Fluorspar, Cryolite and Fluorapatite are the naturally occurring minerals, from which fluoride finds its path to groundwater through infiltration. In the present study two groundwater samples, Station I and Station II at Hyderabad megacity, the capital of Andhra Pradesh were investigated for one year from January 2001 to December 2001. The average fluoride values were 1.37 mg/l at Station I and 0.91 mg/l at Station II. The permissible limit given by BIS (1983) 0.6-1.2 mg/l and WHO (1984) 1.5 mg/l for fluoride in drinking water. The groundwaters at Station I exceeded the limit while at Station II it was within the limits. The study indicated that fluoride content of 0.5 mg/l is sufficient to cause yellowing of teeth and dental problems.

  9. Analysis of Phone Calls Regarding Fluoride Exposure made to New Jersey Poison Control Center from 2010 to 2012.

    Science.gov (United States)

    Shah, Sneha; Quek, Samuel; Ruck, Bruce

    2016-02-01

    ,671). Based on the data, there were no reports of lethality or toxicity due to acute fluoride exposure in New Jersey from 2010 through 2012. Symptomatic reports and informational inquiries were few. All adverse outcomes due to excessive fluoride intake were remedied with calcium as the antidote. Dental hygienists should educate patients on safety measures of fluoride-containing products and evaluate overall fluoride exposure prior to making recommendations. However, findings in this study suggest that levels of fluoride in available commercial products will not produce life-threatening events, even if taken in doses higher than recommended. Copyright © 2016 The American Dental Hygienists’ Association.

  10. Fluoridated elastomers: effect on the microbiology of plaque.

    Science.gov (United States)

    Benson, Philip E; Douglas, C W Ian; Martin, Michael V

    2004-09-01

    The objective of this study was to investigate the effect of fluoridated elastomeric ligatures on the microbiology of local dental plaque in vivo. This randomized, prospective, longitudinal, clinical trial had a split-mouth crossover design. The subjects were 30 patients at the beginning of their treatment with fixed orthodontic appliances in the orthodontic departments of the Liverpool and the Sheffield dental hospitals in the United Kingdom. The study consisted of 2 experimental periods of 6 weeks with a washout period between. Fluoridated elastomers were randomly allocated at the first visit to be placed around brackets on tooth numbers 12, 11, 33 or 22, 21, 43. Nonfluoridated elastomers were placed on the contralateral teeth. Standard nonantibacterial fluoridated toothpaste and mouthwash were supplied. After 6 weeks (visit 2), the elastomers were removed, placed in transport media, and plated on agar within 2 hours. Nonfluoridated elastomers were placed on all brackets for 1 visit to allow for a washout period. At visit 3, fluoridated elastomers were placed on the teeth contralateral to those that received them at visit 1. At visit 4, the procedures at visit 2 were repeated. Samples were collected on visits 2 and 4. A logistic regression was performed, with the presence or absence of streptococcal or anaerobic growth as the dependent variable. A mixed-effects analysis of variance was carried out with the percentage of streptococcal or anaerobic bacterial count as the dependent variable. The only significant independent variables were the subject variable (P =bacterial count and the visit variable for the percentage of streptococcal count (P =fluoridated or nonfluoridated elastomers was not significant for percentage of either streptococcal (P =.288) or anaerobic count (P =.230). Fluoridated elastomers are not effective at reducing local streptococcal or anaerobic bacterial growth after a clinically relevant time in the mouth.

  11. Adhesive dental materials

    International Nuclear Information System (INIS)

    Unlu, N.

    2005-01-01

    Two main classes of material are involved, the glass-ionomer cements and the composite resins. This investigation describes the way they are bonded to the tooth and highlights their differences. Glass ionomers develop a zone of interaction with the tooth as they age which ultimately gives an extremely strong bond, and results in excellent retention rates. By contrast, bonding of composite resins is more complicated and possibly less effective, though these materials have better wear resistance and better aesthetics than glass ionomers. Assessment of bond durability is difficult. This is because a dental restorative can fail by a number of mechanisms apart from de bonding: for example, through wear or fracture

  12. Dental caries in diabetes mellitus: role of salivary flow rate and minerals.

    Science.gov (United States)

    Jawed, Muhammad; Shahid, Syed M; Qader, Shah A; Azhar, Abid

    2011-01-01

    This study was designed to evaluate the possible protective role of salivary factors like salivary flow rate and adequate level of calcium, phosphate, and fluoride in diabetes mellitus type 2 patients with dental caries. A total of 398 diabetes mellitus type 2 patients with dental caries and 395 age- and sex-matched non-diabetic subjects with dental caries were included as controls, all of whom gave informed consent. All subjects were divided into four groups according to their age. Decayed, missed, and filled teeth (DMFT) were scored to indicate the severity of dental caries. Saliva was collected, flow rate was noted, and calcium, phosphate, and fluoride were analyzed. The blood glucose, HbA1c, and DMFT indices were found to be significantly high in diabetic patients as compared to controls. The salivary flow rate, calcium, phosphate, and fluoride were found to be significantly low whereas no significant difference was found in salivary magnesium in patients as compared to controls. Optimum salivary flow rate is responsible for establishing protective environment against dental caries. Adequate level of salivary calcium, phosphate, and fluoride is also involved in significant deposition of these minerals in plaque, which greatly reduces the development of caries in the adjacent enamel of teeth. Copyright © 2011 Elsevier Inc. All rights reserved.

  13. Controlling Magnetic and Ferroelectric Order Through Geometry: Synthesis, Ab Initio Theory, Characterization of New Multi-Ferric Fluoride Materials

    Energy Technology Data Exchange (ETDEWEB)

    Halasyamani, Shiv [Univ. of Houston, TX (United States); Fennie, Craig [Cornell Univ., Ithaca, NY (United States)

    2016-11-03

    We have focused on the synthesis, characterization, and ab initio theory on multi-functional mixed-metal fluorides. With funding from the DOE, we have successfully synthesized and characterized a variety of mixed metal fluoride materials.

  14. Use of Silver Diamine Fluoride for Dental Caries Management in Children and Adolescents, Including Those with Special Health Care Needs.

    Science.gov (United States)

    Crystal, Yasmi O; Marghalani, Abdullah A; Ureles, Steven D; Wright, John Timothy; Sulyanto, Rosalyn; Divaris, Kimon; Fontana, Margherita; Graham, Laurel

    2017-09-15

    This manuscript presents evidence-based guidance on the use of 38 percent silver diamine fluoride (SDF) for dental caries management in children and adolescents, including those with special health care needs. A guideline workgroup formed by the American Academy of Pediatric Dentistry developed guidance and an evidence-based recommendation regarding the application of 38 percent SDF to arrest cavitated caries lesions in primary teeth. The basis of the guideline's recommendation is evidence from an existing systematic review "Clinical trials of silver diamine fluoride in arresting caries among children: A systematic review." (JDR Clin Transl Res 2016;1[3]:201-10). A systematic search was conducted in PubMed®/MEDLINE, Embase®, Cochrane Central Register of Controlled Trials, and gray literature databases to identify randomized controlled trials and systematic reviews reporting on the effect of silver diamine fluoride and address peripheral issues such as adverse effects and cost. The Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach was used to assess the quality of the evidence and the evidence-to-decision framework was employed to formulate a recommendation. The panel made a conditional recommendation regarding the use of 38 percent SDF for the arrest of cavitated caries lesions in primary teeth as part of a comprehensive caries management program. After taking into consideration the low cost of the treatment and the disease burden of caries, panel members were confident that the benefits of SDF application in the target populations outweigh its possible undesirable effects. Per GRADE, this is a conditional recommendation based on low-quality evidence. Conclusions and practical implications: The guideline intends to inform the clinical practices involving the application of 38 percent SDF to enhance dental caries management outcomes in children and adolescents, including those with special health care needs. These recommended

  15. Dental hygiene work in a clinical trial.

    Science.gov (United States)

    Luís, H S; Morgado, I; Assunção, V; Bernardo, M F; Leroux, B; Martin, M D; DeRouen, T A; Leitão, J

    2008-08-01

    Dental hygiene activities were developed as part of a randomized clinical trial designed to assess the safety of low-level mercury exposure from dental amalgam restorations. Along with dental-hygiene clinical work, a community programme was implemented after investigators noticed the poor oral hygiene habits of participants, and the need for urgent action to minimize oral health problems in the study population. Clinical and community activity goal was to promote oral health and prevent new disease. Community activities involved participants and their fellow students and were aimed at providing education on oral health in a school environment. Dental hygienists developed clinical work with prophylaxis, sealants application and topical fluoride and implemented the community programme with in-class sessions on oral health themes. Twice a month fluoride mouthrinses and bi-annual tooth brushing instructional activity took place. Participation at dental-hygiene activities, sealed teeth with no need of restoration and dental-plaque-index were measures used to evaluate success of the programme for the participants. Improvement in dental hygiene is shown by the decrease in dental plaque index scores (P dental hygiene activities. Teachers became aware of the problem and included oral-health in school curricula. Dental hygiene activities have shown to be helpful to promote dental hygiene, promote oral health and to provide school-age children with education on habits that will be important for their future good health.

  16. Fuel salt and container material studies for MOSART transforming system

    Energy Technology Data Exchange (ETDEWEB)

    Ignatiev, V.; Feynberg, O.; Merzlyakov, A.; Surenkov, A.; Zagnitko, A. [National Research Center, Kurchatov Institute, Moscow (Russian Federation); Afonichkin, V.; Bovet, A.; Khokhlov, V. [Institute of High Temperature Electrochemisty, Ekaterinburg (Russian Federation); Subbotin, V.; Gordeev, M.; Panov, A.; Toropov, A. [Institute of Technical Physics, Snezhinsk (Russian Federation)

    2013-07-01

    A study is under progress to examine the feasibility of single stream Molten Salt Actinide Recycling and Transmuting system without and with Th support (MOSART) fuelled with different compositions of actinide tri-fluorides (AnF{sub 3}) from used LWR fuel. New fast-spectrum design options with homogeneous core and fuel salts with high enough solubility for AnF{sub 3} are being examined because of new goals. The flexibility of single fluid MOSART concept with Th support is underlined, particularly, possibility of its operation in self-sustainable mode (Conversion Ratio: CR=1) using different loadings and make up. The paper summarizes the most current status of fuel salt and container material data for the MOSART concept received within ISTC-3749 and ROSATOM-MARS projects. Key physical and chemical properties of various fluoride fuel salts are reported. The issues like salt purification, the electroreduction of U(IV) to U(III) in LiF-ThF{sub 4} and the electroreduction of Yb(III) to Yb(II) in LiF-NaF are detailed.

  17. Impact of Dental Fluorosis, Socioeconomic Status and Self-Perception in Adolescents Exposed to a High Level of Fluoride in Water

    Science.gov (United States)

    Molina-Frechero, Nelly; Nevarez-Rascón, Martina; Nevarez-Rascón, Alfredo; González-González, Rogelio; Irigoyen-Camacho, María Esther; Sánchez-Pérez, Leonor; López-Verdin, Sandra; Bologna-Molina, Ronell

    2017-01-01

    Objective: To identify adolescents’ self-perception of dental fluorosis from two areas with different socioeconomic levels. Methods: A cross-sectional, descriptive study was conducted with 15-year-old youths by applying a questionnaire designed and validated to assess self-perceptions of dental fluorosis in two areas with different socioeconomic statuses (SESs). Fluorosis was clinically evaluated by applying the Thylstrup and Fejerkov (TF) index on the upper front teeth. Results: A total of 308 adolescents were included in the study. The medium-SES population, which was exposed to 2.5 ppm of fluoride in water, and the low-SES population, which was exposed to 5.1 ppm, presented the following levels of dental fluorosis: TF 2–3 (50%), TF 4–5 (45.6%) and TF 6–7 (4.4%) for medium SES and TF 2–3 (12.3%), TF 4–5 (67.1%) and TF 67 (20.6%) for low SES. A significant association was found between self-perception and dental fluorosis in those with medium and low SESs (p < 0.05). The multiple regression model found differences between TF levels and self-perception, with a 6–7 TF level for concerns about color (OR = 1.6), smile (OR = 1.2) and appearance (OR = 3.36). Conclusions: Self-perceptions of dental fluorosis affect adolescents such that adolescents with a medium SES have more negative perceptions than those with a low SES. Such perceptions increase as the TF index increases. PMID:28085102

  18. Impact of Dental Fluorosis, Socioeconomic Status and Self-Perception in Adolescents Exposed to a High Level of Fluoride in Water

    Directory of Open Access Journals (Sweden)

    Nelly Molina-Frechero

    2017-01-01

    Full Text Available Objective: To identify adolescents’ self-perception of dental fluorosis from two areas with different socioeconomic levels. Methods: A cross-sectional, descriptive study was conducted with 15-year-old youths by applying a questionnaire designed and validated to assess self-perceptions of dental fluorosis in two areas with different socioeconomic statuses (SESs. Fluorosis was clinically evaluated by applying the Thylstrup and Fejerkov (TF index on the upper front teeth. Results: A total of 308 adolescents were included in the study. The medium-SES population, which was exposed to 2.5 ppm of fluoride in water, and the low-SES population, which was exposed to 5.1 ppm, presented the following levels of dental fluorosis: TF 2–3 (50%, TF 4–5 (45.6% and TF 6–7 (4.4% for medium SES and TF 2–3 (12.3%, TF 4–5 (67.1% and TF 67 (20.6% for low SES. A significant association was found between self-perception and dental fluorosis in those with medium and low SESs (p < 0.05. The multiple regression model found differences between TF levels and self-perception, with a 6–7 TF level for concerns about color (OR = 1.6, smile (OR = 1.2 and appearance (OR = 3.36. Conclusions: Self-perceptions of dental fluorosis affect adolescents such that adolescents with a medium SES have more negative perceptions than those with a low SES. Such perceptions increase as the TF index increases.

  19. An evaluation of dental operative simulation materials.

    Science.gov (United States)

    He, Li-Hong; Foster Page, Lyndie; Purton, David

    2012-01-01

    The study was to evaluate the performance of different materials used in dental operative simulation and compare them with those of natural teeth. Three typical phantom teeth materials were compared with extracted permanent teeth by a nanoindentation system and evaluated by students and registered dentists on the drilling sensation of the materials. Moreover, the tool life (machinability) of new cylindrical diamond burs on cutting the sample materials was tested and the burs were observed. Although student and dentist evaluations were scattered and inconclusive, it was found that elastic modulus (E) and hardness (H) were not the main factors in determining the drilling sensation of the materials. The sensation of drilling is a reflection of cutting force and power consumption.An ideal material for dental simulation should be able to generate similar drilling resistance to that of natural tooth, which is the machinability of the material.

  20. Urinary fluoride excretion by children 4-6 years old in a south Texas community

    Directory of Open Access Journals (Sweden)

    Ramon J. Baez

    2000-04-01

    Full Text Available This study evaluated urinary fluoride excretion by school children 4-6 years old who were living in a south Texas rural community that had concentrations of fluoride in drinking water supplies generally around the optimal level. We took supervised collections of urine samples in the morning and afternoon at school, and parents of the participating students collected nocturnal samples. We recorded the beginning and end times of the three collection periods and then determined the urinary volume and urinary flow for each of the periods. We measured urinary fluoride concentrations and calculated the urinary excretion rate per hour. The children had breakfast and lunch provided at the school, where the drinking water contained 1.0-1.3 milligrams/liter (mg/L fluoride. Fluoride concentrations in the tested household water supplies, from wells, ranged from 0.1 to 3.2 mg/L fluoride. The children's average urinary fluoride concentrations found for the day were similar to those for the night, with means ranging from 1.26 mg/L to 1.42 mg/L. Average excretion was 36.4 µg/h in the morning, 45.6 µg/h in the afternoon, and 17.5 µg/h at night. The lower nocturnal excretion rates are easily explained by low urinary flow at night. Based on the 15 hours of urine collected, the extrapolated 24-hour fluoride excretion was 749 µg. In conjunction with similar studies, the data from this study will help in developing upper limits for urinary fluoride excretion that are appropriate for avoiding unsightly fluorosis while providing optimal protection against dental decay.

  1. Antifungal Effect of a Dental Tissue Conditioner Containing Nystatin-Loaded Alginate Microparticles.

    Science.gov (United States)

    Kim, Hyun-Jin; Son, Jun Sik; Kwon, Tae-Yub

    2018-02-01

    In this in vitro study, nystatin-alginate microparticles were successfully fabricated to control the release of nystatin from a commercial dental tissue conditioner. These nystatin-alginate microparticles were spherical and had a slightly rough surface. The microparticles incorporated into the tissue conditioner were distributed homogeneously throughout the tissue conditioner matrix. The incorporation of the microparticles did not deteriorate the mechanical properties of the original material. The agar diffusion test results showed that the tissue conditioner containing the microparticles had a good antifungal effect against Candida albicans. The nystatin-alginate microparticles efficiently controlled the release of nystatin from the tissue conditioner matrix over the experimental period of 14 days. Moreover, the nystatin-alginate microparticles incorporated in the tissue conditioner showed effective antifungal function even at lower concentrations of nystatin. The current study suggests that the tissue conditioner containing the nystatin-alginate microparticle carrier system has potential as an effective antifungal material.

  2. Perspectives in the effective use of fluoride in Asia

    DEFF Research Database (Denmark)

    Petersen, P E; Phantumvanit, P

    2012-01-01

    Dental caries is the most prevalent chronic disease affecting human populations worldwide. The diverse disease patterns across and within countries are related to socio-behavioral determinants, demographic factors, environmental conditions, and the availability and accessibility of oral health...... services, in particular, exposure to disease prevention programs (Petersen, 2003, 2008a). Benefits of fluoride for caries prevention have been substantiated in many countries (Petersen and Lennon, 2004; Jones et al., 2005). In the second half of the 20th century, this focus shifted to the development...... al., 2003; Australian Government, 2007). The Asian workshop held in Phan-Nga, Thailand, during March 22-24, 2011, aimed to discuss current information on fluoride and dental caries, as well as to try identifying barriers and opportunities that countries of Asia may have for implementing such programs...

  3. Recovery of uranium and lining material from magnesium fluoride slag at UMP

    International Nuclear Information System (INIS)

    Bandyopadhyay, P.K.; Singh, H.; Shadakshari, B.M.; Meghal, A.M.

    1991-01-01

    At Uranium Metal Plant, uranium metal is produced by reduction of UF 4 with magnesium metal, in a closed reactor lined with refractory MgF 2 lining material. During this reduction, more MgF 2 is produced as the slag. This slag generally contains 2-4% uranium and hence is processed to recover these values and part of the slag, free from uranium is reused for lining the reactor. This paper describes the process parameters finalised for crushing and grinding of the slag and for leaching uranium with nitric acid. The leach liquor contains appreciable amount of fluoride and hence is processed through a separate solvent extraction cycle with tributyl phosphate. The resultant purified uranyl nitrate solution is mixed with the main stream crude solution for final purification. The conditions optimised for the solvent extraction step, the problems faced during the regular operation over the last few years and the experience gained are described. An outline of the scheme to treat larger quantities of the slag on a regular basis is presented. (author). 6 refs., 1 fig., 1 tab

  4. Statistical analysis of fluoride levels in human urine and drinking water samples of fluorinated area of punjab (pakistan)

    International Nuclear Information System (INIS)

    Qayyum, M.; Zaman, W.U.; Rehman, R.; Ahmad, B.; Ahmad, M.; Ali, S.; Murtaza, S

    2013-01-01

    Increasing fluoride levels in drinking water of fluorinated areas of world leading to fluorosis. For bio-monitoring of fluorosis patients, fluoride levels were determined in drinking water and human urine samples of different individuals having dental fluorosis and bony deformities from fluorotic area of Punjab (Sham Ki Bhatiyan, Pakistan) and then compared with reference samples of non fluorotic area (Queens Road, Lahore, Pakistan) using ion selective electrode methodology. Fluoride levels in fluorinated area differ significantly from control group (p < 0.05). In drinking water and human urine samples, fluoride levels in fluorinated areas were: 136.192 +- 67.836 and 94.484 +- 36.572 micro molL/sup -1/ respectively, whereas in control samples, fluoride concentrations were: 19.306 +- 2.109 and 47.154 +- 22.685 micro molL/sup -1/ in water and urine samples correspondingly. Pearson's correlation data pointed out the fact that that human urine and water fluoride concentrations have a significant positive dose response relationship with the prevalence of dental and skeletal fluorosis in fluorotic areas having higher fluoride levels in drinking water. (author)

  5. Influence of metal dental materials on MR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Tsuchihashi, Toshio; Chiba, Michiko; Yoshizawa, Satoshi; Sasaki, Sadayuki; Maki, Toshio; Kitagawa, Matsuo; Suzuki, Takeshi [Nippon Medical School, Tokyo (Japan). Main Hospital; Nakata, Minoru; Fujita, Isao

    1998-11-01

    Differences in magnetic susceptibility produce artifacts and signal loss in magnetic resonance imaging (MRI). This study was undertaken to compare the degree of artifacts on MRI caused by metallic dental materials. The influence on MRI of six types of dental alloys, a dental implant, orthodontic appliance, and magnetic attachment was investigated. Among the dental metals, nickel-chromium alloy and cobalt-chromium alloy, which have ferromagnetism, caused significant metal artifacts. Gold-platinum alloy, gold-silver-palladium alloy, silver alloy, and amalgam alloy produced slight metal artifacts. The orthodontic appliance mainly consisted of iron, and the keeper for its magnetic attachment was made of stainless steel. For these reasons, marked metal artifacts and signal loss could be seen in both of them owing to their ferromagnetism. These results suggest that orthodontic appliances and magnetic attachments impair evaluation of the GRE and EPI techniques. It is therefore preferable to use predominantly diamagnetic or paramagnetic dental materials for MRI of the head and neck. Removable keepers should be used more widely to prevent metal artifacts and enhance safety on MRI. (author)

  6. Influence of metal dental materials on MR imaging

    International Nuclear Information System (INIS)

    Tsuchihashi, Toshio; Chiba, Michiko; Yoshizawa, Satoshi; Sasaki, Sadayuki; Maki, Toshio; Kitagawa, Matsuo; Suzuki, Takeshi; Nakata, Minoru; Fujita, Isao

    1998-01-01

    Differences in magnetic susceptibility produce artifacts and signal loss in magnetic resonance imaging (MRI). This study was undertaken to compare the degree of artifacts on MRI caused by metallic dental materials. The influence on MRI of six types of dental alloys, a dental implant, orthodontic appliance, and magnetic attachment was investigated. Among the dental metals, nickel-chromium alloy and cobalt-chromium alloy, which have ferromagnetism, caused significant metal artifacts. Gold-platinum alloy, gold-silver-palladium alloy, silver alloy, and amalgam alloy produced slight metal artifacts. The orthodontic appliance mainly consisted of iron, and the keeper for its magnetic attachment was made of stainless steel. For these reasons, marked metal artifacts and signal loss could be seen in both of them owing to their ferromagnetism. These results suggest that orthodontic appliances and magnetic attachments impair evaluation of the GRE and EPI techniques. It is therefore preferable to use predominantly diamagnetic or paramagnetic dental materials for MRI of the head and neck. Removable keepers should be used more widely to prevent metal artifacts and enhance safety on MRI. (author)

  7. High Fluoride Dentifrices for Elderly and Vulnerable Adults

    DEFF Research Database (Denmark)

    Ekstrand, Kim Rud

    2016-01-01

    The primary aim of this work is to present the available evidence that toothpastes containing >1,500 ppm fluoride (2,500-2,800 and 5,000 ppm F) provide an additional caries preventive effect on root caries lesions in elderly patients compared to traditional dentifrices (1,000-1,450 ppm F......). The secondary aim of this paper is to discuss why high fluoride dentifrices in general should perform better than traditional F-containing toothpaste. When examining the few studies that have considered the preventive benefits of high fluoride products on root caries the relative risk appears to be around 0.......5, and the risk can thus be halved by exchanging traditional F-containing toothpaste for toothpaste containing 5,000 ppm F. There is reasonable evidence that high fluoride dentifrices significantly increase the fluoride concentration in saliva during the day and the fluoride concentration in plaque compared...

  8. Optical investigations of various polymeric materials used in dental technology

    Science.gov (United States)

    Negrutiu, Meda Lavinia; Sinescu, Cosmin; Topala, Florin Ionel; Ionita, Ciprian; Goguta, Luciana; Marcauteanu, Corina; Rominu, Mihai; Podoleanu, Adrian Gh.

    2011-10-01

    Dental prosthetic restorations have to satisfy high stress as well as aesthetic requirements. In order to avoid deficiencies of dental prostheses, several alternative systems and procedures were imagined, directly related to the material used and also to the manufacturing technology. Increasing the biomechanical comportment of polymeric materials implies fiber reinforcing. The different fibers reinforcing products made very difficult the evaluation of their performances and biomechanical properties analysis. There are several known methods which are used to assess the quality of dental prostheses, but most are invasive. These lead to the destruction of the samples and often no conclusion could be drawn in the investigated areas of interest. Using a time domain en-face OCT system, we have recently demonstrated real time thorough evaluation of quality of various dental treatments. The aim of this study was to assess the quality of various polymeric materials used in dental technology and to validate the en face OCT imagistic evaluation of polymeric dental prostheses by using scanning electron microscopy (SEM) and microcomputer tomography (μCT). SEM investigations evidenced the nonlinear aspect of the interface between the polymeric material and the fiber reinforcement and materials defects in some samples. The results obtained by microCT revealed also some defects inside the polymeric materials and at the interfaces with the fiber reinforcement. The advantages of the OCT method consist in non-invasiveness and high resolution. In addition, en face OCT investigations permit visualization of the more complex stratified structure at the interface between the polymeric material and the fiber reinforcement.

  9. Recent Advances in Material and Geometrical Modelling in Dental Applications

    Directory of Open Access Journals (Sweden)

    Waleed M. S. Al Qahtani

    2018-06-01

    Full Text Available This article touched, in brief, the recent advances in dental materials and geometric modelling in dental applications. Most common categories of dental materials as metallic alloys, composites, ceramics and nanomaterials were briefly demonstrated. Nanotechnology improved the quality of dental biomaterials. This new technology improves many existing materials properties, also, to introduce new materials with superior properties that covered a wide range of applications in dentistry. Geometric modelling was discussed as a concept and examples within this article. The geometric modelling with engineering Computer-Aided-Design (CAD system(s is highly satisfactory for further analysis or Computer-Aided-Manufacturing (CAM processes. The geometric modelling extracted from Computed-Tomography (CT images (or its similar techniques for the sake of CAM also reached a sufficient level of accuracy, while, obtaining efficient solid modelling without huge efforts on body surfaces, faces, and gaps healing is still doubtable. This article is merely a compilation of knowledge learned from lectures, workshops, books, and journal articles, articles from the internet, dental forum, and scientific groups' discussions.

  10. Energy dispersive X-ray spectrometry study of the protective effects of fluoride varnish and gel on enamel erosion.

    Science.gov (United States)

    De Carvalho Filho, Antonio Carlos Belfort; Sanches, Roberto Pizarro; Martin, Airton Abrahão; Do Espírito Santo, Ana Maria; Soares, Luís Eduardo Silva

    2011-09-01

    Dental erosion is a risk factor for dental health, introduced by today's lifestyle. Topical fluoride applications in the form of varnishes and gel may lead to deposition of fluoride on enamel. This in vitro study aimed to evaluate the effect of two fluoride varnishes and one fluoride gel on the dissolution of bovine enamel by acids. Enamel samples (72) were divided (n = 8): artificial saliva (control-G1), Pepsi Twist® (G2), orange juice (G3), Duraphat® + Pepsi Twist® (G4), Duraphat® + orange juice (G5), Duofluorid® + Pepsi Twist® (G6), Duofluorid® + orange juice (G7), fluoride gel + Pepsi Twist® (G8), and fluoride gel + orange juice (G9). Fluoride gel was applied for 4 min and the varnishes were applied and removed after 6 h. The samples were submitted to six cycles (demineralization: Pepsi Twist® or orange juice, 10 min; remineralization: saliva, 1 h). Samples were analyzed by energy-dispersive X-ray fluorescence (144 line-scanning). The amount of Ca and P decreased significantly in the samples of G2 and G3, and the Ca/P ratio decreased in G3. Mineral gain (Ca) was greater in G9 samples than in G4 > G3 > G5 > G1, and (P) greater in G7 samples than in G9 > G4-6 > G2-3. The protective effect of Duofluorid® was significantly lower than fluoride gel against orange juice. The fluoride varnishes can interfere positively with the dissolution of dental enamel in the presence of acidic beverages. Fluoride gel showed the best protection level to extrinsic erosion with low costs. Copyright © 2010 Wiley-Liss, Inc.

  11. Radiation-induced dental caries, prevention and treatment - A systematic review.

    Science.gov (United States)

    Gupta, Nishtha; Pal, Manoj; Rawat, Sheh; Grewal, Mandeep S; Garg, Himani; Chauhan, Deepika; Ahlawat, Parveen; Tandon, Sarthak; Khurana, Ruparna; Pahuja, Anjali K; Mayank, Mayur; Devnani, Bharti

    2015-01-01

    Treatment of head and neck cancers (HNCs) involves radiotherapy. Patients undergoing radiotherapy for HNCs are prone to dental complications. Radiotherapy to the head and neck region causes xerostomia and salivary gland dysfunction which dramatically increases the risk of dental caries and its sequelae. Radiation therapy (RT) also affects the dental hard tissues increasing their susceptibility to demineralization following RT. Postradiation caries is a rapidly progressing and highly destructive type of dental caries. Radiation-related caries and other dental hard tissue changes can appear within the first 3 months following RT. Hence, every effort should be focused on prevention to manage patients with severe caries. This can be accomplished through good preoperative dental treatment, frequent dental evaluation and treatment after RT (with the exception of extractions), and consistent home care that includes self-applied fluoride. Restorative management of radiation caries can be challenging. The restorative dentist must consider the altered dental substrate and a hostile oral environment when selecting restorative materials. Radiation-induced changes in enamel and dentine may compromise bonding of adhesive materials. Consequently, glass ionomer cements have proved to be a better alternative to composite resins in irradiated patients. Counseling of patients before and after radiotherapy can be done to make them aware of the complications of radiotherapy and thus can help in preventing them.

  12. Evaluation of radiation effects on dental enamel hardness and dental restorative materials; Avaliacao do efeito da irradiacao na dureza do esmalte dental e de materiais odontologicos

    Energy Technology Data Exchange (ETDEWEB)

    Adachi, Lena Katekawa; Saiki, Mitiko [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo, SP (Brazil). Supervisao de Radioquimica; Campos, Tomie Nakakuki [Sao Paulo Univ., SP (Brazil). Faculdade de Odontologia. Dept. de Protese

    2000-07-01

    This research presents the results of the microhardness of human dental enamel and of the following dental restorative materials: three dental porcelains - Ceramco II, Finesse and Noritake, and two resin restorative materials - Artglass and Targis, for materials submitted to different times of irradiation at the IEA-R1m nuclear reactor under a thermal neutron flux of 10{sup 12}n cm{sup -2}.s{sup -1} . The results obtained indicated that there is a decrease of the surface microhardness when the enamel is irradiated for 1 h and when dental materials are irradiated for 3 h. However, enamels irradiated for 30 min. did not show significant change of their surface hardness. Therefore, the selection of irradiation time is an important factor to be considered when irradiated teeth or dental materials are used in the investigations of their properties. (author)

  13. [In vivo retention of KOH soluble and firmly bound fluoride in demineralized dental enamel].

    Science.gov (United States)

    Hellwig, E; Klimek, J; Albert, G

    1989-03-01

    Cylindrical enamel blocks with initial carious lesions were treated for one hour with Duraphat or Fluor-Protector. After removal of the fluoride varnishes the enamel blocks were kept in the mouths of 3 probands for 5 days. Plaque was allowed to accumulate on half of the enamel cylinders, while the other half was kept clean. Part of the enamel cylinders were retained as fluoridated controls. Compared with Duraphat the application of Fluor-Protector resulted in a significantly higher uptake of KOH soluble and firmly bound fluoride. During the 5 days of the experiment the amount of KOH soluble fluorides decreased in both groups. In the presence of plaque the fluoride loss was higher. The amount of firmly bound fluoride increased both in the plaque covered and in the clean enamel. The durable cariostatic effect of fluoridated varnishes seems to be due to the slow dissolution of Ca F2-like precipitates on the enamel surface and the concomitant fluoride uptake in the underlying demineralized enamel.

  14. Structure–property relationships in hybrid dental nanocomposite resins containing monofunctional and multifunctional polyhedral oligomeric silsesquioxanes

    Directory of Open Access Journals (Sweden)

    Wang WG

    2014-02-01

    Full Text Available Weiguo Wang,1,* Xiang Sun,1,* Li Huang,2,* Yu Gao,1 Jinghao Ban,1 Lijuan Shen,1 Jihua Chen1 1Department of Prosthodontics, 2Department of General Dentistry and Emergency, School of Stomatology, Fourth Military Medical University, Xi'an, People's Republic of China*These authors contributed equally to this workAbstract: Organic-inorganic hybrid materials, such as polyhedral oligomeric silsesquioxanes (POSS, have the potential to improve the mechanical properties of the methacrylate-based composites and resins used in dentistry. In this article, nanocomposites of methacryl isobutyl POSS (MI-POSS [bears only one methacrylate functional group] and methacryl POSS (MA-POSS [bears eight methacrylate functional groups] were investigated to determine the effect of structures on the properties of dental resin. The structures of the POSS-containing networks were determined by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, and Fourier transform infrared spectroscopy. Monofunctional POSS showed a strong tendency toward aggregation and crystallization, while multifunctional POSS showed higher miscibility with the dimethacrylate monomer. The mechanical properties and wear resistance decreased with increasing amounts of MI-POSS, indicating that the MI-POSS agglomerates act as the mechanical weak point in the dental resins. The addition of small amounts of MA-POSS improved the mechanical and shrinkage properties. However, samples with a higher MA-POSS concentration showed lower flexural strength and flexural modulus, indicating that there is a limited range in which the reinforcement properties of MA-POSS can operate. This concentration dependence is attributed to phase separation at higher concentrations of POSS, which affects the structural integrity, and thus, the mechanical and shrinkage properties of the dental resin. Our results show that resin with 3% MA-POSS is a potential candidate for resin-based dental materials

  15. ATR technique, an appropriate method for determining the degree of conversion in dental giomers

    International Nuclear Information System (INIS)

    Prejmerean, Cristina; Prodan, Doina; Vlassa, Mihaela; Prejmerean, Vasile; Cuc, Stanca; Moldovan, Marioara; Streza, Mihaela; Buruiana, Tinca; Colceriu, Loredana

    2016-01-01

    Dental light-curing giomers were developed to combine the favourable properties of diacrylic resin composites (DRCs) and glass-ionomer cements (GICs) in a single material and to eliminate their inherent drawbacks. Giomers are characterized by their aesthetic appearance, high mechanical properties, adhesion to dental tissues as well as fluoride release and recharge abilities. The qualities of the giomers are greatly influenced by the level of conversion of the component resins. Infrared spectroscopy is one of the most largely used techniques for the determination of the degree of conversion in resin-based dental materials. However different results were obtained due to the performances of the used methods. The present work presents the determination of conversion degree in a series of dental copolymers and their corresponding giomers using transmission Fourier transform infrared spectroscopy (FTIR) and an attenuated total reflection technique (ATR) technique, respectively, the main aim being the study of the influence of the materials composition and of the light curing modes upon the achieved conversion in the cured giomers. Beautifil II commercial giomer was used as a control. A halogen lamp and a diode-blue LED lamp were used for the curing of the materials. The results showed that the composition of the resins greatly influenced the conversion. The highest conversions (up to 79%) were obtained in the case of the experimental giomers which contained the experimental Bis-GMA urethane analogue, followed by the Beautifil II giomer (61%) and experimental giomers based on commercial Bis-GMA (up to 50%), respectively. The resins light-cured by using the diode-blue LED lamp presented slightly higher conversions than the resins cured by halogen lamp. The study demonstrates the possibility to evaluate easily and reproducibly the conversion in light-curing composite materials with complex chemical composition and structure, particularly in the case of giomers by using the

  16. A cross-sectional study to assess the intelligence quotient (IQ of school going children aged 10-12 years in villages of Mysore district, India with different fluoride levels

    Directory of Open Access Journals (Sweden)

    Shibu Thomas Sebastian

    2015-01-01

    Full Text Available Introduction: Besides dental and skeletal fluorosis, excessive fluoride intake can also affect the central nervous system without first causing the physical deformities associated with skeletal fluorosis. With the existence of widespread endemic fluorosis in India, the possible adverse effect of elevated fluoride in drinking water on the Intelligence Quotient (IQ level of children is a potentially serious public health problem. Aims and Objectives: This study assessed the Intelligence Quotient (IQ of school going children aged 10-12 years in villages of Mysore district with different fluoride levels. Materials and Methods: In this cross-sectional study, 405 school children aged 10-12 years were selected from three villages in Mysore district with normal fluoride (1.20 mg F/l, low fluoride (0.40 mg F/l and high fluoride (2.20 mg F/l in their water supplies. A pre designed questionnaire was used to collect the required data for the survey which included socio demographic details, oral hygiene practices, diet history, body mass index and dental fluorosis. Intelligence Quotient was assessed using Raven′s colored Progressive Matrices Test. Results: In bivariate analysis, significant relationships were found between water fluoride levels and Intelligence Quotient of school children (P < 0.05. In the high fluoride village, the proportion of children with IQ below 90, i.e. below average IQ was larger compared to normal and low fluoride village. Age, gender, parent education level and family income had no significant association with IQ. Conclusion: School children residing in area with higher than normal water fluoride level demonstrated more impaired development of intelligence when compared to school children residing in areas with normal and low water fluoride levels. Thus, children′s intelligence can be affected by high water fluoride levels.

  17. A useful and non-invasive microanalysis method for dental restoration materials

    International Nuclear Information System (INIS)

    Hosoki, M.; Satsuma, T.; Nishigawa, K.; Takeuchi, H.; Asaoka, K.

    2012-01-01

    Highlights: ► This method for the microanalysis of dental alloys is beneficial for patients with allergies to dental materials. ► This metal sample is easy to mail it for inspection at specialist institutes. ► This method can be also be used in general dental clinics. - Abstract: The elemental analysis of intraoral dental restorations provides considerable information for the treatment of dental metal allergy. Elemental analyses require specific instruments and complicated procedures, so this examination is not commonly carried out in private dental clinics. We describe a novel, simple and useful micro-analytical method for dental metal restorations. Micro metal dust was obtained by polishing the surface of restorative metal material with an unused silicone point (SUPER-SNAP). The metal dust on the silicone point was then rubbed onto adhesive tape, and this tape was covered with polyethylene film. The amount of metal dust material was <20 μg. An energy dispersive X-ray fluorescence spectrometer was used to carry out the elementary analysis of the metal dust on the polyethylene film. Three types of dental metal alloy materials of known components were examined. The results of elementary analyses were compared with the specifications provided by the manufacturer. The same procedure was carried out for three dental metal restorations of an adult female volunteer in vivo. The results of elemental analyses for five alloy materials exactly matched the product specification. Three metal samples obtained from intraoral restoration were also available for elemental analyses. The distinct advantage of this method is that it enables sample extraction without an invasive effect for the restoration. The metal sample is in a polyethylene film, so it is easy to mail it for inspection at specialist institutes yet it can be also be used in general dental clinics.

  18. A useful and non-invasive microanalysis method for dental restoration materials

    Energy Technology Data Exchange (ETDEWEB)

    Hosoki, M., E-mail: hosoki@tokushima-u.ac.jp [Department of Fixed Prosthodontics, Institute of Health Biosciences, University of Tokushima Graduate School, 3-18-15 Kuramoto-cho, Tokushima 770-8504 (Japan); Satsuma, T.; Nishigawa, K.; Takeuchi, H. [General Dentistry, Tokushima University Hospital, 3-18-15 Kuramoto-cho, Tokushima 770-8504 (Japan); Asaoka, K. [Department of Biomaterials and Bioengineering, Institute of Health Biosciences, University of Tokushima Graduate School, 3-18-15 Kuramoto-cho, Tokushima 770-8504 (Japan)

    2012-12-01

    Highlights: Black-Right-Pointing-Pointer This method for the microanalysis of dental alloys is beneficial for patients with allergies to dental materials. Black-Right-Pointing-Pointer This metal sample is easy to mail it for inspection at specialist institutes. Black-Right-Pointing-Pointer This method can be also be used in general dental clinics. - Abstract: The elemental analysis of intraoral dental restorations provides considerable information for the treatment of dental metal allergy. Elemental analyses require specific instruments and complicated procedures, so this examination is not commonly carried out in private dental clinics. We describe a novel, simple and useful micro-analytical method for dental metal restorations. Micro metal dust was obtained by polishing the surface of restorative metal material with an unused silicone point (SUPER-SNAP). The metal dust on the silicone point was then rubbed onto adhesive tape, and this tape was covered with polyethylene film. The amount of metal dust material was <20 {mu}g. An energy dispersive X-ray fluorescence spectrometer was used to carry out the elementary analysis of the metal dust on the polyethylene film. Three types of dental metal alloy materials of known components were examined. The results of elementary analyses were compared with the specifications provided by the manufacturer. The same procedure was carried out for three dental metal restorations of an adult female volunteer in vivo. The results of elemental analyses for five alloy materials exactly matched the product specification. Three metal samples obtained from intraoral restoration were also available for elemental analyses. The distinct advantage of this method is that it enables sample extraction without an invasive effect for the restoration. The metal sample is in a polyethylene film, so it is easy to mail it for inspection at specialist institutes yet it can be also be used in general dental clinics.

  19. Effect of fluoride mouthwash on tensile strength of stainless steel orthodontic archwires

    Science.gov (United States)

    Fatimah, D. I.; Anggani, H. S.; Ismah, N.

    2017-08-01

    Patients with orthodontic treatment are commonly recommended to use a fluoride mouthwash for maintaining their oral hygiene and preventing dental caries. However, fluoride may affect the characteristics of stainless steel orthodontic archwires used during treatment. The effect of fluoride mouthwash on the tensile strength of stainless steel orthodontic archwires is still unknown. The purpose of this study is to know the effect of fluoride mouthwash on the tensile strength of stainless steel orthodontic archwires. Examine the tensile strength of 0.016 inch stainless steel orthodontic archwires after immersion in 0.05%, 100 ml fluoride mouthwash for 30, 60, and 90 min. There is no statistically significant difference in the tensile strength of stainless steel orthodontic archwires after immersed in fluoride mouthwash. The p-values on immersion fluoride mouthwash for 30, 60, and 90 min consecutively are 0.790; 0.742; and 0.085 (p > 0.05). The use of fluoride mouthwash did not have an effect on the tensile strength of stainless Steel orthodontic archwires.

  20. Various Effects of Sandblasting of Dental Restorative Materials.

    Directory of Open Access Journals (Sweden)

    Goro Nishigawa

    Full Text Available Sandblasting particles which remain on the surfaces of dental restorations are removed prior to cementation. It is probable that adhesive strength between luting material and sandblasting particle remnants might exceed that with restorative material. If that being the case, blasting particles adhere to sandblasted material surface could be instrumental to increasing adhesive strength like underlying bonding mechanism between luting material and silanized particles of tribochemical silica coating-treated surface. We hypothesize that ultrasonic cleaning of bonding surfaces, which were pretreated with sandblasting, may affect adhesive strength of a resin luting material to dental restorative materials.We therefore observed adhesive strength of resin luting material to aluminum oxide was greater than those to zirconia ceramic and cobalt-chromium alloy beforehand. To measure the shear bond strengths of resin luting material to zirconia ceramic and cobalt-chromium alloy, forty specimens of each restorative material were prepared. Bonding surfaces were polished with silicon abrasive paper and then treated with sandblasting. For each restorative material, 40 sandblasted specimens were equally divided into two groups: ultrasonic cleaning (USC group and non-ultrasonic cleaning (NUSC group. After resin luting material was polymerized on bonding surface, shear test was performed to evaluate effect of ultrasonic cleaning of bonding surfaces pretreated with sandblasting on bond strength.For both zirconia ceramic and cobalt-chromium alloy, NUSC group showed significantly higher shear bond strength than USC group.Ultrasonic cleaning of dental restorations after sandblasting should be avoided to retain improved bonding between these materials.

  1. The effect of propolis fluoride on caries dentine activity

    Science.gov (United States)

    Darwita, Risqa Rina; Soekanto, Sri Angky; Finisha, Andanali Rhukul; Wahyuni, Hardiati Nur; Andiani, Salsabila Ghina

    2018-02-01

    This research was conducted to analyze the effect of propolis fluoride on the occurrence of arrested caries dentine surface. The design of the study was a clinical trial experimental. The respondent were primary school students aged 6-8 years, from primary school in Kukusan, Depok, West Java, Indonesia. They were screened of dental examination and the total number of 296 children with an age range of 6-8 year old were included in the study. All students who had dentin caries were get dental treatment with propolis fluoride topical application in dentin caries surface. After one month, two months and four months all students who were got propolis fluoride topical application in dentin caries surface were controlled. All data were analyzed by Wilcoxon test. The total number of dentinal decay of 296 student was 1740 surfaces indicated to Flolis topical application. After one, two and three months of Flolis application, all arrested of dentinal decay was evaluated, the result of evaluation from the second month to the third month evaluation was found that the arrested dentinal caries surfaces were decreased significantly at 29.36% (pcaries surface from the first month to the third month was decreased significantly at 38.62% (pcaries, and their ability to arrest dental caries was significantly different. Flolis was found to be effective in arresting dentinal caries surface until three months application, and should be repeated after 3 months of Flolis application.

  2. Data on fluoride concentration levels in semi-arid region of Medak, Telangana, South India

    Directory of Open Access Journals (Sweden)

    Adimalla Narsimha

    2018-02-01

    Full Text Available According to the World Health Organization recommendation, the optimal fluoride concentration levels in drinking water have to be in the range of 0.5 and 1.5 mg/L since this permissible range is essential for normal mineralization of bones and teeth as well as for dental enamel formation in human's body Bell and budwig, 1970; Adimalla and Venkatayogi, 2017; Narsimha and Sudarshan, 2013, 2016; 2017 [1,2,4,5,6]. If continues intake of high fluoride (>1.5 water can severely cause dental and skeletal fluorosis. The investigated area people majorly depend on groundwater for drinking purposes and fluoride concentration ranged from 0.2 to 7.4 mg/L with mean concentration of 2.7 mg/L and data was compared with WHO guidelines for drinking purposes. Overall, data reveals that the 57% of groundwater samples data was not safe for drinking purposes. Therefore, distribution of fluoride in the groundwater of Medak region in Telangana was suggested to intake drinking water, which are below level of fluoride concentration in the groundwater and take care about health implications.

  3. Parental preference for fluoride varnish: a new concept in a rapidly developing nation

    Directory of Open Access Journals (Sweden)

    Hendaus MA

    2016-07-01

    Full Text Available Mohamed A Hendaus,1,2 Hibaq A Jama,1 Faisal J Siddiqui,1,3 Sohair A Elsiddig,1 Ahmed H Alhammadi1,2 1Department of Pediatrics, General Academic Pediatrics Section, Hamad Medical Corporation, Doha, 2Department of Clinical Pediatrics, Weill Cornell Medical College, 3Pediatric Residency Program, Hamad Medical Corporation, Doha, Qatar Objective: The objective of this study was to investigate parental preference for fluoride varnish in a country where the average percentage of dental caries in young children is up to ~73%. Consequently, the aim of this study, despite being a pilot, was to create a nationwide project in the State of Qatar to promote oral health in children. Methods: A cross-sectional perspective study was conducted at Hamad Medical Corporation in Qatar. Parents of children aged ≤5 years were offered an interview survey. A total of 200 questionnaires were completed (response rate =100%. The study was conducted between December 1, 2014 and March 30, 2015, and included all children aged >1 year and <5 years who came to the outpatient clinics for well-child and sick visits. We also included children who were admitted to the inpatient wards. Results: The mean age of participant children was 2.8±1.1 years. When inquiring regarding parents’ knowledge and awareness of dental health, we found that >90% of families were aware that dental health affects the health of the whole body. The study showed that ~70% of parents were not aware of the existence of fluoride varnish, but would allow a health provider to apply fluoride varnish. Furthermore, ~80% of parents would not stop brushing their child’s teeth and would not skip dentist appointments if varnish was to be applied. Approximately 40% of parents conveyed some concerns regarding the safety of fluoride varnish, despite being considered as a new concept. The main concern was that the child might swallow some of the fluoride. Another important concern expressed by parents was the

  4. Saliva and dental erosion

    Directory of Open Access Journals (Sweden)

    Marília Afonso Rabelo Buzalaf

    2012-10-01

    Full Text Available Dental erosion is a multifactorial condition. The consideration of chemical, biological and behavioral factors is fundamental for its prevention and therapy. Among the biological factors, saliva is one of the most important parameters in the protection against erosive wear. Objective: This review discusses the role of salivary factors on the development of dental erosion. Material and Methods: A search was undertaken on MeDLINe website for papers from 1969 to 2010. The keywords used in the research were "saliva", "acquired pellicle", "salivary flow", "salivary buffering capacity" and "dental erosion". Inclusion of studies, data extraction and quality assessment were undertaken independently and in duplicate by two members of the review team. Disagreements were solved by discussion and consensus or by a third party. Results: Several characteristics and properties of saliva play an important role in dental erosion. Salivary clearance gradually eliminates the acids through swallowing and saliva presents buffering capacity causing neutralization and buffering of dietary acids. Salivary flow allows dilution of the acids. In addition, saliva is supersaturated with respect to tooth mineral, providing calcium, phosphate and fluoride necessary for remineralization after an erosive challenge. Furthermore, many proteins present in saliva and acquired pellicle play an important role in dental erosion. Conclusions: Saliva is the most important biological factor affecting the progression of dental erosion. Knowledge of its components and properties involved in this protective role can drive the development of preventive measures targeting to enhance its known beneficial effects.

  5. Metabolomic Effects of Xylitol and Fluoride on Plaque Biofilm in Vivo

    OpenAIRE

    Takahashi, N.; Washio, J.

    2011-01-01

    Dental caries is initiated by demineralization of the tooth surface through acid production from sugar by plaque biofilm. Fluoride and xylitol have been used worldwide as caries-preventive reagents, based on in vitro-proven inhibitory mechanisms on bacterial acid production. We attempted to confirm the inhibitory mechanisms of fluoride and xylitol in vivo by performing metabolome analysis on the central carbon metabolism in supragingival plaque using the combination of capillary electrophores...

  6. A three-year clinical comparison of a sodium monofluorophosphate dentifrice with sodium fluoride dentifrices on dental caries in children.

    Science.gov (United States)

    Lu, K H; Ruhlman, C D; Chung, K L; Sturzenberger, O P; Lehnhoff, R W

    1987-01-01

    This study compared the anticaries effects of these three fluoride-containing dentifrices: 1100 ppm F as NaF (positive control); 2800 ppm F as SMFP; and 2800 ppm F as NaF. The group using the 2800 SMFP dentifrice showed no significant differences in DMFS or DMFT, compared to the positive control, at anytime during the study. This indicated that higher levels of sodium monofluorophosphate in a dentifrice offer no advantage in caries protection over the conventional level of sodium fluoride, 1100 ppm F.

  7. A systematic review of dental disease management in cancer patients

    DEFF Research Database (Denmark)

    Hong, Catherine H L; Hu, Shijia; Haverman, Thijs

    2018-01-01

    INTRODUCTION: This systematic review aims to update on the prevalence of odontogenic-related infections and the efficacy of dental strategies in preventing dental-related complications in cancer patients since the 2010 systematic review. REVIEW METHOD: A literature search was conducted in the dat....../treatment protocols. The use of chlorhexidine, fluoride mouth rinses as well as composite resin, resin-modified glass ionomer cement (GIC), and amalgam restorations over conventional GIC in post head and neck radiation patients who are compliant fluoride users is recommended....

  8. Moderator material for neutrons and use of said material

    International Nuclear Information System (INIS)

    Hiismaeki, P.; Auterinen, I.

    1994-01-01

    The invention concerns a moderator material used for mediation of high-velocity neutrons, in particular of fission neutrons, to epithermal neutrons. The principal components of the moderator material are aluminum fluoride and aluminum metal, which have been formed into a dense composite substantially free of pores, wherein the material contains 20-50 percent-vol. of aluminum metal and 80-50 percent-vol. aluminum fluoride. Further, the use of the moderator material in accordance with the invention in neutron capture therapy of cancer tumours is described, such as in boron neutron capture therapy (BNCT)

  9. Estimation of fluoride concentration in drinking water and common beverages in United Arab Emirates (UAE).

    Science.gov (United States)

    Walia, Tarun; Abu Fanas, Salem; Akbar, Madiha; Eddin, Jamal; Adnan, Mohamad

    2017-07-01

    To assess fluoride concentration in drinking water which include tap water of 4 emirates - Abu Dhabi, Dubai, Sharjah and Ajman plus bottled water, commonly available soft drinks & juices in United Arab Emirates. Five different samples of tap water collected from each of the four emirates of UAE: Ajman, Sharjah, Abu Dhabi and Dubai; twenty-two brands of bottled water and fifteen brands of popular cold beverages, purchased from different supermarkets in U.A.E were tested using ion selective electrode method and the fluoride concentration was determined. The mean fluoride content of tap water samples was 0.14 mg F/L with a range of 0.04-0.3 mg F/L; with Ajman tap water samples showing the highest mean fluoride content of 0.3 mg F/L. The mean fluoride content for both bottled drinking water and beverages was 0.07 mg F/L with a range of 0.02-0.50 mg F/L and 0.04-0.1 mg F/L respectively. Majority (68.2%) of the bottled water are produced locally within U.A.E while a few (31.8%) are imported. The tap water, bottled water and beverages available in U.A.E show varying concentrations of fluoride, however none showed the optimal level necessary to prevent dental caries. Dental professionals in U.A.E should be aware of the fluoride concentrations before prescribing fluoride supplements to children.

  10. Diagnostic and Preventive Approaches for Dental Caries in Children: A Review

    Directory of Open Access Journals (Sweden)

    Shahryar Karami

    2017-04-01

    Full Text Available Context Oral health status plays an essential role in human health. Recently, enhancement in oral health caries has been noted in both developed and developing countries. Dental caries is still very common among children. Screening and preventive interventions is necessary. The aim of this study was to review the diagnostic and preventive approaches for dental caries in children. Evidence Acquisition Searching PubMed, Medline, the Cochrane Library (for 5 recent years from 2011 - 2016, and reference lists for keywords and phrases such as “dental caries in children” and prevention and diagnosis, we included trials and controlled observational studies regarding the diagnosis and preventive techniques for dental caries in children. Results We found no study demonstrating the effects of screening by primary care providers on clinical outcomes. In a cohort study, pediatrician examination associated with a sensitivity of 0.76 was reported to identify dental caries in children. The results of the new randomized trials that were confirmed by previous studies showed that the efficacy of fluoride varnish is more than no varnish in reduction of dental caries from 18% to 59%. Some of the trials regarding xylitol had no results regarding the effects on dental caries. New observational studies have shown an association between early childhood fluoride use and enamel fluorosis. There is no evidence on the accuracy of prediction instruments in primary care settings. Conclusions We found no direct evidence that reveals that screening by primary care clinicians can decrease early childhood caries. Previous evidences reviewed by the United State Preventive Services Task Force demonstrated that oral fluoride supplementation is effective in decreasing caries incidences, and recent evidences supported the effectiveness of fluoride varnish in higher-risk children.

  11. Combinatorial Effects of Aromatic 1,3-Disubstituted Ureas and Fluoride on In vitro Inhibition of Streptococcus mutans Biofilm Formation.

    Science.gov (United States)

    Kaur, Gurmeet; Balamurugan, P; Uma Maheswari, C; Anitha, A; Princy, S Adline

    2016-01-01

    Dental caries occur as a result of disequilibrium between acid producing pathogenic bacteria and alkali generating commensal bacteria within a dental biofilm (dental plaque). Streptococcus mutans has been reported as a primary cariogenic pathogen associated with dental caries. Emergence of multidrug resistant as well as fluoride resistant strains of S. mutans due to over use of various antibiotics are a rising problem and prompted the researchers worldwide to search for alternative therapies. In this perspective, the present study was aimed to screen selective inhibitors against ComA, a bacteriocin associated ABC transporter, involved in the quorum sensing of S. mutans. In light of our present in silico findings, 1,3-disubstituted urea derivatives which had better affinity to ComA were chemically synthesized in the present study for in vitro evaluation of S. mutans biofilm inhibition. The results revealed that 1,3-disubstituted urea derivatives showed good biofilm inhibition. In addition, synthesized compounds exhibited potent synergy with a very low concentration of fluoride (31.25-62.5 ppm) in inhibiting the biofilm formation of S. mutans without affecting the bacterial growth. Further, the results were supported by confocal laser scanning microscopy. On the whole, from our experimental results we conclude that the combinatorial application of fluoride and disubstituted ureas has a potential synergistic effect which has a promising approach in combating multidrug resistant and fluoride resistant S. mutans in dental caries management.

  12. Factors attributable for the prevalence of dental caries in Queensland children.

    Science.gov (United States)

    Do, Loc Giang; Ha, Diep Hong; Spencer, A John

    2015-10-01

    Dental caries is a multifactorial condition, prevention of which requires comprehensive understanding of both contextual and compositional determinants and their population impact. To investigate contextual and compositional factors associated with the prevalence of dental caries in children and to estimate the population impact of those factors. Children in one Australian state were selected through stratified random sampling selection in 2010-2011. Oral epidemiological examinations provided individual-level outcomes: prevalence of dental caries in the primary (among 5- to 8-year-olds) and permanent dentitions (9- to 14-year-olds). Socioeconomic status, oral health behaviours and practices and dietary patterns were explanatory factors at the individual-level, school-level and area-level fluoridation status. Three-level multilevel multivariable models were sequentially specified for the prevalence of dental caries to estimate prevalence ratios (PR) associated with explanatory factors, adjusting for covariates and between- and within-group variances. Population attributable fraction (PAF) was estimated as the population impact of the statistically significant explanatory factors. Data from 2214 5- to 8-year-olds and 3186 9- to 14-year-olds from 207 schools in 16 areas were analysed. The prevalence of dental caries in the primary and the permanent dentitions was 47.1% (43.9-50.4) and 38.8% (36.1-41.6), respectively. The highest prevalence of dental caries was observed in the nonfluoridated areas. In bivariate associations, factors at three levels were associated with prevalence of dental caries. In the full models, children in the nonfluoridated areas had significantly higher prevalence of dental caries [PR for the primary: 1.29 (1.11-1.50); PR for the permanent 1.49 (1.01-2.21)] compared with children in fluoridated areas, controlling for other factors. PAF estimates indicated that lack of water fluoridation attributed to 21% and 31% of primary and permanent dental

  13. Physical properties and compatibility with dental stones of current alginate impression materials.

    Science.gov (United States)

    Murata, H; Kawamura, M; Hamada, T; Chimori, H; Nikawa, H

    2004-11-01

    This study examined physical properties and compatibility with dental stones of two types of alginate impression materials. Five powder-type alginate impression materials (Alginoplast EM, Aroma Fine, Algiace Z, Coe Alginate, Jeltrate Plus) and a paste-type alginate impression material (Tokuso AP-1) were used. The dynamic viscosity immediately after mixing was measured by means of a controlled-stress rheometer. The gelation times were determined according to Japanese Industrial Standards (JIS) T6505, and recovery from deformation, strain in compression and compressive strength were determined according to the International Organization for Standardization (ISO) specification 1563. Detail reproduction and surface roughness of type III dental stones (New Plastone, New Sunstone) and a type IV dental stone (Die Stone) were evaluated using a ruled test block as specified in the ISO specification 1563 and a profilometer, respectively. The alginate impression materials evaluated in this study were all in compliance with the ISO specification 1563 and JIS T6505. The alginate impression materials had similar mechanical properties after gelation, whilst a wide range of dynamic viscosity immediately after being mixed, gelation times and compatibility with dental stones were found among the materials. The paste-type material had a higher dynamic viscosity and a shorter gelation time than the powder-type materials. The best surface quality was obtained with the paste-type material/type III dental stone cast combinations. The materials should be selected in consideration of initial flow, setting characteristics and compatibility with dental stones. The results suggested that a paste-type material would better meet the requirements of an alginate impression material.

  14. The Crisis at Christmas Dental Service: a review of an annual volunteer-led dental service for homeless and vulnerably housed people in London.

    Science.gov (United States)

    Doughty, J; Stagnell, S; Shah, N; Vasey, A; Gillard, C

    2018-01-01

    Background The UK charity Crisis originated in 1967 as a response to the increasing numbers of homeless people in London, and the first Crisis at Christmas event for rough sleepers was established in 1971. Since then, Crisis has provided numerous services over the Christmas period to the most vulnerable members of society. One of these is the Crisis at Christmas Dental Service (CCDS) which provides emergency and routine dental care from 23-29 of December each year. The charity is entirely dependent on voluntary staffing and industry donations including materials and facilities. This paper aims to assess the impact of the service over the last six years of clinical activity from 2011-2016.Method Anonymised data were collected from the annual CCDS delivered over the last six consecutive years. Services included: dental consultations; oral hygiene instruction; scale and polishes; permanent fillings; extractions; and fluoride varnish applications. In addition, anonymised patient feedback was collected after each dental attendance.Results On average, 80-85% of the patients were male and the majority were between 21 and 60 years of age. The most common nationality was British (46%). Over the six-year data collection period intervention treatments (restorations and extractions) remained fairly consistent, while the number of fluoride varnish applications and oral hygiene instruction have increased. The majority of patients reported positive satisfaction with their treatment and would have recommended the service to others. Approximately 75% of patients did not regularly attend a dentist outside of Crisis and a similar proportion were given information on where to access year round dental services for homeless people in London. The majority of dental volunteers felt that they enjoyed the experience and would consider volunteering again for Crisis in the future.Conclusion The Crisis at Christmas Dental Service has emerged as a valuable asset to the portfolio of resources

  15. A useful and non-invasive microanalysis method for dental restoration materials

    Science.gov (United States)

    Hosoki, M.; Satsuma, T.; Nishigawa, K.; Takeuchi, H.; Asaoka, K.

    2012-12-01

    The elemental analysis of intraoral dental restorations provides considerable information for the treatment of dental metal allergy. Elemental analyses require specific instruments and complicated procedures, so this examination is not commonly carried out in private dental clinics. We describe a novel, simple and useful micro-analytical method for dental metal restorations. Micro metal dust was obtained by polishing the surface of restorative metal material with an unused silicone point (SUPER-SNAP). The metal dust on the silicone point was then rubbed onto adhesive tape, and this tape was covered with polyethylene film. The amount of metal dust material was film. Three types of dental metal alloy materials of known components were examined. The results of elementary analyses were compared with the specifications provided by the manufacturer. The same procedure was carried out for three dental metal restorations of an adult female volunteer in vivo. The results of elemental analyses for five alloy materials exactly matched the product specification. Three metal samples obtained from intraoral restoration were also available for elemental analyses. The distinct advantage of this method is that it enables sample extraction without an invasive effect for the restoration. The metal sample is in a polyethylene film, so it is easy to mail it for inspection at specialist institutes yet it can be also be used in general dental clinics.

  16. Method for identifying particulate fluoride compounds

    Energy Technology Data Exchange (ETDEWEB)

    Tufts, B J

    1960-01-01

    A method is described for identifying particulates containing fluorides and other complex fluorine compounds such as fluorosilicate in samples collected on membrane filters. The filter is treated with lead chloride to precipitate lead chlorofluoride at each fluoride-containing spot. This microspot is identified by examination in a light microscope. Sulfate and phosphate, which also precipitate if present, can be distinguished and do not interfere. Calibrations are given for the fluorides and the more insoluble salts, relating the original particle size to the reaction site size. Thus, the mass of the particles can be calculated. Results of some field tests in an area of fluoride pollution are given, and compared with standard testing procedures.

  17. Study of the luminescence properties of dental materials for their use in accidental dosimetry

    International Nuclear Information System (INIS)

    Veronese, Ivan; Cantone, Marie C.; Guzzi, Gianpaolo

    2008-01-01

    Full text: The current social and political situation in many world areas and the increasing hostilities between countries and cultures have accentuated the risk of a malicious use of ionising radiations. Terrorist attacks with the intentional disseminations of radioactive materials in urban settlements may involve a large number of persons, and a rapid estimation of the severity of the exposure is required for undertaking suitable protective actions and supporting decision making. Promising methodologies for a prompt dose evaluation, are those exploiting the luminescence and dosimetric properties of objects and materials which can be easily found in the contaminated area. Among these objects, dental materials have the advantage to be on contact with human body and they could therefore represent individual dosimeters in case of accidental exposure to ionising radiation. The interest in the use of dental ceramics for dosimetric purposes dates back to late 1970, however, it is only through the use of high-sensitive experimental techniques and instrumentation today available, that the potentiality of such materials as accidental dosimeters can be exploited. Moreover, innovative materials are being continuously introduced into the market, containing new additives and pigments with peculiar optical properties. In this study, Thermally Stimulated Luminescence (TSL) and Optically Stimulated Luminescence (OSL) techniques are applied to investigate the luminescence and dosimetric properties of several dental materials, including resins, glass and feldspatic ceramics, and also zirconia and alumina based ceramics, being their use widely increased in the recent years in substitution of metal cores. (author)

  18. Fluoride concentration in urine after silver diamine fluoride application on tooth enamel

    Science.gov (United States)

    Sari, D. L.; Bahar, A.; Gunawan, H. A.; Adiatman, M.; Rahardjo, A.; Maharani, D. A.; Toptanci, I. R.; Yavuz, I.

    2017-08-01

    Silver Diammine Fluoride (SDF), which contains fluoride, is known to inhibit tooth enamel demineralization and increase fluoride concentrations in saliva and urine. The aim of this study is to analyze the fluoride concentration in urine after application of SDF on tooth enamel. Urine from four subjects was collected prior to, 30 minutes after, and two and three hours after the application of SDF, and an ion-selective electrode was used to measure the fluoride concentrations. There was no significant difference between time 1 and time 2, time 1 and time 3, time 1 and time 4, time 2 and 3 (p > 0.05), and there was a significant difference between time 2 and time 4 as well as time 3 and time 4 (p < 0.05). There was a decrease in the concentration of fluoride ions in urine from the baseline to 30 minutes after application, and an increase from baseline to two and three hours after the application of SDF.

  19. Efficacy of silver diamine fluoride for Arresting Caries Treatment.

    NARCIS (Netherlands)

    Yee, R.T.F.; Holmgren, C.J.; Mulder, J.; Lama, D.; Walker, D.; Palenstein Helderman, W.H. van

    2009-01-01

    Arresting Caries Treatment (ACT) has been proposed to manage untreated dental caries in children. This prospective randomized clinical trial investigated the caries-arresting effectiveness of a single spot application of: (1) 38% silver diamine fluoride (SDF) with tannic acid as a reducing agent;

  20. Crevice corrosion of alloy 22 in fluoride and chloride containing solutions

    International Nuclear Information System (INIS)

    Carranza, Ricardo M.; Rodriguez, Martin A.

    2005-01-01

    Alloy 22 (N06022) is highly resistant to localized corrosion. Alloy 22 may be susceptible to crevice corrosion in pure chloride (Cl - ) solutions under aggressive environmental conditions. The effect of the fluoride (F - ) on the susceptibility to crevice corrosion induced by chloride ions is still not well established. The objective of the present work was to explore the crevice corrosion resistance of this alloy to different mixtures of fluorides and chlorides. Cyclic potentiodynamic polarization (CPP) tests were conducted in deaerated aqueous solutions of pure halide ions and also in different mixtures of chloride and fluoride at 90 C degrees and pH 6. The range of chloride concentration [Cl - ] was 0.001 M ≤ [Cl - ] ≤ 1 M and the range of molar fluoride to chloride ratio [F - ]/[Cl - ] was 0.1≤ [F - ]/[Cl - ] ≤ 10. Results showed that Alloy 22 was susceptible to crevice corrosion in all the pure chloride solutions but not in the pure fluoride solutions. A molar ratio [F - ]/[Cl - ] ranging from 5 to 10 was required for the inhibition of crevice corrosion to be complete in the halide mixtures. A moderate or nil inhibitive effect was observed for molar ratios [F - ]/[Cl - ] [es

  1. Fluoride contamination of groundwater and health implications in ...

    African Journals Online (AJOL)

    The arid climate of the region, the granitic rocks and the low freshwater exchange due to periodical drought conditions are responsible for the higher incidence of fluorides in the groundwater resource. The people dependent on groundwater resources in the area are prone to dental fluorosis and mild skeletal fluorosis.

  2. Fluoride removal from double four-membered ring (D4R) units in As-synthesized Ge-containing zeolites

    KAUST Repository

    Liu, Xiaolong

    2011-11-22

    Fluoride anions can be removed from the framework of as-prepared Ge-containing zeolites ITQ-13 and ITQ-17 without modification of the crystallinity and crystal habit. By contrast to all-silica ITQ-13 for which fluoride could not get out from D4R units, F is completely removed from Ge rich zeolites, even from D4R cages. This has been explained by the relaxing effect of germanium, making F less necessary for the stabilization of the small D4R units. Si/Ge ratios are similar in as-prepared and treated zeolites, indicating that the framework composition is not affected by the removal of anions. The fluoride-free zeolites possess XRD patterns similar to those of the as-made solids but their 29Si NMR spectra are significantly different, revealing the sensitivity of the method to the environment of silicon atoms in the framework. The extent of fluoride that can be removed from D4R units depends not only on the framework Ge content but also on the zeolite topology: for similar contents, F is much more easily eliminated from ITQ-17 than from ITQ-13. © 2011 American Chemical Society.

  3. Geochemistry of fluoride in the Black Creek aquifer system of Horry and Georgetown Counties, South Carolina--and its physiological implications

    Science.gov (United States)

    Zack, Allen L.

    1980-01-01

    High concentrations of fluoride in ground-water supplies in certain areas of Horry and Georgetown Counties, S.C., have been the cause of dental fluorosis (tooth mottling) among persons who have lived in these areas and have ingested the water as children. Geochemical evidence and laboratory experiments demonstrate that fluorapatite in the form of fossil shark teeth is the source of fluoride, and that the fluoride ions are liberated to the ground-water system through anion exchange, rather than by dissolution. Calcite-cemented quartz sand in the upper third of the Black Creek Formation of Late Cretaceous age contains the fossil shark teeth. As ground water progresses downdip, the calcite matrix dissolves and hydrolyzes, releasing bicarbonate, hydroxyl, and calcium ions. The calcium ions are immediately exchanged for sodium ions adsorbed on sodium-rich clays, and the bicarbonate ions accumulate. As the shark teeth are exposed, the hydroxyl ions in solution exchange with fluoride ions on fluorapatite surfaces. Experiments using fossil shark teeth show that sodium chloride in solution inhibits the rate of exchange of fluoride ions from tooth surfaces for hydroxyl ions in solution. The amount of fluoride removed from water and exchanged for hydroxyl ions in the presence of pure hydroxylapatite (hog teeth) was greater in saline water than in freshwater.

  4. The effect of CO2 laser irradiation plus fluoride dentifrice on the inhibition of secondary caries on root surfaces adjacent to glass ionomer cement or composite resin restorations

    International Nuclear Information System (INIS)

    Rodrigues, S R; Moraes, M; Youssef, M N; De Souza-Zaroni, W C; Hanashiro, F S; Brugnera Junior, A; Nobre-dos-Santos, M

    2016-01-01

    Although the cariostatic effects of CO 2 laser on the root surface have been shown, there is scarce information regarding its effects on root secondary caries. The objective of this research was to investigate the effect of the association of CO 2 laser and a fluoride dentifrice on the inhibition of secondary caries on root surfaces adjacent to composite-resin or glass-ionomer-cement restorations. Dental blocks of human roots were divided into two groups: composite resin (CR) or glass ionomer cement (GIC). Subsequently, the blocks were divided into four subgroups (n  =  10): C, non-fluoride dentifrice; FD, fluoride dentifrice; L, CO 2 laser with an energy density of 6.0 J cm −2   +  non-fluoride dentifrice; and L  +  FD, CO 2 laser  +  fluoride dentifrice. The blocks were subjected to pH cycling to simulate a high cariogenic challenge. Dental demineralization around the restorations was quantified by microhardness analysis. The results were subjected to analysis of variance (ANOVA) and the Tukey–Kramer test (p  ⩽  0.05). As for mineral loss, it can be observed that all the groups that were treated with a fluoride dentifrice and laser, used alone or not, were statistically similar and superior to the RC–C group. It was concluded that CO 2 laser irradiation and a fluoride dentifrice used alone or combined with each other are efficient surface treatments for preventing secondary root caries, regardless of the restorative material used. (paper)

  5. Antibacterial Effect of Silver Diamine Fluoride on Cariogenic Organisms.

    Science.gov (United States)

    Lou, Yali; Darvell, Brain W; Botelho, Michael G

    2018-05-01

    To screen the possible antimicrobial activity of a range of clinically used, silver-based compounds on cariogenic organisms: silver diamine fluoride (SDF), silver fluoride, and silver nitrate. Preliminary screening disk-diffusion susceptibility tests were conducted on Mueller-Hinton agar plates inoculated with Streptococcus mutans, Lactobacillus acidophilus, and Actinomyces naeslundii, organisms known to be cariogenic. In order to identify which component of the silver compounds was responsible for any antibacterial (AB) effect, and to provide controls, the following were also investigated at high and low concentrations: sodium fluoride, ammonium fluoride, ammonium chloride, sodium fluoride, sodium chloride, and sodium nitrate, as well as deionized water as control. A volume of 10 pL of a test solution was dispensed onto a paper disk resting on the inoculated agar surface, and the plate incubated anaerobically at 37°C for 48 hours. The zones of inhibition were then measured. Silver diamine fluoride, silver fluoride, silver nitrate, and ammonium fluoride had significant AB effect (p effect at low concentration; the remaining other compounds had no effect. Silver ions appear to be the principal AB agent at both high and low concentration; fluoride ions only have an AB effect at high concentration, while ammonium, nitrate, chloride and sodium ions have none. The anticaries effect of topical silver solutions appears restricted to that of the silver ions. Silver compounds, such as SDF, silver fluoride, and silver nitrate have AB effect against cariogenic organisms and these may have clinical impact in arresting or preventing dental decay. Sodium fluoride did not have AB effect under the conditions tested.

  6. Evaluation of pH at the Bacteria–Dental Cement Interface

    Science.gov (United States)

    Mayanagi, G.; Igarashi, K.; Washio, J.; Nakajo, K.; Domon-Tawaraya, H.; Takahashi, N.

    2011-01-01

    Physiochemical assessment of the parasite-biomaterial interface is essential in the development of new biomaterials. The purpose of this study was to develop a method to evaluate pH at the bacteria-dental cement interface and to demonstrate physiochemical interaction at the interface. The experimental apparatus with a well (4.0 mm in diameter and 2.0 mm deep) was made of polymethyl methacrylate with dental cement or polymethyl methacrylate (control) at the bottom. Three representative dental cements (glass-ionomer, zinc phosphate, and zinc oxide-eugenol cements) were used. Each specimen was immersed in 2 mM potassium phosphate buffer for 10 min, 24 hrs, 1 wk, or 4 wks. The well was packed with Streptococcus mutans NCTC 10449, and a miniature pH electrode was placed at the interface between bacterial cells and dental cement. The pH was monitored after the addition of 1% glucose, and the fluoride contained in the cells was quantified. Glass-ionomer cement inhibited the bacteria-induced pH fall significantly compared with polymethyl methacrylate (control) at the interface (10 min, 5.16 ± 0.19 vs. 4.50 ± 0.07; 24 hrs, 5.20 ± 0.07 vs. 4.59 ± 0.11; 1 wk, 5.34 ± 0.14 vs. 4.57 ± 0.11; and 4 wks, 4.95 ± 0.27 vs. 4.40 ± 0.14), probably due to the fluoride released from the cement. This method could be useful for the assessment of pH at the parasite-biomaterial interface. PMID:21933936

  7. Combinatorial effects of aromatic 1,3 – disubstituted ureas and fluoride on in vitro inhibition of Streptococcus mutans biofilm formation

    Directory of Open Access Journals (Sweden)

    Gurmeet eKaur

    2016-06-01

    Full Text Available Dental caries occurs as a result of disequilibrium between acid producing pathogenic bacteria and alkali generating commensal bacteria within a dental biofilm (dental plaque. S. mutans has been reported as a primary cariogenic pathogen associated with dental caries. Emergence of multidrug resistant as well as fluoride resistant strains of Streptococcus mutans due to over usage of various antibiotics is a rising problem and prompted the researchers worldwide to search for alternative therapies. In this perspective, the present study was aimed to screen selective inhibitors against ComA, a bacteriocin associated ABC transporter, involved in the quorum sensing of S. mutans. In light of our previous in silico findings, 1,3- disubstituted urea derivatives which had better affinity to ComA were chemically synthesized in the present study for in vitro evaluation of S. mutans biofilm inhibition. The results revealed that 1,3- disubstituted urea derivatives showed good biofilm inhibition. In addition, the synthesized compounds exhibited potent synergy with a very low concentration of fluoride (31.25 ppm to 62.5 ppm in inhibiting the biofilm formation of S. mutans without affecting the bacterial growth. Further, the results were confirmed by confocal laser scanning microscopy. On the whole, from our experimental results we conclude that the combinatorial application of fluoride and disubstituted ureas has a potential synergistic effect which has a promising approach in combating multidrug resistant and fluoride resistant S. mutans in dental caries management.

  8. Wear measurement of dental tissues and materials in clinical studies: A systematic review.

    Science.gov (United States)

    Wulfman, C; Koenig, V; Mainjot, A K

    2018-06-01

    This study aims to systematically review the different methods used for wear measurement of dental tissues and materials in clinical studies, their relevance and reliability in terms of accuracy and precision, and the performance of the different steps of the workflow taken independently. An exhaustive search of clinical studies related to wear of dental tissues and materials reporting a quantitative measurement method was conducted. MedLine, Embase, Scopus, Cochrane Library and Web of Science databases were used. Prospective studies, pilot studies and case series (>10 patients), as long as they contained a description of wear measurement methodology. Only studies published after 1995 were considered. After duplicates' removal, 495 studies were identified, and 41 remained for quantitative analysis. Thirty-four described wear-measurement protocols, using digital profilometry and superimposition, whereas 7 used alternative protocols. A specific form was designed to analyze the risk of bias. The methods were described in terms of material analyzed; study design; device used for surface acquisition; matching software details and settings; type of analysis (vertical height-loss measurement vs volume loss measurement); type of area investigated (entire occlusal area or selective areas); and results. There is a need of standardization of clinical wear measurement. Current methods exhibit accuracy, which is not sufficient to monitor wear of restorative materials and tooth tissues. Their performance could be improved, notably limiting the use of replicas, using standardized calibration procedures and positive controls, optimizing the settings of scanners and matching softwares, and taking into account unusable data. Copyright © 2018 The Academy of Dental Materials. Published by Elsevier Inc. All rights reserved.

  9. Nano materials for Medical and Dental Applications

    International Nuclear Information System (INIS)

    Yub Kwon, T.; Oh, D.S.; Narayanan, R.

    2015-01-01

    Welcome to this special issue. Nano science and nano technology concepts are applicable across all fields of science and a more widespread application of nano materials and nano technologies is imminent or already occurring in many areas, including health care. Today is scientists take those cutting-edge technologies and concepts and apply them to medicine and dentistry. They are finding a wide variety of ways to make medical and dental materials at the nano scale to take advantage of their enhanced physical and biological properties.The purpose of this special issue is to publish high-quality research papers as well as review articles addressing recent advances in the field of nano materials for medical and dental applications. A particular interest is given to papers exploring or discussing nano materials and nano technologies related to delivery system, bonding substitutes, and surface modification techniques applicable in these areas. For this special issue, several investigators were invited to contribute original research findings that can stimulate continuing efforts to understand the cutting-edge applications of nano materials in medicine and dentistry.

  10. Sirt1 overexpression suppresses fluoride-induced p53 acetylation to alleviate fluoride toxicity in ameloblasts responsible for enamel formation.

    Science.gov (United States)

    Suzuki, Maiko; Ikeda, Atsushi; Bartlett, John D

    2018-03-01

    Low-dose fluoride is an effective caries prophylactic, but high-dose fluoride is an environmental health hazard that causes skeletal and dental fluorosis. Treatments to prevent fluorosis and the molecular pathways responsive to fluoride exposure remain to be elucidated. Previously we showed that fluoride activates SIRT1 as an adaptive response to protect cells. Here, we demonstrate that fluoride induced p53 acetylation (Ac-p53) [Lys379], which is a SIRT1 deacetylation target, in ameloblast-derived LS8 cells in vitro and in enamel organ in vivo. Here we assessed SIRT1 function on fluoride-induced Ac-p53 formation using CRISPR/Cas9-mediated Sirt1 knockout (LS8 Sirt/KO ) cells or CRISPR/dCas9/SAM-mediated Sirt1 overexpressing (LS8 Sirt1/over ) cells. NaF (5 mM) induced Ac-p53 formation and increased cell cycle arrest via Cdkn1a/p21 expression in Wild-type (WT) cells. However, fluoride-induced Ac-p53 was suppressed by the SIRT1 activator resveratrol (50 µM). Without fluoride, Ac-p53 persisted in LS8 Sirt/KO cells, whereas it decreased in LS8 Sirt1/over . Fluoride-induced Ac-p53 formation was also suppressed in LS8 Sirt1/over cells. Compared to WT cells, fluoride-induced Cdkn1a/p21 expression was elevated in LS8 Sirt/KO and these cells were more susceptible to fluoride-induced growth inhibition. In contrast, LS8 Sirt1/over cells were significantly more resistant. In addition, fluoride-induced cytochrome-c release and caspase-3 activation were suppressed in LS8 Sirt1/over cells. Fluoride induced expression of the DNA double strand break marker γH2AX in WT cells and this was augmented in LS8 Sirt1/KO cells, but was attenuated in LS8 Sirt1/over cells. Our results suggest that SIRT1 deacetylates Ac-p53 to mitigate fluoride-induced cell growth inhibition, mitochondrial damage, DNA damage and apoptosis. This is the first report implicating Ac-p53 in fluoride toxicity.

  11. Fluoride export (FEX) proteins from fungi, plants and animals are 'single barreled' channels containing one functional and one vestigial ion pore

    Science.gov (United States)

    Berbasova, Tetyana; Nallur, Sunitha; Sells, Taylor; Smith, Kathryn D.; Gordon, Patricia B.; Tausta, Susan Lori

    2017-01-01

    The fluoride export protein (FEX) in yeast and other fungi provides tolerance to fluoride (F-), an environmentally ubiquitous anion. FEX efficiently eliminates intracellular fluoride that otherwise would accumulate at toxic concentrations. The FEX homolog in bacteria, Fluc, is a ‘double-barreled’ channel formed by dimerization of two identical or similar subunits. FEX in yeast and other eukaryotes is a monomer resulting from covalent fusion of the two subunits. As a result, both potential fluoride pores are created from different parts of the same protein. Here we identify FEX proteins from two multicellular eukaryotes, a plant Arabidopsis thaliana and an animal Amphimedon queenslandica, by demonstrating significant fluoride tolerance when these proteins are heterologously expressed in the yeast Saccharomyces cerevisiae. Residues important for eukaryotic FEX function were determined by phylogenetic sequence alignment and functional analysis using a yeast growth assay. Key residues of the fluoride channel are conserved in only one of the two potential fluoride-transporting pores. FEX activity is abolished upon mutation of residues in this conserved pore, suggesting that only one of the pores is functional. The same topology is conserved for the newly identified FEX proteins from plant and animal. These data suggest that FEX family of fluoride channels in eukaryotes are ‘single-barreled’ transporters containing one functional pore and a second non-functional vestigial remnant of a homologous gene fusion event. PMID:28472134

  12. Parents' Attitude towards the Use of Fluorides and Fissure Sealants and its Effect on their Children's Oral Health.

    Science.gov (United States)

    Blumer, Sigalit; Ratson, Tal; Peretz, Benjamin; Dagon, Nurit

    To characterize the attitudes of Israeli parents towards caries preventive measures. participating parents completed a 21-item questionnaire on their demographics, dental history, attitudes and satisfaction from fluorides and fissure sealants. One hundred parents (average age 41.62±4.9 years, 85 females) participated. Most of the parents (88% of the mothers and 84% of the fathers) had an academic education. Most of the parents (54%) had a favorable attitude towards the use of fluoridated gels, while only 37% of them had a positive opinion regarding fluoridated water. The satisfaction levels were very high regarding fissure sealants, fluoridated mouth rinses and fluoridated gels (78.1%, 73.6% and 72.5% respectively). The satisfaction from fluoridated water was split almost equally (50.8% were 'pleased' and 49.2% 'not pleased'). The main source for parental oral health knowledge was the dentist (83%). Parents' attitude towards caries preventive measures was significantly correlated to their gender, dental experience, level of education and the number of children in the family. positive attitude towards caries preventive measures was found among parents with higher awareness for preventive oral health measures and among bigger families. Mothers were more positive about fissure sealants than fathers. Mothers with up to 12 years of education tended to have a positive opinion regarding water fluoridation.

  13. Amino acid derivative-mediated detoxification and functionalization of dual cure dental restorative material for dental pulp cell mineralization.

    Science.gov (United States)

    Minamikawa, Hajime; Yamada, Masahiro; Iwasa, Fuminori; Ueno, Takeshi; Deyama, Yoshiaki; Suzuki, Kuniaki; Yawaka, Yasutaka; Ogawa, Takahiro

    2010-10-01

    Current dental restorative materials are only used to fill the defect of hard tissues, such as dentin and enamel, because of their cytotoxicity. Therefore, exposed dental pulp tissues in deep cavities must be first covered by a pulp capping material like calcium hydroxide to form a layer of mineralized tissue. However, this tissue mineralization is based on pathological reaction and triggers long-lasting inflammation, often causing clinical problems. This study tested the ability of N-acetyl cysteine (NAC), amino acid derivative, to reduce cytotoxicity and induce mineralized tissue conductivity in resin-modified glass ionomer (RMGI), a widely used dental restorative material having dual cure mechanism. Rat dental pulp cells were cultured on untreated or NAC-supplemented RMGI. NAC supplementation substantially increased the percentage of viable cells from 46.7 to 73.3% after 24-h incubation. Cell attachment, spreading, proliferative activity, and odontoblast-related gene and protein expressions increased significantly on NAC-supplemented RMGI. The mineralization capability of cells, which was nearly suppressed on untreated RMGI, was induced on NAC-supplemented RMGI. These improved behaviors and functions of dental pulp cells on NAC-supplemented RMGI were associated with a considerable reduction in the production of intracellular reactive oxygen species and with the increased level of intracellular glutathione reserves. These results demonstrated that NAC could detoxify and functionalize RMGIs via two different mechanisms involving in situ material detoxification and antioxidant cell protection. We believe that this study provides a new approach for developing dental restorative materials that enables mineralized tissue regeneration.

  14. A simple and colorimetric fluoride receptor and its fluoride-responsive organogel

    Energy Technology Data Exchange (ETDEWEB)

    Yu Xudong, E-mail: 081022009@fudan.edu.cn [College of Science, Hebei University of Science and Technology, Yuhua Road 70, Shijiazhuang 050080 (China); Li Yajuan [College of Science, Hebei University of Science and Technology, Yuhua Road 70, Shijiazhuang 050080 (China); Yin Yaobing; Yu Decai [College of Science, Hebei University of Engineering, 199 South street of Guangming, Handan 056038 (China)

    2012-08-01

    In this paper, a new p-nitrophenylhydrozine-based anion receptor 1 containing cholesterol group had been designed and synthesized. It could selectively recognize fluoride among different anions tested with color changes from pale yellow to red for visual detection. Simultaneously, it could gel in cyclohexane, and the gel was also fluoride-responsive. When treated with TBAF (tetra-n-butylammonium fluoride), the gel could undergo gel-sol transition accompanied by color, morphology and surface changes. The binding mechanism had been investigated by UV-vis and {sup 1}HNMR (proton nuclear magnetic resonance spectra) titrations. From SEM (scanning electron microscope), SAXS (small-angle X-ray scattering), IR (Infrared Spectroscopy) and CA (contact angle) experiments, it was indicated that the addition of F{sup -} could destroy the molecule assembly of host 1 in the gel state, thus resulting in the gel-to-sol transition due to the binding site competition effect. To the best of our knowledge, this was the simplest fluoride-responsive organogel with high selectivity. Highlights: Black-Right-Pointing-Pointer A novel kind receptor for selective recognition of fluoride had been designed. Black-Right-Pointing-Pointer Its organogel was also fluoride-responsive. Black-Right-Pointing-Pointer This is the simplest fluoride-responsive organogel with high selectivity.

  15. Effects of the low-intensity laser therapy on the prevention of dental caries induced in rats; Efeitos da radiacao laser em baixa intensidade na prevencao de carie dental induzida em ratos

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, Karin Praia

    2004-07-01

    The purpose of this study was to investigate the effects of low intensity laser therapy, associated or not to an acidulated phosphate fluoride, on the prevention of dental caries induced in rats. It was used 40 wistar rats, female, weaned with 18 days, fed with a cariogenic diet during 48 days and inoculated orally with Streptococcus mutans by three consecutive days starting from the second day of the diet. On the fifth day of experiment the animals were divided into five groups: G{sub c} (control) the animas were no submitted to any treatment; G{sub L} (laser) irradiation with low power laser (GaAlAs, {lambda}=660 nm, P=30 mW, {delta}t=5 sec, 5 J/cm{sup 2}); G{sub F} (fluoride) topical application of acidulated phosphate fluoride (APF 1,23%) for four minutes; G{sub LF} (laser + fluoride) irradiation with low power laser followed by topical application of acidulated phosphate fluoride; G{sub FL} (fluoride + laser) topical application of acidulated phosphate fluoride followed by low power laser. The animals were sacrificed after 48 days; the molars were extracted and prepared to determine the dental caries lesions area by optical microscopy, enamel microhardness and analysis of the calcium and phosphorus ratio (Ca/P) by energy dispersive spectroscopy. The results were statistically analyzed by ANOVA (pdental caries areas for the group G{sub LF} was smaller than that for G{sub F} and G{sub FL} groups but no statistical difference was observed. There was no significant statistical difference between the microhardness of the G{sub C} and G{sub L} groups and among G{sub FL}, G{sub LF} and G{sub F} groups. Regarding to the calcium and phosphorus ratio, it was not observed significant statistical differences among the groups. These findings suggest that low-intensity laser radiation associated with acidulated phosphate fluoride reduces the caries area and could be an alternative in the prevention of the dental caries. (author)

  16. Profile of dental caries in teenagers in Mumbai City visiting Nair Hospital Dental College

    Directory of Open Access Journals (Sweden)

    Kulvinder Singh Banga

    2018-01-01

    Full Text Available Background: Witnessing the alarming rise and pattern of distribution of dental caries worldwide, the need of the hour is to take initiative in preventing the spread further. Aim: This survey was conducted to determine the occurrence of dental caries and its associated risk factors in teenagers of Mumbai city who visited Nair Hospital Dental College. Materials and Methods: The objective of the study was to analyze the current dietary habits, oral hygiene status, and the number of sugar exposures in teenagers by a questionnaire followed by clinical examination which was carried out using International Caries Detection and Assessment System (ICDAS II to detect the profile of dental caries. Statistical Analysis: The data obtained from the questionnaire and examination were analyzed using Chi-square test. Results: The survey showed that, out of the 300 teenagers examined, 67% visited the dentist only when they were symptomatic. Around 60% consumed sweets 2–3 times/day. A major percentage, 89%, consumed sweets irrespective of meal time and 52% consumed aerated drinks often. Only 16% used appropriate brushing techniques and 93% were not aware if their toothpaste was fluoridated. ICDAS II revealed that a total number of teeth requiring preventive treatment ranged from 8.3% to 14% and total number of teeth requiring definitive treatment ranged from 36% to 48%. It was found that tooth most commonly treated was 36 followed by tooth number 46 showing that the incidence of caries is higher in lower arch. Conclusion: Most of the teenagers had a high rate of sweet consumption in between meals and poor knowledge of brushing techniques, fluoridated toothpaste, interdental aids, and mouthrinses. ICDAS showed a high incidence of caries in teenagers, especially in the lower arch. ICDAS II showed good accuracy in differentiating between noncavitated and cavitated lesions which helps to provide an accurate treatment plan for teenagers so that it prevents the

  17. In Vitro and In Vivo Osteogenic Activity of Titanium Implants Coated by Pulsed Laser Deposition with a Thin Film of Fluoridated Hydroxyapatite

    Directory of Open Access Journals (Sweden)

    Luyuan Chen

    2018-04-01

    Full Text Available To enhance biocompatibility, osteogenesis, and osseointegration, we coated titanium implants, by krypton fluoride (KrF pulsed laser deposition, with a thin film of fluoridated hydroxyapatite (FHA. Coating was confirmed by scanning electron microscopy (SEM and scanning probe microscopy (SPM, while physicochemical properties were evaluated by attenuated reflectance Fourier transform infrared spectroscopy (ATR-FTIR. Calcium deposition, osteocalcin production, and expression of osteoblast genes were significantly higher in rat bone marrow mesenchymal stem cells seeded on FHA-coated titanium than in cells seeded on uncoated titanium. Implantation into rat femurs also showed that the FHA-coated material had superior osteoinductive and osseointegration activity in comparison with that of traditional implants, as assessed by microcomputed tomography and histology. Thus, titanium coated with FHA holds promise as a dental implant material.

  18. An Overview of Liquid Fluoride Salt Heat Transport Systems

    Energy Technology Data Exchange (ETDEWEB)

    Holcomb, David Eugene [ORNL; Cetiner, Sacit M [ORNL

    2010-09-01

    , and this report also describes more recently developed technologies such as dry gas seals. This report also provides a high-level, parametric evaluation of LSHT loop performance to allow general intercomparisons between heat-transport fluid options as well as provide an overview of the properties and requirements for a representative loop. A compilation of relevant thermophysical properties of useful fluoride salts is also included for salt heat transport systems. Fluoride salts can be highly corrosive depending on the container materials selected, the salt chemistry, and the operating procedures used. The report includes an overview of the state-of-the-art in reduction-oxidation chemistry control methodologies employed to minimize corrosion issues. Salt chemistry control technology, however, remains at too low a level of understanding for widespread industrial usage. Loop operational issues such as start-up procedures and system freeze-up vulnerability are also discussed. Liquid fluoride salts are a leading candidate heat transport medium for high-temperature applications. This report provides an overview of the current status of liquid salt heat transport technology. The report includes a high-level, parametric evaluation of liquid fluoride salt heat transport loop performance to allow intercomparisons between heat-transport fluid options as well as providing an overview of the properties and requirements for a representative loop. Much of the information presented here derives from the earlier molten salt reactor program and a significant advantage of fluoride salts, as high temperature heat transport media is their consequent relative technological maturity. The report also includes a compilation of relevant thermophysical properties of useful heat transport fluoride salts. Fluoride salts are both thermally stable and with proper chemistry control can be relatively chemically inert. Fluoride salts can, however, be highly corrosive depending on the container

  19. Comparative study of fluoride concentration in human serum and drinking water in fluorinated endemic and non endemic areas of pakistan

    International Nuclear Information System (INIS)

    Qayyum, M.; Ahmad, B.; Ahmad, M.

    2013-01-01

    For comparing the human blood serum and drinking water fluoride levels of subjects with dental fluorosis and bony deformities, this study is carried out with individuals ranging 8-17 age group fluorinated Sham Ki Bhatiyan, Punjab (endemic) and Queens Road, Lahore, Punjab (non-endemic) areas. Fluoride concentrations were determined using ion selective electrode methodology and statistically compared. Both the groups showed a significant difference (p < 0.05). Subjects from fluorotic area showed high concentration of fluoride in water and blood serum samples (mean value: 135.587+-77.435 and 2.765+-0.469 micro molL/sup -1/ in water and blood serum samples respectively) as compared to controls (mean value: 19.509+-2.432 and 2.364+- 0.667 micro molL -1). These findings indicate that serum and water fluoride concentrations have a significant positive dose response relationship with the prevalence of dental fluorosis in an area associated with high fluoride level in drinking water. (author)

  20. Increased Prevalence of Dental Fluorosis after Twenty Years

    DEFF Research Database (Denmark)

    Richards, Alan; Larsen, Mogens Joost; Maare, L.

    2006-01-01

    tooth types in children born and reared in an area with drinking water with (regularly monitored, naturally-occurring) fluoride concentrations of 1 ppm and compare with data recorded for a similar group of children examined in the same way and residing in the same area 20 years ago. Methods: Dental...... children, of similar ages, examined in the same area in 1984. Results: The prevalence and severity of fluorosis varied between tooth types so that the later in childhood the teeth are mineralized the higher the prevalence of dental fluorosis. When the data were compared to those collected 20 years...... in the (later formed) premolars and second molars. Conclusions: A significant increase in fluorosis prevalence has occurred over the last 20 years due to increased fluoride exposure of pre-school children. These findings may be explained by increased use of fluoride toothpaste by this age group from...

  1. Percepción de ingesta de flúor a través del cepillado dental en niños colombianos Perception of fluoride ingestion by dental brushing in Colombian children

    Directory of Open Access Journals (Sweden)

    Farith González Martínez

    2010-09-01

    Full Text Available Objetivo: describir la percepción de los padres sobre la ingesta de flúor a través del cepillado dental en los niños residentes en la ciudad de Cartagena de Indias, Colombia. Métodos: el universo del estudio lo constituyeron todos los padres residentes en la ciudad de Cartagena de Indias, con hijos en edades entre uno y cinco años. La muestra estuvo integrada por 420 individuos. Se utilizó un cuestionario estructurado, diligenciado por los participantes, con el cual se midieron tópicos relacionados con el uso de las cremas dentales a través del cepillado. Además se tuvieron en cuenta la edad, el género y el estrato socioeconómico. Los datos fueron analizados a través de pruebas de frecuencia; se asumieron intervalos de confianza al 95 %. Para encontrar significación estadística se utilizó la prueba de X². Resultados: el 88,0 % de los padres encuestados refiere usar el cepillado con crema dental. La edad promedio de cepillado es de 2,3 años (DE= 1,6. El 46 % se cepilla dos veces al día; el tipo de crema dental más usada es la de adultos. La mayoría de los encuestados afirma que los niños han ingerido la pasta durante el cepillado. Con respecto al análisis bivariado, se encontraron diferencias entre el cepillado con crema dental y la edad (p= 0,0001, y con el estrato (p= 0,04. Además, el tipo de crema dental con la edad, (p= 0,0001 y la cantidad de pasta utilizada con la edad (p= 0,0001 y el estrato (p= 0,01. Conclusión: se perciben hábitos poco favorables, asociados al cepillado con pasta dental, los cuales pueden ser responsables de la ingestión de cantidades de flúor consideradas nocivas para la salud.Objective: To describe the parents perception on the fluoride ingestion with the use of dental brushing in the children residents in the city of Cartagena de Indias. Methods: Study universe included al parents residents in the city above mentioned whose children were aged 1-5. Sample included 420 subjects. A structural

  2. Readability of pediatric health materials for preventive dental care

    Directory of Open Access Journals (Sweden)

    Riedy Christine A

    2006-11-01

    Full Text Available Abstract Background This study examined the content and general readability of pediatric oral health education materials for parents of young children. Methods Twenty-seven pediatric oral health pamphlets or brochures from commercial, government, industry, and private nonprofit sources were analyzed for general readability ("usability" according to several parameters: readability, (Flesch-Kincaid grade level, Flesch Reading Ease, and SMOG grade level; thoroughness, (inclusion of topics important to young childrens' oral health; textual framework (frequency of complex phrases, use of pictures, diagrams, and bulleted text within materials; and terminology (frequency of difficult words and dental jargon. Results Readability of the written texts ranged from 2nd to 9th grade. The average Flesch-Kincaid grade level for government publications was equivalent to a grade 4 reading level (4.73, range, 2.4 – 6.6; F-K grade levels for commercial publications averaged 8.1 (range, 6.9 – 8.9; and industry published materials read at an average Flesch-Kincaid grade level of 7.4 (range, 4.7 – 9.3. SMOG readability analysis, based on a count of polysyllabic words, consistently rated materials 2 to 3 grade levels higher than did the Flesch-Kincaid analysis. Government sources were significantly lower compared to commercial and industry sources for Flesch-Kincaid grade level and SMOG readability analysis. Content analysis found materials from commercial and industry sources more complex than government-sponsored publications, whereas commercial sources were more thorough in coverage of pediatric oral health topics. Different materials frequently contained conflicting information. Conclusion Pediatric oral health care materials are readily available, yet their quality and readability vary widely. In general, government publications are more readable than their commercial and industry counterparts. The criteria for usability and results of the analyses

  3. Comparison of the toxicity of fluoridation compounds in the nematode Caenorhabditis elegans.

    Science.gov (United States)

    Rice, Julie R; Boyd, Windy A; Chandra, Dave; Smith, Marjolein V; Den Besten, Pamela K; Freedman, Jonathan H

    2014-01-01

    Fluorides are commonly added to drinking water in the United States to decrease the incidence of dental caries. Silicofluorides, such as sodium hexafluorosilicate (Na2 SiF6 ) and fluorosilicic acid (H2 SiF6 ), are mainly used for fluoridation, although fluoride salts such as sodium fluoride (NaF) are also used. Interestingly, only the toxicity of NaF has been examined and not that of the more often used silicofluorides. In the present study, the toxicities of NaF, Na2 SiF6 , and H2 SiF6 were compared. The toxicity of these fluorides on the growth, feeding, and reproduction in the alternative toxicological testing organism Caenorhabditis elegans was examined. Exposure to these compounds produced classic concentration-response toxicity profiles. Although the effects of the fluoride compounds varied among the 3 biological endpoints, no differences were found between the 3 compounds, relative to the fluoride ion concentration, in any of the assays. This suggests that silicofluorides have similar toxicity to NaF. © 2013 SETAC.

  4. Synthesis of Mg2FeH6 containing as additives transition metal and transition metal fluorides or carbon

    International Nuclear Information System (INIS)

    Zepon, G.; Leiva, D.R.; Botta, W.J.

    2010-01-01

    The Mg 2 FeH 6 is a promising way of storing hydrogen in solid form, composed by elements that have low cost and, at the same time, high volumetric storage density: 150 kg H 2 /m 3 . However, this complex hydride is not easily synthesized as a single phase material. The hydrogen sorption high temperature and slow kinetics are the major limitations for the practical application of the Mg 2 FeH 6 as a hydrogen storage material. Little is known about the effects of additives in Mg 2 FeH 6 based nanocomposites in this work were synthesized by MAE under hydrogen atmosphere nanocomposites based on Mg 2 FeH 6 containing additives as transition metals, transition metals fluorides of transition metals or carbon, in order to obtain information on the effects of the selected additives. To this end, we used characterization techniques such as XRD, SEM and TEM, thermal analysis by DSC and curves made in apparatus PCT.(author)

  5. DEGREE OF AWARENESS OF SOFT RELINING MATERIALS BY DENTAL TECHNICIANS

    Directory of Open Access Journals (Sweden)

    Ilian Hristov

    2017-10-01

    Full Text Available The aim of the current investigation is to analyze the dental-technicians’ awareness of the soft relining materials, their characteristics, advantages, shortcomings and methods for relining. Materials and methods: For the purpose of this investigation a standard questionnaire has been presented. A direct survey method, documentary and statistical method, as well as graphical methods, including tables, charts, graphics and figures, were used. Data were analysed with the help of IBM SPSS Statistics (ver. 19. Results: One hundred and eight dental technicians were included in the survey, evenly distributed by gender. Removable and fixed prosthodontics is the most commonly mentioned spheres of dental activities. Almost all included in the investigation point out the laboratory relining method as the most frequently used. Acrylic and silicone SRM are the most used groups of relining materials. Change of colour and hardness are the most frequently noticed shortcomings of these materials. The majority of the dental technicians declare that they have never done replacement of SRM or the relining has lasted more than a year. Discussion: The correlation between the age and the years of labour service among the participants is quite obvious. Most of them start working soon after their graduation. Removable prosthodontics is among the priorities for the majority of the labs. Conclusion: Although their unambiguous advantages, the soft relining materials have lots of shortcomings as well. The major problems are connected with their change of colour and hardness. Nevertheless, the dental technicians find them useful and reliable in overcoming specific prosthetic problems.

  6. Updating Classifications of Ceramic Dental Materials: A Guide to Material Selection.

    Science.gov (United States)

    McLaren, Edward A; Figueira, Johan

    2015-06-01

    The indications for and composition of today's dental ceramic materials serve as the basis for determining the appropriate class of ceramics to use for a given case. By understanding the classifications, composition, and characteristics of the latest all-ceramic materials, which are presented in this article in order of most to least conservative, dentists and laboratory technicians can best determine the ideal material for a particular treatment.

  7. Advances in Dental Materials through Nanotechnology: Facts, Perspectives and Toxicological Aspects.

    Science.gov (United States)

    Padovani, Gislaine C; Feitosa, Victor P; Sauro, Salvatore; Tay, Franklin R; Durán, Gabriela; Paula, Amauri J; Durán, Nelson

    2015-11-01

    Nanotechnology is currently driving the dental materials industry to substantial growth, thus reflecting on improvements in materials available for oral prevention and treatment. The present review discusses new developments in nanotechnology applied to dentistry, focusing on the use of nanomaterials for improving the quality of oral care, the perspectives of research in this arena, and discussions on safety concerns regarding the use of dental nanomaterials. Details are provided on the cutting-edge properties (morphological, antibacterial, mechanical, fluorescence, antitumoral, and remineralization and regeneration potential) of polymeric, metallic and inorganic nano-based materials, as well as their use as nanocluster fillers, in nanocomposites, mouthwashes, medicines, and biomimetic dental materials. Nanotoxicological aspects, clinical applications, and perspectives for these nanomaterials are also discussed. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. Efficacy of fluoride varnish for preventing white spot lesions and gingivitis during orthodontic treatment with fixed appliances-a prospective randomized controlled trial.

    Science.gov (United States)

    Kirschneck, Christian; Christl, Jan-Joachim; Reicheneder, Claudia; Proff, Peter

    2016-12-01

    The development of white spot lesions around orthodontic brackets and gingivitis is a common problem during orthodontic treatment with fixed appliances. This prospective randomized double-blind controlled clinical trial investigated the preventive efficacy of a one-time application of two commonly used fluoride varnishes in patients with low to moderate caries risk. Ninety adolescent orthodontic patients with a low to moderate caries risk were prospectively randomized to three groups of 30 patients each: (1) standardized dental hygiene with fluoride toothpaste and one-time application of placebo varnish (control) or (2) of elmex® fluid or (3) of Fluor Protector S on all dental surfaces at the start of fixed therapy. The extent of enamel demineralization and gingivitis was determined with the ICDAS and the gingivitis index (GI) at baseline and after 4, 12, and 20 weeks. Each treatment group showed a significant increase of the ICDAS index, but not of the GI over the course of time with no significant intergroup differences detectable. A one-time application of fluoride varnish at the start of orthodontic treatment did not provide any additional preventive advantage over sufficient dental hygiene with fluoride toothpaste with regard to formation of white spots and gingivitis in patients with a low to moderate caries risk. In dental practice, patients often receive an application of fluoride varnish at the start of orthodontic treatment with fixed appliances. However, the efficacy of this procedure is still unclear.

  9. The presence of antimony in various dental filling materials

    International Nuclear Information System (INIS)

    Molokhia, Anat; Combe, E.C.; Lilley, J.D.

    1985-01-01

    Antimony was determined in a number of non-metallic dental materials currently used for tooth restoration. The method applied was instrumental neutron activation analysis. The concentration of antimony in some of the brands tested was found to be as high as 900 fold that in the normal hard dental tissues. (author)

  10. Drinking water pollution with respective of fluoride in the semi-arid region of Basara, Nirmal district, Telangana State, India.

    Science.gov (United States)

    Narsimha, Adimalla; Sudarshan, Venkatayogi

    2018-02-01

    Fluoride is an essential microelement for human health. Statistically, smaller quantities (water are usually considered to have a beneficial effect on the rate of occurrence of dental caries, particularly among children, but excessive continuous exposure (>1.5 mg/L) to fluoride can give rise to a number of adverse effects, including dental fluorosis, skeletal fluorosis, increased rate of bone fractures, decreased birth rates, increased rate of urolithiasis (kidney stones), impaired thyroid function, and impaired development of intelligence in children [1], [2], [3], [4], [5]. The data suggested that the north-eastern part of the Basara region having high fluoride concentration, which is unsuitable for drinking purposes. Hence, this unsuitable drinking water cause fluorosis in this Basara and surrounding villages, and especially based on the findings suggests, where the fluoride levels are in below maximum permissible limits that water ingests to the people to avoid further fluorosis.

  11. Fluoride concentration level in rural area in Poldasht city and daily fluoride intake based on drinking water consumption with temperature.

    Science.gov (United States)

    Mohammadi, Ali Akbar; Yousefi, Mahmood; Mahvi, Amir Hossein

    2017-08-01

    Long-term exposure to high level of fluoride can caused several adverse effects on human health including dental and skeletal fluorosis. We investigated all the drinking water source located in rural areas of Poldasht city, west Azerbaijan Province, North West Iran between 2014 and 2015. Fluoride concentration of water samples was measured by SPADNS method. We found that in the villages of Poldasht the average of fluoride concentration in drinking water sources (well, and the river) was in the range mg/l 0.28-10.23. The average daily received per 2 l of drinking water is in the range mg/l 0.7-16.6 per day per person. Drinking water demands cause fluorosis in the villages around the area residents and based on the findings of this study writers are announced suggestions below in order to take care of the health of area residents.

  12. Dental caries

    DEFF Research Database (Denmark)

    Pitts, Nigel B; Zero, Domenick T; Marsh, Phil D

    2017-01-01

    Dental caries is a biofilm-mediated, sugar-driven, multifactorial, dynamic disease that results in the phasic demineralization and remineralization of dental hard tissues. Caries can occur throughout life, both in primary and permanent dentitions, and can damage the tooth crown and, in later life......, exposed root surfaces. The balance between pathological and protective factors influences the initiation and progression of caries. This interplay between factors underpins the classification of individuals and groups into caries risk categories, allowing an increasingly tailored approach to care. Dental...... caries is an unevenly distributed, preventable disease with considerable economic and quality-of-life burdens. The daily use of fluoride toothpaste is seen as the main reason for the overall decline of caries worldwide over recent decades. This Primer aims to provide a global overview of caries...

  13. Protocol for Northern Ireland Caries Prevention in Practice Trial (NIC-PIP) trial: a randomised controlled trial to measure the effects and costs of a dental caries prevention regime for young children attending primary care dental services.

    Science.gov (United States)

    Tickle, Martin; Milsom, Keith M; Donaldson, Michael; Killough, Seamus; O'Neill, Ciaran; Crealey, Grainne; Sutton, Matthew; Noble, Solveig; Greer, Margaret; Worthington, Helen V

    2011-10-10

    Dental caries is a persistent public health problem with little change in the prevalence in young children over the last 20 years. Once a child contracts the disease it has a significant impact on their quality of life. There is good evidence from Cochrane reviews including trials that fluoride varnish and regular use of fluoride toothpaste can prevent caries. The Northern Ireland Caries Prevention in Practice Trial (NIC-PIP) trial will compare the costs and effects of a caries preventive package (fluoride varnish, toothpaste, toothbrush and standardised dental health education) with dental health education alone in young children. A randomised controlled trial on children initially aged 2 and 3 years old who are regular attenders at the primary dental care services in Northern Ireland. Children will be recruited and randomised in dental practices. Children will be randomised to the prevention package of both fluoride varnish (twice per year for three years), fluoride toothpaste (1,450 ppm F) (supplied twice per year), a toothbrush (supplied twice a year) or not; both test and control groups receive standardised dental health education delivered by the dentist twice per year. Randomisation will be conducted by the Belfast Trust Clinical Research Support Centre ([CRSC] a Clinical Trials Unit). 1200 participants will be recruited from approximately 40 dental practices. Children will be examined for caries by independent dental examiners at baseline and will be excluded if they have caries. The independent dental examiners will examine the children again at 3 years blinded to study group.The primary end-point is whether the child develops caries (cavitation into dentine) or not over the three years. One secondary outcome is the number of carious surfaces in the primary dentition in children who experience caries. Other secondary outcomes are episodes of pain, extraction of primary teeth, other adverse events and costs which will be obtained from parental

  14. Caries dental en escolares del Distrito Federal Dental caries in school children in Mexico City

    Directory of Open Access Journals (Sweden)

    MARÍA ESTHER IRIGOYEN-CAMACHO

    1997-03-01

    Full Text Available Objetivo. Presentar las estimaciones de la prevalencia y la severidad de caries dental, así como las necesidades de tratamiento de la población escolar del Distrito Federal examinada en la encuesta de caries dental que se llevó a cabo en 1988 con la finalidad de obtener datos basales sobre caries en los escolares al inicio del Programa Nacional de Fluoruración de la Sal en México. Material y métodos. La población de estudio fue seleccionada empleando un marco muestral basado en el listado de las escuelas primarias y los jardines de niños registrados por la Secretaría de Educación Pública en 1988. En el examen de la cavidad bucal de los escolares se utilizaron los criterios diagnósticos señalados por la Organización Mundial de la Salud. Resultados. Un total de 4 475 escolares de 5 a 12 años de edad participaron en el estudio. La prevalencia de caries dental en la población alcanzó 90.5%. El índice de necesidades de tratamiento fue elevado (79.6%. El promedio de los índices de caries en los escolares de 12 años de edad fue CPOD= 4.42 (desviación estándar –DE– 3.2 y CPOS= 6.53 (DE 4.8. Conclusiones. Los resultados de la encuesta subrayan la pertinencia de un programa preventivo de amplia cobertura, como el de fluoruración de la sal. Además, muestran que se requiere elaborar estrategias para mejorar el acceso de la población escolar a los servicios odontológicos del sistema de salud en México.Objective. To estimate the prevalence and severity of dental caries and the dental treatment necessities of school children in Mexico City. The studied population was surveyed for dental caries in 1988 to obtain data necessary for the National Program of Salt Fluoridation in Mexico. Material and methods. The population was selected with a sample frame based on a list of Kindergardens and primary schools registered at the Ministry of Public Education in 1988. The oral cavity examination was based on diagnostic criteria marked by the

  15. Comparing the Air Abrasion Cutting Efficacy of Dentine Using a Fluoride-Containing Bioactive Glass versus an Alumina Abrasive: An In Vitro Study

    Directory of Open Access Journals (Sweden)

    Melissa H. X. Tan

    2015-01-01

    Full Text Available Air abrasion as a caries removal technique is less aggressive than conventional techniques and is compatible for use with adhesive restorative materials. Alumina, while being currently the most common abrasive used for cutting, has controversial health and safety issues and no remineralisation properties. The alternative, a bioactive glass, 45S5, has the advantage of promoting hard tissue remineralisation. However, 45S5 is slow as a cutting abrasive and lacks fluoride in its formulation. The aim of this study was to compare the cutting efficacy of dentine using a customised fluoride-containing bioactive glass Na0SR (38–80 μm versus the conventional alumina abrasive (29 μm in an air abrasion set-up. Fluoride was incorporated into Na0SR to enhance its remineralisation properties while strontium was included to increase its radiopacity. Powder outflow rate was recorded prior to the cutting tests. Principal air abrasion cutting tests were carried out on pristine ivory dentine. The abrasion depths were quantified and compared using X-ray microtomography. Na0SR was found to create deeper cavities than alumina (p<0.05 despite its lower powder outflow rate and predictably reduced hardness. The sharper edges of the Na0SR glass particles might improve the cutting efficiency. In conclusion, Na0SR was more efficacious than alumina for air abrasion cutting of dentine.

  16. Urinary fluoride output in children following the use of a dual-fluoride varnish formulation

    Directory of Open Access Journals (Sweden)

    Kelly Polido Kaneshiro Olympio

    2009-06-01

    Full Text Available OBJECTIVE: This study evaluated the bioavailability of fluoride after topical application of a dual-fluoride varnish commercially available in Brazil, when compared to DuraphatTM. MATERIAL AND METHODS: The urinary fluoride output was evaluated in seven 5-year-old children after application of the fluoride varnishes, in two different phases. In the first phase (I, children received topical application of the fluoride varnish Duofluorid XII (2.92% fluorine, calcium fluoride + 2.71% fluorine, sodium fluoride, FGM TM. After 1-month interval (phase II, the same amount (0.2 mL of the fluoride varnish Duraphat (2.26% fluorine, sodium fluoride, ColgateTM was applied. Before each application all the volunteers brushed their teeth with placebo dentifrice for 7 days. Urinary collections were carried out 24 h prior up to 48 h after the applications. Fluoride intake from the diet was also estimated. Fluoride concentration in diet samples and urine was analyzed with the fluoride ion-specific electrode and a miniature calomel reference electrode coupled to a potentiometer. Data were tested by ANOVA and Tukey's post hoc test (p<0.05. RESULTS: There were significant differences in the urinary fluoride output between phases I and II. The use of Duofluorid XII did not significantly increase the urinary fluoride output, when compared to baseline levels. The application of Duraphat caused a transitory increase in the urinary fluoride output, returning to baseline levels 48 h after its use. CONCLUSIONS: The tested varnish formulation, which has been shown to be effective in in vitro studies, also can be considered safe.

  17. Drinking Water Fluoride Levels for a City in Northern Mexico (Durango Determined Using a Direct Electrochemical Method and Their Potential Effects on Oral Health

    Directory of Open Access Journals (Sweden)

    Nelly Molina Frechero

    2013-01-01

    Full Text Available Fluoride is ingested primarily through consuming drinking water. When drinking water contains fluoride concentrations >0.7 parts per million (ppm, consuming such water can be toxic to the human body; this toxicity is called “fluorosis.” Therefore, it is critical to determine the fluoride concentrations in drinking water. The objective of this study was to determine the fluoride concentration in the drinking water of the city of Durango. The wells that supply the drinking water distribution system for the city of Durango were studied. One hundred eighty-nine (189 water samples were analyzed, and the fluoride concentration in each sample was quantified as established by the law NMX-AA-077-SCFI-2001. The fluoride concentrations in such samples varied between 2.22 and 7.23 ppm with a 4.313 ± 1.318 ppm mean concentration. The highest values were observed in the northern area of the city, with a 5.001 ± 2.669 ppm mean value. The samples produced values that exceeded the national standard for fluoride in drinking water. Chronic exposure to fluoride at such concentrations produces harmful health effects, the first sign of which is dental fluorosis. Therefore, it is essential that the government authorities implement water defluoridation programs and take preventative measures to reduce the ingestion of this toxic halogen.

  18. Drinking Water Fluoride Levels for a City in Northern Mexico (Durango) Determined Using a Direct Electrochemical Method and Their Potential Effects on Oral Health

    Science.gov (United States)

    Molina Frechero, Nelly; Sánchez Pérez, Leonor; Castañeda Castaneira, Enrique; Oropeza Oropeza, Anastasio; Gaona, Enrique; Salas Pacheco, José; Bologna Molina, Ronell

    2013-01-01

    Fluoride is ingested primarily through consuming drinking water. When drinking water contains fluoride concentrations >0.7 parts per million (ppm), consuming such water can be toxic to the human body; this toxicity is called “fluorosis.” Therefore, it is critical to determine the fluoride concentrations in drinking water. The objective of this study was to determine the fluoride concentration in the drinking water of the city of Durango. The wells that supply the drinking water distribution system for the city of Durango were studied. One hundred eighty-nine (189) water samples were analyzed, and the fluoride concentration in each sample was quantified as established by the law NMX-AA-077-SCFI-2001. The fluoride concentrations in such samples varied between 2.22 and 7.23 ppm with a 4.313 ± 1.318 ppm mean concentration. The highest values were observed in the northern area of the city, with a 5.001 ± 2.669 ppm mean value. The samples produced values that exceeded the national standard for fluoride in drinking water. Chronic exposure to fluoride at such concentrations produces harmful health effects, the first sign of which is dental fluorosis. Therefore, it is essential that the government authorities implement water defluoridation programs and take preventative measures to reduce the ingestion of this toxic halogen. PMID:24348140

  19. Drinking water fluoride levels for a city in northern Mexico (durango) determined using a direct electrochemical method and their potential effects on oral health.

    Science.gov (United States)

    Molina Frechero, Nelly; Sánchez Pérez, Leonor; Castañeda Castaneira, Enrique; Oropeza Oropeza, Anastasio; Gaona, Enrique; Salas Pacheco, José; Bologna Molina, Ronell

    2013-01-01

    Fluoride is ingested primarily through consuming drinking water. When drinking water contains fluoride concentrations>0.7 parts per million (ppm), consuming such water can be toxic to the human body; this toxicity is called "fluorosis." Therefore, it is critical to determine the fluoride concentrations in drinking water. The objective of this study was to determine the fluoride concentration in the drinking water of the city of Durango. The wells that supply the drinking water distribution system for the city of Durango were studied. One hundred eighty-nine (189) water samples were analyzed, and the fluoride concentration in each sample was quantified as established by the law NMX-AA-077-SCFI-2001. The fluoride concentrations in such samples varied between 2.22 and 7.23 ppm with a 4.313±1.318 ppm mean concentration. The highest values were observed in the northern area of the city, with a 5.001±2.669 ppm mean value. The samples produced values that exceeded the national standard for fluoride in drinking water. Chronic exposure to fluoride at such concentrations produces harmful health effects, the first sign of which is dental fluorosis. Therefore, it is essential that the government authorities implement water defluoridation programs and take preventative measures to reduce the ingestion of this toxic halogen.

  20. Role of polyphenols and nonpolyphenols against toxicity induced by fluoride: a comprehensive review.

    Science.gov (United States)

    Claudio, Samuel R; Handan, Bianca A; Gomes de Moura, Carolina F; Viana, Milena de Barros; Yamauchi, Liria Y; Aguiar, Odair; Oshima, Celina T F; Ribeiro, Daniel A

    2018-04-17

    Since its discovery as an antimicrobial agent, fluoride has been used in the control of dental caries. Many studies have shown that the chronic exposure of fluoride in high concentrations causes adverse effects in multiple organs; the use of bioactive compounds present in foods as a tool to mitigate the effects of fluoride could potentially be useful for populations in different parts of the world are exposed to fluoride in a chronic and systemic way. Thus, the aim of this comprehensive review is to present and discuss the published papers that focused on the use of polyphenols and nonpolyphenols that can mitigate the harmful activities promoted by fluoride exposure. Certainly, these data will contribute toward a better understanding of the role of food compounds in the pathological outcomes induced by fluoride. The new information will be added to that already available for regulatory purposes as a safe way to promote oral healthcare and prevent oral carcinogenesis.

  1. Purification of Drinking Water from Fluorides by Reverse Osmosis

    Directory of Open Access Journals (Sweden)

    Aleksander A.

    2018-03-01

    Full Text Available Introduction: An important task in the sphere of sanitary and epidemiological welfare of the population of the Russian Federation is provision of drinking water. Tap water must not contain pathogenic bacteria and dangerous chemicals. Purification systems regulate the concentration of fluoride ions in drinking water. The aim of this paper is to study the possibility of purifying tap water from fluoride ions by reverse osmosis. Materials and Methods: We used the Alfa Laval PilotUnit 2.5 "RO/NF with a set of spiral-type membrane elements RO99-2517/48 to remove fluoride ions. We measured the concentration of fluoride ions by the potentiometric method using the Hanna HI 2211 (pH/mV/T. Fluoride-selective electrode ELIS 131 F was used as an indicator electrode and the standard chloride-silver electrode EVL-1M3 was used as a reference electrode. Both the calibration and buffer solutions were prepared from chemically pure reagents and A. R. purity for analysis reagents according to GOST 4386-89. Results: A single passage of water through the reverse osmosis membrane reduced the concentration of fluoride ions from 2.29 ± 0.02 to 0.240 ± 0.015 mg/l. Double passage of water reduced the concentration by a factor of two. As the concentration of fluoride ions increased in the retentate, the concentration in the filtrate slightly increased too. Purification of water reduced the concentration of fluoride ions from 20 mg/l, to 0.5 mg/l. Discussion and Conclusions: Thus, using the Alfa Laval PilotUnit 2.5" RO/NF with a set of spiral-type membrane elements RO99-2517/48 filters tap water of ions of fluoride to the maximum allowable concentration. This study opens the perspective of using reverse osmosis to purify tap water with high concentration of fluoride ions.

  2. Fluoride Exposure in Early Life as the Possible Root Cause of Disease In Later Life.

    Science.gov (United States)

    Nakamoto, Tetsuo; Rawls, H Ralph

    2018-05-15

    Fluoride, one of the most celebrated ingredients for the prevention of dental caries in the 20th century, has also been controversial for its use in dentifrices and other applications. In the current review, we have concentrated primarily on early-life exposure to fluoride and how it may affect the various organs. The most recent controversial aspects of fluoride are related to toxicity of the developing brain and how it may possibly result in the decrease of intelligence quotient (IQ), autism, and calcification of the pineal gland. In addition, it has been reported to have possible effects on bone and thyroid glands. If nutritional stress is applied during a critical period of growth and development, the organ(s) and/or body will never recover once they pass through the critical period. For example, if animals are force-fed during experiments, they will simply get fat but never reach the normal size. Although early-life fluoride exposure causing fluorosis is well reported in the literature, the dental profession considers it primarily as an esthetic rather than a serious systemic problem. In the current review, we wanted to raise the possibility of future disease as a result of early-life exposure to fluoride. It is not currently known how fluoride will become a cause of future disease. Studies of other nutritional factors have shown that the effects of early nutritional stress are a cause of disease in later life.

  3. Effects of Topical Fluoride on the Marginal Microleakage of Composite Resin and Resin-Modified Glass Ionomer Restorations in Primary Molars: An In-vitro Study

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    Fatemeh Mir

    2017-12-01

    Full Text Available Introduction: Topical fluoride may deteriorate dental restorations. The present study aimed to evaluate the effects of topical fluoride on the marginal microleakage of composite resin and resin-modified glass ionomer (RMGI restorations in primary molars. Materials and Methods: In this experimental study, 60 primary molars were randomly divided into six groups of 10 based on the type of the restoration materials and before/after the application of fluoride gel, including FC (fluoride + composite, CF (composite + fluoride, C (composite, FG (fluoride + RMGI, GF (RMGI + fluoride, and G (RMGI. Class V cavities were prepared on the buccal surface, so that the gingival margins were located in cementum. After storing, thermocycling, and immersing the specimens in basic fuchsin, they were sectioned buccolingually and evaluated in terms of dye penetration. Data analysis was performed in SPSS version 18 using Kruskal-Wallis and Mann-Whitney U test at the significance level of 0.05. Results: No significant difference was observed between the three composite groups in terms of microleakage (P>0.05. In the RMGI groups, GF showed a significantly higher microleakage compared to G (P=0.029. However, no significant difference was observed between the other groups in this regard (P>0.05. Moreover, comparison of composite and RMGI groups (matched in terms of fluoride application indicated that microleakage was significantly higher in FG than FC (P=0.024, as well as in GF than CF (P=0.002. However, no significant difference was observed between groups C and G in this regard (P=0.268. Conclusion: According to the results, the marginal seal of composite restorations in the primary molars were not affected by the acidic fluoride gel. On the other hand, applying the acidic fluoride gel was associated with a higher microleakage in the cavities restored with RMGI.

  4. Does lower lifetime fluoridation exposure explain why people outside capital cities have poor clinical oral health?

    Science.gov (United States)

    Crocombe, L A; Brennan, D S; Slade, G D

    2015-03-26

    Australians outside state capital cities have greater caries experience than their counterparts in capital cities. We hypothesized that differing water fluoridation exposures was associated with this disparity. Data were the 2004-06 Australian National Survey of Adult Oral Health. Examiners measured participant decayed, missing and filled teeth and DMFT Index and lifetime fluoridation exposure was quantified. Multivariable linear regression models estimated differences in caries experience between capital city residents and others, with and without adjustment for fluoridation exposure. There was greater mean lifetime fluoridation exposure in state capital cities (59.1%, 95% confidence interval=56.9,61.4) than outside capital cities (42.3, confidence interval=36.9,47.6). People located outside capital city areas had differing socio-demographic characteristics and dental visiting patterns, and a higher mean DMFT (Capital cities=12.9, Non-capital cities=14.3, p=0.02), than people from capital cities. After adjustment for socio-demographic characteristics and dental visits, DMFT of people living in capital cities was less than non-capital city residents (Regression coefficient=0.8, p=0.01). The disparity was no longer statistically significant (Regression coefficient=0.6, p=0.09) after additional adjustment for fluoridation exposure. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  5. Calculated energy response of lithium fluoride finger-tip dosimeters

    International Nuclear Information System (INIS)

    Johns, T.F.

    1965-07-01

    Calculations have been made of the energy response of the lithium fluoride thermoluminescent dosimeters being used at A.E.E. Winfrith for the measurement of radiation doses to the finger-tips of people handling radio-active materials. It is shown that the energy response is likely to be materially affected if the sachet in which the powder is held contains elements with atomic numbers much higher than 9 (e.g. if the sachet is made from polyvinyl chloride). (author)

  6. Dental Chairside Technique. Student's Manual.

    Science.gov (United States)

    Apfel, Maura; Weaver, Trudy Karlene

    This manual is part of a series dealing with skills and information needed by students in dental assisting. The individualized student materials are suitable for classroom, laboratory, or cooperative training programs. This student manual contains four units covering the following topics: local anesthesia; dental office emergencies; oral hygiene;…

  7. The use of selective electrodes for the control of nuclear materials

    International Nuclear Information System (INIS)

    Pires, M.A.F.; Abrao, A.

    1984-01-01

    The use of ion selective electrodes is discussed for the determination of nitrate, chloride and fluoride in several materials used in the fuel cycle. The determination of nitrate and chloride in thorium compounds, the analysis of fluoride and chloride in uranium compounds and the determination of fluoride in crude phosphoric acid are described. The control of fluoride in urine of individuals that handle materials containing fluor and its compounds is also described. (C.L.B.) [pt

  8. Theobromine Effects on Enamel Surface Microhardness: In Vitro

    OpenAIRE

    Grace Syafira; Rina Permatasari; Nina Wardani

    2013-01-01

    Dental caries is still a dental health problem in Indonesia. Fluoride, one of the dental caries prevention material, but its safety and the danger of fluorosis is still debated. Theobromine is an alkaloid compound contained in cocoa beans. Theobromine is believed to increase enamel microhardness with mineral changes in the enamel superficial layer. Objectives: To determine the influence of theobromine on the enamel surface microhardness. Methods: This study used 40 premolar tooth crown pieces...

  9. Utilization of Dental Services in Public Health Center: Dental Attendance, Awareness and Felt Needs.

    Science.gov (United States)

    Pewa, Preksha; Garla, Bharath K; Dagli, Rushabh; Bhateja, Geetika Arora; Solanki, Jitendra

    2015-10-01

    In rural India, dental diseases occur due to many factors, which includes inadequate or improper use of fluoride and a lack of knowledge regarding oral health and oral hygiene, which prevent proper screening and dental care of oral diseases. The objective of the study was to evaluate the dental attendance, awareness and utilization of dental services in public health center. A cross-sectional study was conducted among 251 study subjects who were visiting dental outpatient department (OPD) of public health centre (PHC), Guda Bishnoi, and Jodhpur using a pretested proforma from month of July 2014 to October 2014. A pretested questionnaire was used to collect the data regarding socioeconomic status and demographic factors affecting the utilization of dental services. Pearson's Chi-square test and step-wise logistic regression were applied for the analysis. Statistically significant results were found in relation to age, educational status, socioeconomic status and gender with dental attendance, dental awareness and felt needs. p-value dental services, thereby increasing the oral health status of the population.

  10. [Study on the relationship between ER Rsa I gene polymorphism and children's dental fluorosis].

    Science.gov (United States)

    Ba, Yue; Li, Hai-Xia; Yin, Gong-Ju; Wu, Wei-Hua; Yu, Bo; Cheng, Xue-Min; Cui, Liu-Xin

    2009-09-01

    To explore the distribution of ER Rsa I genotype in children who lived in the areas with or without high fluoride, and evaluate the relationship between ER Rsa I gene polymorphism and children's dental fluorosis. Children aged 8 to 12 years, born and raised in high fluoride areas and control areas in two counties of Henan Province were recruited. The Rsa I marker of ER gene was genotyped in 237 children composed of both dental fluorosis cases and controls by PCR-RFLP procedure. Urine fluoride was detected with fluoride ion selective electrode method. The frequency distribution of ER Rsa I genotype was rr 60.81% (45/74), Rr 27.02% (20/74), RR 12.16% (9/74) in children with fluorosis; rr 73.91% (51/69), Rr 20.29% (14/69), RR 5.80% (4/69) in children without fluorosis from high fluoride areas, and rr 63.83% (60/94), Rr 34.04% (32/94), RR 2.13% (2/94) in the children without fluorosis from control areas respectively. There were no significant differences in the three groups (P>0.05), but children carrying allele R of ER Rsa I had a significantly increased risk of dental fluorosis (OR=1.821, 95% CI: 1.013-3.274) compared to children carrying the allele r in endemic fluorosis areas. Although no significant difference was found in ER Rsa I genotype between cases and non-dental fluorosis in endemic fluorosis areas, children carrying R allele of ER Rsa I had a higher risk compared to children carrying r allele, and the further study is needed.

  11. Fluoride ions sorption of the water using natural and modified hematite with aluminium hydroxide

    International Nuclear Information System (INIS)

    Teutli S, E. A.

    2011-01-01

    Fluorine is a mineral known for its dental benefits, but fluoride ions can cause fluoro sis in excessive quantities. There are many epidemiological studies on possible adverse effects resulting from prolonged ingestion of fluoride through drinking water. These studies demonstrate that fluoride mainly affects the bone tissue (bones and teeth), may produce an adverse effect on tooth enamel and can cause mild dental fluoro sis at concentrations from 0.9 to 1.2 mg/L in drinking water. In several states of Mexico, water contaminated with fluoride ions can be found, such as Aguascalientes, Chihuahua, Coahuila, Durango, Guanajuato, Sonora, Zacatecas, San Luis Potosi and Jalisco, where the fluoride ions levels are higher than 1.5 mg/L, established by the Mexican Official Standard (NOM-127-Ssa-2000) which sets the permissible limits of water for human use and consumption. Currently, several technologies have been proposed to remove fluoride ions from water such as precipitation methods which are based on the addition of chemicals to water and sorption methods to removed fluoride ions by sorption or ion exchange reactions by some suitable substrate capable of regenerate and reuse. In this work, the sorption of fluoride ions using unmodified and modified hematite with aluminum hydroxide to remove fluoride ions from water by bath experiments was studied. The hematite was modified by treating it with aluminum hydroxide, NaOH and Al 2 (SO 4 ) 3 solutions. The characterization of hematite before and after modification with aluminum hydroxide was studied by X-ray diffraction, scanning electron microscopy, EDS and Bet. The effect of ph, contact time, concentration of fluoride ions, and the dose of sorbent on the sorption of fluoride ions by the modified hematite were studied. Equilibrium was reached within 48 hours of contact time and the maximum sorption of fluoride ions were in the range pH eq between 2.3 and 6.2. Sorption capacities of fluoride ions as a function of dose of

  12. Radiolytic Effects on Fluoride Impurities in a U3O8 Matrix

    International Nuclear Information System (INIS)

    Icenhour, A.S.

    2000-01-01

    The safe handling and storage of radioactive materials require an understanding of the effects of radiolysis on those materials. Radiolysis may result in the production of gases (e.g., corrosives) or pressures that are deleterious to storage containers. A study has been performed to address these concerns as they relate to the radiolysis of residual fluoride compounds in uranium oxides

  13. Titanium Nitride and Nitrogen Ion Implanted Coated Dental Materials

    Directory of Open Access Journals (Sweden)

    David W. Berzins

    2012-07-01

    Full Text Available Titanium nitride and/or nitrogen ion implanted coated dental materials have been investigated since the mid-1980s and considered in various applications in dentistry such as implants, abutments, orthodontic wires, endodontic files, periodontal/oral hygiene instruments, and casting alloys for fixed restorations. Multiple methodologies have been employed to create the coatings, but detailed structural analysis of the coatings is generally lacking in the dental literature. Depending on application, the purpose of the coating is to provide increased surface hardness, abrasion/wear resistance, esthetics, and corrosion resistance, lower friction, as well as greater beneficial interaction with adjacent biological and material substrates. While many studies have reported on the achievement of these properties, a consensus is not always clear. Additionally, few studies have been conducted to assess the efficacy of the coatings in a clinical setting. Overall, titanium nitride and/or nitrogen ion implanted coated dental materials potentially offer advantages over uncoated counterparts, but more investigation is needed to document the structure of the coatings and their clinical effectiveness.

  14. Effect of oral health education and fluoridated dentifrices on the oral health status of visually impaired children

    Directory of Open Access Journals (Sweden)

    Sujay Kumar

    2012-01-01

    Full Text Available Visually impaired children are challenged everyday in their everyday skills. Oral hygiene practices among visually impaired children require a special approach with time and patience. The purpose of this study was to evaluate the effect of oral health education and fluoridated dentifrices on the oral health status of visually impaired children. Materials and Methods: Fifty visually impaired children between 8 and 12 years of age formed the study group. Oral health education and motivation was done with the help of Braille. Modified Bass method of brushing was taught to the children and the required dental treatment was done. Subjects were randomly divided into two equal groups fluoridated and non-fluoridated. Oral hygiene index -simplified, DMFT, deft index, and Streptococcus mutans and Lactobacillus count were assessed at baseline, immediately after the treatment and at 3, 6, and 12 month intervals. The oral health awareness was assessed using a questionnaire at the beginning and end of the study. Results: At baseline, the mean OHI-S, DMFT and deft scores were 2.72, 0.47, and 0.51 respectively. At the end of 12 months there was a significant decrease in OHI-S scores in the fluoridated group. No significant difference was seen in DMFT and deft between the fluoridated and non-fluoridated groups at the different time interval. After the oral health education and comprehensive treatment there was a reduction in Streptococcus mutans and Lactobacillus counts in both groups; however, at the end of 3, 6, 12 months there was a significant decrease in fluoridated group as compared to the non-fluoridated. The oral health awareness increased significantly at the end of the study. Conclusion: The oral health education and motivation formulated for the visually impaired children was effective in improving their oral health status. Fluoridated dentifrices decreased the Streptococcus mutans and Lactobacillus counts and improved the oral hygiene status.

  15. The effects of fluoride concentration and the level of cariogenic challenge on caries development in desalivated rats.

    Science.gov (United States)

    Tabchoury, C M; Holt, T; Pearson, S K; Bowen, W H

    1998-12-01

    Dental caries is an infectious and transmissible disease that continues to affect the majority of people. The presence of carbohydrate, mainly sucrose in the diet, is an important factor in its occurrence. The amount of fluoride required for optimal protective effect where there is a high caries challenge is unclear. Differences in the intensity of cariogenic challenge, for whatever reason, may play a part in determining fluctuations in the effectiveness of fluoride. The purpose of this study was to evaluate the effect of different concentrations of fluoride on the development of caries and explore the cariostatic effect of fluoride under various levels of cariogenic challenge. The study comprises two experiments. In experiment I, 60 desalivated Sprague Dawley rats infected with Streptococcus sobrinus were offered the following to drink for 21 days: group (1), sterile distilled water (SDW); (2) 10 parts/10(6) F SDW; (3) 20 parts/10(6) F SDW; (4) 30 parts/10(6) F SDW; (5) 40 parts/10(6) F SDW. In experiment II, eight groups of 9 rats were placed in a König Höfer programmed feeder and were exposed to different levels of cariogenic challenge through varying frequency of eating and offered water containing 10 parts/10(6) F. In experiment I, exposure to 20, 30 and 40 parts/10(6) F reduced caries development significantly: fluoride, at 10 parts/10(6), reduced the severity of the carious lesions. In this model of severe cariogenic challenge, the results suggest that elevated concentrations of fluoride might be effective in patients at high caries risk. In experiment II, fluoride reduced the incidence and severity of smooth-surface caries in all groups. The protective effect of fluoride decreased as the number of exposures to sugar increased. It is concluded that the effectiveness of fluoride is influenced by the level of cariogenic challenge and that consideration should be given to adjusting the level of fluoride exposure based on perceived caries risk, and that there

  16. Effect of 10% Strontium Chloride and 5% Potassium Nitrate with Fluoride on Bleached Bovine Enamel.

    Science.gov (United States)

    Alencar, Cristiane de Melo; Pedrinha, Victor Feliz; Araújo, Jesuína Lamartine Nogueira; Esteves, Renata Antunes; Silva da Silveira, Ana Daniela; Silva, Cecy Martins

    2017-01-01

    Dental whitening has been increasingly sought out to improve dental aesthetics, but may cause chemical and morphological changes in dental enamel surfaces. This study evaluated in vitro the effect of 10% strontium chloride and 5% potassium nitrate with fluoride on bovine enamel, through tristimulus colorimetry, Knoop microhardness (KHN), and roughness after bleaching with 35% hydrogen peroxide (HP). The specimens were divided into three groups (n=15): GControl received bleaching treatment with 35% HP; GNitrate received bleaching with 35% HP followed by the application of 5% potassium nitrate with 2% sodium fluoride; and GStrontium received bleaching with 35% HP followed by the application of 10% strontium chloride on the enamel. Next, five specimens of each experimental group were subjected to KHN and tristimulus colorimetry tests, and 10 specimens were subjected to surface roughness (SR) tests. The values obtained for the different groups were compared through analysis of variance (ANOVA) followed by a post-hoc Tukey-Kramer test in addition to Student's T-test for paired data. In the intergroup comparison, KHN final differed statistically ( p 0.05). 10% strontium chloride and 5% potassium nitrate combined with 2% fluoride downplayed morphological changes to the enamel, without interfering with the effectiveness of the bleaching process.

  17. Artifacts by dental materials on magnetic resonance imaging

    International Nuclear Information System (INIS)

    Hong, Hyun Sook; Choi, Deuk Lin; Kim, Ki Jung; Suh, Won Hyuck

    1992-01-01

    Magnetic resonance imaging (MRI) has proved to be a valuable method for evaluation of the head and neck. Unfortunately, metallic devices associated with certain dental fillings and appliances often cause variable artifacts that can obscure normal or pathologic conditions on MR and computed tomography. In this work, we assessed the MR appearance of dental prosthetic materials in vitro and in vivo including precious alloys, nonprecions alloys, resin, amalgam and titanium alloy. For in vivo studies, these materials were placed in healthy volunteer's mouths and then images were assessed. Analysis of the appearance of shape and extent of artifact, and observed influence of these artifacts on the image interpretation at 0.2 Tesla permanent type MR scanner were valuated. Material used as temporary or permanent filling of crowns such as amalgam, precious alloy and, microfilled resin did not cause artifact on the image. The size of the artifact produced by the nonprecious alloys was influenced by the ferromagnetism of the object and the volume prosthesis, and was related to the scanning sequence. Nonprecious alloys produced minimal local signal distortion, where precious alloys, and dental resin had no effect on the MR images in vivo. These results were mainly from a low field strength MR scanner used in this study

  18. Surface properties of anatase TiO2 nanowire films grown from a fluoride-containing solution.

    Science.gov (United States)

    Berger, Thomas; Anta, Juan A; Morales-Flórez, Víctor

    2013-06-03

    Controlling the surface chemistry of nucleating seeds during wet-chemical synthesis allows for the preparation of morphologically well-defined nanostructures. Synthesis conditions play a key role in the surface properties, which directly affect the functional properties of the material. Therefore, it is important to establish post-synthesis treatments to facilitate the optimization of surface properties with respect to a specific application, without losing the morphological peculiarity of the nanostructure. We studied the surface properties of highly crystalline and porous anatase TiO2 nanowire (NW) electrodes, grown by chemical-bath deposition in fluoride-containing solutions, using a combined electrochemical and spectroscopic approach. As-deposited films showed low capacity for catechol adsorption and a poor photoelectrocatalytic activity for water oxidation. Mild thermal annealing at 200 °C resulted in a significant improvement of the electrode photoelectrocatalytic activity, whereas the bulk properties of the NWs (crystal structure, band-gap energy) remained unchanged. Enhancement of the functional properties of the material is discussed on the basis of adsorption capacity and electronic properties. The temperature-induced decrease of recombination centers, along with the concomitant increase of adsorption and reaction sites upon thermal annealing are called to be responsible for such improved performance. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. SU-E-T-89: Characterization of Dental Restoration Material for Cs-137 Radiation Dosimetry.

    Science.gov (United States)

    Ratliff, S; Gustafson, B; Barry, K

    2012-06-01

    The purpose of this work is to characterize the radiation-induced thermoluminescence properties of a dental restoration material and to see if the material might be feasible for use in retrospective radiation dosimetry. Retrospective, or accidental, dosimetry is the study of using nearby materials to measure radiation received by individuals. In this project we obtained samples of Ivoclar Vivadent e.max CAD material, a glass-ceramic used for making dental restorations such as full or partial crowns. The samples were machined into square chips .32 cm × .32 cm × .089 cm and annealed in the same furnace used by the dentist. The samples were exposed to a Cs-137 source using a PMMA source holder and then read in a Harshaw 3500 TLD reader. The samples were read without nitrogen gas flux using heating rates of 5 degrees C/s or 10 degrees C/s up to a maximum temperature of 400 degrees Celsius. The glow curves were analyzed using Systat PeakFIT peak-fitting software and Microsoft Excel spreadsheets. The authors gratefully thank Dr. Aaron Imdieke and the staff of River City Dental, St. Cloud, MN for the dental restoration materials and the use of their dental furnace. A sample subjected to a radiation exposure of .04 C/kg exhibits a glow curve with a prominent peak at approximately 140 degrees Celsius, which is well-modeled by the first order glow curve deconvolution formula developed by Kitis, Gomez-Ros, and Tuyn. The activation energy corresponding to this peak is approximately 1 eV. The thermoluminescent signal fades with time after exposure. Ivoclar Vivadent e.max CAD dental restoration material has the potential to be used as a material for retrospective Cs-137 radiation dosimetry. Future work could look at its thermoluminescent dosimetry properties in more detail and also at other dental restoration materials. The authors would like to thank Dr. Aaron Imdieke and the staff of River City Dental, St. Cloud, MN, for the donation of scrap dental restoration materials and

  20. Synthetic Light-Curable Polymeric Materials Provide a Supportive Niche for Dental Pulp Stem Cells.

    Science.gov (United States)

    Vining, Kyle H; Scherba, Jacob C; Bever, Alaina M; Alexander, Morgan R; Celiz, Adam D; Mooney, David J

    2018-01-01

    Dental disease annually affects billions of patients, and while regenerative dentistry aims to heal dental tissue after injury, existing polymeric restorative materials, or fillings, do not directly participate in the healing process in a bioinstructive manner. There is a need for restorative materials that can support native functions of dental pulp stem cells (DPSCs), which are capable of regenerating dentin. A polymer microarray formed from commercially available monomers to rapidly identify materials that support DPSC adhesion is used. Based on these findings, thiol-ene chemistry is employed to achieve rapid light-curing and minimize residual monomer of the lead materials. Several triacrylate bulk polymers support DPSC adhesion, proliferation, and differentiation in vitro, and exhibit stiffness and tensile strength similar to existing dental materials. Conversely, materials composed of a trimethacrylate monomer or bisphenol A glycidyl methacrylate, which is a monomer standard in dental materials, do not support stem cell adhesion and negatively impact matrix and signaling pathways. Furthermore, thiol-ene polymerized triacrylates are used as permanent filling materials at the dentin-pulp interface in direct contact with irreversibly injured pulp tissue. These novel triacrylate-based biomaterials have potential to enable novel regenerative dental therapies in the clinic by both restoring teeth and providing a supportive niche for DPSCs. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. The estimation of corrosion behaviour of ZrTi binary alloys for dental applications using electrochemical techniques

    International Nuclear Information System (INIS)

    Mareci, Daniel; Bolat, Georgiana; Chelariu, Romeu; Sutiman, Daniel; Munteanu, Corneliu

    2013-01-01

    Titanium and zirconium are in the same group in the periodic table of elements and are known to have similar physical and chemical properties. Both Ti and Zr usually have their surfaces covered by a thin oxide film spontaneously formed in air. However, the cytotoxicity of ZrO 2 is lower than that of TiO 2 rutile. Treatments with fluoride are known as the main methods to prevent plaque formation and dental caries. The corrosion behaviour of ZrTi alloys with Ti contents of 5, 25 and 45 wt.% and cp-Ti was investigated for dental applications. All samples were tested by linear potentiodynamic polarisation and electrochemical impedance spectroscopy (EIS) performed in artificial saliva with different pH levels (5.6 and 3.4) and different fluoride (1000 ppm F − ) and albumin protein (0.6%) contents. In addition, scanning electron microscopy (SEM) was employed to observe the surface morphology of the test materials after linear potentiodynamic polarisation. The corrosion current densities for the ZrTi alloys increased with the titanium content. The Zr5Ti and Zr25Ti alloys were susceptible to localised corrosion. The role that Ti plays as an alloying element is that of increasing the resistance of ZrTi alloy to localised corrosion. The presence of 0.6% albumin protein in fluoridated acidified artificial saliva with 1000 ppm F − could protect the cp-Ti and ZrTi alloys from attack by fluoride ions. - Highlights: • Electrochemical and corrosion behaviour of the new ZrTi alloys were investigated. • The passive behaviour for all the ZrTi alloys is observed. • Addition of Ti to Zr improves the corrosion resistance in some fluoridated saliva. • The presence of albumin could prevent the ZrTi alloys from attack by fluoride ions

  2. The estimation of corrosion behaviour of ZrTi binary alloys for dental applications using electrochemical techniques

    Energy Technology Data Exchange (ETDEWEB)

    Mareci, Daniel [“Gheorghe Asachi” Technical University of Iasi, Faculty of Chemical Engineering and Environmental Protection, Iasi (Romania); Bolat, Georgiana, E-mail: georgiana20022@yahoo.com [“Gheorghe Asachi” Technical University of Iasi, Faculty of Chemical Engineering and Environmental Protection, Iasi (Romania); Chelariu, Romeu [“Gheorghe Asachi” Technical University of Iasi, Faculty of Materials Science and Engineering, Iasi (Romania); Sutiman, Daniel [“Gheorghe Asachi” Technical University of Iasi, Faculty of Chemical Engineering and Environmental Protection, Iasi (Romania); Munteanu, Corneliu [“Gheorghe Asachi” Technical University of Iasi, Faculty of Mechanical, Iasi (Romania)

    2013-08-15

    Titanium and zirconium are in the same group in the periodic table of elements and are known to have similar physical and chemical properties. Both Ti and Zr usually have their surfaces covered by a thin oxide film spontaneously formed in air. However, the cytotoxicity of ZrO{sub 2} is lower than that of TiO{sub 2} rutile. Treatments with fluoride are known as the main methods to prevent plaque formation and dental caries. The corrosion behaviour of ZrTi alloys with Ti contents of 5, 25 and 45 wt.% and cp-Ti was investigated for dental applications. All samples were tested by linear potentiodynamic polarisation and electrochemical impedance spectroscopy (EIS) performed in artificial saliva with different pH levels (5.6 and 3.4) and different fluoride (1000 ppm F{sup −}) and albumin protein (0.6%) contents. In addition, scanning electron microscopy (SEM) was employed to observe the surface morphology of the test materials after linear potentiodynamic polarisation. The corrosion current densities for the ZrTi alloys increased with the titanium content. The Zr5Ti and Zr25Ti alloys were susceptible to localised corrosion. The role that Ti plays as an alloying element is that of increasing the resistance of ZrTi alloy to localised corrosion. The presence of 0.6% albumin protein in fluoridated acidified artificial saliva with 1000 ppm F{sup −} could protect the cp-Ti and ZrTi alloys from attack by fluoride ions. - Highlights: • Electrochemical and corrosion behaviour of the new ZrTi alloys were investigated. • The passive behaviour for all the ZrTi alloys is observed. • Addition of Ti to Zr improves the corrosion resistance in some fluoridated saliva. • The presence of albumin could prevent the ZrTi alloys from attack by fluoride ions.

  3. Interpenetrating network ceramic-resin composite dental restorative materials.

    Science.gov (United States)

    Swain, M V; Coldea, A; Bilkhair, A; Guess, P C

    2016-01-01

    This paper investigates the structure and some properties of resin infiltrated ceramic network structure materials suitable for CAD/CAM dental restorative applications. Initially the basis of interpenetrating network materials is defined along with placing them into a materials science perspective. This involves identifying potential advantages of such structures beyond that of the individual materials or simple mixing of the components. Observations from a number of recently published papers on this class of materials are summarized. These include the strength, fracture toughness, hardness and damage tolerance, namely to pointed and blunt (spherical) indentation as well as to burr adjustment. In addition a summary of recent results of crowns subjected to simulated clinical conditions using a chewing simulator are presented. These results are rationalized on the basis of existing theoretical considerations. The currently available ceramic-resin IPN material for clinical application is softer, exhibits comparable strength and fracture toughness but with substantial R-curve behavior, has lower E modulus and is more damage tolerant than existing glass-ceramic materials. Chewing simulation observations with crowns of this material indicate that it appears to be more resistant to sliding/impact induced cracking although its overall contact induced breakage load is modest. Copyright © 2015 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  4. No calcium-fluoride-like deposits detected in plaque shortly after a sodium fluoride mouthrinse.

    Science.gov (United States)

    Vogel, G L; Tenuta, L M A; Schumacher, G E; Chow, L C

    2010-01-01

    Plaque 'calcium-fluoride-like' (CaF(2)-like) and fluoride deposits held by biological/bacterial calcium fluoride (Ca-F) bonds appear to be the source of cariostatic concentrations of fluoride in plaque fluid. The aim of this study was to quantify the amounts of plaque fluoride held in these reservoirs after a sodium fluoride rinse. 30 and 60 min after a 228 microg/g fluoride rinse, plaque samples were collected from 11 volunteers. Each sample was homogenized, split into 2 aliquots (aliquots 1 and 2), centrifuged, and the recovered plaque fluid combined and analyzed using microelectrodes. The plaque mass from aliquot 1 was retained. The plaque mass from aliquot 2 was extracted several times with a solution having the same fluoride, calcium and pH as the plaque fluid in order to extract the plaque CaF(2)-like deposits. The total fluoride in both aliquots was then determined. In a second experiment, the extraction completeness was examined by applying the above procedure to in vitro precipitates containing known amounts of CaF(2)-like deposits. Nearly identical fluoride concentrations were found in both plaque aliquots. The extraction of the CaF(2)-like precipitates formed in vitro removed more than 80% of these deposits. The results suggest that either CaF(2)-like deposits were not formed in plaque or, if these deposits had been formed, they were rapidly lost. The inability to form persistent amounts of CaF(2)-like deposits in plaque may account for the relatively rapid loss of plaque fluid fluoride after the use of conventional fluoride dentifrices or rinses. (c) 2010 S. Karger AG, Basel.

  5. Influência de diferentes concentrações de flúor na água em indicadores epidemiológicos de saúde/doença bucal Influence of different concentrations of fluoride in the water on epidemiologic indicators of oral health/disease

    Directory of Open Access Journals (Sweden)

    Raquel Baroni de Carvalho

    2011-08-01

    Full Text Available O objetivo deste estudo foi avaliar o acesso a fontes de fluoreto e as condições de saúde bucal de 237 escolares de nove a dezesseis anos, de três localidades com diferentes concentrações de fluoreto na água. O teor de flúor na água de cada região foi analisado pela técnica do eletrodo seletivo para o íon flúor e a foi avaliada prevalência de cárie e fluorose, respectivamente, pelo índice CPOD e TSIF, apresentando diferença estatisticamente significante (ANOVA; p The scope of this study was to evaluate access to fluoride sources and oral health hygiene of 237 schoolchildren aged nine to sixteen, from three locations with different fluoride concentrations in the water. The fluoride level in the water of each area was analyzed by the selective electrode technique for the fluoride ion and the prevalence of dental caries and fluorosis were evaluated, respectively, by the DMFT and TSIF index, revealing a statistically significant difference (ANOVA; p <0,05 in the three locations: area without artificial fluoridation (DMTF 5.32 ± 3.49 and 16% of dental fluorosis; area with artificial fluoridation of 0.8 ppmF (DMTF 1.88 ± 2.22 and 94% of dental fluorosis; area with natural fluoridation of 2.54 ppmF (DMTF 3.96 ± 2.38 and 100% of dental fluorosis. The findings suggest that the epidemiologic indicators of oral health/disease are influenced by the presence of fluoride in the water supply and that supervision and orientation are fundamental in the correct use of fluoridated compositions, taking advantage of the maximum benefit in the control of dental caries with minimum risk of the occurrence of dental fluorosis.

  6. FLUORIDE CONTENT OF COMMERCIALLY AVAILABLE SOY MILK PRODUCTS IN THAILAND.

    Science.gov (United States)

    Rirattanapong, Opas; Rirattanapong, Praphasri

    2016-01-01

    Abstract. In Thailand, the consumption of soy milk products is common but there is limited data about their fluoride content. The purpose of this study was to es- timate the fluoride content of soy milk products available in Thailand. Fluoride content was determined for 76 brands of soy milk using a F-ion-specific electrode. The fluoride concentrations ranged from 0.01 to 3.78 μg/ml. The fluoride content was not related to sugar content, soy bean content or the sterilization process. Among 3 brands of soy milk containing tea powder extract, the fluoride content was high (1.25 to 3.78 μg/ml). Most brands of soy milk tested in our study had fluoride content below the optimal daily intake but brands containing tea powder extract if consumed by children may increase their risk for fluorosis.

  7. Protocol for Northern Ireland Caries Prevention in Practice Trial (NIC-PIP trial: a randomised controlled trial to measure the effects and costs of a dental caries prevention regime for young children attending primary care dental services

    Directory of Open Access Journals (Sweden)

    Noble Solveig

    2011-10-01

    Full Text Available Abstract Background Dental caries is a persistent public health problem with little change in the prevalence in young children over the last 20 years. Once a child contracts the disease it has a significant impact on their quality of life. There is good evidence from Cochrane reviews including trials that fluoride varnish and regular use of fluoride toothpaste can prevent caries. The Northern Ireland Caries Prevention in Practice Trial (NIC-PIP trial will compare the costs and effects of a caries preventive package (fluoride varnish, toothpaste, toothbrush and standardised dental health education with dental health education alone in young children. Methods/Design A randomised controlled trial on children initially aged 2 and 3 years old who are regular attenders at the primary dental care services in Northern Ireland. Children will be recruited and randomised in dental practices. Children will be randomised to the prevention package of both fluoride varnish (twice per year for three years, fluoride toothpaste (1,450 ppm F (supplied twice per year, a toothbrush (supplied twice a year or not; both test and control groups receive standardised dental health education delivered by the dentist twice per year. Randomisation will be conducted by the Belfast Trust Clinical Research Support Centre ([CRSC] a Clinical Trials Unit. 1200 participants will be recruited from approximately 40 dental practices. Children will be examined for caries by independent dental examiners at baseline and will be excluded if they have caries. The independent dental examiners will examine the children again at 3 years blinded to study group. The primary end-point is whether the child develops caries (cavitation into dentine or not over the three years. One secondary outcome is the number of carious surfaces in the primary dentition in children who experience caries. Other secondary outcomes are episodes of pain, extraction of primary teeth, other adverse events and costs

  8. Protocol for Northern Ireland Caries Prevention in Practice Trial (NIC-PIP) trial: a randomised controlled trial to measure the effects and costs of a dental caries prevention regime for young children attending primary care dental services

    LENUS (Irish Health Repository)

    Tickle, Martin

    2011-10-10

    Abstract Background Dental caries is a persistent public health problem with little change in the prevalence in young children over the last 20 years. Once a child contracts the disease it has a significant impact on their quality of life. There is good evidence from Cochrane reviews including trials that fluoride varnish and regular use of fluoride toothpaste can prevent caries. The Northern Ireland Caries Prevention in Practice Trial (NIC-PIP) trial will compare the costs and effects of a caries preventive package (fluoride varnish, toothpaste, toothbrush and standardised dental health education) with dental health education alone in young children. Methods\\/Design A randomised controlled trial on children initially aged 2 and 3 years old who are regular attenders at the primary dental care services in Northern Ireland. Children will be recruited and randomised in dental practices. Children will be randomised to the prevention package of both fluoride varnish (twice per year for three years), fluoride toothpaste (1,450 ppm F) (supplied twice per year), a toothbrush (supplied twice a year) or not; both test and control groups receive standardised dental health education delivered by the dentist twice per year. Randomisation will be conducted by the Belfast Trust Clinical Research Support Centre ([CRSC] a Clinical Trials Unit). 1200 participants will be recruited from approximately 40 dental practices. Children will be examined for caries by independent dental examiners at baseline and will be excluded if they have caries. The independent dental examiners will examine the children again at 3 years blinded to study group. The primary end-point is whether the child develops caries (cavitation into dentine) or not over the three years. One secondary outcome is the number of carious surfaces in the primary dentition in children who experience caries. Other secondary outcomes are episodes of pain, extraction of primary teeth, other adverse events and costs which will

  9. Quantification of trace level of fluoride content in uranium oxide produced by deconversion of HEX gas by ion chromatography

    International Nuclear Information System (INIS)

    Unnikrishnan, E.K.; Padmakumar, P.R.; Shanmugavelu, P.; Sudhakar, T.M.; Bhowmik, A.

    2015-01-01

    Fluoride content in nuclear fuel is detrimental due to its corrosion behavior with cladding material. It is essential to monitor and control the fluoride concentration in nuclear material at various processing stages. Deconversion of upgraded HEX gas is carried out to produce uranium oxide. The performance of the deconversion process of HEX gas is evaluated for which trace level of fluoride concentration accompanying uranium oxide is considered as a marker. An analytical method has been developed for testing the uranium oxide produced from deconversion process of HEX gas. The method involves sample pretreatment followed by analysis using ion chromatography. The test method was validated for its performance using in house synthetic uranyl fluoride (UO 2 F 2 ) standard solutions prepared with different level of fluoride content. The results are in agreement with the expected values with the recovery in the range of 80-95%. This method has been successfully implemented for routine analysis of samples at our lab. Since UO 2 F 2 reference material is not available to validate this method, in house UO 2 F 2 standards were prepared from U 3 O 8 prepared from nuclear grade uranyl nitrate solution. UO 2 F 2 standards were prepared by converting U 3 O 8 to UO 2 F 2 by the addition of HF followed by H 2 O 2 at 200°C on a hot plate. The entire yellow colored UO 2 F 2 was dissolved in nano pure water and recrystallised several times to ensure that all free HF is removed. The crystals dried in air oven at 120° for three hours. Samples containing 1000 mg kg -1 fluoride prepared from this UO 2 F 2 , and subsequently from this sample containing 5 mg kg -1 to 35 mg kg -1 fluoride samples were prepared and analysed against fluoride CRM and the fluoride concentration obtained was analysed

  10. Legal analysis of information displayed on dental material packages: An exploratory research

    Directory of Open Access Journals (Sweden)

    Bhumika Rathore

    2016-01-01

    Full Text Available Introduction: Some of the dental materials possess occupational hazards, preprocedural errors, and patient allergies as suggested by evidence. With due consideration to safety of the patients and dental professionals, it is essential that the trade of these materials is in conformity with the law. Aim: To perform the legal analysis of the information displayed on the packaging of dental materials. Materials and Methods: The Bureau of Indian Standards sets guidelines for packaging and marketing of dental products in India. An exploratory cross-sectional study was performed using various search engines and websites to access the laws and regulations existing pertaining to dental materials packaging. Based on the data obtained, a unique packaging standardization checklist was developed. Dental laboratory and impression plasters, alginates, and endodontic instruments were surveyed for all the available brands. This study considered 16 brands of plasters and alginates and 42 brands of endodontic instruments for legal analysis. Legal analysis was performed using the direct observation checklist. Descriptive statistics were obtained using SPSS version 19. Results: The guidelines set by the Bureau of Indian Standards do exist but are not updated and stand as oblivious guards for marketing standards. Overall compliance to the guidelines was reported to be 18.5% by brands of alginates, 4.1% by plaster of Paris, and 11.11% by endodontic instruments. Wave One™ File reported maximum adherence with the guidelines as 66.7%. Conclusion: This study found lower rate of adherence to the guidelines, thus indicating insufficient information being disclosed to the consumers.

  11. Assessment of fluoride in groundwater and urine, and prevalence of fluorosis among school children in Haryana, India

    Science.gov (United States)

    Haritash, A. K.; Aggarwal, Ankur; Soni, Jigyasa; Sharma, Khyati; Sapra, Mohnish; Singh, Bhupinder

    2018-05-01

    Considering the health effects of fluoride, the present study was undertaken to assess the concentration of fluoride in groundwater, and urine of school children in Bass region of Haryana state. Fluoride in groundwater was observed to vary from 0.5 to 2.4 mg/l with an average concentration of 0.46 mg/l. On the other hand, F- in urine ranged from below the detection limit to 1.8 mg/l among girls and 0.17-1.2 mg/l among the boys. Higher average concentration of fluoride in urine (0.65 mg/l for boys and 0.34 mg/l for girls) may be ascribed to exposure to bioavailable fluoride through food, milk, tea, toothpaste, etc., in addition to intake through groundwater. Relatively more intake of water and food by the boys might be the reason for more cases of severe dental fluorosis (44%) among boys compared to girls (29% cases of moderate to severe dental fluorosis). The groundwater quality for drinking was compromised with respect to dissolved solids, hardness, magnesium ions, and dissolved iron. Hydro-geochemical investigation revealed that rock-water interaction, in terms of direct cation exchange, dominantly regulates groundwater chemistry, and groundwater is of Ca-Na-HCO3 type.

  12. Effect of fluoride pretreatment on the solubility of synthetic carbonated apatite.

    Science.gov (United States)

    Barry, A B; Zhuang, H; Baig, A A; Higuchi, W I

    2003-03-01

    The purpose of this research was to address the following question: How is the solubility of fluoride-pretreated carbonated apatite (CAP) in aqueous acidic media related to the equilibrium solution fluoride and/or the CAP adsorbed fluoride levels? A CAP sample prepared by a precipitation method at 70 degrees C containing approximately 6% carbonate was fluoride-treated (F adsorption from neutral aqueous solutions) to yield a approximately 1000 ppm F CAP and a approximately 3300 ppm F CAP. Metastable equilibrium solubility distributions were determined in acetate buffers at pH 5.0. Solution fluoride, calcium, phosphate, and pH were determined from the equilibrated solutions. The equilibrium solution fluoride levels were extremely low, e.g., as low as approximately 0.10 ppb to approximately 0.30 ppb at 50% dissolved for the two CAP preparations. The approximately 3300 ppm F CAP yielded a lower solubility than the approximately 1000 ppm F CAP (shift in the mean pKHAP value of 1.5-2 units). This can be attributed to the lower solution F(-) for the sample containing approximately 1000 ppm fluoride compared with the approximately 3300 ppm fluoride-containing CAP. These important findings suggest that a fluoride treatment simply may provide an adsorption fluoride depot for subsequent release, providing a solution fluoride effect upon the CAP solubility and not necessarily any intrinsic alteration of the mineral solubility.

  13. A review of the literature: the economic impact of preventive dental hygiene services.

    Science.gov (United States)

    Sharon, Stull C; Connolly, Irene M; Murphree, Kellie R

    2005-01-01

    The contributions of dental hygiene as a discipline of prevention, the inception of systemic fluoride in community water systems, the continual research conducted by the National Institute of Dental and Craniofacial Research (NIDCR), and the success of dental sealants have all contributed to the decrease in incidences of dental diseases. The prevalence of employer-based dental insurance must also be recognized as contributing to a substantial paradigm shift on the utilization of oral health preventive services. This review of the economic impact of oral health preventive services on the consumer and the private dental practice suggests that these services have had a significant impact. Dentistry's challenge remains to extend these considerable gains in oral health status to the 150 million U.S. citizens who do not have access to oral health care services identified in the 2000 Oral Health in America: A Report of the Surgeon General. Utilizing preventive, therapeutic, and educational aspects of dental hygiene services, reaching communities without fluoridation of the public water supply, and incorporating mass pediatric dental sealant programs analogous to immunization programs would improve the oral health status of underserved populations.

  14. Approaches to the accurate characterization of high purity metal fluorides and fluoride glasses

    Science.gov (United States)

    Beary, E. S.; Paulsen, P. J.; Rains, T. C.; Ewing, K. J.; Jaganathan, J.; Aggarwal, I.

    1990-11-01

    The analytical challenges posed by the measurement of trace contaminants in high purity metal fluorides require that innovative chemical preparation procedures be used to enhance existing instrumental techniques. The instrumental techniques used to analyze these difficult matrices must be sensitive enough to detect extremely low levels of trace impurities, and the background interferences derived from the matrix (metal fluoride or glass) must be minimized. A survey of analytical techniques that have the necessary characteristics to analyze these materials will be given. In addition, means of controlling the chemical blank will be presented. Mass and atomic spectrometric techniques will be discussed, specifically graphite furnace atomic absorption spectrometry (GFAAS) and inductively coupled plasma-mass spectrometry (ICP-MS). Analytical procedures using GFAAS and ICP-MS have been developed to determine sub ppb (part per billion) levels of contaminants in high purity fluoride materials.

  15. Optimizing School-Based Health-Promotion Programmes: Lessons from a Qualitative Study of Fluoridated Milk Schemes in the UK

    Science.gov (United States)

    Foster, Geraldine R. K.; Tickle, Martin

    2013-01-01

    Background and objective: Some districts in the United Kingdom (UK), where the level of child dental caries is high and water fluoridation has not been possible, implement school-based fluoridated milk (FM) schemes. However, process variables, such as consent to drink FM and loss of children as they mature, impede the effectiveness of these…

  16. Fluoride materials for high peak power lasers, 17 May 1976--31 January 1977

    International Nuclear Information System (INIS)

    Folweiler, R.C.

    1977-02-01

    Single crystal fluoride optical materials were grown for potential application to laser fusion. Fluoride materials are of interest for this application, in general, because their low non-linear indices of refraction permit their use in optical components which can sustain very high peak powers without causing beam distortion. Emphasis was placed on Nd:YLF because its emission wave-lengths match the gain curve of promising amplifier materials. In addition to material growth, new feed preparation techniques were investigated and developed and certain material properties measured. The laser material, Nd:YLF, (Nd 3+ in LiYF 4 ) was grown and fabricated into laser rods. This material has laser emission at 1.047 μm and 1.053 μm, depending on the polarization selected. The former wavelength matches the peak emission wavelength of developmental Nd fluoroberyllate glasses, the latter matches Nd phosphate and fluorophosphate glasses that have low values of n 2 . The non-linear index of pure LiYF 4 was measured by Milam and Weber as 0.59 x 10 -13 esu. The concentration of Nd 3+ was varied from 1% to 4%. At higher concentrations and larger diameters a radial strain was found, sufficient to cause spiral cracking. This strain was apparently generated by a radial gradient of Nd 3+ ions. The distribution coefficient observed in one sample was 0.38. The stimulation emission coefficients were determined. Boules of KY 3 F 10 and KTb 3 F 10 were grown, with the latter suitable as a Faraday rotator material with projected low n 2 and larger Verdet constant. Experiments were performed on the systemKF-CeF 3 as a potential Faraday rotator material, and a cubic phase observed. The Ce 3+ ion has slightly lower rotary power/ion, but significantly lower cost

  17. Effect of Iron Containing Supplements on Rats' Dental Caries Progression

    Directory of Open Access Journals (Sweden)

    AR. Eshghi

    2012-01-01

    Full Text Available Objective: Iron deficiency is the most common form of malnutrition in developing countries. Iron containing supplements have been used effectively to solve this problem. In children, because of teeth staining after taking iron drops, parents have the idea that iron drops are the cause of tooth decay; therefore, they limit thisvital supplement in their children’s diet. Hereby, we evaluate the histologic effect of iron containing supplements on tooth caries in rice rats with cariogenic or noncariogenic diet.Materials and Methods: Twelve rats were selected and divided into four groups for this interventional experimental study. Four different types of dietary regimens were used for four months; group A, cariogenic diet with iron containing supplements; group B, cariogenic diet without iron containing supplements; groupC, non-cariogenic diet with iron containing supplements; group D, non-cariogenic diet without iron containing supplements. After sacrificing the rats, 20-micron histological sections of their posterior teeth were prepared using the Ground Sectionmethod, then they were studied under polarized light microscopy. In order to compare the progression of caries in different samples, the depth of the lesions in the enamel was measured as three grades I, II and III.Results: The mean grade value of A, B, C and D groups were 1.61, 2.61, 1.37 and 1.80, respectively. Statistical analysis revealed that significantly fewer caries were seen in the group which had received iron containing supplements and cariogenicdiet compared with cariogenic diet without iron supplements (p<0.05.Conclusion: Ferrous sulfate reduces the progression of dental caries in the cariogenic dietary regimen.

  18. Effect of four dental varnishes on the colonization of cariogenic bacteria on exposed sound root surfaces.

    Science.gov (United States)

    Ekenbäck, S B; Linder, L E; Lönnies, H

    2000-01-01

    The aim of this study was to evaluate the effect of four different dental varnishes on the colonization of mutans streptococci, total streptococci and lactobacilli on exposed sound root surfaces. Sixty-five individuals were randomly allotted to one of four groups for treatment with Cervitec((R) ) varnish containing 1% chlorhexidine and 1% thymol, a thymol varnish or one of two different fluoride varnishes, Fluor Protector and Duraphat. The varnish was applied to three buccal root surfaces in each patient at baseline and after 1 week. Dental plaque from the root surfaces was collected and analysed on four different occasions: at baseline, after 1 week, 1 month and 6 months. The Cervitec varnish caused a statistically significant reduction in the number of mutans streptococci over time. The reduction was significant at 1 week and 1 month relative to baseline. The numbers of total streptococci and lactobacilli were not significantly affected by treatment with Cervitec. No statistically significant difference over time was found for mutans streptococci, lactobacilli or total streptococci after treatment with the fluoride varnishes or the thymol varnish.

  19. Competitive light absorbers in photoactive dental resin-based materials.

    Science.gov (United States)

    Hadis, Mohammed A; Shortall, Adrian C; Palin, William M

    2012-08-01

    The absorbance profile of photoinitiators prior to, during and following polymerization of light curable resin-based materials will have a significant effect on the cure and color properties of the final material. So-called "colorless" photoinitiators are used in some light-activated resin-based composite restorative materials to lessen the yellowing effect of camphoroquinone (CQ) in order to improve the esthetic quality of dental restorations. This work characterizes absorption properties of commonly used photoinitiators, an acylphosphine oxide (TPO) and CQ, and assesses their influence on material discoloration. Dimethacrylate resin formulations contained low (0.0134 mol/dm(3)), intermediate (0.0405 mol/dm(3)) or high (0.0678 mol/dm(3)) concentrations of the photoinitiators and the inhibitor, butylated hydroxytoluene (BHT) at 0, 0.1 or 0.2% by mass. Disc shaped specimens (n = 3) of each resin were polymerized for 60s using a halogen light curing unit. Dynamic measurements of photoinitiator absorption, polymer conversion and reaction temperature were performed. A spectrophotometer was used to measure the color change before and after cure. GLM three-way analysis of variance revealed significant differences (pphotoinitiator type (df = 1; F = 176.12)>% BHT (df = 2, F = 13.17). BHT concentration affected the rate of polymerization and produced lower conversion in some of the CQ-based resins. Significant differences between photoinitiator type and concentrations were seen in color (where TPO resins became yellower and camphoroquinone resins became less yellow upon irradiation). Reaction temperature, kinetics and conversion also differed significantly for both initiators (presins producing a visually perceptible color change upon polymerization, the color change was significantly less than that produced with CQ-based resins. Although some photoinitiators such as TPO may be a more esthetic alternative to CQ, they may actually cause significant color contamination when

  20. A quantitative look at fluorosis, fluoride exposure, and intake in children using a health risk assessment approach.

    Science.gov (United States)

    Erdal, Serap; Buchanan, Susan N

    2005-01-01

    The prevalence of dental fluorosis in the United States has increased during the last 30 years. In this study, we used a mathematical model commonly employed by the U.S. Environmental Protection Agency to estimate average daily intake of fluoride via all applicable exposure pathways contributing to fluorosis risk for infants and children living in hypothetical fluoridated and nonfluoridated communities. We also estimated hazard quotients for each exposure pathway and hazard indices for exposure conditions representative of central tendency exposure (CTE) and reasonable maximum exposure (RME) conditions. The exposure pathways considered were uptake of fluoride via fluoridated drinking water, beverages, cow's milk, foods, and fluoride supplements for both age groups. Additionally, consumption of infant formula for infants and inadvertent swallowing of toothpaste while brushing and incidental ingestion of soil for children were also considered. The cumulative daily fluoride intake in fluoridated areas was estimated as 0.20 and 0.11 mg/kg-day for RME and CTE scenarios, respectively, for infants. On the other hand, the RME and CTE estimates for children were 0.23 and 0.06 mg/kg-day, respectively. In areas where municipal water is not fluoridated, our RME and CTE estimates for cumulative daily average intake were, respectively, 0.11 and 0.08 mg/kg-day for infants and 0.21 and 0.06 mg/kg-day for children. Our theoretical estimates are in good agreement with measurement-based estimates reported in the literature. Although CTE estimates were within the optimum range for dental caries prevention, the RME estimates were above the upper tolerable intake limit. This suggests that some children may be at risk for fluorosis.

  1. Fluoride removal from aqueous solution by pumice: case study on ...

    African Journals Online (AJOL)

    EJIRO

    conditions, the fluoride removal efficiency from Kuhbonan water by 2.8 mg/L fluoride was 74.64%. Eventually ... industrial wastewater containing fluoride is a key ..... solution using silica ceramic: Adsorption kinetics and equilibrium studies.

  2. Dental ceramics: a review of new materials and processing methods.

    Science.gov (United States)

    Silva, Lucas Hian da; Lima, Erick de; Miranda, Ranulfo Benedito de Paula; Favero, Stéphanie Soares; Lohbauer, Ulrich; Cesar, Paulo Francisco

    2017-08-28

    The evolution of computerized systems for the production of dental restorations associated to the development of novel microstructures for ceramic materials has caused an important change in the clinical workflow for dentists and technicians, as well as in the treatment options offered to patients. New microstructures have also been developed by the industry in order to offer ceramic and composite materials with optimized properties, i.e., good mechanical properties, appropriate wear behavior and acceptable aesthetic characteristics. The objective of this literature review is to discuss the main advantages and disadvantages of the new ceramic systems and processing methods. The manuscript is divided in five parts: I) monolithic zirconia restorations; II) multilayered dental prostheses; III) new glass-ceramics; IV) polymer infiltrated ceramics; and V) novel processing technologies. Dental ceramics and processing technologies have evolved significantly in the past ten years, with most of the evolution being related to new microstructures and CAD-CAM methods. In addition, a trend towards the use of monolithic restorations has changed the way clinicians produce all-ceramic dental prostheses, since the more aesthetic multilayered restorations unfortunately are more prone to chipping or delamination. Composite materials processed via CAD-CAM have become an interesting option, as they have intermediate properties between ceramics and polymers and are more easily milled and polished.

  3. Toothpaste use protocol with dental bleaching for a conservative treatment: Case reports

    Directory of Open Access Journals (Sweden)

    Waldemir F. Vieira-Junior

    2017-01-01

    Full Text Available In-office bleaching is a treatment based on products that contain hydrogen peroxide (HP while demonstrating whitening effectiveness. HP could promote alterations to surface morphologies and properties of dental tissues. The objective was describe a toothpaste protocol associated to bleaching therapy to promote a safer approach. Patient 1 (male and Patient 2 (female were attended, and toothbrushing (twice a day with a dentifrice containing bioactive glass (BG (NovaMin™ and fluoride was indicated before and during the treatment. Three bleaching sessions were made in cases, at intervals of 7 days. The gels used were 35% HP (Patient 1 and 35% HP supplied with calcium (Patient 2. The effectiveness of bleaching treatment was observed in both cases (Vita scale, with an esthetic self-acceptance. Sensitivity associated with the procedure was not reported. The indication of BG-based toothpaste is relevant in relation to enamel properties and did not affect the whitening effectiveness of dental bleaching.

  4. Low-dose dental CT

    International Nuclear Information System (INIS)

    Rustemeyer, P.; Eich, H.T.; John-Mikolajewski, V.; Mueller, R.D.

    1999-01-01

    Purpose: The intention of this study was to reduce patient dose during dental CT in the planning for osseointegrated implants. Methods and Materials: Dental CTs were performed with a spiral CT (Somatom Plus 4, Siemens) and a dental software package. Use of the usual dental CT technique (120 kVp; 165 mA, 1 s rotation time, 165 mAs; pitch factor 1) was compared with a new protocol (120 kVp; 50 mA; 0.7 s rotation time; 35 mAs; pitch factor 2) which delivered the best image quality at the lowest possible radiation dose, as tested in a preceding study. Image quality was analysed using a human anatomic head preparation. Four radiologists analysed the images independently. A Wilcoxon rank pair-test was used for statistic evaluation. The doses to the thyroid gland, the active bone marrow, the salivary glands, and the eye lens were determined in a tissue-equivalent phantom (Alderson-Rando Phantom) with lithium fluoride thermoluminescent dosimeters at the appropriate locations. Results: By mAs reduction from 165 to 35 and using a pitch factor of 2, the radiation dose could be reduced by a factor of nine (max.) (e.g., the bone marrow dose could be reduced from 23.6 mSv to 2.9 mSv, eye lens from 0.5 mSv to 0.3 mSv, thyroid gland from 2.5 mSv to 0.5 mSv, parotid glands from 2.3 mSv to 0.4 mSv). The dose reduction did not lead to an actual loss of image quality or diagnostic information. Conclusion: A considerable dose reduction without loss of diagnostic information is achievable in dental CT. Dosereducing examination protocols like the one presented may further expand the use of preoperative dental CT. (orig.) [de

  5. Solubility and fluoride release in ionomers and compomers.

    Science.gov (United States)

    Bertacchini, S M; Abate, P F; Blank, A; Baglieto, M F; Macchi, R L

    1999-03-01

    The degree of solubility and the fluoride release of glass-ionomer cements and "compomers" were determined as a function of time. Three conventional glass-ionomer cements, three hybrid ionomers, and two compomers were included in the study. Disk-shaped specimens were prepared and immersed in a lactic acid solution. Solubility was evaluated from determinations of loss of mass as a function of time. To evaluate fluoride release, similar specimens were immersed in 50 mL of deionized water to which 50 mL of buffer solution was added. A fluoride ion detector was used to read the concentration of fluoride ion in the overall solution at different times after immersion. Material and time factors had a significant influence on results. The compomers showed less corrosion and fluoride release than the ionomers. Some correlation was found between solubility and fluoride leakage values. Components of both the ionomers and compomers that were studied can dissolve in water. The materials leak fluoride ions in amounts that differ according to the characteristics of the individual products.

  6. Hydrogeochemical framework and factor analysis of fluoride contamination in Groundwater within the Savelugu-Nanton District, Northern Ghana

    International Nuclear Information System (INIS)

    Tay, Collins K.

    2017-01-01

    Fluoride contamination of groundwater within the Savelugu-Nanton District was assessed using hydrogeochemical framework and multivariate statistical approach. Eighty-one (No) boreholes were sampled for quality assessment in May and June 2008. The main objective of this study was to assess the fluoride levels in groundwater and delineate areas of low fluoride and high fluoride within the district. The study show that, 41.9% of the boreholes are within the safe limits of 0.5 –1.5 mg/L of fluoride for the protection of bones and teeth, 43.2% of the boreholes have fluoride levels below the lower safe limit (< 0.5 mg/L) and therefore vulnerable to dental caries, 10.8% of the boreholes have fluoride levels between 1.5 and 3.0 mg/Land therefore vulnerable to dental fluorosis and 4.1% of the boreholes have fluoride levels between 3.0 and 10 mg/L and therefore vulnerable to skeletal fluorosis. The results further show that, 14.9% of groundwater requires defluoridation, while, 43.2% of groundwater requires fluoride addition to the groundwaters. PCA using Varimax with Kaiser Normalization results in the extraction of three main principal components which delineates the factors that influence the principal components of the physico-chemical parameters. The three principal components have accounted for approximately 83% of the total variance. Component 1 delineates the main natural processes through which groundwater within the basin acquire its chemical characteristics. Component 2 delineates pollution sources principally fluoride and nitrate. Component 3 suggests mineralogical influence of fluoride with some major ions on the chemistry of groundwater. The loadings and score plots of the first two PCs which explains 71.52% of the total variance show grouping pattern which indicates the strength of the mutual relation amongst the hydrochemical variables. Biological defluoridation though not very well understood, is recommended as a best alternative to the conventional methods

  7. Dental hygiene students' part-time jobs in dental practices in the Netherlands.

    Science.gov (United States)

    Poorterman, J H G; Dikkes, B T; Brand, H S

    2010-05-01

    Many students have paid employment while studying. In the Netherlands, the Individual Health Care Professions Act (IHCP Act) allows dental hygiene students to work under certain conditions in a dental practice. The aim of the study was to determine how many dental hygiene students have part-time job employment in dental practice and which professional tasks they carry out. We also asked the dental hygiene students their opinion of the IHCP Act. All the enrolled dental hygiene students (n = 341) at a School of Health in the Netherlands received a questionnaire by email. The response was 52% (176 students). Of the responding students, 75% had paid employment in addition to their study. A proportion of the students (35%) worked in a dental practice. The median number of hours worked per week was eight. Study year, age and prior education were positively related to working part-time in dental practice. Activities frequently performed were giving oral hygiene instruction, fluoride applications, scaling and root planning, providing chair side assistance and giving local anaesthesia. Although the self-reported knowledge about the IHCP Act was high, almost half of the students expressed the need for more detailed legal information. Many dental hygiene students work in a dental practice, taking over a number of tasks usually performed by the dentist. More information in the dental hygiene curriculum about the requirements of the IHCP Act seems desirable.

  8. Effect of fluoride varnish on Streptococcus mutans counts in plaque of caries-free children using dentocult SM strip mutans test: A randomized controlled triple blind study

    Directory of Open Access Journals (Sweden)

    Jeevarathan J

    2007-01-01

    Full Text Available Dental caries is one of the most prevalent infectious diseases and although of multifactorial origin, Streptococcus mutans is considered the chief pathogen in its development. Fluoride is one of the most effective agents used for the reduction of dental caries apart from oral hygiene maintenance. Aims: The aim of this study was to estimate the counts of Streptococcus mutans and to evaluate the effect of Fluor Protector fluoride varnish on these counts in the plaque of caries-free children using Dentocult SM Strip Mutans. Materials and Methods: Thirty caries-free subjects were selected for the study based on the information obtained from a questionnaire and were randomly assigned to the control group consisting of ten subjects and the study group consisting of twenty subjects. Plaque samples were collected on the strips from the Dentocult SM kit and after incubation, the presence of Streptococcus mutans was evaluated using the manufacturer′s chart. The study group was subjected to a Fluor Protector fluoride varnish application following which the samples were collected again after 24 hours. Results: The average Streptococcus mutan s counts in the primary dentition of caries-free children before and after the application of Fluor Protector fluoride varnish were 10 4 -10 5 colony forming units (CFU/ml and < 10 4 CFU/ml respectively. Conclusion: The results showed that the study group had a statistically significant reduction in the plaque Streptococcus mutans counts than the control group.

  9. Evaluation of crystalline changes and resistance to demineralization of the surface of human dental enamel treated with Er:YAG laser and fluoride using x-ray diffraction analysis and Vickers microhardness

    Science.gov (United States)

    Behroozibakhsh, Marjan; Shahabi, Sima; Ghavami-Lahiji, Mehrsima; Sadeghian, Safura; Sadat Faal Nazari, Neda

    2018-06-01

    This study aimed to investigate the changes in crystalline structure and resistance to demineralization of human dental surface enamel treated with erbium-doped yttrium aluminium garnet laser (Er:YAG) laser and fluoride. The enamel surfaces were divided into four groups according to the treatment process including, (L): irradiated with Er:YAG; (F): treated with acidulated phosphate fluoride gel (LF): Pre-irradiated surfaces with Er:YAG subjected to acidulated phosphate fluoride gel and (FL): laser irradiation was performed on the fluoridated enamel surface. Before and after the treatment procedure, the samples were evaluated using X-ray diffraction, scanning electron microscope (SEM) and the Vickers microhardness test. The surface microhardness values also were measured after a pH-cycling regime and acid challenge. The a-axis of all lased groups was contracted after treatment procedure. Measurement of the area under the peaks showed the highest crysallinity in the FL group. The hardness values of all laser treated samples significantly reduced after treatment procedure compared to the F group (p  ⩽  0.001). The morphological observations showed remarkable changes on the lased enamel surfaces including cracks, craters and exposed prisms. These findings suggest, irradiation of the Er:YAG laser accompanying with fluoride application can induce some beneficial crystalline changes regarding the acid-resistance properties of enamel, however, the craters and cracks produced by laser irradiation can promote enamel demineralization and consequently the positive effects of the Er:YAG laser will be eliminated.

  10. Microbiologic aspects of dental plaque and dental caries.

    Science.gov (United States)

    Marsh, P D

    1999-10-01

    Dental plaque is an example of a microbial biofilm with a diverse microbial composition; it is found naturally on teeth and confers advantages to the host, for example, by preventing colonization by exogenous, and often pathogenic, micro-organisms. In individuals with a high frequency sugar diet, or with a severely compromised saliva flow, the levels of potentially cariogenic bacteria (acid-producing and acid-tolerating species) can increase beyond those compatible with enamel health. This article discusses antimicrobial strategies to control dental caries, including; reducing plaque levels, in general or specific cariogenic bacteria in particular, by antiplaque or antimicrobial agents; reducing bacterial acid production by replacing fermentable carbohydrates in the diet with sugar substitutes, or by interfering with bacterial metabolism with fluoride or antimicrobial agents.

  11. Fluoride absorption: independence from plasma fluoride levels

    International Nuclear Information System (INIS)

    Whitford, G.M.; Williams, J.L.

    1986-01-01

    The concept that there are physiologic mechanisms to homeostatically regulate plasma fluoride concentrations has been supported by results in the literature suggesting an inverse relationship between plasma fluoride levels and the absorption of the ion from the gastrointestinal tract of the rat. The validity of the relationship was questioned because of possible problems in the experimental design. The present work used four different methods to evaluate the effect of plasma fluoride levels on the absorption of the ion in rats: (i) the percentage of the daily fluoride intake that was excreted in the urine; (ii) the concentration of fluoride in femur epiphyses; (iii) the net areas under the time-plasma fluoride concentration curves after intragastric fluoride doses; and (iv) the residual amounts or fluoride in the gastrointestinal tracts after the intragastric fluoride doses. None of these methods indicated that plasma fluoride levels influence the rate or the degree or fluoride absorption. It was concluded that, unless extremely high plasma fluoride levels are involved (pharmacologic or toxic doses), the absorption of the ion is independent of plasma levels. The results provide further evidence that plasma fluoride concentrations are not homeostatically regulated

  12. Development of a novel resin-based dental material with dual biocidal modes and sustained release of Ag+ ions based on photocurable core-shell AgBr/cationic polymer nanocomposites.

    Science.gov (United States)

    Cao, Weiwei; Zhang, Yu; Wang, Xi; Chen, Yinyan; Li, Qiang; Xing, Xiaodong; Xiao, Yuhong; Peng, Xuefeng; Ye, Zhiwen

    2017-07-01

    Research on the incorporation of cutting-edge nano-antibacterial agent for designing dental materials with potent and long-lasting antibacterial property is demanding and provoking work. In this study, a novel resin-based dental material containing photocurable core-shell AgBr/cationic polymer nanocomposite (AgBr/BHPVP) was designed and developed. The shell of polymerizable cationic polymer not only provided non-releasing antibacterial capability for dental resins, but also had the potential to polymerize with other methacrylate monomers and prevented nanoparticles from aggregating in the resin matrix. As a result, incorporation of AgBr/BHPVP nanocomposites did not adversely affect the flexural strength and modulus but greatly increased the Vicker's hardness of resin disks. By continuing to release Ag + ions without the impact of anaerobic environment, resins containing AgBr/BHPVP nanoparticles are particularly suitable to combat anaerobic cariogenic bacteria. By reason of the combined bactericidal effect of the contact-killing cationic polymers and the releasing-killing Ag + ions, AgBr/BHPVP-containing resin disks had potent bactericidal activity against S. mutans. The long-lasting antibacterial activity was also achieved through the sustained release of Ag + ions due to the core-shell structure of the nanocomposites. The results of macrophage cytotoxicity showed that the cell viability of dental resins loading less than 1.0 wt% AgBr/BHPVP was close to that of neat resins. The AgBr/BHPVP-containing dental resin with dual bactericidal capability and long term antimicrobial effect is a promising material aimed at preventing second caries and prolonging the longevity of resin composite restorations.

  13. The occurrence and geochemistry of fluoride in some natural waters of Kenya

    Science.gov (United States)

    Gaciri, S. J.; Davies, T. C.

    1993-03-01

    In recent years the acquisition of considerable additional data on the hydrogeochemical behaviour of fluoride in natural waters of Kenya has been made possible by extensive surface-water and groundwater sampling campaigns as well as by improvements in analytical techniques. Ultimately, the principal source of fluoride relates to emissions from volcanic activity associated with the East African Rift System. Through various intermediate steps, but also directly, fluoride passes into the natural water system and components of the food chain. Ingestion by man is mainly through drinking water and other beverages. River waters in Kenya generally have a fluoride concentration lower than the recommended level (1.3 ppm) for potable water, thus promoting susceptibility to dental caries. Groundwaters and lake waters show considerably higher fluoride contents, resulting in the widespread incidence of fluorosis in areas where groundwater is the major source of drinking water, and lake fish is a regular component of the diet. This paper presents a synthesis of the data so far obtained on the sources and distribution of fluoride in the hydrological system of Kenya, examines the extent of fluorine toxicity and puts forward recommendations to combat or minimise the problem.

  14. Fluoride remediation using floating macrophytes

    Directory of Open Access Journals (Sweden)

    Naba Kumar Mondal

    2014-04-01

    Full Text Available Six aquatic macrophytes, such as Pistia stratiotes, Ceratophyllum demersum, Nymphoides indica, Lemna major, Azolla pinnata,and Eichhornia crassipes were considered for remove fluoride from aqueous solution. Five different concentrations (10, 30, 50, and 100 ppm of fluoride solution were taken in 1 L plastic container. Fixed weight (20 g of macrophytes along with 500 ml fluoride solution was taken in each plastic container for 72 hours observation. Results demonstrated all the macrophytes show highest fluoride removal during 24 h to 48 h, but after 72 h their efficiency reduced drastically. The species N. indica showed better removal efficiency than other experimental macrophytes. In general, pigment measurement data indicated higher concentration at 72 h. However, Pistia sp. showed higher concentration of pigmentation at intermediate time interval (48 h. Higher level of dry weight to fresh weight ratio was recorded for L. major and A. pinnata at all concentrations, excepting at 10 ppm. In addition, all macrophytes showed lower RGR at higher concentration. Isotherm study indicated that macrophyte C. demersum is a good fitted with Freundlich and Langmuir isotherm whereas L. major with Langmuir isotherm during 24 hours.

  15. Long-term effect of intensive prevention on dental health of primary school children by socioeconomic status.

    Science.gov (United States)

    Winter, Julia; Jablonski-Momeni, Anahita; Ladda, Annett; Pieper, Klaus

    2017-12-29

    Children in a German region took part in regular toothbrushing with fluoride gel during their time in primary school after having received a preventive program in kindergarten. The study aimed at determining the dental health of the students as a function of prevention in kindergarten and at school while taking into account their socioeconomic status and other confounders. The subjects were in six groups: groups 1 and 2, intensive prevention in kindergarten with and without fluoride gel at school; groups 3 and 4, basic prevention in kindergarten with and without fluoride gel at school; groups 5 and 6, no organized prevention in kindergarten with and without fluoride gel at school. Two dental examinations were performed for assessing caries experience and calculating caries increment from second grade (7-year-olds) to fourth grade (9-year-olds). A standardized questionnaire was used to record independent variables. To compare caries scores and preventive measures of various subgroups, non-parametric tests and a binary logistic regression analysis were performed. A significant difference was found in the mean decayed, missing, and filled tooth/teeth (DMFT) depending on socioeconomic status (no prevention in kindergarten, fluoride gel at school in children with low SES: DMFT = 0.47 vs. DMFT = 0.18 in children with high SES; p = 0.023). Class-specific differences were no longer visible among children who had taken part in an intensive preventive program combining daily supervised toothbrushing in kindergarten and application of fluoride gel in school. Early prevention, focusing on professionally supported training of toothbrushing in kindergarten and at school, has a positive effect on dental health and is able to reduce class-specific differences in caries distribution. Early training of toothbrushing and fissure sealing of first permanent molars are the most important factors for the dental health of primary school children.

  16. Comparative evaluation of fluoride release from PRG-composites and compomer on application of topical fluoride: An in-vitro study

    Directory of Open Access Journals (Sweden)

    Dhull K

    2009-03-01

    Full Text Available Aims and Objective: To determine the fluoride release from Giomer and Compomer, using different topical fluoride regimes, and to compare the amount of fluoride release from giomer with that of compomer. Materials and Method: Forty-eight specimens of each giomer and compomer were divided into four treatment groups, namely, control group, fluoridated dentifrice (500 ppm once daily group, fluoridated dentifrice (500 ppm twice daily group, fluoridated dentifrice (500 ppm once daily + fluoridated mouthwash (225 ppm group. Each specimen was suspended in demineralizing solution for six hours and remineralizing solution for 18 hours. Fluoride release was measured in both the demineralizing solution and remineralizing solution daily for seven days. Total daily fluoride release for each specimen was calculated by adding the amount released in the demineralizing solution to that released in remineralizing solution. Results and Conclusion: The fluoride release (ppm was found to be more in Giomer when compared to Compomer. The fluoride released from Giomer and Compomer was significantly greater in the acidic demineralizing solution than in the neutral remineralizing solution. It was found that increasing fluoride exposure significantly increased fluoride release from the giomer and compomer. It was found that the fluoride release from the subgroups of giomer and compomer was in the following order: fluoridated dentifrice twice daily > fluoridated dentifrice once daily + fluoridated mouthwash > fluoridated dentifrice once daily > control group. It was found that the giomer showed a greater fluoride uptake than the compomer.

  17. Use of the theoretical domains framework to further understanding of what influences application of fluoride varnish to children's teeth: a national survey of general dental practitioners in Scotland.

    Science.gov (United States)

    Gnich, Wendy; Bonetti, Debbie; Sherriff, Andrea; Sharma, Shilpi; Conway, David I; Macpherson, Lorna M D

    2015-06-01

    Despite recent improvements in the oral health of Scotland's population, the persistence of childhood dental caries underscores a need to reduce the disease burden experienced by children living in Scotland. Application of fluoride varnish (FV) to children's teeth provides an evidence-based approach to achieving this goal. Despite policy, health service targets and professional recommendations supporting application, not all children receive FV in line with guidance. The objective of this study was to use the theoretical domains framework (TDF) to further an understanding of what may influence fluoride varnish application (FVA) in General Dental Practice in Scotland. A postal questionnaire assessing current behaviour (frequency of FVA) and theoretical domains (TDs) was sent to all General Dental Practitioners (GDPs) in Scotland. Correlations and linear regression models were used to examine the association between FVA and the TDs. One thousand and ninety (53.6%) eligible GDPs responded. Respondents reported applying FV more frequently to increased risk and younger children (aged 2-5 years). Higher scores in eight TDs (Knowledge, Social/professional role and identity, Beliefs about consequences, Motivation and goals, Environmental context and resources, Social influences, Emotion and Behavioural regulation) were associated with greater frequency of FVA. Four beliefs in particular appear to be driving GDPs' decision to apply FV (recognizing that FVA is a guideline recommended behaviour (Knowledge), that FVA is perceived as an important part of the GDPs' professional role (Professional role/identity), that FV is something parents want for their children (Social influences) and that FV is something GDPs really wanted to do (Emotion). The findings of this study support the use of the TDF as a tool to understand GDPs application of FV and suggest that a multifaceted intervention, targeting dental professionals and families, and more specifically those domains and items

  18. Special cluster issue on tribocorrosion of dental materials

    Science.gov (United States)

    Mathew, Mathew T.; Stack, Margaret M.

    2013-10-01

    Tribocorrosion affects all walks of life from oil and gas conversion to biomedical materials. Wear can interact with corrosion to enhance it or impede it; conversely, corrosion can enhance or impede wear. The understanding of the interactions between physical and chemical phenomena has been greatly assisted by electrochemical and microscopic techniques. In dentistry, it is well recognized that erosion due to dissolution (a term physicists use to denote wear) of enamel can result in tooth decay; however, the effects of the oral environment, i.e. pH levels, electrochemical potential and any interactions due to the forces involved in chewing are not well understood. This special cluster issue includes investigations on the fundamentals of wear-corrosion interactions involved in simulated oral environments, including candidate dental implant and veneer materials. The issue commences with a fundamental study of titanium implants and this is followed by an analysis of the behaviour of commonly used temporomandibular devices in a synovial fluid-like environment. The analysis of tribocorrosion mechanisms of Ti6Al4V biomedical alloys in artificial saliva with different pHs is addressed and is followed by a paper on fretting wear, on hydroxyapatite-titanium composites in simulated body fluid, supplemented with protein (bovine serum albumin). The effects of acid treatments on tooth enamel, and as a surface engineering technique for dental implants, are investigated in two further contributions. An analysis of the physiological parameters of intraoral wear is addressed; this is followed by a study of candidate dental materials in common beverages such as tea and coffee with varying acidity and viscosity and the use of wear maps to identify the safety zones for prediction of material degradation in such conditions. Hence, the special cluster issue consists of a range of tribocorrosion contributions involving many aspects of dental tribocorrosion, from analysis of physiological

  19. Recomendaciones sobre el uso de fluoruros para prevenir y controlar la caries dental en los Estados Unidos

    Directory of Open Access Journals (Sweden)

    2002-01-01

    Full Text Available The widespread use of fluoride has been fundamental in reducing the prevalence and severity of dental caries in the United States of America and in other developed countries. When used appropriately, fluoride is safe and effective in preventing and controlling dental caries. Today, nearly all the residents of the United States are in some measure exposed to fluoride, which can come from multiple sources. This document is based on a report prepared by a working group assembled by the Centers for Disease Control and Prevention of the United States. The report details recommendations on fluoride use to prevent and control caries in the United States, but some aspects of the report could also be valid for other countries. Frequent exposure to small amounts of fluoride on a daily basis is the best way to reduce the risk of caries in all age groups. Therefore, it is recommended that all people drink water with an optimal fluoride concentration and that they brush their teeth twice a day with a fluoride toothpaste. Individuals with a high risk of caries may need additional fluoride sources. These recommendations attempt to provide dentists and other health professionals, public health professionals, and the general public with guidelines for fluoride use so that there is maximum protection against caries but without increasing the risk of enamel fluorosis, and with an efficient use of available resources. The recommendations are divided into four major groups: 1 public health and clinical practice, 2 self-care or individuals, 3 consumer-product industries and professional health care organizations and public health agencies, and 4 new research. Adopting these recommendations could reduce even further the prevalence of dental caries in the United States and save both public and private resources.

  20. Short term serum pharmacokinetics of diammine silver fluoride after oral application.

    Science.gov (United States)

    Vasquez, Elsa; Zegarra, Graciela; Chirinos, Edgar; Castillo, Jorge L; Taves, Donald R; Watson, Gene E; Dills, Russell; Mancl, Lloyd L; Milgrom, Peter

    2012-12-31

    There is growing interest in the use of diammine silver fluoride (DSF) as a topical agent to treat dentin hypersensitivity and dental caries as gauged by increasing published research from many parts of the world. While DSF has been available in various formulations for many years, most of its pharmacokinetic aspects within the therapeutic concentration range have never been fully characterized. This preliminary study determined the applied doses (3 teeth treated), maximum serum concentrations, and time to maximum serum concentration for fluoride and silver in 6 adults over 4 h. Fluoride was determined using the indirect diffusion method with a fluoride selective electrode, and silver was determined using inductively coupled plasma-mass spectrometry. The mean amount of DSF solution applied to the 3 teeth was 7.57 mg (6.04 μL). Over the 4 hour observation period, the mean maximum serum concentrations were 1.86 μmol/L for fluoride and 206 nmol/L for silver. These maximums were reached 3.0 h and 2.5 h for fluoride and silver, respectively. Fluoride exposure was below the U.S. Environmental Protection Agency (EPA) oral reference dose. Silver exposure exceeded the EPA oral reference dose for cumulative daily exposure over a lifetime, but for occasional use was well below concentrations associated with toxicity. This preliminary study suggests that serum concentrations of fluoride and silver after topical application of DSF should pose little toxicity risk when used in adults. NCT01664871.