Evaluation of the appreciation of virtual teeth with and without pathology.

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de Boer, I R; Lagerweij, M D; Wesselink, P R; Vervoorn, J M

2015-05-01

Virtual teeth with and without tooth pathology have been developed for use in a virtual learning environment in dental education. The objective of this study was to evaluate the appearance of these virtual teeth for use in dental education and to compare them with contemporary educational models, such as plastic teeth (Frasaco GmbH) and extracted human teeth. Six sets of photographs representing six different teeth were shown to dentists, teachers (dentists) and dental students (bachelor's and master's degree students). Each set consisted of 15 pictures showing five views of the extracted human tooth, the similar virtual tooth and the plastic tooth. The five views represented the mesial, distal, occlusal, buccal and lingual surfaces. The virtual tooth was the same as the extracted tooth (scanned with a cone beam CT, coloured and edited in ColorMapEditor(®) ), and the plastic tooth presented the best possible match to the extracted tooth. The participants were asked to rate the appearance of the virtual teeth (overall and in terms of caries, restoration and colours), whether the virtual or plastic teeth resembled the extracted teeth better and from which teeth they expected to learn the most (extracted, virtual or plastic). Each group of participants found that the virtual teeth resembled the extracted teeth more than they resembled the plastic teeth; 71% of the participants expected to learn more from the virtual teeth than from the plastic teeth. The results show that the appearance of the virtual teeth was considered more realistic than the appearance of the plastic teeth. The expectation was that the learning opportunities of the virtual teeth are better than of the plastic teeth. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Criteria adopted by dentists to indicate the extraction of periodontally involved teeth

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Carlos Heitor Cunha Moreira

2007-10-01

Full Text Available When dealing with patients with periodontal disease of variable severities, dentists must often choose between treating and restoring the involved tooth or indicating its extraction. Different criteria have been adopted in this decision-making process. The purpose of this study was to evaluate the criteria adopted by dentists to indicate the extraction of teeth with periodontitis. Dentists were interviewed at their private practices in three cities of the state of Rio Grande do Sul, Brazil. The evaluated criteria included severity of attachment loss, tooth mobility, furcation involvement, prosthetic planning, periodontal-endodontic lesion, possible systemic involvement due to the presence of periodontitis, referral to a periodontist for evaluation, radiographic bone loss greater than 50%, presence of extensive caries, socio-economic and cultural status of the patient, among others. The most often adopted criteria to indicate the extraction of periodontally affected teeth were the presence of mobility (37.5%, severity of attachment loss (24.3% and radiographic bone loss greater than 50% (21.2%. The results of the present study demonstrated the difficulties faced by dentists to indicate the extraction of teeth with severe attachment loss, in addition to the establishment of an adequate prognosis. Aspects associated with the past disease were still the most often reported to indicate the extraction of teeth for periodontal reasons.

Sorption of zinc on human teeth

International Nuclear Information System (INIS)

Helal, A.; Amin, H.; Alian, G.

1997-01-01

Zinc containing dental amalgams are sometimes used as fillings by dentists. The freshly mixed mass of the amalgam alloy and liquid mercury packed or condensed into a prepared tooth cavity. Zinc has been included in amalgams alloys up to 2% as an aid in manufacturing by helping to produce clean sound castings of the ingots. Although such restorations have a relatively long service life, they are subject to corrosion and galvanic action, thus releasing metallic products into the oral environment. The aim of this paper is to investigate the uptake (sorption) of Zinc ionic species on human teeth using the radioactive tracer technique. For this purpose the isotope Zn-65 produced from pile-irradiation of zinc metal was used. The various liquids studied were drinking water (tap water), tea, coffee, red tea and chicken soup. Sorption was studied through immersion of a single human tooth (extracted) in each of these liquids

[Use of "gelatamp" colloidal silver gelatin sponge to prevent dry socket after extracting mandibular impacted teeth].

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Wang, Yao-zhong; Guan, Qun-li; Li, Ya-xin; Guo, Ji-lai; Jiang, Ling; Jia, Mu-yun; Deng, Yue

2013-02-01

To study the clinical effect of "gelatamp" colloidal silver gelatin sponge on preventing dry socket after extracting the mandibular impacted teeth. 1350 teeth extracted from 976 patients who needed to extract the mandibular impacted teeth were divided into group A, group B and group C randomly. "Gelatamp" colloidal silver gelatin sponge was implanted into alveolar socket after teeth extraction in group A, with absorbable gelatin sponge was implanted into alveolar socket in group B and nothing was implanted into alveolar socket in group C. The incidence of dry socket was observed, the data was analyzed using SPSS10.0 software package. The incidence of dry socket was 0.44% in group A, 2% in group B and 4.44% in group C. There was significant difference in the incidence of dry socket between group A and group C(Pcolloidal silver gelatin sponge can prevent the occurrence of dry socket after teeth extraction, which is of wide clinical use.

The identification of proteoglycans and glycosaminoglycans in archaeological human bones and teeth.

Science.gov (United States)

Coulson-Thomas, Yvette M; Coulson-Thomas, Vivien J; Norton, Andrew L; Gesteira, Tarsis F; Cavalheiro, Renan P; Meneghetti, Maria Cecília Z; Martins, João R; Dixon, Ronald A; Nader, Helena B

2015-01-01

Bone tissue is mineralized dense connective tissue consisting mainly of a mineral component (hydroxyapatite) and an organic matrix comprised of collagens, non-collagenous proteins and proteoglycans (PGs). Extracellular matrix proteins and PGs bind tightly to hydroxyapatite which would protect these molecules from the destructive effects of temperature and chemical agents after death. DNA and proteins have been successfully extracted from archaeological skeletons from which valuable information has been obtained; however, to date neither PGs nor glycosaminoglycan (GAG) chains have been studied in archaeological skeletons. PGs and GAGs play a major role in bone morphogenesis, homeostasis and degenerative bone disease. The ability to isolate and characterize PG and GAG content from archaeological skeletons would unveil valuable paleontological information. We therefore optimized methods for the extraction of both PGs and GAGs from archaeological human skeletons. PGs and GAGs were successfully extracted from both archaeological human bones and teeth, and characterized by their electrophoretic mobility in agarose gel, degradation by specific enzymes and HPLC. The GAG populations isolated were chondroitin sulfate (CS) and hyaluronic acid (HA). In addition, a CSPG was detected. The localization of CS, HA, three small leucine rich PGs (biglycan, decorin and fibromodulin) and glypican was analyzed in archaeological human bone slices. Staining patterns were different for juvenile and adult bones, whilst adolescent bones had a similar staining pattern to adult bones. The finding that significant quantities of PGs and GAGs persist in archaeological bones and teeth opens novel venues for the field of Paleontology.

Effective of diode laser on teeth enamel in the teeth whitening treatment

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Klunboot, U.; Arayathanitkul, K.; Chitaree, R.; Emarat, N.

2011-12-01

This research purpose is to investigate the changing of teeth color and to study the surface of teeth after treatment by laser diode at different power densities for tooth whitening treatment. In the experiment, human-extracted teeth samples were divided into 7 groups of 6 teeth each. After that laser diode was irradiated to teeth, which were coated by 38% concentration of hydrogen peroxide, during for 20, 30 and 60 seconds at power densities of 10.9 and 52.1 W/cm2. The results of teeth color change were described by the CIEL*a*b* systems and the damage of teeth surface were investigated by scanning electron microscopy (SEM). The results showed that the power density of the laser diode could affect the whiteness of teeth. The high power density caused more luminous teeth than the low power density did, but on the other hand the high power density also caused damage to the teeth surface. Therefore, the laser diode at the low power densities has high efficiency for tooth whitening treatment and it has a potential for other clinical applications.

Comparative analysis of human and bovine teeth: radiographic density

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Jefferson Luis Oshiro Tanaka

2008-12-01

Full Text Available Since bovine teeth have been used as substitutes for human teeth in in vitro dental studies, the aim of this study was to compare the radiographic density of bovine teeth with that of human teeth to evaluate their usability for radiographic studies. Thirty bovine and twenty human teeth were cut transversally in 1 millimeter-thick slices. The slices were X-rayed using a digital radiographic system and an intraoral X-ray machine at 65 kVp and 7 mA. The exposure time (0.08 s and the target-sensor distance (40 cm were standardized for all the radiographs. The radiographic densities of the enamel, coronal dentin and radicular dentin of each slice were obtained separately using the "histogram" tool of Adobe Photoshop 7.0 software. The mean radiographic densities of the enamel, coronal dentin and radicular dentin were calculated by the arithmetic mean of the slices of each tooth. One-way ANOVA demonstrated statistically significant differences for the densities of bovine and human enamel (p 0.05. Based on the results, the authors concluded that: a the radiographic density of bovine enamel is significantly higher than that of human enamel; b the radiodensity of bovine coronal dentin is statistically lower than the radiodensity of human coronal dentin; bovine radicular dentin is also less radiodense than human radicular dentin, although this difference was not statistically significant; c bovine teeth should be used with care in radiographic in vitro studies.

Standing intraoral extractions of cheek teeth aided by partial crown removal in 165 horses (2010-2016).

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Rice, M K; Henry, T J

2018-01-01

Diseased cheek teeth in horses often require invasive extraction techniques that carry a high rate of complications. Techniques and instrumentation were developed to perform partial crown removal to aid standing intraoral extraction of diseased cheek teeth in horses. To analyse success rates and post-surgical complications in horses undergoing cheek teeth extraction assisted by partial crown removal. Retrospective cohort study. This study included 165 horses with 194 diseased cheek teeth that were extracted orally assisted by partial crown removal between 2010 and 2016. Medical records were analysed, including case details, obtained radiographs, surgical reports and follow-up information. Follow-up information (≥2 months) was obtained for 151 horses (91.5%). There were 95 horses examined post-operatively by the authors and, 16 horses by the referring veterinarian; in 40 horses, post-operative follow up was obtained by informal telephone interviews with the owner. Successful standing intraoral extraction of cheek teeth was obtained in 164/165 horses (99.4%). Twenty-five of these horses (15.2%) required additional intraoral extraction methods to complete the extraction, including minimally invasive transbuccal approach (n = 21) and tooth sectioning (n = 4). There was one (0.6%) horse with intraoral extraction failure that required standing repulsion to complete the extraction. The intraoperative complication of fractured root tips occurred in 11/165 horses (6.7%). Post-operative complications occurred in 6/165 horses (3.6%), including alveolar sequestra (n = 4), mild delay of alveolar healing at 2 months (n = 1), and development of a persistent draining tract secondary to a retained root tip (n = 1). Specialised instrumentation and additional training in the technique are recommended to perform partial crown removal in horses. Horses with cheek teeth extraction by partial crown removal have an excellent prognosis for a positive outcome. The term partial coronectomy

Expression and localization of special AT-rich sequence binding protein 2 in murine molar development and the pulp-dentin complex of human healthy teeth and teeth with pulpitis

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He, Lina; Liu, Huimei; Shi, Lei; Pan, Shuang; Yang, Xu; Zhang, Lin; Niu, Yumei

2017-01-01

Special AT-rich sequence binding protein 2 (SATB2) is a member of the special family of AT-rich binding transcription factors and has a critical role in osteoblast differentiation and craniofacial patterning. However, the expression and distribution of SATB2 in tooth development is largely unknown. The aim of the present study was to detect the expression and distribution of SATB2 during murine molar development and, in human healthy teeth and teeth with pulpitis using immunohistochemistry. Molars were obtained from Kunming mice at embryonic day (E) 13.5, E14.5, E16.5 and E18.5, and postnatal day (P) 1, P5 and P7. In addition, 20 human teeth (10 healthy and 10 teeth with pulpitis) were obtained from young adult patients (age, 24.90±1.65 years) who were scheduled for routine extraction. Immunohistochemical analyses were performed to detect the expression and distribution of SATB2. The present results revealed that SATB2 exhibits a spatiotemporal expression pattern in murine molar development and was expressed in odontoblasts, predentin, dental pulp cells and the blood vessels in human teeth. These findings suggested that SATB2 may have an important role in odontoblast differentiation and dentin matrix mineralization during tooth development. PMID:29042940

The antimicrobial effectiveness of 25% propolis extract in root canal irrigation of primary teeth.

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Verma, Manjesh Kumar; Pandey, Ramesh Kumar; Khanna, Richa; Agarwal, Jyotsna

2014-01-01

The choice of irrigating solution used in root canals of primary teeth is complicated by their complex morphology and paucity of associated literature. Propolis is a natural product that has gained interest in this context due to its antibacterial effectiveness against several endodontic pathogens. The present study was undertaken to assess the potential of water-soluble 25% propolis extract against microorganisms present in root canals of primary teeth during endodontic procedures. The child patients in the age group of 4-7 years with radiographic evidence of carious pulp exposure were included in the study. Definitive selection was done after gaining access into the pulp chamber and root canals of the selected teeth. The clinical and radiographic evidence of pathosis was ruled out for inclusion in the study. The selected teeth were divided into two groups randomly. In Group A 0.9% isotonic saline and in Group B 25% extract water-soluble propolis were used as irrigating solution, respectively. The bacterial samples were collected both pre- and post-irrigation and were transferred for microbial assay. STAISTISTICAL ANALYSIS: Wilcoxon matched signed rank test was used to compare the pre-and post-irrigation bacterial counts. Mann-Whitney test was used to compare the mean change (pre-post) in bacterial colony counts of groups in the study. Antimicrobial effectiveness of 25% water-soluble extract of propolis in the root canals of primary teeth was confirmed in the present study. The reduction in the mean bacterial colony counts of all the isolated bacteria was noticed higher in Group B than Group A. The results of the present study have confirmed that the antibacterial effectiveness of water-soluble extract of propolis in the root canals of primary teeth in vivo. Considering the low toxicity concerns and antibacterial effectiveness, water-soluble extract of 25% propolis can be advocated as a root canal irrigant in endodontic treatment of primary teeth.

The antimicrobial effectiveness of 25% propolis extract in root canal irrigation of primary teeth

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Manjesh Kumar Verma

2014-01-01

Full Text Available Context: The choice of irrigating solution used in root canals of primary teeth is complicated by their complex morphology and paucity of associated literature. Propolis is a natural product that has gained interest in this context due to its antibacterial effectiveness against several endodontic pathogens. Aim: The present study was undertaken to assess the potential of water-soluble 25% propolis extract against microorganisms present in root canals of primary teeth during endodontic procedures. Settings and Design: The child patients in the age group of 4-7 years with radiographic evidence of carious pulp exposure were included in the study. Definitive selection was done after gaining access into the pulp chamber and root canals of the selected teeth. The clinical and radiographic evidence of pathosis was ruled out for inclusion in the study. Materials and Methods: The selected teeth were divided into two groups randomly. In Group A 0.9% isotonic saline and in Group B 25% extract water-soluble propolis were used as irrigating solution, respectively. The bacterial samples were collected both pre- and post-irrigation and were transferred for microbial assay. Staististical Analysis: Wilcoxon matched signed rank test was used to compare the pre-and post-irrigation bacterial counts. Mann-Whitney test was used to compare the mean change (pre-post in bacterial colony counts of groups in the study. Results: Antimicrobial effectiveness of 25% water-soluble extract of propolis in the root canals of primary teeth was confirmed in the present study. The reduction in the mean bacterial colony counts of all the isolated bacteria was noticed higher in Group B than Group A. Conclusion: The results of the present study have confirmed that the antibacterial effectiveness of water-soluble extract of propolis in the root canals of primary teeth in vivo. Considering the low toxicity concerns and antibacterial effectiveness, water-soluble extract of 25% propolis

A comparison of the antibacterial activity of the two methods of photodynamic therapy (using diode laser 810 nm and LED lamp 630 nm) against Enterococcus faecalis in extracted human anterior teeth.

Science.gov (United States)

Asnaashari, Mohammad; Mojahedi, Seyed Masoud; Asadi, Zahra; Azari-Marhabi, Saranaz; Maleki, Alireza

2016-03-01

Failure of endodontic treatment is usually due to an inadequate disinfection of the root canal system. Enterococcus faecalis has been widely used as a valuable microbiological marker for in-vitro studies because of its ability to colonize in a biofilm like style in root canals, invading dentinal tubules and resistance to some endodontic treatments. The aim of this study was to investigate the antibacterial effects of two methods of photodynamic therapy using a light emitting diode lamp (LED lamp, 630 nm) and a diode laser (810 nm) on E. faecalis biofilms in anterior extracted human teeth. Fifty six single-rooted extracted teeth were used in this study. After routine root canal cleansing, shaping and sterilization, the teeth were incubated with E. faecalis for a period of two weeks. Teeth were then divided into two experimental groups (nu=23) and two control groups (nu=5). Teeth in one experimental group were exposed to a diode laser (810 nm), and in the other group samples were exposed to a LED lamp (630 nm). Intracanal bacterial sampling was done, and bacterial survival rate was then evaluated for each group. The Colony Forming Unit (CFU) in LED group (log10 CFUs=4.88±0.82) was significantly lower than the laser group (log CFUs=5.49±0.71) (p value=0.021). CFUs in positive control group (Log10 CFUs=10.96±0.44) were significantly higher than the treatment group (p˂0.001). No bacterial colony was found in negative control group. The results of this research show that photodynamic therapy could be an effective supplement in root canal disinfection. PDT using LED lamp was more effective than diode laser 810 nm in reducing CFUs of E. faecalis in human teeth. Copyright © 2015 Elsevier B.V. All rights reserved.

The identification of proteoglycans and glycosaminoglycans in archaeological human bones and teeth.

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Yvette M Coulson-Thomas

Full Text Available Bone tissue is mineralized dense connective tissue consisting mainly of a mineral component (hydroxyapatite and an organic matrix comprised of collagens, non-collagenous proteins and proteoglycans (PGs. Extracellular matrix proteins and PGs bind tightly to hydroxyapatite which would protect these molecules from the destructive effects of temperature and chemical agents after death. DNA and proteins have been successfully extracted from archaeological skeletons from which valuable information has been obtained; however, to date neither PGs nor glycosaminoglycan (GAG chains have been studied in archaeological skeletons. PGs and GAGs play a major role in bone morphogenesis, homeostasis and degenerative bone disease. The ability to isolate and characterize PG and GAG content from archaeological skeletons would unveil valuable paleontological information. We therefore optimized methods for the extraction of both PGs and GAGs from archaeological human skeletons. PGs and GAGs were successfully extracted from both archaeological human bones and teeth, and characterized by their electrophoretic mobility in agarose gel, degradation by specific enzymes and HPLC. The GAG populations isolated were chondroitin sulfate (CS and hyaluronic acid (HA. In addition, a CSPG was detected. The localization of CS, HA, three small leucine rich PGs (biglycan, decorin and fibromodulin and glypican was analyzed in archaeological human bone slices. Staining patterns were different for juvenile and adult bones, whilst adolescent bones had a similar staining pattern to adult bones. The finding that significant quantities of PGs and GAGs persist in archaeological bones and teeth opens novel venues for the field of Paleontology.

Sorption of antimony on human teeth

International Nuclear Information System (INIS)

Nofal, M.; Amin, H.; Alian, G.

1997-01-01

The study of the uptake of toxic elements on human teeth represents an interesting research area, as the fate of these elements when present in the human food is of health significance. Since antimony is one of the common toxic elements and since, the chemical behaviour of antimony is similar to that of arsenic, one of the most important toxic elements commonly encountered in cases of food poisoning, it has been decided to investigate its uptake on human teeth and on other restoration materials. The radioactive tracer technique was used to evaluate the concentration of antimony sorbed on teeth. This tracer was obtained by irradiation of antimony metal in the reactor, subsequent dissolution in concentrated sulphuric acid, evaporation to dryness and making the solution 6 M in Hydrochloric acid (1). Antimony prepared in this way is in the trivalent state (Sb III). Sorption was studied in water, tea, coffee, red tea and chicken soup. The highest sorption was achieved from water and chicken soup and least sorption was noticed in case of coffee. The results are presented in the form of the depletion of the radioactivity (A) of antimony with time in presence of a tooth in water and other drinks

Reasons for extraction in primary teeth among 5-12 years school children in Haryana, India- A cross-sectional study.

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Bansal, Mohit; Gupta, Nidhi; Gupta, Preety; Arora, Vikram; Thakar, Sahil

2017-04-01

Due to high prevalence of oral diseases extraction of primary teeth is a common and a major concern in developing countries. These teeth are given least importance as they are believed to shed off automatically, thus leading to serious problems like crowding and malocclusion. A cross sectional study was carried out among children aged 5 to 12 years among 1347 children. The data was recorded on a prestructured questionnaire. Reasons for extraction of teeth were based on Kay and Blinkhorn criteria. 20.4% children were having tooth loss due to various reasons. The main reason for extraction was found to be caries in 64.3% followed by trauma in maxillary teeth among 43.02% of children. Presence of early loss of primary teeth result in occlusal disturbances and space loss among children. Hence, proper treatment regimens must be followed by the dental professionals and should be the need of the hour. Key words: Extraction, children, primary teeth, caries.

Extraction of Unerupted Maxillary Canine Teeth in a Maned Wolf (Chrysocyon brachyurus

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Lourdes M. B. Pessoa

2016-01-01

Full Text Available The purpose of this case report is to describe the diagnosis and treatment of unerupted canine teeth in a maned wolf. After physical examination, complete blood count, and serum biochemical profile, the animal underwent general anesthesia and head radiography was performed to confirm the diagnosis. The treatment consisted of the extraction of both maxillary canine teeth and clinical and radiographic follow-up of the right mandibular canine tooth.

Extraction of Unerupted Maxillary Canine Teeth in a Maned Wolf (Chrysocyon brachyurus)

OpenAIRE

Pessoa, Lourdes M. B.; Roza, Marcello; Farias, Anderson; Jesus, Pedro Henrique de; Campbell, Rita de Cassia; Pinho, Mariângela Pereira de

2016-01-01

The purpose of this case report is to describe the diagnosis and treatment of unerupted canine teeth in a maned wolf. After physical examination, complete blood count, and serum biochemical profile, the animal underwent general anesthesia and head radiography was performed to confirm the diagnosis. The treatment consisted of the extraction of both maxillary canine teeth and clinical and radiographic follow-up of the right mandibular canine tooth.

Mercury Amalgam Diffusion in Human Teeth Probed Using Femtosecond LIBS.

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Bello, Liciane Toledo; da Ana, Patricia Aparecida; Santos, Dário; Krug, Francisco José; Zezell, Denise Maria; Vieira, Nilson Dias; Samad, Ricardo Elgul

2017-04-01

In this work the diffusion of mercury and other elements from amalgam tooth restorations through the surrounding dental tissue (dentin) was evaluated using femtosecond laser-induced breakdown spectroscopy (fs-LIBS). To achieve this, seven deciduous and eight permanent extracted human molar teeth with occlusal amalgam restorations were half-sectioned and analyzed using pulses from a femtosecond laser. The measurements were performed from the amalgam restoration along the amalgam/dentin interface to the apical direction. It was possible to observe the presence of metallic elements (silver, mercury, copper and tin) emission lines, as well as dental constituent ones, providing fingerprints of each material and comparable data for checking the consistence of the results. It was also shown that the elements penetration depth values in each tooth are usually similar and consistent, for both deciduous and permanent teeth, indicating that all the metals diffuse into the dentin by the same mechanism. We propose that this diffusion mechanism is mainly through liquid dragging inside the dentin tubules. The mercury diffused further in permanent teeth than in deciduous teeth, probably due to the longer diffusion times due to the age of the restorations. It was possible to conclude that the proposed femtosecond-LIBS system can detect the presence of metals in the dental tissue, among the tooth constituent elements, and map the distribution of endogenous and exogenous chemical elements, with a spatial resolution that can be brought under 100 µm.

Prospective clinical study comparing intraligamentary anesthesia and inferior alveolar nerve block for extraction of posterior mandibular teeth.

Science.gov (United States)

Kämmerer, P W; Adubae, A; Buttchereit, I; Thiem, D G E; Daubländer, M; Frerich, B

2018-04-01

The aim of the study was to compare the efficacy of intraligamentary anesthesia (ILA) with conventional inferior alveolar nerve block (IANB) for extraction of mandibular posterior teeth. In a prospective clinical trial, a total of 301 mandibular posterior teeth were extracted in 266 patients. Randomization was conducted into those who received ILA (patients n = 98; teeth n = 105) and those who received IANB (patient n = 140; teeth n = 140). Twenty-eight patients were subjected to bilateral mandibular dental extractions and received both ILA und IANB (teeth n = 56 (ILA n = 28; IANB n = 28)). The primary objective was to evaluate the differences in pain during injection, in pain during tooth extraction (numeric rating scale (NRS)), and in anesthetic quality (complete/sufficient vs. insufficient/no effect). Differences in latency time, amount of anesthetic solution, need for second injection, and duration of local numbness as well as in the incidence of dry socket were assessed. ILA had significant lower pain of injection (p < 0.001), shorter latency time (p < 0.001), and shorter duration of local numbness (p < 0.001) and required lesser amount of local anesthetic solution (p < 0.001) together with a similar anesthetic quality (p = 0.082) compared to IANB. Concerning pain during extraction (p = 0.211), frequency of second injection (p = 0.197), and incidence of dry socket (p = 0.178), no significant differences were detected. ILA fulfills the requirements of a minimal invasive and patient-friendly local anesthetic technique. In accordance, it represents a safe and reliable alternative to IANB for extraction of mandibular posterior teeth. ILA can be recommended for routine dental extractions.

LOSS OF SPACE ACCORDING TO THE TIME AND THE TYPE OF THE PREMATURE EXTRACTED DECIDUOUS TEETH

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Radosveta S. Andreeva

2016-06-01

Full Text Available There is a difference of space loss depending on the time of premature extraction and the type of the prematurely extracted teeth. The aim of the study is to determine the space loss according to the time and the type of the extracted teeth. Material and methods: We studied 90 children 6 to 9 years old with premature loss of one or more primary teeth divided into three groups according to the severity of the orthodontic deformation. We used two biometric methods – the Moyers method and measured the mesial and distal movement of the adjustment teeth by drawing perpendicular lines towards the middle line. Results: The average amount of space lost is 0,033 mm for the first group, 2,2 for the second and 3,16 for the third group. The lack of space when the first primary molars are extracted is 0,37 mm in the upper jaw and is due to medicalization of the second primary molar. In the lower jaw the loss of space is – 1,12mm. The lack of space when the second primary molars are prematurely extracted is 1,2 for the upper and 1,45 for the lower jaw. Conclusion: The time is a significant factor for the loss of space. The reduction of space increases when the premature extraction is done before more than two months and when second primary molars are extracted.

Prevalence regarding the type of periapical pathology in 102 human teeth extracted with associated periapical lesion

OpenAIRE

Vier, Fabiana Vieira; Figueiredo, José Antônio Poli de

2000-01-01

Objective: The aim of the present study was to verify the prevalence of the cystic and non-cystic lesions, with varied degrees of abscess severity, in teeth bearing periapical lesions associated to the dental apex at the time of their extraction. Material and methods: In order to do so, semi-serial cuts were conducted in 102 periapical lesions which were then dyed by the HE technique. The lesions were classified by two observers in periapical granuloma, 1,2 and 3 degrees periapical abscess, 1...

Correlation between three color coordinates of human teeth

Science.gov (United States)

Lee, Yong-Keun

2014-11-01

The objective was to determine whether there were significant correlations in the three color coordinates within each of two color coordinate systems, such as the Commission Internationale de l'Eclairage (CIE) L*a*b* system, and the lightness, chroma, and hue angle system, of human vital teeth. The color of six maxillary and six mandibular anterior teeth was measured by the Shade Vision System. Pearson correlations between each pair of the color coordinates were determined (α=0.01). The influence of two color coordinates on the other color coordinate was determined with a multiple regression analysis (α=0.01). Based on correlation analyses, all the color coordinate pairs showed significant correlations except for the chroma and hue angle pair. The CIE L* was negatively correlated with the CIE a*, b*, and chroma, but positively correlated with the hue angle. The CIE a* was positively correlated with the CIE b* and chroma. Tooth color coordinates were correlated each other. Lighter teeth were less chromatic both in the CIE a* and b* coordinates. Therefore, it was postulated that the three color coordinates of human teeth were harmonized within certain color attribute ranges, and a lack of correlations in these coordinates might indicate external/internal discolorations and/or anomalies of teeth.

Use of elevator instruments when luxating and extracting teeth in dentistry: clinical techniques.

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Mamoun, John

2017-06-01

In dentistry, elevator instruments are used to luxate teeth, and this technique imparts forces to tooth particles that sever the periodontal ligament around tooth roots inside the socket and expand alveolar bone around tooth particles. These effects can result in extraction of the tooth particles or facilitate systematic forceps extraction of the tooth particles. This article presents basic oral surgery techniques for applying elevators to luxate teeth. Determination of the optimal luxation technique requires understanding of the functions of the straight elevator and the Cryer elevator, the concept of purchase points, how the design elements of elevator working ends and tips influence the functionality of an elevator, application of forces to tooth particles, sectioning teeth at furcations, and bone removal to facilitate luxation. The effectiveness of tooth particle luxation is influenced by elevator tip shape and size, the magnitude and the vectors of forces applied to the tooth particle by the tip, and sectioning and bone removal within the operating field. Controlled extraction procedures are facilitated by a dental operating microscope or the magnification of binocular surgical loupes telescopes, combined with co-axial illumination.

Nature and pattern of primary teeth extractions in a tertiary care hospital setting in South India

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Shini Susan Samuel

2018-01-01

Full Text Available Background: Many studies have been carried out on the prevalence of dental diseases in children although not much information is available regarding its outcome among Indian children. Aim: The aim of the present study was to analyze the type of primary tooth extracted and the reasons for the extraction among children attending a tertiary care hospital in the Southern part of India. Materials and Methods: The dental records of pediatric patients who had visited the dental clinic of a tertiary care hospital located in Tamil Nadu, South India from December 2013 to November 2016 were reviewed. Patients who underwent extraction of at least one primary tooth under local or general anesthesia were included in the study. Results: A total of 943 primary teeth were extracted from 447 patients over 3 years. The most commonly extracted tooth type was the first primary molar followed by the primary central incisor. Grouping by age, the most frequently extracted tooth type between 2 and 5 years was the primary central incisor, the first primary molar among the 6–9-year-old and the second primary molar among 10–15-year-old. The majority of primary teeth extractions were performed in the age group of 6–9 years. No significant gender differences were noted. The most common reason for extraction of primary teeth in children was dental caries. Conclusions: This study demonstrates a high prevalence of untimely primary teeth extractions in young children and dental caries continues to be the leading cause. It clearly reflects on the lack of infant oral health care, the inadequacy of awareness and underutilization of oral health services among children in India.

[Observation of osteoclasts on the root surface during human deciduous teeth resorption].

Science.gov (United States)

Bao, Xiang-jun; Liang, Xing; Chen, Ming; Wang, Hang; Xie, Zhi-gang; Yang, Xiao-yu

2004-08-01

To observe osteoclasts on the resorbing surface of human deciduous teeth. After fixing the collected deciduous teeth, we prepared the tooth slices without decalcification, treated them with HE and TRAP dyestuff, and observed the osteoclasts under light and scanning electron microscope. There were large quantity of various forms of overlapping and huge osteoclasts with many nuclei and silk-like protuberances on the resorbing surface of deciduous teeth. The multinucleated osteoclasts align on the surface of coarse dentin. On the resorbing surface of human deciduous teeth there are large amount of osteoclasts which can be used as a source of studying human osteoclast.

Clinical Analysis of Analgesics and Steroids Use for Extraction of Teeth in Patients with Intellectual Disability Under General Anesthesia.

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Maeda, Shigeru; Honda, Yuka; Tanimura, Hiroshi; Tomoyasu, Yumiko; Higuchi, Hitoshi; Murata, Naomichi; Egusa, Masahiko; Miyawaki, Takuya

2017-01-01

The extraction of lower wisdom teeth is often performed under general anesthesia in patients with intellectual disabilities. However, the choice of analgesics has not yet been investigated. To analyze the use of analgesics during general anesthesia for extraction including lower wisdom teeth in patients with intellectual disabilities. This research is a retrospective observational study. The study population was composed of all patients presenting for extraction of lower wisdom teeth under ambulatory general anesthesia in the clinic of Special Needs Dentistry in Okayama University Hospital from April 2011 to March 2016. The distribution of the combination of analgesics and the relationship between the use of analgesics and the type of extraction were investigated. One hundred and twelve cases were enrolled in this study. Intravenous injections of flurbiprofen, acetaminophen and betamethasone were used in 96 (85.7%), 12 (10.7%) and 26 cases (23.2%), respectively. Flurbiprofen is a non-steroid anti-inflammatory drugs (NSAIDs). Acetaminophen is an old analgesic, but an injection of acetaminophen is new, which was released in 2013 in Japan. And betamethasone is not an analgesic, but a steroid. Betamethasone was used in combination with other analgesics, and was used at a higher dose in a case in which four wisdom teeth were extracted. Flurbiprofen was the main analgesic used for extraction of wisdom teeth under general anesthesia in patients with intellectual disabilities. Betamethasone was used to support flurbiprofen or acetaminophen for extractions of multiple wisdom teeth, with the aim of controlling swelling rather than relieving pain.

Fluorescence properties of human teeth and dental calculus for clinical applications

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Lee, Yong-Keun

2015-04-01

Fluorescent emission of human teeth and dental calculus is important for the esthetic rehabilitation of teeth, diagnosis of dental caries, and detection of dental calculus. The purposes of this review were to summarize the fluorescence and phosphorescence of human teeth by ambient ultraviolet (UV) light, to investigate the clinically relevant fluorescence measurement methods in dentistry, and to review the fluorescence of teeth and dental calculus by specific wavelength light. Dentine was three times more phosphorescent than enamel. When exposed to light sources containing UV components, the fluorescence of human teeth gives them the quality of vitality, and fluorescent emission with a peak of 440 nm is observed. Esthetic restorative materials should have fluorescence properties similar to those of natural teeth. Based on the fluorescence of teeth and restorative materials as determined with a spectrophotometer, a fluorescence parameter was defined. As to the fluorescence spectra by a specific wavelength, varied wavelengths were investigated for clinical applications, and several methods for the diagnosis of dental caries and the detection of dental calculus were developed. Since fluorescent properties of dental hard tissues have been used and would be expanded in diverse fields of clinical practice, these properties should be investigated further, embracing newly developed optical techniques.

Human teeth with periapical pathosis after overinstrumentation and overfilling of the root canals: a scanning electron microscopic study.

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Gutiérrez, J H; Brizuela, C; Villota, E

1999-01-01

The aim of this study was to determine whether overinstrumentation followed by immediate overfilling could be a potential risk in the treatment of infected root canals. Thirty-five human teeth with infected root canals were overinstrumented and overfilled approximately 45 min after their extraction. The experimental teeth were enlarged up to size 40 and the overinstrumentation and overfilling were checked with the aid of a magnifying glass. The specimens were fixed in glutaraldehyde plus sodium cacodylate solution and prepared for scanning electron microscope examination. Bacteria were detected on the flute of the files and mostly at the root apices around the main foramen, remaining firmly attached to resorptive lacunae despite the fact that the apices had undergone great changes, including fracture or zipping. A control group consisting of 10 human teeth root canals containing vital pulps were also overinstrumented and overfilled. No bacteria were detected on the flutes of the files, at the apices or on the extruded master cone overfilling these samples. The high percentage of bacteria adhering to the resorptive lacunae or in the flutes of files used in overinstrumented human teeth with infected root canals carry a potential risk for postoperative pain, clinical discomfort and flare-ups. The hazards observed in these circumstances do not support the one-visit treatment of teeth having acute or chronic periapical abscesses.

A Histopathologic Study on Pulp Response to Glass Ionomer Cements in Human Teeth

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M. Ghavamnasiri

2005-12-01

Full Text Available Statement of Problem: Despite the wide range of new dental materials, there is still a need for biomaterials demonstrating high biocompatibility, antimicrobial effects and ideal mechanical properties.Purpose: The aim of this study was to histologically evaluate the pulpal response to a conventional glass ionomer, a resin modified glass ionomer and a calcium hydroxide in human teeth.Materials and Methods: Fifty five deep class V cavities were prepared in premolars of 31 patients and were divided into 3 groups based on application of the following liners:resin modified glass ionomer (Vivaglass Liner, conventional glass ionomer (ChembondSuperior and calcium hydroxide (Dycal. After applying varnish, teeth were filled with amalgam. Each group was further divided into three subgroups according to time intervals of 7, 30 and 60 days. Teeth were then extracted and their crowns were fixed in formalin. Each sample was assessed microscopically for odontoblastic changes,inflammatory cell infiltration, reactionary dentin formation, remaining dentinal thickness and presence of microorganisms. Statistical analysis including Kruskal Wallis and Mann Whitney was carried out for comparison of mean ranks. (P=0.05.Results: In the Vivaglass Liner group, pulpal response was significantly higher on day 7 as compared to days 30 and 60 (P0.05. There was no correlation between pulpal responses with micro-organisms and remaining dentin thickness (P>0.05.Conclusion: According to the results of this study, light-cured glass ionomer as well as the other tested lining materials were determined to be biologically compatible with vital pulps in deep cavities of sound human teeth.

Standardized method to produce tetracycline-stained human molar teeth in vitro.

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Chan, Daniel C N; Rozier, Gregory Shayne; Steen, Angela; Browning, William D; Mozaffari, Mahmood S

2006-09-01

This study tested the hypothesis that exposure of human molar teeth to tetracycline (TCN) derivatives in vitro results in tooth discoloration resembling the clinical presentation of TCN staining. The effects of exposure of 20 extracted human molar teeth to distilled water, chlortetracycline, doxycycline, or minocycline were compared. The baseline color of each tooth was analyzed with a dental spectrophotometer. The pulp chambers were each filled with a TCN derivative solution and then sealed. The teeth were placed in a centrifuge tube and then centrifuged at 2800 rpm for 20 minutes. Color change was monitored weekly for 7 weeks. Digital images of the surfaces were recorded. For each specimen at every evaluation period, color change from baseline was calculated using Commission Internationale d'Eclairage (CIE) Delta E 2000 (deltae00). There was a significant association between the type of derivative used and deltae00, as well as between the evaluation period and deltae00. There was also a significant association between the interaction term, derivative x evaluation period, and deltae00. Results of the Holm-Sidak post hoc test demonstrated that all 3 TCN derivatives were associated with significantly larger deltae00 than the control group (P < or = .05). All 3 TCN derivative solutions produced significant color changes as time progressed. Different TCN derivatives produced a different L* (lightness), C* (chroma), and H* (hue), with minocycline behaving distinctly differently from chlortetracycline and doxycycline. The model could be used to study the underlying mechanisms of TCN staining as well as many aspects of vital tooth

Forensic DNA typing from teeth using demineralized root tips.

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Corrêa, Heitor Simões Dutra; Pedro, Fabio Luis Miranda; Volpato, Luiz Evaristo Ricci; Pereira, Thiago Machado; Siebert Filho, Gilberto; Borges, Álvaro Henrique

2017-11-01

Teeth are widely used samples in forensic human genetic identification due to their persistence and practical sampling and processing. Their processing, however, has changed very little in the last 20 years, usually including powdering or pulverization of the tooth. The objective of this study was to present demineralized root tips as DNA sources while, at the same time, not involving powdering the samples or expensive equipment for teeth processing. One to five teeth from each of 20 unidentified human bodies recovered from midwest Brazil were analyzed. Whole teeth were demineralized in EDTA solution with daily solution change. After a maximum of approximately seven days, the final millimeters of the root tip was excised. This portion of the sample was used for DNA extraction through a conventional organic protocol. DNA quantification and STR amplification were performed using commercial kits followed by capillary electrophoresis on 3130 or 3500 genetic analyzers. For 60% of the unidentified bodies (12 of 20), a full genetic profile was obtained from the extraction of the first root tip. By the end of the analyses, full genetic profiles were obtained for 85% of the individuals studied, of which 80% were positively identified. This alternative low-tech approach for postmortem teeth processing is capable of extracting DNA in sufficient quantity and quality for forensic casework, showing that root tips are viable nuclear DNA sources even after demineralization. Copyright © 2017 Elsevier B.V. All rights reserved.

[Heat-induced symptomatology in human teeth. An in-vitro study].

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Baldissara, P; Bortolini, S; Papale, G; Scotti, R

1998-09-01

Various dental procedures can generate thermal increase in the dental pulp, in particular if they are incorrectly conducted. In literature the pulp cells are considered very heat sensitive. In this study the symptomatological response of patients during and after thermal administration to the dental crown has been recorded. The analysis of the symptomatology was used as an indication for the definition of the threshold of thermal damage. Twelve healthy teeth of four patients programmed for extraction were subdivided into six couples of homologous teeth. One tooth out of each couple was used for the immediate in vivo recording of the symptoms; the other, once extracted, was used to determine the thermal increase applied through the insertion of a thermocouple sensor. In each couple of teeth the thermal stimulus was equal. The average thermal increase was 11.2 degrees C. Pain starts at temperatures ranging from 39.5 to 50.4 degrees C with an average of 44.6 degrees C. This agrees with classical physiological data which reports the threshold of pain at 45 degrees C. The threshold of pain registered suggests that at temperatures below 44.6 degrees C damage to the dental pulp is improbable, at least in healthy teeth. The limit of 45 degrees C appears, therefore, to be a probable safe threshold, contrary to what is reported in literature.

Survival of Implants in Immediate Extraction Sockets of Anterior Teeth: Early Clinical Results.

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Sabir, Mohammad; Alam, Mohammad Nazish

2015-06-01

The aims and objectives of this study were placement of implants in freshly extracted sockets of anterior teeth and to evaluate the implant stability, peri-implant radiolucency and gingival inflammation around implant over a short period of 30 months. A total of 12 patients (8 male and 4 female), ranging in the age from 20 to 50 years, from March 2007 to June 2007, were evaluated for immediate implant placement into 22 fresh extraction sockets. Only maxillary and mandibular anterior teeth/roots (central incisors, lateral incisors and canines) were considered for replacement with implants. One piece implant with integrated abutment and integrated surface, non-submerged, threaded and tapered at apical 5 mm, sand-blasted and acid etched surfaced implants (HI-TEC TRX-OP Implants of Life Care Company) were used. The mobility was not present in any of the implants at all the follow up visits. There were 2 implants at 6 month, 1 implant at 12 month, 1 implant at 18 month visits, showing peri-implant radiolucency at some sites at bone to implant contact site. Severe gingival inflammation was not observed in any of the implant site. At every follow-up visit, every implant met the criteria of success and none was found to be failed over a 30 months duration i.e. 100% success rate was achieved by implants in immediate extraction socket. The success rate of implant survival in this study was found 100%. These implants have fulfilled all the criteria of implant success and based on the defined criteria, the success rate of implants placed in immediate extraction sockets of anterior teeth compared favorably with the conventional implants. The early results of the present study showed that high survival rates with the implants in immediate extraction sockets can be achieved.

Biophysical dose measurement using electron paramagnetic resonance in rodent teeth

International Nuclear Information System (INIS)

Khan, R.F.H.; Rink, W.J.; Boreham, D.R.

2003-01-01

Electron paramagnetic resonance (EPR) dosimetry of human tooth enamel has been widely used in measuring radiation doses in various scenarios. However, there are situations that do not involve a human victim (e.g. tests for suspected environmental overexposures, measurements of doses to experimental animals in radiation biology research, or chronology of archaeological deposits). For such cases we have developed an EPR dosimetry technique making use of enamel of teeth extracted from mice. Tooth enamel from both previously irradiated and unirradiated mice was extracted and cleaned by processing in supersaturated KOH aqueous solution. Teeth from mice with no previous irradiation history exhibited a linear EPR response to the dose in the range from 0.8 to 5.5 Gy. The EPR dose reconstruction for a preliminarily irradiated batch resulted in the radiation dose of (1.4±0.2) Gy, which was in a good agreement with the estimated exposure of the teeth. The sensitivity of the EPR response of mouse enamel to gamma radiation was found to be half of that of human tooth enamel. The dosimetric EPR signal of mouse enamel is stable up at least to 42 days after exposure to radiation. Dose reconstruction was only possible with the enamel extracted from molars and premolars and could not be performed with incisors. Electron micrographs showed structural variations in the incisor enamel, possibly explaining the large interfering signal in the non-molar teeth

Orthodontic Management with Traction and Asymmetric Extraction for Multiple Impacted Permanent Maxillary Teeth - A Case Report.

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Niu, Qiannan; Zhang, Liang; Dai, Juan; Li, Feifei; Feng, Xue

2016-01-01

Multiple impacted teeth are a rare eruption disturbance that increases the case complexity. In this article, we described a 13-year-old boy whose 5 permanent maxillary teeth were not erupted although their root formation was complete. The orthodontic treatment with traction and asymmetric extraction was performed to achieve a significantly improved functional and esthetic result.

Isolation of Mesenchymal Stem Cells from Human Deciduous Teeth Pulp

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Aileen I. Tsai

2017-01-01

Full Text Available This study aimed to identify predictors of success rate of mesenchymal stem cell (MSC isolation from human deciduous teeth pulp. A total of 161 deciduous teeth were extracted at the dental clinic of Chang Gung Memorial Hospital. The MSCs were isolated from dental pulps using a standard protocol. In total, 128 colonies of MSCs were obtained and the success rate was 79.5%. Compared to teeth not yielding MSCs successfully, those successfully yielding MSCs were found to have less severe dental caries (no/mild-to-moderate/severe: 63.3/24.2/12.5% versus 12.5/42.4/42.4%, P<0.001 and less frequent pulpitis (no/yes: 95.3/4.7% versus 51.5/48.5%, P<0.001. In a multivariate regression model, it was confirmed that the absence of dental caries (OR = 4.741, 95% CI = 1.564–14.371, P=0.006 and pulpitis (OR = 9.111, 95% CI = 2.921–28.420, P<0.001 was significant determinants of the successful procurement of MSCs. MSCs derived from pulps with pulpitis expressed longer colony doubling time than pulps without pulpitis. Furthermore, there were higher expressions of proinflammatory cytokines, interleukin- (IL- 6 and monocyte chemoattractant protein- (MCP- 1, P<0.01, and innate immune response [toll-like receptor 1 (TLR1 and TLR8, P<0.05; TLR2, TLR3, and TLR6, P<0.01] in the inflamed than noninflamed pulps. Therefore, a carious deciduous tooth or tooth with pulpitis was relatively unsuitable for MSC processing and isolation.

Factors influencing treatment decision-making for maintaining or extracting compromised teeth.

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Lang-Hua, Bich Hue; McGrath, Colman P J; Lo, Edward C M; Lang, Niklaus P

2014-01-01

To evaluate treatment decision-making with respect to maintaining periodontally compromised teeth among dentists with or without postgraduate qualifications in implant dentistry. A series of patient scenarios with varying degrees of periodontal disease levels was presented to dental practitioners. Practitioners' decision-making outcome was determined, and intention to retain the compromised teeth was analyzed in bivariate and regression analyses (accounting for postgraduate implant training, gender, years in dental practice, and implant placement experience). This study involved 30 dental practitioners with postgraduate implant qualifications (GDPP), 33 dental practitioners without postgraduate implant qualifications (GDP), and 27 practitioners undergoing training for postgraduate implant qualifications (GDPT). Variations in treatment decision-making were evident between the three groups. Differences in treatment approaches to retaining compromised teeth were apparent. Furthermore, variations in rehabilitation of extracted scenarios existed in terms of use of implant and number of implants need for rehabilitation. Accounting for dentist and practice factors in regression analyses, GDPP/GDPT were three times as likely to retain periodontally compromised upper molar, with or without pain, compared to GDP (without pain OR 3.10, 95%CI 1.04, 10.62 P = 0.04; with pain OR 3.08, 95%CI 1.09, 8.14 P = 0.03). Variations in treatment decision-making with respect to retaining periodontally compromised teeth exist between dental practitioners with and those without postgraduate training in implant dentistry. Furthermore differences in management approaches in how they would retain the teeth or rehabilitate the dental arch were apparent. © 2013 John Wiley & Sons A/S. Published by Blackwell Publishing Ltd.

Opalescence of human teeth and dental esthetic restorative materials.

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Lee, Yong-Keun

2016-12-01

Human tooth enamel is opalescent, which renders teeth bluish in reflected and orange in transmitted color. The aim was to review opalescent property of teeth and application and mimetic reproduction in esthetic restorations. A PubMed search for articles published in English till 2015 on the opalescence of teeth and esthetic materials revealed 29 relevant papers. Opalescence was measured with OP-RT index, which was calculated as the difference in the yellow-blue and red-green color coordinates between the reflected and transmitted colors. Mean OP-RT value of human enamel was 22.9. OP-RT values of direct resin composites changed after polymerization, and the range in these materials was 5.7-23.7. OP-RT value ranges were 1.6-6.1 and 2.0-7.1 for the core and veneer ceramics, respectively. Since the OP-RT values of esthetic materials were lower than that of enamel, it is recommended that materials that can reproduce the opalescence of enamel be further designed.

Mapping the structure, composition and mechanical properties of human teeth

International Nuclear Information System (INIS)

Low, I.M.; Duraman, N.; Mahmood, U.

2008-01-01

The structure-property relationship in human adult and baby teeth was characterised by grazing-incidence synchrotron radiation diffraction, optical and atomic-force microscopy, in addition to Vickers indentation. Similarities and differences between both types of teeth have been highlighted and discussed. Depth-profiling results indicated the existence of contrasting but distinct gradual changes in crystal disorder, phase abundance, crystallite size and hardness within the baby and adult enamel, thus confirming the graded nature of human teeth. When compared to the adult tooth, the baby enamel is softer, more prone to fracture, but has larger hydroxyapatite grains. Vickers hardness of the enamel was load-dependent but load-independent in the dentine. The use of a 'bonded-interface' technique revealed the nature and evolution of deformation-microfracture damage around and beneath Vickers contacts

Mapping the structure, composition and mechanical properties of human teeth

Energy Technology Data Exchange (ETDEWEB)

Low, I.M. [Materials Research Group, Department of Applied Physics, Curtin University of Technology, Perth, WA 6845 (Australia)], E-mail: j.low@curtin.edu.au; Duraman, N.; Mahmood, U. [Materials Research Group, Department of Applied Physics, Curtin University of Technology, Perth, WA 6845 (Australia)

2008-03-10

The structure-property relationship in human adult and baby teeth was characterised by grazing-incidence synchrotron radiation diffraction, optical and atomic-force microscopy, in addition to Vickers indentation. Similarities and differences between both types of teeth have been highlighted and discussed. Depth-profiling results indicated the existence of contrasting but distinct gradual changes in crystal disorder, phase abundance, crystallite size and hardness within the baby and adult enamel, thus confirming the graded nature of human teeth. When compared to the adult tooth, the baby enamel is softer, more prone to fracture, but has larger hydroxyapatite grains. Vickers hardness of the enamel was load-dependent but load-independent in the dentine. The use of a 'bonded-interface' technique revealed the nature and evolution of deformation-microfracture damage around and beneath Vickers contacts.

Culture of human dental pulp cells at variable times post-tooth extraction

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BENÍCIO Daniela Ferreira Araújo

2018-02-01

Full Text Available Abstract The aim of this study was to investigate the viability of human dental pulp cells from extracted teeth kept at standard room temperature and atmospheric pressure for different periods of time. Twenty-one healthy permanent teeth were used. They were divided into five groups according to the expected time from extraction to processing. One group was tested immediately after extraction; the other groups were each tested at one of the following time points: 30 minutes, 1 hour, 2 hours, and 5 hours post-extraction. Cell morphology was analysed by light microscopy; cell proliferation was analysed using MTT assay and by counting the viable cells in a haemocytometer. Similar results were observed in all groups (p < 0.05. A delay of up to five hours for tooth processing and tissue collection does not preclude the establishment of dental pulp cell cultures, affect the morphology of these cells, or reduce their proliferative potential.

Shear bond strength and fracture analysis of human vs. bovine teeth.

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Stefan Rüttermann

Full Text Available PURPOSE: To evaluate if bovine enamel and dentin are appropriate substitutes for the respective human hard tooth tissues to test shear bond strength (SBS and fracture analysis. MATERIALS AND METHODS: 80 sound and caries-free human erupted third molars and 80 freshly extracted bovine permanent central incisors (10 specimens for each group were used to investigate enamel and dentine adhesion of one 2-step self-etch (SE and one 3-step etch and rinse (E&R product. To test SBS the buccal or labial areas were ground plane to obtain appropriate enamel or dentine areas. SE and E&R were applied and SBS was measured prior to and after 500 thermocycles between +5 and +55°C. Fracture analysis was performed for all debonded areas. RESULTS: ANOVA revealed significant differences of enamel and dentin SBS prior to and after thermocycling for both of the adhesives. SBS- of E&R-bonded human enamel increased after thermocycling but SE-bonded did not. Bovine enamel SE-bonded showed higher SBS after TC but E&R-bonded had lower SBS. No differences were found for human dentin SE- or E&R-bonded prior to or after thermocycling but bovine dentin SE-bonded increased whereas bovine dentine E&R-bonded decreased. Considering the totalized and adhesive failures, fracture analysis did not show significances between the adhesives or the respective tooth tissues prior to or after thermocycling. CONCLUSION: Although SBS was different on human and bovine teeth, no differences were found for fracture analysis. This indicates that solely conducted SBS on bovine substrate are not sufficient to judge the perfomance of adhesives, thus bovine teeth are questionnable as a substrate for shear bond testing.

Comparison of different techniques for disinfection of teeth internal space in preclinical teaching

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Tabrizizadeh M.

2009-12-01

Full Text Available "nBackground and Aim: Extracted teeth used in preclinic should be disinfected. The aim of this study was to evaluate the effects of some disinfectants on microorganisms cultured from pulp chamber of extracted teeth."nMaterials and Methods: In this experimental study 54 intact human teeth were collected. After access cavity preparation, 10 8 B. streothermophillus endospors were inoculated into pulp chamber. Then cavities were sealed with a temporary restorative material. Teeth were divided into 5 groups of 10 each. The teeth were then stored in these disinfectants: 5.25% hypochlorite sodium, 5% Microten, 5% Deconex, 2% Glutaraldehyd, and 10% Formalin for 48 hours. Two teeth were autoclaved as negative controls and two were stored in normal saline as positive controls. The teeth were then sectioned in cervical area and cultured in Trypticase Soy Broth. After three days turbidity in tubes was evaluated. Statistical analysis was done by Fisher's exact test."nResults: None of these solutions were able to prevent microorganism growth in all samples; however, Formalin was better in six cases than that of other disinfectants. Differences between these five groups were not statistically significant (P=0.384."nConclusion: Sterilization of the teeth with autoclave is the only absolute method for disinfecting the root canals of extracted teeth and disinfectants are not reliable for this purpose.

On The Evolution of Human Jaws and Teeth: A Review

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Serhat Yalcin

2011-06-01

Full Text Available The jaws and teeth of Homo sapiens have evolved, from the last common ancestor of chimpanzee and men to their current form. Many factors such as the foods eaten and the processing of foods by fire and tools have effected this evolution course. The evolution of the masticatory complex is related to other anatomical features such as brain size and bipedal posture, and leads to important proceedings like the formation of speech and language. In this review, the evolution of human jaws and teeth and its impact on the general course of human evolution is discussed.

Angle Class II malocclusion treated with extraction of permanent teeth

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Gustavo Mattos Barreto

2013-08-01

Full Text Available Angle Class II malocclusion associated with anterior open bite in adult patients demands a carefully elaborated orthodontic planning, aiming at restoring not only harmonious dental and facial esthetics, but also a balanced masticatory function. Orthognathic surgery or permanent teeth extraction are often the choice of treatment, therefore, treatment decision is related to all dental, skeletal and functional aspects. The present report discusses orthodontic compensation carried out by means of upper premolar extraction performed to correct the Class II canine relationship and, consequently, the anterior open bite, accepting that the upper incisors be retroclined. This clinical case was presented to the Brazilian Board of Orthodontics and Dentofacial Orthopedics (BBO as part of the requirements for obtaining the BBO Certification.

Autoradiographic pattern of the in vitro uptake of proline by the coronal areas of intact and carious human teeth

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Karjalainen, S; Soederling, E [Turku Univ. (Finland)

1979-01-01

The biosynthesis of collagen in teeth was studied by following the uptake of proline in vitro. Whole crowns of human teeth were incubated for 6 h with (/sup 14/C)- or (/sup 3/H)-proline. Autoradiographs were prepared from sections of intact teeth and teeth with carious lesions of varying depths and location. The number of silver grains per cm/sup 2/ in the predentine, odontoblast layer and pulp were counted in selected fields magnified x 430 representing the deepest parts of the carious lesions. No differences in the labelling pattern were observed between the intact teeth incubated freshly after extraction and those preserved in liquid nitrogen. The densest labelling of intact teeth was seen in the predentine and odontoblast layer. The alterations under initial dentine caries appeared as increased labelling of the predentine and decreased labelling of the odontoblast layer; no alterations were observed in the underlying pulp. In advanced lesions, the predentine labelling decreased and that in the odontoblast layer and pulp increased. In the initial stages, caries seem to activate collagen synthesis in a relatively restricted area of the underlying structures, but in advanced stages, caries seem to increase the odontoblastic cellular polypeptide chain formation but prevent further maturation of the collagen.

Teeth Caries Decay in MR Imaging

International Nuclear Information System (INIS)

Tanasiewicz, M.M.; Kupka, T.W.; Weglarz, W.P.; Jasinski, A.

2005-01-01

X-ray based visualization techniques were for many years the only way to asses structure and state of the human teeth. MRI has been used in the research of the healthy and decayed teeth during last decade. Several papers were presented showing usefulness of spin echo and gradient echo imaging, Single Point Imaging, SPRITE and STRAFI techniques for visualization of the dental surface geometry as well as for distinction between soft tissue (pulp) and mineralized tissue (enamel, dentine and root cement) in the extracted teeth. Recently, MRI was used for estimation of the facial bone structure, in preparation to implantation, localization of the tumor in the facial bone tissue, and in detection of the osteoporosis. The aim of this work was to investigate potential of MRI for detection and estimation of the caries, on the level of laboratory pre-clinical tests. This work was done within the project to develop original, MRI based diagnostic technique for dentistry needs. MRI experiments were performed on the 5 decayed extracted human teeth (impossible conservative therapy), obtained at Dept. of Dental Surgery MUS. After extraction teeth were stored in saline. MRI measurements were done in MR Tomography Lab INP. Prior to the experiment, tooth was degassed to minimize magnetic susceptibility artifacts. A 3D spin echo pulse sequence on the 4.7 T research MRI system, equipped with Maran DRX console, and dedicated home-built probe head, was used to obtain three dimensional (256x128x128) images of the teeth. Corresponding resolution was 60x120x160 mm 3 . High intensity signal from water penetrated into the porous decayed regions of tooth, contrasted with lack of signal from mineralized tooth tissue, allow for visualization of the presence and extent of caries. Among the 5 measured teeth, MRI allows for detection of the caries in two most decayed tooth. High intensity signal from water penetrated into the porous decayed regions of tooth, contrasted with lack of signal from

Erosive effects of common beverages on extracted premolar teeth.

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Seow, W K; Thong, K M

2005-09-01

Dental erosion is highly prevalent today, and acidic drinks are thought to be an important cause. The aim of the present investigation was to determine the erosive potential of a range of common beverages on extracted human teeth. The beverages were tested for their individual pHs using a pH meter. The clinical effects of the most erosive beverages were determined by the degree of etching and Vickers microhardness of enamel. The results showed that many common beverages have pHs sufficiently low to cause enamel erosion. Lime juice concentrate (pH 2.1) had the lowest pH, followed by Coca-cola and Pepsi (both with pH 2.3) and Lucozade (pH 2.5). The erosive potential of these beverages was demonstrated by the deep etching of the enamel after five minutes. The Vickers Hardness of enamel was reduced by about 50 per cent in the case of lime juice (p case of Coca-cola (p Coca-cola completely reversed the erosive effects on the enamel. Although only a few of the beverages with the lowest pHs were tested, the present study showed that the most acidic drinks had the greatest erosive effects on enamel. While saliva was protective against erosion, relatively large volumes were required to neutralize the acidity.

Trace elements in human, cattle and swine teeth, measured by external beam PIXE-PIGE setup

International Nuclear Information System (INIS)

Tabacniks, M.H.; Rizzutto, M.A.; Added, N.; Liguori Neto, R.; Acquadro, J.C.; Vilela, M.; Oliveira, T.R.C.F.; Markarian, R.A.; Mori, M.

2001-01-01

The use of animal teeth to replace human teeth in dentistry school classes and to test chemicals and fillings, motivated for a better characterization of the elementary composition of their enamel, since some of the chemical properties, adhesion and chemical compatibility may depend on these parameters. Cattle, swine and human teeth were collected by dentists of the University of Sao Paulo. These teeth came primarily from Sao Paulo region and were analyzed for trace elements at the Open Nuclear Physics Laboratory, using a high energy external proton beam, PIXE-PIGE setup

The autoradiographic pattern of the in vitro uptake of proline by the coronal areas of intact and carious human teeth

International Nuclear Information System (INIS)

Karjalainen, S.; Soederling, E.

1979-01-01

The biosynthesis of collagen in teeth was studied by following the uptake of proline in vitro. Whole crowns of human teeth were incubated for 6 h with ( 14 C)- or ( 3 H)-proline. Autoradiographs were prepared from sections of intact teeth and teeth with carious lesions of varying depths and location. The number of silver grains per cm 2 in the predentine, odontoblast layer and pulp were counted in selected fields magnified x 430 representing the deepest parts of the carious lesions. No differences in the labelling pattern were observed between the intact teeth incubated freshly after extraction and those preserved in liquid nitrogen. The densest labelling of intact teeth was seen in the predentine and odontoblast layer. The alterations under initial dentine caries appeared as increased labelling of the predentine and decreased labelling of the odontoblast layer; no alterations were observed in the underlying pulp. In advanced lesions, the predentine labelling decreased and that in the odontoblast layer and pulp increased. In the initial stages, caries seem to activate collagen synthesis in a relatively restricted area of the underlying structures, but in advanced stages, caries seem to increase the odontoblastic cellular polypeptide chain formation but prevent further maturation of the collagen. (author)

Surgical extraction of impacted teeth in elderly patients. A retrospective analysis of perioperative complications - the experience of a single institution.

Science.gov (United States)

Trybek, Grzegorz; Chruściel-Nogalska, Małgorzata; Machnio, Małgorzata; Smektała, Tomasz; Malinowski, Jerzy; Tutak, Marcin; Sporniak-Tutak, Katarzyna

2016-09-01

The aim of this retrospective study was to investigate the most frequent complications and assess their overall rate associated with the surgical extraction of impacted teeth in an elderly patient population. Oral health needs of the elders are often associated with surgical procedures for the creation of appropriate conditions for any further prosthetic treatment. One such process is the removal of severely decayed, fractured or impacted teeth detrimental to the fit or appearance of dentures. While broken and decayed teeth leave little doubt for their removal, impacted teeth divide opinion, some extreme regarding their prophylactic removal and the appropriate age for the procedure. Material was selected from the archives of an Out-Patient Dental Surgery Clinic of the Regional Centre of Dentistry in Szczecin, from 2002 to 2013. The database was independently screened by two investigators according to inclusion and exclusion criteria. After selection process, all included records were screened using a data extraction form to obtain the necessary data. The total number of impacted teeth was 73, of which 29% were partially impacted. The overall complication rate was 24.6%. The most common complications were as follows: haematoma, nerve disturbances and local infections. Surgical extraction in patients above 60 years of age is fraught with a high risk of possible complications. © 2015 John Wiley & Sons A/S and The Gerodontology Association. Published by John Wiley & Sons Ltd.

Comparison of Depth of Anesthesia in Different Parts of Maxilla When Only Buccal Anesthesia Was Done for Maxillary Teeth Extraction

OpenAIRE

Isik, Kubilay; Kalayci, Abdullah; Durmus, Ercan

2011-01-01

Objective. Recently, some authors reported that maxillary teeth could be extracted without using palatal anesthesia, but they did not clearly specify the extracted teeth. This is important, because apparently the local anesthetic solution infiltrates the maxilla and achieves a sufficient anesthesia in the palatal side. Thus, thickness of the bone may affect the depth of anesthesia. The aim of this study was to compare the depth of anesthesia in different parts of the maxilla when only a bucca...

Non-destructive, preclinical evaluation of root canal anatomy of human teeth with flat-panel detector volume CT (FD-VCT)

International Nuclear Information System (INIS)

Heidrich, G.; Hassepass, F.; Dullin, C.; Grabbe, E.; Attin, T.; Hannig, C.

2005-01-01

Purpose: Successful endodontic diagnostics and therapy call for adequate depiction of the root canal anatomy with multimodal diagnostic imaging. The aim of the present study is to evaluate visualization of the endodont with flat-panel detector volume CT (FD-VCT). Materials and methods: 13 human teeth were examined with the prototype of a FD-VCT. After data acquisition and generation of volume data sets in volume rendering technology (VRT), the findings obtained were compared to conventional X-rays and cross-section preparations of the teeth. Results: The anatomical structures of the endodont such as root canals, side canals and communications between different root canals as well as dentricles could be detected precisely with FD-VCT. The length of curved root canals was also determined accurately. The spatial resolution of the system is around 140 μm. Only around 73% of the main root canals detected with FD-VCT and 87% of the roots could be visualized with conventional dental X-rays. None of the side canals, shown with FD-VCT, was detectable on conventional X-rays. In all cases the enamel and dentin of the teeth could be well delineated. No differences in image quality could be discerned between stored and freshly extracted teeth, or between primary and adult teeth. (orig.)

Microtomography evaluation of dental tissue wear surface induced by in vitro simulated chewing cycles on human and composite teeth

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Rossella Bedini

2012-01-01

Full Text Available In this study a 3D microtomography display of tooth surfaces after in vitro dental wear tests has been obtained. Natural teeth have been compared with prosthetic teeth, manufactured by three different polyceramic composite materials. The prosthetic dental element samples, similar to molars, have been placed in opposition to human teeth extracted by paradontology diseases. After microtomography analysis, samples have been subjected to in vitro fatigue test cycles by servo-hydraulic mechanical testing machine. After the fatigue test, each sample has been subjected again to microtomography analysis to obtain volumetric value changes and dental wear surface images. Wear surface images were obtained by 3D reconstruction software and volumetric value changes were measured by CT analyser software. The aim of this work has been to show the potential of microtomography technique to display very clear and reliable wear surface images. Microtomography analysis methods to evaluate volumetric value changes have been used to quantify dental tissue and composite material wear.

Determination of Radionuclide Concentration in Human Teeth in Najaf Governorate, Iraq

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Basim Almayahi

2017-12-01

Full Text Available Introduction: 238U decays with alpha particles emission into 234Th and the series ends with 206Pb. The unstable nucleus loses the energy with emitting ionizing alpha particles for reaching a stable state. It is undergoing alpha decay with decay energy (4.679 MeV. Alpha particles enter the human and animal bodies through inhalation of air or ingestion of contaminated food and water. This study aimed to perform a radiological analysis on the natural alpha particle emission rates of the human teeth as the biomarkers of radiation exposure and environmental pollution. Materials and Methods: This study was conducted on 68 teeth samples of 27 males and 41 females collected from the hospitals distributed across Najaf governorate, including many districts in Iraq. Alpha particle emission rates were measured using CR-39 nuclear track detector. Results: The mean emission rate of alpha particles in the female teeth was 0.0396±0.0070 mBq cm-2, which was relatively higher than that in the male teeth (0.0390±0.0048 mBq cm-2. Nevertheless, there was no significant difference between the female and male teeth regarding the emission rate of alpha particles. Furthermore, the emission rate of alpha particles in the teeth of the samples taken from Kufa (0.0417±0.0057 mBq cm-2 was higher than those obtained from Najaf (0.0384±0.0053 mBq cm-2. Conclusion: As the findings of this study revealed, Najaf governorate had a lower emission rate of alpha particles as compared to other sites of the worldwide. Therefore, it could be concluded that there is no negative consequence threatening the people’s health in this regard.

The effect of Trigona sp propolis from Luwu regency, South Sulawesi province, Indonesia on human enamel teeth (an in vitro study

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Ardo Sabir

2016-06-01

Full Text Available Propolis is a resinous substance produced by honey bees. It is well-known that propolis exhibits both antibacterial and anti-inflammatory activities therefore it has been used in folk medicine since primeval times.In recent years, propolis has been used as active component of mouthwashes in the attempt to treat gingivitis and periodontitis. The purpose of the present study is to know in vitro effect of Ethanolic Extract of Propolis (EEP solution on the microhardness of human enamel teeth. Solution of 0.125% EEP has been made from propolis which was collected from honeycombs in Luwu Regency, South Sulawesi Province. Aquadest and 1% povidone iodine were used as negative and positive control. Calcium, phosphate, fluoride concentrations and pH of the solutions were also measured using Atomic Absorption Spectroscopy and a digital pH meter. Ninety human maxillary first incisors which extracted for periodontal reasons were used in this study. The roots of the teeth were removed at the cementoenamel junction. The crowns were randomly divided into three groups of 30 each and were immersed in aquadest solution pH 8.4 (Group I; 0.125% EEP solution pH 4.3 (Group II or 1% povidone iodine solution pH 3.0 (Group III for 21, 42, 63, and 84 minutes respectively. A Vickers Hardness Tester was used to measure enamel surface microhardness before and after immersion. Data was statistically analyzed using one-way ANOVA and Tukey tests with significance level of 5%. The results showed that except immersed in aquadest, enamel microhardness increased after being immersed in EEP and povidone iodine solutions, although statistical analysis did not show significant differences (p>0.05 microhardness of enamel teeth before and after immersed in each group.In conclusion, immersion the teeth in 0.125% EEP solution pH 4.3 with 2.69 ppm phosphate, 1.49 ppm calcium, and 0.00 ppm fluoride concentrations for 84 minutes increased human enamel hardness in vitro.

Teeth: Among Nature's Most Durable Biocomposites

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Lawn, Brian R.; Lee, James J.-W.; Chai, Herzl

2010-08-01

This paper addresses the durability of natural teeth from a materials perspective. Teeth are depicted as smart biocomposites, highly resistant to cumulative deformation and fracture. Favorable morphological features of teeth at both macroscopic and microscopic levels contribute to an innate damage tolerance. Damage modes are activated readily within the brittle enamel coat but are contained from spreading catastrophically into the vulnerable tooth interior in sustained occlusal loading. Although tooth enamel contains a multitude of microstructural defects that can act as sources of fracture, substantial overloads are required to drive any developing cracks to ultimate failure—nature's strategy is to contain damage rather than avoid it. Tests on model glass-shell systems simulating the basic elements of the tooth enamel/dentin layer structure help to identify important damage modes. Fracture and deformation mechanics provide a basis for analyzing critical conditions for each mode, in terms of characteristic tooth dimensions and materials properties. Comparative tests on extracted human and animal teeth confirm the validity of the model test approach and point to new research directions. Implications in biomechanics, especially as they relate to dentistry and anthropology, are outlined.

In-vitro study investigating influence of toothpaste containing green tea extract on the microhardness of demineralized human enamel

Science.gov (United States)

Febrian, K.; Triaminingsih, S.; Indrani, DJ

2017-08-01

The aim of this study was to analyze the influence of toothpaste containing green tea extract on the microhardness of demineralized enamel. Human tooth, which was demineralised in citric acid solution, had a toothpaste containing green tea extract of concentration of 5, 10 or 15% application. Microhardness measurement was carried out on each enamel surface of the teeth for initial, after the demineralization and after application of the tooth pastes. It showed that there was significant decrease between enamel microhardness of the teeth at the initial condition and after demineralization. After application of the toothpaste containing green tea extract of each concentration the microhardnss increased significantly. However, there the microhardness was insignificant between the applications of each green tea concentration.

Atmospheric nuclear weapons test history narrated by carbon-14 in human teeth

International Nuclear Information System (INIS)

Nishizawa, Kunihide; Nagatsu, Toshiharu; Togari, Akifumi; Matsumoto, Shosei

1991-01-01

The atmospheric testing of nuclear weapons since 1945 caused a significant increase in the concentration of atmospheric 14 C. The 14 C concentration in plants that assimilate 14 C directly by photosynthesis reflects the atmospheric 14 C concentration. Carbon-14 is then transferred into the human body through the food chain. Based on animal experiments, the collagen in human teeth is metabolically inert after its formation. This implies that the collagen of each tooth retains the 14 C concentration which reflects the 14 C concentration in the blood at the time collagen metabolism ceased. The distribution of the 14 C concentration in the collagen of teeth from subjects of various ages would follow a pattern similar to that shown by soft tissues. In this paper the authors elucidate the relationship between the number of nuclear weapon tests and the distribution of 14 C concentration in teeth

Zinc, lead and copper in human teeth measured by induced coupled argon plasma atomic emission spectroscopy (ICP-AES)

Energy Technology Data Exchange (ETDEWEB)

Chew, L.T.; Bradley, D.A. E-mail: D.A.Bradley@exeter.ac.uk; Mohd, Y.; Jamil, M

2000-11-15

Inductively Coupled Argon Plasma Atomic Emission Spectroscopy (ICP-AES) has been used to determine Pb, Zn and Cu levels in 47 exfoliated human teeth (all of which required extraction for orthodontic reasons). Lead concentrations for the group were 1.7 {mu}g (g tooth mass){sup -1} to 40.5 {mu}g (g tooth mass){sup -1}, with a median of 9.8 {mu}g (g tooth mass){sup -1}. A median lead level in excess of the group value was found for the teeth of six lorry drivers who were included in the study. A more significant enhancement was found for the seven subjects whose age was in excess of 60 years. The median values for Zn and Cu were 123.0 and 0.6 {mu}g (g tooth mass){sup -1} respectively. Present values for tooth-Zn are lower than published data for other ethnic groups.

Caries induced cytokine network in the odontoblast layer of human teeth

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Horst Jeremy A

2011-01-01

Full Text Available Abstract Background Immunologic responses of the tooth to caries begin with odontoblasts recognizing carious bacteria. Inflammatory propagation eventually leads to tooth pulp necrosis and danger to health. The present study aims to determine cytokine gene expression profiles generated within human teeth in response to dental caries in vivo and to build a mechanistic model of these responses and the downstream signaling network. Results We demonstrate profound differential up-regulation of inflammatory genes in the odontoblast layer (ODL in human teeth with caries in vivo, while the pulp remains largely unchanged. Interleukins, chemokines, and all tested receptors thereof were differentially up-regulated in ODL of carious teeth, well over one hundred-fold for 35 of 84 genes. By interrogating reconstructed protein interaction networks corresponding to the differentially up-regulated genes, we develop the hypothesis that pro-inflammatory cytokines highly expressed in ODL of carious teeth, IL-1β, IL-1α, and TNF-α, carry the converged inflammatory signal. We show that IL1β amplifies antimicrobial peptide production in odontoblasts in vitro 100-fold more than lipopolysaccharide, in a manner matching subsequent in vivo measurements. Conclusions Our data suggest that ODL amplifies bacterial signals dramatically by self-feedback cytokine-chemokine signal-receptor cycling, and signal convergence through IL1R1 and possibly others, to increase defensive capacity including antimicrobial peptide production to protect the tooth and contain the battle against carious bacteria within the dentin.

Characterization of Coronal Pulp Cells and Radicular Pulp Cells in Human Teeth.

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Honda, Masaki; Sato, Momoko; Toriumi, Taku

2017-09-01

Dental pulp has garnered much attention as an easily accessible postnatal tissue source of high-quality mesenchymal stem cells (MSCs). Since the discovery of dental pulp stem cells (DPSCs) in permanent third molars, stem cells from human exfoliated deciduous teeth and from supernumerary teeth (mesiodentes) have been identified as a population distinct from DPSCs. Dental pulp is divided into 2 parts based on the developing stage: the coronal pulp and the radicular pulp. Root formation begins after the crown part is completed. We performed a sequential study to examine the differences between the characteristics of coronal pulp cells (CPCs) and radicular pulp cells (RPCs) from permanent teeth, mesiodentes, and deciduous teeth. Interestingly, although we have not obtained any data on the difference between CPCs and RPCs in permanent teeth, there are some differences between the characteristics of CPCs and RPCs from mesiodentes and deciduous teeth. The MSC characteristics differed between the RPCs and CPCs, and the reprogramming efficiency for the generation of induced pluripotent stem cells was greater in RPCs than in CPCs from deciduous teeth. The proportion of CD105 + cells in CPCs versus that in RPCs varied in mesiodentes but not in permanent teeth. The results indicate that the proportion of CD105 + cells is an effective means of characterizing dental pulp cells in mesiodentes. Taken together, the stem cells in deciduous and supernumerary teeth share many characteristics, such as a high proliferation rate and an immunophenotype similar to that of DPSCs. Thus, mesiodentes accidentally encountered on radiographs by the general dental practitioner might be useful for stem cell therapy. Copyright © 2017 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Distribution of the amelogenin protein in developing, injured and carious human teeth

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Thimios eMitsiadis

2014-12-01

Full Text Available Amelogenin is the major enamel matrix protein with key roles in amelogenesis. Although for many decades amelogenin was considered to be exclusively expressed by ameloblasts, more recent studies have shown that amelogenin is also expressed in other dental and no-dental cells. However, amelogenin expression in human tissues remains unclear. Here, we show that amelogenin protein is not only expressed during human embryonic development but also in pathological conditions such as carious lesions and injuries after dental cavity preparation. In developing embryonic teeth, amelogenin stage-specific expression is found in all dental epithelia cell populations but with different instensities. In the different layers of enamel matrix, waves of positive versus negative immunostaining for amelogenin are detected suggesting that the secretion of amelogenin protein is orchestreted by a biological clock. Amelogenin is also expressed transiently in differentiating odontoblasts during predentin formation, but was absent in mature functional odontoblasts. In intact adult teeth, amelogenin was not present in dental pulp, odontoblasts, and dentin. However, in injured and carious adult human teeth amelogenin is strongly re-expressed in newly differentiated odontoblasts and is distributed in the dentinal tubuli under the lesion site. In an in vitro culture system, amelogenin is expressed preferentially in human dental pulp cells that start differentiating into odontoblast-like cells and form mineralization nodules. These data suggest that amelogenin plays important roles not only during cytodifferentiation, but also during tooth repair processes in humans.

Ectopic Hard Tissue Formation by Odonto/Osteogenically In Vitro Differentiated Human Deciduous Teeth Pulp Stem Cells.

Science.gov (United States)

Kim, Seunghye; Song, Je Seon; Jeon, Mijeong; Shin, Dong Min; Kim, Seong-Oh; Lee, Jae Ho

2015-07-01

There have been many attempts to use the pulp tissue from human deciduous teeth for dentin or bone regeneration. The objective of this study was to determine the effects of odonto/osteogenic in vitro differentiation of deciduous teeth pulp stem cells (DTSCs) on their in vivo hard tissue-forming potential. DTSCs were isolated from extracted deciduous teeth using the outgrowth method. These cells were exposed to odonto/osteogenic stimuli for 4 and 8 days (Day 4 and Day 8 groups, respectively), while cells in the control group were cultured in normal medium. The in vitro differentiated DTSCs and the control DTSCs were transplanted subcutaneously into immunocompromised mice with macroporous biphasic calcium phosphate and sacrificed at 8 weeks post-implantation. The effect of odonto/osteogenic in vitro differentiation was evaluated using alkaline phosphatase (ALP) staining and quantitative reverse transcription polymerase chain reaction (RT-PCR). The in vivo effect was evaluated by qualitative RT-PCR, assessment of ALP activity, histologic analysis, and immunohistochemical staining. The amount of hard tissue was greater in Day 4 group than Day 8 group (p = 0.014). However, Day 8 group generated lamellar bone-like structure, which was immunonegative to anti-human dentin sialoprotein with significantly low expression level of DSPP compared with the control group (p = 0.008). This study demonstrates that odonto/osteogenic in vitro differentiation of DTSCs enhances the formation of bone-like tissue, instead of dentin-like tissue, when transplanted subcutaneously using MBCP as a carrier. The odonto/osteogenic in vitro differentiation of DTSCs may be an effective modification that enhances in vivo bone formation by DTSCs.

Vascular status in human primary and permanent teeth in health and disease.

Science.gov (United States)

Rodd, Helen D; Boissonade, Fiona M

2005-04-01

The present study sought to compare the vascular status of human primary teeth with that of human permanent teeth, and to determine whether caries or painful pulpitis was associated with changes in vascularity. Coronal pulps were removed from 62 primary and 62 permanent mandibular molars with a known pain history. Teeth were categorized as intact, moderately carious or grossly carious. Pulp sections were labelled with Ulex europaeus I lectin (UEIL), which is a marker of human vascular endothelium. Image analysis was then used to quantify the percentage area of UEIL-labelled tissue (vascularity) and the number of blood vessels present within three regions: the pulp horn, the subodontoblastic region, and the mid-coronal pulp. Only the mid-coronal region of the primary tooth pulp was found to be significantly more vascular than the corresponding area of the permanent tooth pulp. Both dentitions showed a significant increase in vascularity within the pulp horn region with caries progression, but this was not accompanied by an increase in vessel number. There was no correlation between vascularity and pain symptoms. These findings suggest that the primary tooth pulp is more vascular than its successor within the mid-coronal region. However, the functional and clinical significance of this finding remains speculative.

Evaluation of thermal cooling mechanisms for laser application to teeth.

Science.gov (United States)

Miserendino, L J; Abt, E; Wigdor, H; Miserendino, C A

1993-01-01

Experimental cooling methods for the prevention of thermal damage to dental pulp during laser application to teeth were compared to conventional treatment in vitro. Pulp temperature measurements were made via electrical thermistors implanted within the pulp chambers of extracted human third molar teeth. Experimental treatments consisted of lasing without cooling, lasing with cooling, laser pulsing, and high-speed dental rotary drilling. Comparisons of pulp temperature elevation measurements for each group demonstrated that cooling by an air and water spray during lasing significantly reduced heat transfer to dental pulp. Laser exposures followed by an air and water spray resulted in pulp temperature changes comparable to conventional treatment by drilling. Cooling by an air water spray with evacuation appears to be an effective method for the prevention of thermal damage to vital teeth following laser exposure.

A study about teeth extraction of irradiated patients by head and neck cancer

Energy Technology Data Exchange (ETDEWEB)

Kim, Yong Kack; Park, Hyung Kook [Korea Cancer Center Hospital, Seoul (Korea, Republic of)

1996-12-01

Radiation therapy, in addition to its therapeutic effects, cause several complications in oral region. As a result of radiation, the blood supply to bone is decreased, and large areas of hypocellular, hypovascular, hypoxic tissue are created that are devoid of functioning fibroblasts and osteobasts. Therefore, the extraction of teeth after irradiation to the jaws has generally been regarded as a potentially hazardous procedure because of the possible initiation of osteradionecrosis. Hyperbaric oxygen therapy appears to assist in salvaging irradiated tissue by tissue angioneogenesis in marginally viable tissue induced by high oxygen tissue level. Hyperbaric oxygen therapy is beneficial for patients at risk for the development of osteoradionecrosis, such as irradiated patients requiring tooth extraction. We obtained good results when extraction is performed with hyperbaric oxygen therapy in 17 cases with head and neck malignancy and present results with review of literatures. (author). 35 refs., 2 tabs.

A study about teeth extraction of irradiated patients by head and neck cancer

International Nuclear Information System (INIS)

Kim, Yong Kack; Park, Hyung Kook

1996-12-01

Radiation therapy, in addition to its therapeutic effects, cause several complications in oral region. As a result of radiation, the blood supply to bone is decreased, and large areas of hypocellular, hypovascular, hypoxic tissue are created that are devoid of functioning fibroblasts and osteobasts. Therefore, the extraction of teeth after irradiation to the jaws has generally been regarded as a potentially hazardous procedure because of the possible initiation of osteradionecrosis. Hyperbaric oxygen therapy appears to assist in salvaging irradiated tissue by tissue angioneogenesis in marginally viable tissue induced by high oxygen tissue level. Hyperbaric oxygen therapy is beneficial for patients at risk for the development of osteoradionecrosis, such as irradiated patients requiring tooth extraction. We obtained good results when extraction is performed with hyperbaric oxygen therapy in 17 cases with head and neck malignancy and present results with review of literatures. (author). 35 refs., 2 tabs

Measurement of Ca, Zn and Sr in enamel of human teeth by XRF

Energy Technology Data Exchange (ETDEWEB)

Wielopolski, L.; Featherstone, J.D.B.; Cohn, S.H.

1984-01-01

Energy dispersive x-ray fluorescence (EDXRF) has been employed to measure Ca, Zn, and Sr in enamel of human teeth. The calibration of the EDXRF system was performed by comparing Sr/Ca ratios with values obtained by atomic absorption analysis of acid etched biopsies of the enamel surface. Two calibration lines were obtained, one line for untreated teeth and the second line for teeth immersed (treated) in solutions containing Sr. A simple analytical model demonstrated that the two calibration lines were the result of the difference in the depth of the enamel sampled by EDXRF and by the acid-etched biopsy. The multi-elemental, non-destructive and quantitative aspects of EDXRF permit the sequential monitoring of the effects of Sr and Zn ions on the mineralization and demineralization processes in human enamel. The portability of the system and adaptability to non-invasive measurements makes it suitable for field studies. 26 references, 4 figures.

Measurement of Ca, Zn and Sr in enamel of human teeth by XRF

International Nuclear Information System (INIS)

Wielopolski, L.; Featherstone, J.D.B.; Cohn, S.H.

1984-01-01

Energy dispersive x-ray fluorescence (EDXRF) has been employed to measure Ca, Zn, and Sr in enamel of human teeth. The calibration of the EDXRF system was performed by comparing Sr/Ca ratios with values obtained by atomic absorption analysis of acid etched biopsies of the enamel surface. Two calibration lines were obtained, one line for untreated teeth and the second line for teeth immersed (treated) in solutions containing Sr. A simple analytical model demonstrated that the two calibration lines were the result of the difference in the depth of the enamel sampled by EDXRF and by the acid-etched biopsy. The multi-elemental, non-destructive and quantitative aspects of EDXRF permit the sequential monitoring of the effects of Sr and Zn ions on the mineralization and demineralization processes in human enamel. The portability of the system and adaptability to non-invasive measurements makes it suitable for field studies. 26 references, 4 figures

Measurement of Ca, Zn, and Sr in enamel of human teeth by XRF

International Nuclear Information System (INIS)

Wielopolski, L.; Featherstone, J.D.b.; Cohn, S.H.

1984-01-01

Energy dispersive x-ray fluorescence (EDXRF) has been employed to measure Ca, Zn, and Sr in enamel of human teeth. The calibration of the EDXRF system was performed by comparing Sr/Ca ratios with values obtained by atomic absorption analysis of acid etched biopsies of the enamel surface. Two calibration lines were obtained, one line for untreated teeth and the second line for teeth immersed (treated) in solutions containing Sr. A simple analytical model demonstrated that the two calibration lines were the result of the difference in the depth of the enamel sampled by EDXRF and by the acid-etched biopsy. The multi-elemental, non-destructive and quantitative aspects of EDXRF permit the sequential monitoring of the effects of Sr and Zn ions on the mineralization and demineralization processes in human enamel. The portability of the system and adaptability to non-invasive measurements makes it suitable for field studies. 26 references, 4 figures

Near-IR imaging of cracks in teeth

Science.gov (United States)

Fried, William A.; Simon, Jacob C.; Lucas, Seth; Chan, Kenneth H.; Darling, Cynthia L.; Staninec, Michal; Fried, Daniel

2014-02-01

Dental enamel is highly transparent at near-IR wavelengths and several studies have shown that these wavelengths are well suited for optical transillumination for the detection and imaging of tooth decay. We hypothesize that these wavelengths are also well suited for imaging cracks in teeth. Extracted teeth with suspected cracks were imaged at several wavelengths in the near-IR from 1300-1700-nm. Extracted teeth were also examined with optical coherence tomography to confirm the existence of suspected cracks. Several teeth of volunteers were also imaged in vivo at 1300-nm to demonstrate clinical potential. In addition we induced cracks in teeth using a carbon dioxide laser and imaged crack formation and propagation in real time using near-IR transillumination. Cracks were clearly visible using near-IR imaging at 1300-nm in both in vitro and in vivo images. Cracks and fractures also interfered with light propagation in the tooth aiding in crack identification and assessment of depth and severity.

[Comparative study of complications among routine method,high speed turbine handpiece and piezosurgery device after extraction of impacted wisdom teeth].

Science.gov (United States)

Guo, Zhao-zhong; Zhang, Heng; Li, Yan; Li, Xin; Liu, Yin; Wang, Yang; Yuan, Chun-xia; Liu, Xue

2012-04-01

To investigate complications in extraction of complicated impacted wisdom teeth whose root apex near to the inferior alveolar nerve(IAN) by using routine method(chisels),high speed turbine handpiece and piezosurgery device respectively. Three hundred qualified patients with impacted wisdom teeth were divided into three groups randomly,one hundred patients in group A were extracted by routine method, one hundred patients in group B were extracted by high speed turbine handpiece, and one hundred patients in group C were extracted by piezosurgery device. The operation time, postoperative pain duration,dry socket and IAN injury were compared between each two groups. All statistical analysis was performed using SPSS 13.0 software package. Differences between groups were compared using a paired t test (quantitative data) or Chi-square test (qualitative data). The operation time in group A was(14.12±0.12)min, (7.22±0.15)min in group B, (25.23±0.32)min in group C; Significant difference was found between group A and group B(Ppiezosurgery device is more effective in reducing postoperative complications.

Allogeneic stem cells derived from human exfoliated deciduous teeth (SHED for the management of periapical lesions in permanent teeth: Two case reports of a novel biologic alternative treatment

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Madu Ghana Shyam Prasad

2017-06-01

Full Text Available Stem cells are the pluripotent cells that have the capacity to differentiate into other specialized cells. Recently, many experiments have been conducted to study the potentiality of stem cells in the tissue regeneration. We report two cases treated utilizing stem cells from human exfoliated deciduous teeth (SHED in the management of periapical lesions in permanent teeth. Two normal human deciduous teeth from children, 7‒8 years of age, were collected to isolate stem cells. Two patients, one with periapical pathology alone and the other with periapical lesion along with an open apex in young permanent teeth, were selected for the study. After initial debridement of the root canals, homing of SHED was carried out and the access cavity was sealed using glass-ionomer cement. Clinical examination after 7 days, 30 days, 90 days, 180 days and 365 days revealed no symptoms. Closure of open apex and periapical tissue healing were observed radiographically at one-month review and maintained until 365-day review. Positive response to electric pulp testing was recorded for the treated teeth from the 3- to 12-month follow-ups. The treated cases demonstrated complete resolution of periapical radiolucency in a span of 30 days, which was faster than the conventional methods. SHED could be considred effective in treating the periapical lesions and open apex in permanent teeth.

Autotransplantation of Third Molars With Platelet-Rich Plasma for Immediate Replacement of Extracted Non-Restorable Teeth: A Case Series.

Science.gov (United States)

Gonzalez-Ocasio, Jorge; Stevens, Mark

2017-09-01

The aim of this study was to examine the use of platelet-rich plasma (PRP) for autotransplantation of third molars as a successful technique to provide immediate tooth structure for space maintenance and masticatory function when premature loss of a permanent tooth occurs and other dental restorative options are not indicated. This study included 10 healthy patients 10 to 17 years of age with at least 1 immature third molar (one to two thirds of root formation) used to replace extracted non-restorable teeth. Eleven third molars were transplanted and adapted to sockets of the extracted teeth with the adjunct of PRP. Transplanted teeth were stabilized to the adjacent teeth using orthodontic wires and dental composite for 1 month. Patients were followed for 1 year. Function, tooth vitality, root development, and periodontal health were recorded. All 10 patients had functioning asymptomatic transplanted teeth, with physiologic tooth mobility after splint removal at 1 month and after 1 year. All 10 patients had positive tooth vitality (by cold test) at 3, 6, and 12 months; all transplants showed positive root development (average growth, 2.01 mm) confirmed and measured using periapical radiographs. No patients required root canal therapy at any point in the study. Periodontal assessments were performed at the scheduled follow-up appointments with circumferential periodontal probing. Periodontal health was maintained because probing depths were shallower than 4 mm during the 1-year follow-up. Autotransplantation of immature third molars with PRP shows excellent results and should be considered a viable option for premature loss of permanent molars. PRP might have other advantages, such as root promotion and neurosensory development. Published by Elsevier Inc.

Development and validation of a gas chromatography-mass spectrometry assay for opiates and cocaine in human teeth.

Science.gov (United States)

Pellegrini, Manuela; Casá, Adriana; Marchei, Emilia; Pacifici, Roberta; Mayné, Ruth; Barbero, Vanessa; Garcia-Algar, Oscar; Pichini, Simona

2006-02-24

A procedure based on gas chromatography-mass spectrometry (GC-MS) is described for determination of opiates (6-monoacetylmorphine, morphine and codeine) and cocaine and metabolites (cocaine, benzoylecgonine and cocaethylene) in human teeth. After addition of nalorphine as internal standard, pulverized samples were incubated in HCl at 37 degrees C for 18 h. Then, after pH adjustment to 6, and the analytes were extracted with two volumes of 3 ml of chloroform/isopropanol (9:1). Chromatography was performed on a fused silica capillary column and analytes were determined in the selected-ion-monitoring (SIM) mode. The assay was validated in the range 7.5 (6.0 in case of codeine) to 500 ng/g with mean absolute recoveries ranged between 74.1 and 92.1% for the different analytes and precision and accuracy always better than 15%. The method was applied to the analysis of teeth from drug-addicts to assess past chronic consumption and verify self-reported declarations. In case of opiates, concentration range was 36.5-570.0 ng/g for 6-monoacetylmorphine, 8.7-154.8 ng/g for morphine and 7.9-127.9 ng/g for codeine. Cocaine concentration ranged between 5.6 and 57.2 ng/g with its principal metabolite benzoylecgonine varying from 12.6 to 81.7 ng/g and cocaethylene present in only one sample at 10 ng/g value. Teeth can be a promising non-invasive biological matrix in biomedical analysis for both clinical and forensic purposes.

Structure and microstructure of coronary dentin in non-erupted human deciduous incisor teeth

Directory of Open Access Journals (Sweden)

Costa Luciane R.R S.

2002-01-01

Full Text Available The dentin structure of non-erupted human deciduous mandibular and maxillary central and lateral incisor teeth was studied employing light and scanning electron microscopy. For light microscopy, nitric-acid-demineralized and ground sections were used. The sections were stained by hematoxylin-eosin, picrosirius and azo-carmim methods, and ground specimens were prepared using a carborundum disk mounted in a handpiece. For SEM study, teeth were frozen in liquid nitrogen and fractured at longitudinal and transversal directions. Structurally, demineralization and ground methods revealed tubules with primary and secondary curvatures, canaliculi, giant tubules, interglobular dentin, predentin, and intertubular dentin. Scanning electron microscopy showed three-dimensional aspects of dentinal tubules, canaliculi, peritubular dentin, intertubular dentin, and predentin. This study contributes to knowledge about dentin morphology showing characteristics of teeth not yet submitted to mastication stress.

Assessment of caries status among schoolchildren according to decayed-missing-filled teeth/decayed-extract-filled teeth index, International Caries Detection and Assessment System, and Caries Assessment Spectrum and Treatment criteria

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E Rajendra Reddy

2017-01-01

Full Text Available Background: Detection and evaluation of dental caries is of epidemiological importance. Its early detection is important to commence appropriate treatment planning. Cavitated, noncavitated, and initial lesions of dental caries can be detected by various indices. Objectives: The objective of the study was to assess the caries experience in schoolchildren using decayed-missing-filled teeth (DMFT/decayed-extracted-filled teeth (deft, International Caries Detection and Assessment System-II (ICDAS-II, and Caries Assessment Spectrum and Treatment (CAST systems. Materials and Methods: An epidemiological survey was carried out among 1550 schoolchildren (37,644 teeth between the age ranges of 4 and 14 years. American Dental Association type III examination was performed using plane mouth mirrors and community periodontal index probes using DMFT/deft, ICDAS II, and CAST indices. Results: Out of 37,644 teeth examined, 2,718 teeth had shown caries. Caries experience with DMFT/deft index was 5.54%. Highest score of DMFT was observed in deciduous dentition period (59.02%. Overall prevalence of dental caries with ICDAS and CAST system was 6.7% and 6.95%, respectively. The highest percentage of noncavitated lesions (ICDAS - 2.26% and CAST - 3.9% and greater prevalence of caries among deciduous teeth (ICDAS - 53.2% and CAST - 58.7% was observed with both ICDAS and CAST systems. Conclusion: A high prevalence of noncavitated lesions and less number of sealants and restorations indicates the lack of awareness for prevention and treatment of oral diseases, which suggests a strong need for preventive and operative treatments.

Characteristics of Teeth: A Review of Size, Shape, Composition, and Appearance of Maxillary Anterior Teeth.

Science.gov (United States)

McGowan, Steve

2016-03-01

Although digital technologies play an increasingly integral role in dentistry, there remains a need for dental professionals to understand the fundamentals of tooth anatomy, form, occlusion, and color science. In this article, the size, shape, composition, and appearance of maxillary anterior teeth will be discussed from esthetic and functional perspectives. A total of 600 extracted maxillary incisors were studied: 200 each of central incisors, lateral incisors, and cuspids. The purpose of the article is to exhibit and discuss factors that make teeth unique and diverse. Understanding these aspects of teeth aids dental professionals in more effectively creating realistic and highly esthetic restorations for patients.

Measurement of uranium in human teeth and kidney stones with the fission track technique

International Nuclear Information System (INIS)

Vartanian, R.

1986-01-01

The measurement of uranium in human teeth and in kidney stones was carried out using the fission track activation technique. In this determination 2759 and 2205 absolute counts of tracks for teeth samples and 1689 tracks for kidney stone samples were performed, respectively. The results are as follows: xsub(tooth) (1)=(0.227+-0.006) ppm, xsub(tooth) (2)=(0.143+-0.007) ppm and xsub(kidney)=(0.568+-0.020) ppm. The experimental method is described and the results are discussed. (author)

Incremental lines in root cementum of human teeth: An approach to their role in age estimation using polarizing microscopy

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Aggarwal Pooja

2008-01-01

Full Text Available Age estimation is an important factor in the identification of an individual in forensic science. The hard tissues of the human dentition are able to resist decay and degradation long after other tissues are lost. This resistance has made teeth useful indicators for age calculation. Recent research indicates that tooth cementum annulations (TCA may be used more reliably than any other morphological or histological traits of the adult skeleton for age estimation. The purpose of this study was to examine the correlation between age and the number of incremental lines in human dental cementum and to ascertain the best method of studying cementum with respect to different forms of microscopy. Thirty nonrestorable teeth were extracted from 20 people, and longitudinal ground section of each tooth was prepared. Photomicrographs of the area at the junction of apical and middle third of the root under light and polarized microscope were taken. The cementum was composed of multiple light and dark bands that were counted on the photomicrograph with the help of image analysis software and added to the average eruption time of individual tooth. The predicted age of the individual was thus obtained. Results showed a significant correlation between the predicted age and actual chronological age of the individual. These data indicate that quantitation of cementum annuli is a moderately reliable means for age estimation in humans and polarizing microscopy is a better means of visualizing incremental lines of cementum compared to light microscopy.

Iron deposition in modern and archaeological teeth

Energy Technology Data Exchange (ETDEWEB)

Williams, A.-M.M., E-mail: AnneMarie.Williams@utas.edu.au [School of Medicine, Private Bag 34, University of Tasmania, Hobart 7001 (Australia); Siegele, R. [Australian Nuclear Science and Technology Organisation, PMB 1, Menai, NSW 2234 (Australia)

2014-09-15

Iron surface concentrations and profile maps were measured on the enamel of archaeological and modern teeth to determine how iron is deposited in tooth enamel and if it was affected by the post-mortem environment. Teeth from Australian children who died in the second half of the 19th century were compared with contemporary teeth extracted for orthodontic purposes. Surface analysis of the teeth was performed using the 3 MV Van Der Graff Accelerator at The Australian Nuclear Science and Technology Organisation (ANSTO), Sydney, Australia. A small sample of teeth were then cut in the mid sagittal plane and analysed using ANSTO High Energy Heavy Ion Microprobe. Maps and linear profiles were produced showing the distribution of iron across the enamel. Results show that both the levels and distribution of iron in archaeological teeth is quite different to contemporary teeth, raising the suggestion that iron has been significantly altered by the post-mortem environment.

Iron deposition in modern and archaeological teeth

International Nuclear Information System (INIS)

Williams, A.-M.M.; Siegele, R.

2014-01-01

Iron surface concentrations and profile maps were measured on the enamel of archaeological and modern teeth to determine how iron is deposited in tooth enamel and if it was affected by the post-mortem environment. Teeth from Australian children who died in the second half of the 19th century were compared with contemporary teeth extracted for orthodontic purposes. Surface analysis of the teeth was performed using the 3 MV Van Der Graff Accelerator at The Australian Nuclear Science and Technology Organisation (ANSTO), Sydney, Australia. A small sample of teeth were then cut in the mid sagittal plane and analysed using ANSTO High Energy Heavy Ion Microprobe. Maps and linear profiles were produced showing the distribution of iron across the enamel. Results show that both the levels and distribution of iron in archaeological teeth is quite different to contemporary teeth, raising the suggestion that iron has been significantly altered by the post-mortem environment

Immunohistochemical studies of the periodontal membrane in primary teeth

DEFF Research Database (Denmark)

Bille, Marie-Louise Bastholm; Nolting, Dorrit; Kjær, Inger

2009-01-01

Objectives. To describe the periodontal membrane of human primary teeth immunohistochemically, while focusing on the epithelial layer of Malassez, fibers, and peripheral nerves, and to compare the findings with those of a previous study of human permanent teeth. Material and methods. Nineteen human...... could be identical to those in regions with no resorption. Conclusion. In regions without resorption, spatial organization of the periodontal membrane of primary teeth was similar to that of permanent teeth, although the number and distribution of epithelial cells and fibers differed. In regions...

Changes in the chemical composition of mineralised teeth in children after antineoplastic treatment.

Science.gov (United States)

Krasuska-Sławińska, Ewa; Dembowska-Bagińska, Bożenna; Brożyna, Agnieszka; Olczak-Kowalczyk, Dorota; Czarnowska, Elżbieta; Sowińska, Agnieszka

2018-01-01

Chemotherapy, neoplasms, and their complications linked to malabsorption, malnutrition, and metabolic disorders may lead to improper tooth development and frequent severe caries in patients during/after antineoplastic treatment and to a more frequent improper tooth development in patients undergoing chemotherapy during odontogenesis. However, the causes of these abnormalities remain unknown; there are no studies on the impact of antineoplastic treatment and its complications on the chemical composition of mineralised teeth. To compare the chemical composition of mineralised teeth extracted due to complicated caries in children after chemotherapy, and of teeth extracted due to orthodontic treatment in generally healthy children. The treatment group included five teeth extracted due to complicated caries in children after antineoplastic treatment. The control group included five teeth extracted due to orthodontic treatment in generally healthy children. The chemical composition of enamel, dentine, cementum, interior of the canal, and enamel abnormalities in teeth extracted from patients after chemotherapy and in generally healthy patients were assessed with energy-dispersive X-ray spectroscopy. Results were analysed statistically. The magnesium (Mg) and zinc (Zn) mass contents in the enamel of patients after chemotherapy increased and so did the calcium (Ca) to phosphorus (P) ratio when compared to controls. Areas with abnormal enamel in patients after chemotherapy had lower concentrations of Ca and P, and higher concentrations of trace elements (Mg, Cl, and Na). The levels of the assessed elements in dentine, cementum, and inside the canal were similar in both groups of teeth.

Insights into the processes behind the contamination of degraded human teeth and bone samples with exogenous sources of DNA

DEFF Research Database (Denmark)

Gilbert, M. T. P.; Hansen, Anders J.; Willerslev, E.

2006-01-01

A principal problem facing human DNA studies that use old and degraded remains is contamination from other sources of human DNA. In this study we have attempted to contaminate deliberately bones and teeth sampled from a medieval collection excavated in Trondheim, Norway, in order to investigate......, prior to assaying for the residual presence of the handler's DNA. Surprisingly, although our results suggest that a large proportion of the teeth were contaminated with multiple sources of human DNA prior to our investigation, we were unable to contaminate the samples with further human DNA. One...

Effect Of Storage And Disinfection Methods Of Extracted Bovine Teeth On Bond Strength To Dentin

OpenAIRE

Humel M.M.C.; Oliveira M.T.; Cavalli V.; Giannini M.

2007-01-01

The aim of this study was to evaluate the effect of storage and disinfection methods (SDM) on bond strength (BS) to bovine dentin, using two adhesive systems. Adper Single Bond and Clearfil Protect Bond. Method: Extracted bovine teeth were assigned to the following SDM: 100% Humidity (HU); Gamma Radiation (GR); Autoclave (AU): 0.10g/mL Thymol (TH); 10% Formatin (FO); Frozen (FR); 0.2% Sodium Azide (SA) and 0.5% Chloramine T (CT) (n=10). The GR and AU groups were submitted to sterilization met...

Is it better to leave or restore carious deciduous molar teeth? A preliminary study.

Science.gov (United States)

Tickle, M; Milsom, K; Kennedy, A

1999-10-01

The objective of this study was to compare the extraction and exfoliation experience of filled and unfilled carious deciduous molar teeth. The study was carried out in 1997 in four general dental practices in south Cheshire, UK and involved a longitudinal retrospective review of case notes. A quota sample of 20 case notes of children from each practice was selected according to strict criteria. Subjects had to: Have had experience of approximal caries in one or more of the deciduous molar teeth. Have a date of birth between 1st January 1984 and 31st December 1985. Be a regular attender and in continuous contact with the practice. Data were collected on a common data abstraction form. Variables measured included: Base-line dmft. Site and number of filled teeth. Site and number of unfilled carious teeth. Number of courses of antibiotics. Site and number of pulp therapies. Site, number, method (local or general anaesthetic) of extractions. Reasons for extraction. All teeth not recorded as being extracted were assumed to have exfoliated. In addition, information was collected on the dentists' treatment philosophies. A series of group discussions revealed that the four dentists fitted into two groups according to treatment philosophies; two dentists shared a philosophy of minimal intervention, the other two shared the same views of treating more radically. There was no significant difference between the proportion of filled teeth and the proportion of carious unfilled teeth that were extracted (chi-square 0.05 P = 0.83). A logistic regression showed that for each course of antibiotics administered the odds of having an extraction was multiplied by 5.5 and children who were patients of the interventionist dentists were five times more likely to have an extraction than patients of non-interventionist dentists. Although the study was preliminary in nature no clear benefit could be found in filling deciduous molar teeth against leaving carious teeth unfilled, if avoidance

Elemental composition of human teeth with emphasis on trace constituents: a review

Energy Technology Data Exchange (ETDEWEB)

Sachs, W H

1978-04-01

Literature covered by the current review is based on a search of Chemical Abstracts, 1917 through 1975. Early studies, pre-dating 1940, are referenced primarily for historical interest. Emphasis is on the micro-constituents of human teeth, those present at concentrations less than a few tenths of a percent by weight. Within this category of data, we have been primarily concerned with the radiochemically stable nuclides. The important relationship between caries and trace elements is covered only insofar as carious teeth exhibit properties with respect to trace element composition that differ from normal teeth. Having made these disclaimers, we note that an attempt has been made to cover the literature exhaustively; although some important results have undoubtedly been overlooked. It is our hope, however, that sufficient material has been included in this review to facilitate further recovery of data by interested individuals. In Chapter 1, analytical techniques that have been employed in this field are briefly presented; discussion centers on problems associated with preparation of specimens for analysis. Chapter 2 is devoted to topical coverage of data on the inorganic composition of teeth. An element-by-element tabulation of concentration data is provided, our statistical analysis of selected data explained, and evidence concerning several major factors thought to influence dental composition evaluated. These include provenance, age, sex, distribution, and tooth type/intermouth variation.

Tuberculate and odontoma type supernumerary teeth.

Science.gov (United States)

Tarján, Ildikó; Gyulai, Szabolcs G; Soós, Attila; Rózsa, Noémi

2005-11-01

An 8-and-a-half-year-old girl with supernumerary teeth of tuberculate and odontoma type is described. Treatment of the patient is carried out on conventional lines with a combination of surgical and orthodontic methods. The upper tuberculate type supernumerary teeth were extracted and, after surgical exposure, the upper permanent first incisors were aligned with removable appliances. After secondary dentition was completed, the lower odontoma type supernumerary tooth was removed surgically, and also the maxillary and mandibular first premolars were extracted because of severe crowding, and fixed orthodontic appliances were used to align the permanent dentition. Early diagnosis and treatment of this anomaly is necessary to avoid more serious consequences and to prevent severe orthodontic disturbances.

Evaluation of Related Factors in the Failure of Endodontically Treated Teeth: A Cross-sectional Study.

Science.gov (United States)

Olcay, Keziban; Ataoglu, Hanife; Belli, Sema

2018-01-01

The aim of this study was to review the factors related to the failure and extraction of unsuccessful endodontically treated teeth. A total of 1000 teeth treated with nonsurgical root canal therapy were analyzed, and the following information was recorded for each patient: reasons for failure and extraction, type of tooth, presence and type of coronal restoration, smoking status, age, gender, and level of education. One main reason was recorded for each failed tooth. The associations between reasons for failure, patient, and tooth were tested by using χ 2 analysis. Of the 1000 endodontically failed teeth analyzed in this study, 28.1% (n = 281) were extracted, 66% (n = 660) were re-treated, and 5.9% (n = 59) were treated with apical surgery. Among the reasons for failure, restorative and endodontic reasons were seen most frequently (43.9%, n = 439), whereas orthodontic reasons were seldom seen (0.1%, n = 1). The most common reason for extraction was for prosthetic reasons (40.8%), and perforation/stripping was the least common (2.9%). The mandibular first molars were the most frequently extracted teeth (27.4%, n = 77). The most common reason for the extraction of endodontically treated teeth was for prosthetic reasons. Among the reasons for failure, restorative and endodontic reasons were the most frequently seen, and orthodontic reasons were the most seldom. The teeth that failed most frequently were mandibular first molars, and the teeth that failed least frequently were maxillary third molars. The most common reason for the extraction of failed endodontically treated teeth was for prosthetic reasons. Copyright © 2017 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Anesthetic Efficacy of 4 % Articaine During Extraction of the Mandibular Posterior Teeth by Using Inferior Alveolar Nerve Block and Buccal Infiltration Techniques.

Science.gov (United States)

El-Kholey, Khalid E

2017-03-01

The study was designed to evaluate the anesthetic efficacy of 4 % articaine with 1:100,000 epinephrine (A100) in infiltration and inferior alveolar nerve block (IANB) anesthetic techniques for the pain control during extraction of the mandibular posterior teeth. This prospective randomized single-blind clinical trial included 100 patients needing extraction of at least two mandibular molars. Patients received either infiltration in the buccal vestibule opposite to the first molar supplemented with lingual infiltration or standard IANB with A100. For assessment of depth of anesthesia obtained by the two anaethetic techniques, presence or absence of pain during the extraction were rated using the visual analog scale. Fifty patients received infiltration anesthesia and fifty patients were anesthetized by IANB. The success rate of pain-free extraction after buccal infiltration was 94 %, whereas by using IANB with the same anesthetic it was 92 %. No statistical differences were detected in the success rates between the two anesthetic techniques ( P  = 0.15). Buccal Infiltration can be considered a good option during extraction of the mandibular molar and premolar teeth of course, with supplemental lingual anesthesia.

Fracture modes in human teeth.

Science.gov (United States)

Lee, J J-W; Kwon, J-Y; Chai, H; Lucas, P W; Thompson, V P; Lawn, B R

2009-03-01

The structural integrity of teeth under stress is vital to functional longevity. We tested the hypothesis that this integrity is limited by fracture of the enamel. Experiments were conducted on molar teeth, with a metal rod loaded onto individual cusps. Fracture during testing was tracked with a video camera. Two longitudinal modes of cracking were observed: median cracking from the contact zone, and margin cracking along side walls. Median cracks initiated from plastic damage at the contact site, at first growing slowly and then accelerating to the tooth margin. Margin cracks appeared to originate from the cemento-enamel junction, and traversed the tooth wall adjacent to the loaded cusp from the gingival to the occlusal surface. All cracks remained confined within the enamel shell up to about 550 N. At higher loads, additional crack modes--such as enamel chipping and delamination--began to manifest themselves, leading to more comprehensive failure of the tooth structure.

EPR dosimetry of irradiated human teeth

International Nuclear Information System (INIS)

Rodas Duran, J.E.; Panzeri, H.; Mascarenhas, S.

1985-01-01

The determination of the absorbed radiation dose in man may be made by Electron Paramagnetic Resonance (EPR) spectroscopy of dental enamel. We analysed the EPR signals for dental enamel submitted to gamma radiation in doses between 1 Gy and 25 Gy. We conclude that independent of the type of tooth analysed there exists a linear relation between the EPR signals and the absorbed doses. These studies were extended to enamel irradiated with gamma rays and with X rays in doses between 0.1 Gy and 0.6 Gy. The graph of the intensity of the EPR signals as a function of the dose has a slope of 0.22. This calibration may be used to calculate the absorbed dose for humans from a measurement of the EPR signal from small samples of enamel taken from any permanent tooth. Finally we comment on some EPR studies of effects of radiation of milk teeth. (author)

Accuracy of three-dimensional printing for manufacturing replica teeth.

Science.gov (United States)

Lee, Keun-Young; Cho, Jin-Woo; Chang, Na-Young; Chae, Jong-Moon; Kang, Kyung-Hwa; Kim, Sang-Cheol; Cho, Jin-Hyoung

2015-09-01

Three-dimensional (3D) printing is a recent technological development that may play a significant role in orthodontic diagnosis and treatment. It can be used to fabricate skull models or study models, as well as to make replica teeth in autotransplantation or tooth impaction cases. The aim of this study was to evaluate the accuracy of fabrication of replica teeth made by two types of 3D printing technologies. Fifty extracted molar teeth were selected as samples. They were scanned to generate high-resolution 3D surface model stereolithography files. These files were converted into physical models using two types of 3D printing technologies: Fused deposition modeling (FDM) and PolyJet technology. All replica teeth were scanned and 3D images generated. Computer software compared the replica teeth to the original teeth with linear measurements, volumetric measurements, and mean deviation measurements with best-fit alignment. Paired t-tests were used to statistically analyze the measurements. Most measurements of teeth formed using FDM tended to be slightly smaller, while those of the PolyJet replicas tended to be slightly larger, than those of the extracted teeth. Mean deviation measurements with best-fit alignment of FDM and PolyJet group were 0.047 mm and 0.038 mm, respectively. Although there were statistically significant differences, they were regarded as clinically insignificant. This study confirms that FDM and PolyJet technologies are accurate enough to be usable in orthodontic diagnosis and treatment.

Fluorine determination in human healthy and carious teeth using the PIGE technique

International Nuclear Information System (INIS)

Carvalho, M.L.; Karydas, A.G.; Casaca, C.; Zarkadas, Ch.; Paradellis, Th.; Kokkoris, M.; Nsouli, B.; Cunha, A.S.

2001-01-01

The purpose of this study is to determine and compare the fluorine concentration in human teeth from two different populations, living in the Portuguese quite isolated islands of Acores: S. Miguel and Terceira. Both populations have similar dietary habits, similar occupational activities, mostly rural, and the age of both populations is more or less the same, around 40 years. No chronic diseases were registered in any of the donors. The two groups are exposed to different levels of fluorine in drinking water. Terceira island has moderate fluorine concentration levels (1-2 μg g -1 ) while S. Miguel island is known for the high fluorine concentration levels in its water (>3 μg g -1 ), especially in one area known as Furnas. Thirty-three teeth, 17 healthy and 16 carious without restoration (14 incisors and canines, 7 premolars and 12 molars), were collected and analyzed for the determination of fluorine concentration in the dentine region, using the nuclear reaction 19 F(p,αγ) 16 O. The teeth were cross-sectioned along the vertical plane and polished, in order to obtain a smooth and plane surface of about 1 mm thickness. In this work an association between caries prevalence and fluorine content of drinking water is discussed and the variation of fluorine concentration among different types of teeth (canines and incisors, premolars, molars) and physical state (carious and non-carious) is examined

Penetration of 38% hydrogen peroxide into the pulp chamber in bovine and human teeth submitted to office bleach technique.

Science.gov (United States)

Camargo, Samira Esteves Afonso; Valera, Marcia Carneiro; Camargo, Carlos Henrique Ribeiro; Gasparoto Mancini, Maria Nadir; Menezes, Marcia Maciel

2007-09-01

This study evaluated the pulp chamber penetration of peroxide bleaching agent in human and bovine teeth after office bleach technique. All the teeth were sectioned 3 mm apical of the cement-enamel junction and were divided into 2 groups, A (70 third human molars) and B (70 bovine lateral incisors), that were subdivided into A1 and B1 restored by using composite resin, A2 and B2 by using glass ionomer cement, and A3 and B3 by using resin-modified glass ionomer cement; A4, A5, B4, and B5 were not restored. Acetate buffer was placed in the pulp chamber, and the bleaching agent was applied for 40 minutes as follows: A1-A4 and B1-B4, 38% hydrogen peroxide exposure and A5 and B5, immersion into distilled water. The buffer solution was transferred to a glass tube in which leuco crystal violet and horseradish peroxidase were added, producing a blue solution. The optical density of the blue solution was determined by spectrophotometer and converted into microgram equivalents of hydrogen peroxide. Data were submitted to analysis of variance and Dunnett, Kruskal-Wallis, and Tukey tests (5%). A higher level of hydrogen peroxide penetrated into the pulp chamber in resin-modified glass ionomer cements in bovine (0.79 +/- 0.61 microg) and human (2.27 +/- 0.41 microg) groups. The bleaching agent penetration into the pulp chamber was higher in human teeth for any experimental situation. The penetration of the hydrogen peroxide depends on restorative materials, and under the conditions of this study human teeth are more susceptible to penetration of bleaching agent into the pulp chamber than bovine teeth.

[Conservative treatment of deciduous teeth--a review].

Science.gov (United States)

Magnusson, B

1976-06-01

In all countries with a lack of manpower in dentistry, there is an unfortunate tendency to leave the primary teeth without proper conservative treatment. In addition to toothaches and poor esthetics, a neglected care of the primary dentition may result in several other untoward effects. Decayed deciduous teeth may cause such a discomfort during tooth-brushing that the child is prevented from learning good oral hygiene habits. With bad primary molars the child cannot chew properly, and may have to choose soft and often cariogenic food. When the permanent teeth erupt among the decayed deciduous teeth, there will be a greater chance for them to have carious attacks as well. Premature loss of primary molars may lead to malocclusion. It must also be kept in mind that the treatment of badly decayed teeth, including necessary extractions, may be difficult. This may cause fear of dental treatment. On the basis of current Swedish philosophies of treatment the author surveys various conservative procedures for deciduous teeth-amalgam therapy, stainless steel crowns, composites and disking.

Association Between Odontoma and Impacted Teeth.

Science.gov (United States)

Isola, Gaetano; Cicciù, Marco; Fiorillo, Luca; Matarese, Giovanni

2017-05-01

Odontoma is considered to be the most common odontogenic tumor of the oral cavity. Most odontomas are asymptomatic and are discovered during routine radiographic investigations and can cause disturbances in the eruption of the teeth, most commonly delayed eruption or deflection. By a retrospective study design, demographic and clinical data regarding patients who presented odontomas from year 1995 to 2015 were obtained in order and the influence of active therapy on the dentition and on the treatment of impacted teeth was analyzed. Forty-five patients (mean age 14.2 years) with 29 complex and 16 compound odontomas were included in this retrospective study. Initial symptoms were delayed eruption of permanent teeth (n = 25), pain (n = 6), swellings (n = 4), and no symptoms (n = 10); 31 patients were discovered by incidence, all of them via panoramic radiographs. The mandible/maxilla ratio was about 2:1 (31/15). Thirty-two out of 45 odontomas were in close proximity of at least 1 tooth (n = 21 at incisive). A total of 12 teeth were extracted (complex: n = 8; compound: n = 4). Of the nonextracted teeth, 33 teeth were displaced and retained. Of those, 29 teeth were aligned through orthodontic-surgical approach and 4 teeth erupted spontaneously after surgery during the follow-up period. An early detection of odontoma is more likely an accidental radiological finding, hence the need for routine radiographic analysis should be emphasized. Early diagnosis of odontomas in primary dentition is crucial in order to prevent later complications, such as impaction or failure of eruption of teeth.

Comparison of Calcium Hydroxide and Bioactive Glass after Direct Pulp Capping in Primary Teeth

Directory of Open Access Journals (Sweden)

R. Haghgoo

2007-12-01

Full Text Available Objective: Bioactive glass is often used as a filler material for repair of dental bone defects.In different studies osteogenic potential of this material was proved, but its dentinogenesisproperty is in doubt. The purpose of this study was to evaluate the histological pulp responses of Calcium hydroxide and Bioactive glass placed directly on exposed pulp tissues.Materials and Methods: Twenty teeth to be extracted due to orthodontic reasons were selected. These teeth were divided into two groups and treated with direct pulp capping.Calcium hydroxide was used for 10 teeth and Bioactive glass for 10 teeth. After 60 daysthe teeth were extracted and prepared for histological evaluation. Finally the data was analyzed with exact Fisher test.Results: All teeth treated with Calcium hydroxide showed inflammation. Internal resorption was seen in six teeth, abscess in five teeth and dentinal bridge in two teeth. Inflammationwas seen in three Bioactive glass samples and dentinal bridge in seven teeth, but internal resorption and abscess were not seen.Conclusion: Bioactive glass appears to be superior to Calcium hydroxide as a pulp capping agent in primary teeth.

Hidden contributions of the enamel rods on the fracture resistance of human teeth

OpenAIRE

Yahyazadehfar, M.; Bajaj, Devendra; Arola, Dwayne D.

2012-01-01

The enamel of human teeth is generally regarded as a brittle material with low fracture toughness. Consequently, the contributions of this tissue in resisting tooth fracture and the importance of its complex microstructure have been largely overlooked. In this study an experimental evaluation of the crack growth resistance of human enamel was conducted to characterize the role of rod (i.e. prism) orientation and degree of decussation on the fracture behavior of this tissue. Incremental crack ...

The effects of impacted premaxillary supernumerary teeth on permanent incisors

Energy Technology Data Exchange (ETDEWEB)

Jung, Yun Hoa; Kim, Ji Yeon; Cho, Bong Hae [School of Dentistry, Pusan National University, Yangsan (Korea, Republic of)

2016-12-15

The aim of this study was to examine the radiographic features associated with impacted premaxillary supernumerary teeth, to determine the relationship between their characteristics and their effects on permanent incisors, and to investigate the types of orthodontic treatment that patients received after the extraction of impacted supernumerary teeth. The clinical records and radiographs of 193 patients whose impacted premaxillary supernumerary teeth were removed were retrospectively reviewed, and 241 impacted supernumerary teeth were examined. Cone-beam computed tomographic images and panoramic radiographs were examined to determine the number, location, sagittal position, orientation, and morphology of the supernumerary teeth. Their effects on permanent incisors and the orthodontic treatment received by patients after the extraction of the supernumeraries were also investigated. Supernumerary teeth were most frequently observed in the central incisor region, in the palatal position, in the inverted orientation, and were most commonly conical in shape. The most common complication was median diastema, followed by displacement and delayed eruption of the adjacent incisors. Ten (71.4%) of the 14 odontomas showed delayed eruption of the adjacent incisors. Displacement of the incisors was more frequently observed in association with supernumerary teeth with tuberculate or supplemental shapes. Orthodontic traction was most frequently performed after the removal of odontomas. In 32 cases (13.3%), permanent incisors erupted after the orthodontic creation of sufficient space. Median diastema was most common complication. The delayed eruption of incisors was common in supernumerary teeth with a vertical orientation and an odontoma shape.

The effects of impacted premaxillary supernumerary teeth on permanent incisors

International Nuclear Information System (INIS)

Jung, Yun Hoa; Kim, Ji Yeon; Cho, Bong Hae

2016-01-01

The aim of this study was to examine the radiographic features associated with impacted premaxillary supernumerary teeth, to determine the relationship between their characteristics and their effects on permanent incisors, and to investigate the types of orthodontic treatment that patients received after the extraction of impacted supernumerary teeth. The clinical records and radiographs of 193 patients whose impacted premaxillary supernumerary teeth were removed were retrospectively reviewed, and 241 impacted supernumerary teeth were examined. Cone-beam computed tomographic images and panoramic radiographs were examined to determine the number, location, sagittal position, orientation, and morphology of the supernumerary teeth. Their effects on permanent incisors and the orthodontic treatment received by patients after the extraction of the supernumeraries were also investigated. Supernumerary teeth were most frequently observed in the central incisor region, in the palatal position, in the inverted orientation, and were most commonly conical in shape. The most common complication was median diastema, followed by displacement and delayed eruption of the adjacent incisors. Ten (71.4%) of the 14 odontomas showed delayed eruption of the adjacent incisors. Displacement of the incisors was more frequently observed in association with supernumerary teeth with tuberculate or supplemental shapes. Orthodontic traction was most frequently performed after the removal of odontomas. In 32 cases (13.3%), permanent incisors erupted after the orthodontic creation of sufficient space. Median diastema was most common complication. The delayed eruption of incisors was common in supernumerary teeth with a vertical orientation and an odontoma shape

Accuracy of three-dimensional printing for manufacturing replica teeth

OpenAIRE

Lee, Keun-Young; Cho, Jin-Woo; Chang, Na-Young; Chae, Jong-Moon; Kang, Kyung-Hwa; Kim, Sang-Cheol; Cho, Jin-Hyoung

2015-01-01

Objective Three-dimensional (3D) printing is a recent technological development that may play a significant role in orthodontic diagnosis and treatment. It can be used to fabricate skull models or study models, as well as to make replica teeth in autotransplantation or tooth impaction cases. The aim of this study was to evaluate the accuracy of fabrication of replica teeth made by two types of 3D printing technologies. Methods Fifty extracted molar teeth were selected as samples. They were sc...

In situ analysis of human teeth by external PIXE

Energy Technology Data Exchange (ETDEWEB)

Rautray, Tapash R., E-mail: tapash77@hotmail.co [Department of Dental Biomaterials, School of Dentistry, Kyungpook National University, 2-188-1 Samduk-dong, Jung-gu, Daegu (Korea, Republic of); ARASMIN, G. Udayagiri, Kandhamal, Orissa 762100 (India); Das, Saubhagyalaxmi [Institute of Physics, Sachivalaya Marg, Bhubaneswar 751005 (India); Rautray, Alekh C. [ARASMIN, G. Udayagiri, Kandhamal, Orissa 762100 (India)

2010-07-15

The elemental profiles of the enamel, cementum and caries of human teeth were analysed by the external proton induced X-ray emission studies. Ten elements namely P, Ca, V, Mn, Fe, Cu, Zn, As, Sr and Pb were estimated in the present study. P and Ca were found to be the major elements whereas all other elements were found in trace level. It was observed that the respective concentrations of elements namely P, Ca, Fe, Zn and Pb in enamel are more than those in cementum. Concentration of P ranged between 6.37% and 25% whereas Ca ranged between 12.94% and 43.36%.

Ancient pathogen DNA in human teeth and petrous bones

DEFF Research Database (Denmark)

Margaryan, Ashot; Hansen, Henrik B.; Rasmussen, Simon

2018-01-01

pestis. Based on shotgun sequencing data, four of these five plague victims showed clearly detectable levels of Y.pestis DNA in the teeth, whereas all the petrous bones failed to produce Y.pestis DNA above baseline levels. A broader comparative metagenomic analysis of teeth and petrous bones from 10...

Preservation of collagen and bioapatite fractions extracted from bison teeth in permafrost conditions

Energy Technology Data Exchange (ETDEWEB)

Cherkinsky, Alexander [Center for Applied Isotope Studies, University of Georgia, GA (United States); Glassburn, Crystal L. [Anthropology Department, University of Alaska, Fairbanks, AK (United States); Reuther, Joshua [Anthropology Department, University of Alaska, Fairbanks, AK (United States); University of Alaska, Museum of the North, Fairbanks, AK (United States)

2015-10-15

This research addresses the stability of bioapatite and collagen fractions of AMS dated steppe bison (Bison priscus) teeth. Through the course of other research, 8 prehistoric bison molars were submitted for AMS dating of fractions of collagen extracted from the dentine of each tooth. Because the teeth were well preserved and collagen yields were relatively high during the initial analysis, it provided an opportunity to further research differences between AMS dates produced on collagen from dentine and bioapatite fractions from enamel. The specimens were recovered from late Quaternary sediments of the Lost Chicken Creek drainage in east-central Alaska. All of the samples were very well preserved and gave high enough yield of carbon from both fractions. The {sup 14}C/{sup 13}C ratio was measured using 0.5 MV tandem AMS system. The {sup 14}C age of the samples varied across age ranges between 17,360 ± 50 and 43,370 ± 300 non-calibrated years BP. Such a wide range of ages allows us estimate the stability of each fraction in subarctic permafrost conditions. The results of analyses have shown that {sup 14}C ages of bioapatite fraction are rejuvenated as a result of isotopic exchange with the younger carbon from the soil solutions. The dating of bioapatite from the samples collected in the boreal climate of Alaska is possible only with a certain correction for the isotope fractionation.

Bacteroides gingivalis antigens and bone resorbing activity in root surface fractions of periodontally involved teeth

International Nuclear Information System (INIS)

Patters, M.R.; Landsberg, R.L.; Johansson, L.-A.; Trummel, C.L.; Robertson, P.R.

1982-01-01

Bone resorbing activity and the presence of antigens of Bacteroides gingivalis were assessed in plaque, calculus, cementum, and dentin obtained from roots of teeth previously exposed to periodontitis. Each fraction was obtained by scaling the root surface. The fraction were extracted by stirring and sonication, and the soluble centrifuged, sterilized, dialyzed, and adjusted to equivalent protein concentrations. Cementum and dentin extracts from impacted teeth were prepared similarly and served as controls. Stimulation of bone resorption by each extract was assessed in organ cultures of fetal rat bones by measurement of release of previously-incorporated 45 Ca from the bone into the medium. In some groups of teeth, calculus and cementum were treated with acid prior to scaling. Citric acid washes were recovered and dialyzed. An enzyme-linked immunosorbent assay (ELISA) was used to assess the extracts for the presence of antigens reactive with an antiserum to B. gingivalis. Significant stimulation of bone resorption was found in all calculus and periodontally-involved cementum preparations. ELISA showed significant levels of B.gingivalis antigens in plaque, calculus, and cementum of periodontally-involved teeth, but not in involved dentin nor in cementum or dentin of impact teeth. Treatment with citric acid removed essentially all B.gingivalis antigens from cementum but not calculus. The results suggest that substances which stimulate bone resorption and substances which react with B. gingivalis antiserum are present in surface plaque, calculus, and cementum or periodontally-involved teeth. These substances are not present in cementum and dentin of impacted teeth nor in dentin of periodontally-involved teeth. Treatment by both scaling and citric demineralization will remove most of these substances from cementum of teeth previously exposed to periodontitis. (author)

Bacteroides gingivalis antigens and bone resorbing activity in root surface fractions of periodontally involved teeth

Energy Technology Data Exchange (ETDEWEB)

Patters, M R; Landsberg, R L; Johansson, L A; Trummel, C L; Robertson, P R [Department of Periodontology, University of Connecticut, School of Dental Medicine, Farmington, Connecticut, U.S.A.

1982-01-01

Bone resorbing activity and the presence of antigens of Bacteroides gingivalis were assessed in plaque, calculus, cementum, and dentin obtained from roots of teeth previously exposed to periodontitis. Each fraction was obtained by scaling the root surface. The fraction were extracted by stirring and sonication, and the soluble centrifuged, sterilized, dialyzed, and adjusted to equivalent protein concentrations. Cementum and dentin extracts from impacted teeth were prepared similarly and served as controls. Stimulation of bone resorption by each extract was assessed in organ cultures of fetal rat bones by measurement of release of previously-incorporated /sup 45/Ca from the bone into the medium. In some groups of teeth, calculus and cementum were treated with acid prior to scaling. Citric acid washes were recovered and dialyzed. An enzyme-linked immunosorbent assay (ELISA) was used to assess the extracts for the presence of antigens reactive with an antiserum to B. gingivalis. Significant stimulation of bone resorption was found in all calculus and periodontally-involved cementum preparations. ELISA showed significant levels of B.gingivalis antigens in plaque, calculus, and cementum of periodontally-involved teeth, but not in involved dentin nor in cementum or dentin of impact teeth. Treatment with citric acid removed essentially all B.gingivalis antigens from cementum but not calculus. The results suggest that substances which stimulate bone resorption and substances which react with B. gingivalis antiserum are present in surface plaque, calculus, and cementum or periodontally-involved teeth. These substances are not present in cementum and dentin of impacted teeth nor in dentin of periodontally-involved teeth. Treatment by both scaling and citric demineralization will remove most of these substances from cementum of teeth previously exposed to periodontitis.

Designing protocols for the human teeth biobank of the Universidad Nacional de Colombia

Directory of Open Access Journals (Sweden)

Lina Constanza Gonzáles-Pita

2014-07-01

Full Text Available Protocols in a Tooth Bank are essential in order to assure smooth operation, reproducibility and standardization that minimize cross contamination, maintain original characteristics and physicochemical properties of teeth, fulll ethical and legal regulations and a proper disposal of residues. Objective: to propose the disinfection, storing and transportation protocols for the UNTB. Methods: A literature search was conducted using the words “teeth, human, tooth bank, disinfection, sterilization, storage, organization, biosecurity, biobank, protocol, prevention” in the Pubmed, Science Direct and Scielo databases. 37 papers ranging from 1988 up to 2014 were selected. International and Colombian ethical and legal regulations for organ donation, handling and investigation were taken into account as well as laboratory observations and chemical basic principles gained through several undergraduate and graduate thesis. All this input was carefully studied, analysed and critically modied for setting the recommended processes for the conversion of donated teeth into organs suitable for research. Results: Collection, transportation, cleaning/disinfection and storing protocols were planned and elaborated. Conclusions: Based on scientic literature, national and international regulations and experimental experience, several protocols for the UNTB were presented.

In vitro investigation of heat transfer phenomenon in human immature teeth.

Science.gov (United States)

Talebi, Maryam; Moghimi, Sahar; Shafagh, Mina; Kalani, Hadi; Mazhari, Fatemeh

2014-01-01

Background and aims. Heat generated within tooth during clinical dentistry can cause thermally induced damage to hard and soft components of the tooth (enamel, dentin and pulp). Geometrical characteristics of immature teeth are different from those of mature teeth. The purpose of this experimental and theoretical study was to investigate thermal changes in immature permanent teeth during the use of LED light-curing units (LCU). Materials and methods. This study was performed on the second mandibular premolars. This experimental investiga-tion was carried out for recording temperature variations of different sites of tooth and two dimensional finite element models were used for heat transfer phenomenon in immature teeth. Sensitivity analysis and local tests were included in the model validation phase. Results. Overall, thermal stimulation for 30 seconds with a low-intensity LED LCU increased the temperature from 28°C to 38°C in IIT (intact immature tooth) and PIT (cavity-prepared immature tooth). When a high-intensity LED LCU was used, tooth temperature increased from 28°C to 48°C. The results of the experimental tests and mathematical modeling illustrated that using LED LCU on immature teeth did not have any detrimental effect on the pulp temperature. Conclusion. Using LED LCU in immature teeth had no effect on pulp temperature in this study. Sensitivity analysis showed that variations of heat conductivity might affect heat transfer in immature teeth; therefore, further studies are required to determine thermal conductivity of immature teeth.

Type VII collagen is enriched in the enamel organic matrix associated with the dentin-enamel junction of mature human teeth.

Science.gov (United States)

McGuire, Jacob D; Walker, Mary P; Mousa, Ahmad; Wang, Yong; Gorski, Jeff P

2014-06-01

The inner enamel region of erupted teeth is known to exhibit higher fracture toughness and crack growth resistance than bulk phase enamel. However, an explanation for this behavior has been hampered by the lack of compositional information for the residual enamel organic matrix. Since enamel-forming ameloblasts are known to express type VII collagen and type VII collagen null mice display abnormal amelogenesis, the aim of this study was to determine whether type VII collagen is a component of the enamel organic matrix at the dentin-enamel junction (DEJ) of mature human teeth. Immunofluorescent confocal microscopy of demineralized tooth sections localized type VII collagen to the organic matrix surrounding individual enamel rods near the DEJ. Morphologically, immunoreactive type VII collagen helical-bundles resembled the gnarled-pattern of enamel rods detected by Coomassie Blue staining. Western blotting of whole crown or enamel matrix extracts also identified characteristic Mr=280 and 230 kDa type VII dimeric forms, which resolved into 75 and 25 kDa bands upon reduction. As expected, the collagenous domain of type VII collagen was resistant to pepsin digestion, but was susceptible to purified bacterial collagenase. These results demonstrate the inner enamel organic matrix in mature teeth contains macromolecular type VII collagen. Based on its physical association with the DEJ and its well-appreciated capacity to complex with other collagens, we hypothesize that enamel embedded type VII collagen fibrils may contribute not only to the structural resilience of enamel, but may also play a role in bonding enamel to dentin. Copyright © 2014 Elsevier Inc. All rights reserved.

Multiple congenitally missing teeth: treatment outcome with autologous transplantation and orthodontic space closure.

Science.gov (United States)

Fiorentino, Giuseppe; Vecchione, Pietro

2007-11-01

Treatment for patients with congenitally missing teeth can be challenging. The treatment options include retaining the deciduous teeth, extracting the deciduous teeth and allowing the space to close spontaneously, implant replacement, autotransplantation, prosthetic replacement, and orthodontic space closure. Autologous transplantation and space closure with orthodontic appliances are demonstrated in this case report.

Heavy metals in human teeth dentine: A bio-indicator of metals exposure and environmental pollution.

Science.gov (United States)

Asaduzzaman, Khandoker; Khandaker, Mayeen Uddin; Binti Baharudin, Nurul Atiqah; Amin, Yusoff Bin Mohd; Farook, Mohideen Salihu; Bradley, D A; Mahmoud, Okba

2017-06-01

With rapid urbanization and large-scale industrial activities, modern human populations are being increasingly subjected to chronic environmental heavy metal exposures. Elemental uptake in tooth dentine is a bioindicator, the uptake occurring during the formation and mineralization processes, stored to large extent over periods of many years. The uptake includes essential elements, most typically geogenic dietary sources, as well as non-essential elements arising through environmental insults. In this study, with the help of the Dental Faculty of the University of Malaya, a total of 50 separate human teeth were collected from dental patients of various ethnicity, age, gender, occupation, dietary habit, residency, etc. Analysis was conducted using inductively coupled plasma-mass spectrometry (ICP-MS), most samples indicating the presence of the following trace elements, placed in order of concentration, from least to greatest: As, Mn, Ba, Cu, Cr, Pb, Zn, Hg, Sb, Al, Sr, Sn. The concentrations have been observed to increase with age. Among the ethnic groups, the teeth of ethnic Chinese showed marginally greater metal concentrations than those of the Indians and Malays, the teeth dentine of females generally showing greater concentrations than that of males. Greater concentrations of Hg, Cu and Sn were found in molars while Pb, Sr, Sb and Zn were present in greater concentrations in incisors. With the elevated concentration levels of heavy metals in tooth dentine reflecting pollution from industrial emissions and urbanization, it is evident that human tooth dentine can provide chronological information on exposure, representing a reliable bio-indicator of environmental pollution. Copyright © 2017 Elsevier Ltd. All rights reserved.

Non-destructive, preclinical evaluation of root canal anatomy of human teeth with flat-panel detector volume CT (FD-VCT); Zerstoerungsfreie praeklinische Evaluation der Wurzelkanalanatomie menschlicher Zaehne mittels Flaechendetektor-Volumen-CT (FD-VCT)

Energy Technology Data Exchange (ETDEWEB)

Heidrich, G.; Hassepass, F.; Dullin, C.; Grabbe, E. [Universitaetsklinikum Goettingen, Abt. Diagnostische Radiologie (Germany); Attin, T.; Hannig, C. [Universitaetsklinikum Goettingen, Abt. fuer Zahnerhaltung, Praeventive Zahnheilkunde und Paradontologie (Germany)

2005-12-15

Purpose: Successful endodontic diagnostics and therapy call for adequate depiction of the root canal anatomy with multimodal diagnostic imaging. The aim of the present study is to evaluate visualization of the endodont with flat-panel detector volume CT (FD-VCT). Materials and methods: 13 human teeth were examined with the prototype of a FD-VCT. After data acquisition and generation of volume data sets in volume rendering technology (VRT), the findings obtained were compared to conventional X-rays and cross-section preparations of the teeth. Results: The anatomical structures of the endodont such as root canals, side canals and communications between different root canals as well as dentricles could be detected precisely with FD-VCT. The length of curved root canals was also determined accurately. The spatial resolution of the system is around 140 {mu}m. Only around 73% of the main root canals detected with FD-VCT and 87% of the roots could be visualized with conventional dental X-rays. None of the side canals, shown with FD-VCT, was detectable on conventional X-rays. In all cases the enamel and dentin of the teeth could be well delineated. No differences in image quality could be discerned between stored and freshly extracted teeth, or between primary and adult teeth. (orig.)

In Vitro Investigation of Heat Transfer Phenomenon in Human Immature Teeth

Directory of Open Access Journals (Sweden)

Maryam Talebi

2014-12-01

Full Text Available Background and aims. Heat generated within tooth during clinical dentistry can cause thermally induced damage to hard and soft components of the tooth (enamel, dentin and pulp. Geometrical characteristics of immature teeth are different from those of mature teeth. The purpose of this experimental and theoretical study was to investigate thermal changes in immature permanent teeth during the use of LED light-curing units (LCU. Materials and methods. This study was performed on the second mandibular premolars. This experimental investiga-tion was carried out for recording temperature variations of different sites of tooth and two dimensional finite element mod-els were used for heat transfer phenomenon in immature teeth. Sensitivity analysis and local tests were included in the mod-el validation phase. Results. Overall, thermal stimulation for 30 seconds with a low-intensity LED LCU increased the temperature from 28°C to 38°C in IIT (intact immature tooth and PIT (cavity-prepared immature tooth. When a high-intensity LED LCU was used, tooth temperature increased from 28°C to 48°C. The results of the experimental tests and mathematical modeling il-lustrated that using LED LCU on immature teeth did not have any detrimental effect on the pulp temperature. Conclusion. Using LED LCU in immature teeth had no effect on pulp temperature in this study. Sensitivity analysis showed that variations of heat conductivity might affect heat transfer in immature teeth; therefore, further studies are re-quired to determine thermal conductivity of immature teeth.

Effects of alternating and direct electrical current application on the odontoblastic layer in human teeth : an in vitro study

NARCIS (Netherlands)

Alwas-Danowska, HM; Huysmans, MCDNJM; Verdonschot, EH

Aim The aim of this study was to investigate the influence of a low intensity alternating current on the odontoblasts and odontoblast layer and compare this with the effects of a direct current. Methodology Teeth extracted for orthodontic were immersed in physiological saline stabilized with thymol

The effects of extraction of pulpally involved primary teeth on weight, height and BMI in underweight Filipino children: a cluster randomized clinical trial

NARCIS (Netherlands)

Monse, B.; Duijster, D.; Sheiham, A.; Grijalva-Eternod, C.S.; van Palenstein Helderman, W.H.; Hobdell, M.H.

2012-01-01

Background: Severe dental caries and the treatment thereof are reported to affect growth and well-being of young children. The objective of this study was to assess the effects of extraction of severely decayed pulpally involved primary teeth on weight and height in underweight preschool Filipino

Management of a rare case of idiopathic multiple unerupted impacted permanent teeth in an adult female patient

Directory of Open Access Journals (Sweden)

Karunakar Shetty

2016-01-01

Full Text Available This clinical case report describes the multi-disciplinary approach in the management of an unusual presentation of idiopathic multiple unerupted impacted permanent teeth in a 20-year-old female patient. The case was unique in that, not only were there multiple missing permanent teeth, but also over retained deciduous teeth and attrited existing permanent teeth with loss of vertical dimension of occlusion. Since the patient was young, it was decided to retain all the erupted permanent teeth and extract the infected deciduous teeth with the objective of fabricating overlay complete dentures. This is a simple, reversible and an economical treatment modality, which satisfies both the esthetic and functional demands where the extraction of teeth is not generally indicated and, in addition, provides a stable occlusion.

Gross, computed tomographic and histological findings in mandibular cheek teeth extracted from horses with clinical signs of pulpitis due to apical infection.

Science.gov (United States)

Casey, M B; Pearson, G R; Perkins, J D; Tremaine, W H

2015-09-01

The most prevalent type of equine dental pulpitis due to apical infection is not associated with coronal fractures or periodontal disease. The pathogenesis of this type of pulpitis is not fully understood. Computed tomography (CT) is increasingly used to investigate equine dental disorders. However, gross, tomographic and histopathological changes in equine dental pulpitis have not been compared previously. To compare gross, CT and histological appearances of sectioned mandibular cheek teeth extracted from horses with clinical signs of pulpitis without coronal fractures or periodontal disease. To contribute to understanding the pathogenesis of equine dental pulpitis. Descriptive study using diseased and healthy teeth. Mandibular cheek teeth extracted from horses with clinical signs of pulpitis (cases), and from cadavers with no history of dental disease (controls), were compared using CT in the transverse plane at 1 mm intervals. Teeth were then sectioned transversely, photographed and processed for histopathological examination. Tomographs were compared with corresponding gross and histological sections. Cement, dentine and bone had similar ranges of attenuation (550-2000 Hounsfield Units, HU) in tomographs but could be differentiated from pulp (-400 to 500 HU) and enamel (> 2500 HU). Twelve discrete dental lesions were identified grossly, 10 of which were characterised histologically. Reactive and reparative dentinogenesis and extensive pulpar mineralisation, previously undescribed, were identified. Pulpar oedema, neutrophilic inflammation, cement and enamel defects, and reactive cemental deposition were also observed. The CT and pathological findings corresponded well where there was mineralised tissue deposited, defects in mineralised tissue, or food material in the pulpar area. Pulpar and dentinal necrosis and cement destruction, evident grossly and histologically, did not correspond to CT changes. Computed tomography is useful for identifying deposition and

The length of teeth : A statistical analysis of the differences in length of human teeth for radiologic purposes

NARCIS (Netherlands)

Verhoeven, J.W.; Aken, J. van; Weerdt, G.P. van der

Intraoral radiograms can be made according to the long tube paralleling technique utilizing aiming devices. An important factor in the design of these instruments is the length of the teeth to be radiographed. Reliable data regarding the length of the teeth in the different regions of the mouth are

Elective extractions of first permanent molars: a review

Directory of Open Access Journals (Sweden)

Melike Kiraz

2018-05-01

Full Text Available Permanent first molar teeth possess a key role in the setting-up of the occlusion, contribute significantly to the chewing function and serve as a guide for other teeth. However, it is frequently encountered that permanent first molar teeth are extracted due to the predicted negative prognoses of caries or developmental defects. As a result of the uncontrolled extraction of the permanent first molar teeth during the growth and development period, drifting of adjacent teeth, continued eruption of the opposing teeth and displacements can be seen. Furthermore, following one-sided extraction, midline deviations, oppositional tooth eruption, skeletal and dental asymmetry, unilateral chewing habits, and temporo-mandibular joint disorders may occur. To prevent these pathological conditions and to maintain the stability of the occlusal relation, it is necessary to do compensation and balancing extractions of the permanent first molar teeth on the opposite/symmetric arc, assuming mesial drag of the permanent second and third molar teeth. With such controlled-extractions, especially in Class I cases, orthodontic or prosthetic treatments, which may require extra time, cost and effort, could be prevented and a conceivable occlusion can be established.

A new procedure for processing extracted teeth for immediate grafting in post-extraction sockets. An experimental study in American Fox Hound dogs.

Science.gov (United States)

Calvo-Guirado, José Luis; Cegarra Del Pino, Pilar; Sapoznikov, Lari; Delgado Ruiz, Rafael Arcesio; Fernández-Domínguez, Manuel; Gehrke, Sérgio Alexandre

2018-05-01

To investigate freshly extracted dental particulate used to graft post-extraction sockets in dogs, comparing new bone formation at experimental and control sites. Bilateral premolars P2, P3, P4 and first mandibular molars were extracted atraumatically from six American Fox Hound dogs. The teeth were ground immediately using a 'Smart Dentin Grinder'. The dentin particulate was sieved to ensure a grain size of 300-1200μm and immersed in an alcohol cleanser to dissolve organic debris and bacteria, followed by washing in sterile saline buffer solution. The animals were divided into two groups randomly: group 'A' (control) samples were left to heal without any extraction socket grafting procedure; group 'B' (experimental) sockets were filled with the autogenous dentin particulate graft. The rate of tissue healing and the quantity of bone formation were evaluated using histological and histomorphometric analyses at 60 and 90 days post-grafting. The type of bone generated was categorized as woven (immature bone) or lamellar bone (mature bone). Substantially more bone formation was found in Group B (experimental) than Group A (control) at 60 and 90 days (psocket preservation, protecting both buccal and lingual plates, generating large amounts of new woven bone formation after 60 days, and small amounts of lamellar bone after 90 days healing. Copyright © 2018 Elsevier GmbH. All rights reserved.

MULTIPLE RETAINED TEETH IN MANDIBLE: A Case Report

Directory of Open Access Journals (Sweden)

Cvetan Cvetanov

2010-07-01

Full Text Available Purpose: The aim of this science report is to show a rare case of multiple impacted teeth at adult patient and our propose clinical approach.Materials and methods: The clinical case is showed from adult man /64-year old/ with multiple impacted teeth (6 impacted teeth in the anterior place on the mandible were not suggestive of any syndrome or metabolic disorder. The extraction of the impacted teeth was made on two stage with piezosurgery unit under local anaesthesia. For prevention of postsurgical complications, as a swelling and prevention of postsurgical resorbtion were used coneshapes from pressure xeno colagen. To base on clinical and radiological examination we will discuss the differential diagnosis and we will offer a clinical approach about decided the case.Result and Conclusion: The incidence of multiple retained teeth by literature research range from 10.9% to 40.4%, most frequently is the retention of the third molars. In the literature most rarely have clinical reports about multiple retained teeth which differ from third molars at adult patients. The rare clinical case we showed is very demonstrative and the medicative approach which we used gave excellent result.

Application of PIGE to determine fluorine concentration in human teeth. Contribution to fluorosis study

International Nuclear Information System (INIS)

Salah, H.; Arab, N.

2007-01-01

Fluorosis, osteoselerosis, and systemic illness may result when tolerance levels of fluorine intake are exceeded. To avoid these abnormalities, we shall be aware of the mechanisms of their development. For this, quantitative results gathered from different parts of the world are necessary. In this paper, PIGE method is used to determine fluorine concentration in human teeth, collected from different regions of the Algerian Sahara. Both enamel and dentine regions were inspected. The external and internal mappings of the analyzed teeth have shown more variation in the localized fluorine concentration in dentine than in enamel, and the lowest level of fluorine concentration was observed in the frontier crown-root zone. The obtained results reveal relatively high fluorine concentration lying within the limit of fluorosis, according to the standardised grading dental fluorosis. (author)

In Vitro Investigation of Heat Transfer Phenomenon in Human Immature Teeth

OpenAIRE

Maryam Talebi; Sahar Moghimi; Mina Shafagh; Hadi Kalani; Fatemeh Mazhari

2014-01-01

Background and aims. Heat generated within tooth during clinical dentistry can cause thermally induced damage to hard and soft components of the tooth (enamel, dentin and pulp). Geometrical characteristics of immature teeth are different from those of mature teeth. The purpose of this experimental and theoretical study was to investigate thermal changes in immature permanent teeth during the use of LED light-curing units (LCU). Materials and methods. This study was performed on the second ...

Discrimination between intact and decayed pulp regions in carious teeth by ADC mapping.

Science.gov (United States)

Cankar, Ksenija; Nemeth, Lidija; Bajd, Franci; Vidmar, Jernej; Serša, Igor

2014-01-01

The aim of this study was to evaluate an advanced magnetic resonance imaging (MRI) method, apparent diffusion coefficient (ADC) mapping, in the functional assessment of carious teeth. 38 extracted human teeth with scores of 0, 3 and 6 according to International Caries Detection and Assessment System (ICDAS) criteria were screened and subsequently analyzed by MRI at 2.35 T. Histology sectioning of teeth was used for the gold standard by analyzing two extreme cases (intact and severely decayed). ADC maps of the same teeth were calculated from corresponding diffusion-weighted images and used to obtain ADC distributions along dental pulp as functions of the relative pulp length measured from the occlusal pulp side. The measured distributions were analyzed for the best fit by a four-parameter three-segment linear regression model for ADC distribution along the pulp. MRI results were in good agreement with findings in histological sections of identical teeth. The best fit model parameters, relative decayed region depth, relative transition region width and ADC values of intact and decayed pulp tissue, showed statistically significant differences between the ADC values of intact and decayed pulp tissue (1.0 × 10(-9) m(2)/s vs. 0.74-0.89 × 10(-9) m(2)/s) and the relative decayed region depth progressing with ICDAS score (3 vs. 46% with ICDAS 3 vs. ICDAS 6). The results of this feasibility study confirmed relevance of ADC mapping for the discrimination and localization of intact and decayed regions in dental pulps of carious teeth. © 2014 S. Karger AG, Basel.

Do the levels of selected metals differ significantly between the roots of carious and non-carious teeth?

International Nuclear Information System (INIS)

Malara, Piotr; Kwapulinski, Jerzy; Malara, Beata

2006-01-01

Since the metals deposited in teeth during formation and mineralization processes are to a large extent retained, human teeth receive a considerable attention as the indicators of the heavy metal exposure. The use of permanent teeth is limited because the extraction of healthy permanent teeth just for this purpose is hardly acceptable. As the issue of the loss of elements from a carious lesion in the coronal part of a tooth remains controversial, the valuable material could only be the root of carious and fractured permanent teeth. However, to ensure the validity of the results, it should be ascertained that the levels of certain toxic and essential elements do not differ significantly between the roots of non-carious and carious teeth, and therefore this is the aim of this project. The levels of cadmium, chromium, copper, iron, manganese, lead, zinc, potassium, sodium, calcium and magnesium were determined in the roots of 344 permanent teeth (189 carious and 155 caries-free teeth) from the residents of Ruda Slaska, Poland, aged 18 to 34. No statistically significant difference between the concentration of these metals in the roots of non-carious and carious teeth was found. This finding applies to both the general population and after the grouping by donor's gender and tooth type. The concentration of lead, iron, calcium and manganese in the roots of non-carious and carious teeth exhibited dependence upon tooth type, as well as the concentration of potassium in the roots of carious teeth. Since the mineral composition of the roots of permanent teeth is similar for the non-carious, as well as the carious teeth, they can be indiscriminately selected for the tests required by a research project, as they will produce the comparable results. However, in the case of lead, iron, calcium, potassium and manganese, the comparison should be made after grouping by tooth type

Natural tooth pontic with splinting of periodontally weakened teeth using fiber-reinforced composite resin

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Gauri Srinidhi

2014-01-01

Full Text Available Replacement of missing anterior teeth due to periodontal reasons is challenging due to the poor support of abutment teeth. This prevents the use of fixed partial dentures (FPDs. Fiber-reinforced splinting provides a viable alternative to the dentist while choosing a treatment plan in replacing missing anterior teeth in periodontally compromised patients as opposed to conventional modalities like FPDs or removable partial dentures. Replacing missing teeth using either patient′s own tooth or a denture tooth as pontic can be done by splinting adjacent teeth with fiber reinforced composite. The splinting has an additional advantage of stabilizing adjacent mobile teeth. This case report details the case selection, procedure with follow-up of a case where the natural extracted tooth of the patient was used as pontic to replace a missing anterior tooth. The splinting was done with fiber reinforced composite resin. Fiber-reinforced composite resin splinting of patient′s extracted natural tooth is economical, fast, and easy to use chairside technique with the added benefit of periodontal stabilization.

Hidden contributions of the enamel rods on the fracture resistance of human teeth.

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Yahyazadehfar, M; Bajaj, Devendra; Arola, Dwayne D

2013-01-01

The enamel of human teeth is generally regarded as a brittle material with low fracture toughness. Consequently, the contributions of this tissue in resisting tooth fracture and the importance of its complex microstructure have been largely overlooked. In this study an experimental evaluation of the crack growth resistance of human enamel was conducted to characterize the role of rod (i.e. prism) orientation and degree of decussation on the fracture behavior of this tissue. Incremental crack growth was achieved in-plane, with the rods in directions longitudinal or transverse to their axes. Results showed that the fracture resistance of enamel is both inhomogeneous and spatially anisotropic. Cracks extending transverse to the rods in the outer enamel undergo a lower rise in toughness with extension, and achieve significantly lower fracture resistance than in the longitudinal direction. Though cracks initiating at the surface of teeth may begin extension towards the dentin-enamel junction, they are deflected by the decussated rods and continue growth about the tooth's periphery, transverse to the rods in the outer enamel. This process facilitates dissipation of fracture energy and averts cracks from extending towards the dentin and vital pulp. Copyright © 2012 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Clinical evaluation of postradiation dental extraction

International Nuclear Information System (INIS)

Kusukawa, Jingo; Ohisi, Shinichiro; Kameyama, Tadamitsu; Yoshizumi, Munehiro; Hayabuchi, Naofumi

1996-01-01

Twenty-one patients who had undergone postradiation dental extraction were evaluated clinically. All patients had received irradiation for primary head and neck malignancies at doses ranging from 8 to 60 Gy (mean, 51.6 Gy). Time to dental extraction after irradiation ranged from 8 to 156 months (mean, 57.9 months). Of the 21 patients (80 teeth extracted, including 33 maxillary teeth and 47 mandibular teeth), one had delayed healing after wisdom tooth extraction due to postextraction irradiation. Thus, osteoradionecrosis after dental extraction did not develop. These results suggest that dental extraction after radiation is not contraindicated. To prevent complications, patients who have received radiation and require extractions should be cared for by oral and maxillofacial surgeons in close association with radiation oncologists. (author)

Periodontal Reasons for Tooth Extraction in a Group of Greek Army Personnel

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Nikolaos Andreas Chrysanthakopoulos

2011-06-01

Full Text Available Background and aims. The aim of this study was to investigate the prevalence of permanent teeth extracted due to periodontal disease and its relation to age, military rank, and type of extracted teeth due to periodontal and non-periodontal reasons among a group of Greek Army personnel attending a military dental practice. Materials and methods. Study population consisted of 509 officers, non-commissioned officers and soldiers, aged 18 to 44 years from a military dental hospital in Greece. The reasons for extractions of teeth for a period of two years were obtained, including aspects such as age, military rank and the type of teeth extracted due to periodontal and non-periodontal reasons. Data were analyzed using chi-squared test. Results. The total number of extracted teeth was 1,231, of which 34.4% were extracted because of periodontal reasons, 32.2% for dental caries and 33.4% for other reasons. The average number of extracted teeth due to periodontal disease showed an increase with age. Maxillary and mandibular first and second molars were the most frequently extracted teeth due to periodontal reasons; however, the anterior teeth of both jaws with mobility (grade III, the same teeth with attachment loss (≥5.0 mm and the posterior teeth of both jaws with furcation involvement (grade IV were the most frequently extracted teeth due to periodontal reasons. Conclusion. Although the goal of the WHO regarding the reduction of dental caries was accomplished, periodontal disease was still the main cause of tooth extraction and showed an increase with age.

Effectiveness of gaseous and intravenous inductions on children′s anxiety and distress during extraction of teeth under general anesthesia

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Giath Gazal

2015-01-01

Full Text Available Context: Anxiety and distress regarding dental treatment is a major issue for dental patients and can be exaggerated in pediatric dental patients. Aims: The aim was to investigate how different methods of induction for general anesthesia affect children′s distress for dental procedures such as extraction of teeth. Subjects and Methods: This was an observational clinical study conducted at Manchester University Dental Hospital. The induction of anesthesia in children was achieved with either intravenous (I.V. or a gaseous induction. The Modified Child Smiley Faces Scales were completed for children at various times intervals. Statistical Analysis Used: There were statistically significant differences between the mean distress scores for the I.V. and inhalation groups (P values from independent t-test: P < 0.001 was applied. Results: In gaseous induction group, the number of children who scored severe and very severe distress was greater than those who were in I.V. group. Gaseous induction was used for 23 children. Preoperatively, 56.5% children were in very severe distress, 17.4% in severe distress, 13% in moderate distress, 8.7% in mild distress and only one (4.3% showed no distress. For I.V. induction, 11.2% children were in very severe distress, 9% in severe distress, and 9.6% in moderate distress, 24.2% in mild distress and 46.1% showed no distress. Conclusions: Gaseous induction anesthesia for extractions of teeth does produce high levels of distress than I.V. induction in children for dental extractions. There was no significant difference between both induction methods in terms of distress levels at the time of recovery and 15 min postoperatively.

Study of the temporal evolution of Whitening Teeth immersed in Peroxide of hydrogen (H2O2) Using Digital Image Processing

International Nuclear Information System (INIS)

Díaz, L; Morales, Y; Torres, C

2015-01-01

The esthetic dentistry reference in our society is determined by several factors, including one that produces more dissatisfaction is abnormal tooth color or that does not meet the patient's expectations. For this reason it has been designed and implemented an algorithm in MATLAB that captures, digitizes, pre-processing and analyzed dental imaging by allowing to evaluate the degree of bleaching caused by the use of peroxide of hidrogen. The samples analyzed were human teeth extracted, which were subjected to different concentrations of peroxide of hidrogen and see if they can teeth whitening when using these products, was used different concentrations and intervals of time to analysis or study of the whitening of the teeth with the hydrogen peroxide

About Kids' Teeth

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... wear a mouthguard when playing sports like basketball, soccer, football and hockey. 17 – 21 Years Old The last teeth to appear are wisdom teeth at around ages 17 – 21. By age 21, all 32 of the adult teeth have usually appeared. Learn about Nutrition Baby Teething Baby Teeth and Teething Baby teeth ...

Strontium-90 concentrations in human teeth in South Ukraine, 5 years after the Chernobyl accident

International Nuclear Information System (INIS)

Kulev, Y.D.; Polikarpov, G.G.; Prigodey, E.V.; Assimakopoulos, P.A.

1994-01-01

Approximately 1000 human teeth, collected in South Ukraine, in 1990-1991, were measured for 90 Sr concentration. The teeth were grouped into 18 samples according to the age and sex of the donors. Measured levels of 90 Sr concentrations were lower by a factor of 10 than measurements taken in the mid-1960s and mid-1970s. An interesting feature of the data is a 3-fold enhancement of contamination levels in the 25-45 year-old age group of the male population. A possible explanation for this anomaly is that this age group contains a significant number of men who were mobilized immediately after the Chernobyl accident for clean-up operations within the 30-km zone around the damaged nuclear power plant

AMS-14C analysis of modern teeth: A comparison between two sample preparation techniques

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Solis, C.; Solis-Meza, E.; Morales, M. E.; Rodriguez-Ceja, M.; Martínez-Carrillo, M. A.; Garcia-Calderon, D.; Huerta, A.; Chávez, E.

2017-09-01

AMS-14C analysis of modern teeth has become important for forensic studies. 14C content in human teeth reflects the 14C atmospheric concentration during its formation and allows the calculation of the actual year of birth. Through AMS, it is possible to measure the 14C concentrations in a tissue with high precision. However, there is a debate about which should be the best fraction for teeth carbon dating: collagen or enamel. This work focuses on the results obtained from enamel and collagen extracted from Mexican people in order to compare them. Collagen from dental pieces donated from people older than 60-years-old have been included to understand the turnover process and usefulness of collagen to determine the date of birth. Our results indicate that when a single dental piece is available, enamel method allows the determination of the tooth formation date. Dating collagen of the same tooth helps to discriminate if the formation date belongs to the left or the right side of the peak bomb, but also corroborates, the ages obtained through enamel analysis.

Distinctive genetic activity pattern of the human dental pulp between deciduous and permanent teeth.

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Ji-Hee Kim

Full Text Available Human deciduous and permanent teeth exhibit different developmental processes, morphologies, histological characteristics and life cycles. In addition, their pulp tissues react differently to external stimuli, such as the pulp sensitivity test, dental trauma and pulp therapy materials. These suggest differences in gene expression and regulation, and in this study we compared gene-expression profiles of the human dental pulp from deciduous and permanent teeth. Pulp tissues from permanent premolars and deciduous molars aged 11-14 years were extirpated and mRNA was isolated for cDNA microarray analysis, and quantitative real-time PCR (qPCR. Other teeth were used for immunohistochemical analysis (IHC. Microarray analysis identified 263 genes with a twofold or greater difference in expression level between the two types of pulp tissue, 43 and 220 of which were more abundant in deciduous and permanent pulp tissues, respectively. qPCR analysis was conducted for eight randomly selected genes, and the findings were consistent with the cDNA microarray results. IHC confirmed that insulin-like growth factor 2 mRNA-binding protein 1 (IGF2BP1 was broadly expressed in deciduous dental pulp tissue, but minimally expressed in permanent dental pulp tissue. Immunohistochemical analysis showed that calbindin 1 (CALB1, leucine-rich repeat-containing G-protein-coupled receptor 5 (LGR5, and gamma-aminobutyric acid A receptor beta 1 (GABRB1 were abundantly expressed in permanent predentin/odontoblasts, but only minimally expressed in deciduous dental pulp tissue. These results show that deciduous and permanent pulp tissues have different characteristics and gene expression, suggesting that they may have different functions and responses to therapies focused on pulp or dentin regeneration.

Distinctive genetic activity pattern of the human dental pulp between deciduous and permanent teeth.

Science.gov (United States)

Kim, Ji-Hee; Jeon, Mijeong; Song, Je-Seon; Lee, Jae-Ho; Choi, Byung-Jai; Jung, Han-Sung; Moon, Seok Jun; DenBesten, Pamela K; Kim, Seong-Oh

2014-01-01

Human deciduous and permanent teeth exhibit different developmental processes, morphologies, histological characteristics and life cycles. In addition, their pulp tissues react differently to external stimuli, such as the pulp sensitivity test, dental trauma and pulp therapy materials. These suggest differences in gene expression and regulation, and in this study we compared gene-expression profiles of the human dental pulp from deciduous and permanent teeth. Pulp tissues from permanent premolars and deciduous molars aged 11-14 years were extirpated and mRNA was isolated for cDNA microarray analysis, and quantitative real-time PCR (qPCR). Other teeth were used for immunohistochemical analysis (IHC). Microarray analysis identified 263 genes with a twofold or greater difference in expression level between the two types of pulp tissue, 43 and 220 of which were more abundant in deciduous and permanent pulp tissues, respectively. qPCR analysis was conducted for eight randomly selected genes, and the findings were consistent with the cDNA microarray results. IHC confirmed that insulin-like growth factor 2 mRNA-binding protein 1 (IGF2BP1) was broadly expressed in deciduous dental pulp tissue, but minimally expressed in permanent dental pulp tissue. Immunohistochemical analysis showed that calbindin 1 (CALB1), leucine-rich repeat-containing G-protein-coupled receptor 5 (LGR5), and gamma-aminobutyric acid A receptor beta 1 (GABRB1) were abundantly expressed in permanent predentin/odontoblasts, but only minimally expressed in deciduous dental pulp tissue. These results show that deciduous and permanent pulp tissues have different characteristics and gene expression, suggesting that they may have different functions and responses to therapies focused on pulp or dentin regeneration.

Root resorption of endodontically treated teeth following orthodontic treatment: a meta-analysis.

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Ioannidou-Marathiotou, Ioulia; Zafeiriadis, Anastasios A; Papadopoulos, Moschos A

2013-09-01

The aim of this meta-analysis was to investigate the effect of orthodontic treatment on root resorption of endodontically treated teeth compared to vital teeth. A literature search was conducted in 18 electronic databases. Review articles and relevant articles were searched for cross-references. Two independent reviewers screened all articles according to predefined inclusion and exclusion criteria and extracted the corresponding data. The pooled estimate of mean difference of root resorption weighted by the fixed-effect model and the corresponding 95 % confidence intervals (CIs) were used to construct a forest plot by implementing the "RevMan 5.1" software. Quality and heterogeneity assessments as well as publication bias evaluation and sensitivity analyses were performed. Inter-reviewer agreement for data selection, data extraction and quality analysis was evaluated by Cohen's kappa. Six out of 1,942 original papers met the inclusion criteria. Four out of six studies were included in the quantitative analysis. Root resorption was less in endodontically treated teeth than in vital teeth (MD = -0.48 mm; 95 % CI = -0.81 to -0.14 mm). The funnel plot indicated no evidence of publication bias, while no data heterogeneity was present (I(2) = 0 %). However, the overall quality of the included studies was considered as "low." Following orthodontic treatment, endodontically treated teeth exhibit relatively less root resorption than teeth with vital pulps. Clinicians should consider orthodontic movement of endodontically treated teeth as a relatively safe clinical procedure.

Improvement in properties of plastic teeth by electron beam irradiation

International Nuclear Information System (INIS)

Sano, Yuko; Ishikawa, Shun-ichi; Seguchi, Tadao

2011-01-01

Improvement of the comfort and esthetics of artificial plastic teeth is desirable for the recently increasing numbers of elderly in society. Plastic teeth made of polycarbonate (PC) were modified by electron beam (EB) irradiation under specific conditions, and the change in the chemical properties of the PC was investigated. The water absorption, glucose attachment, level of bis-phenol-A (BPA) extraction, maltose adhesion, and mucin adhesion on the PC teeth were measured before and after EB irradiation. EB irradiation to a dose of 3.5 kGy at 150 o C in a nitrogen gas atmosphere reduced the water absorption by 20%, glucose absorption by 40%, maltose adhesion by 20%, and the amount of various amino acids, formed as the hydrolysis products of mucin, adhering on the PC teeth were reduced by 60-99%. The BPA content was lower than the detection limit for analysis of both the original and the EB irradiated PC teeth. - Highlights: → Radiation improvement of polycarbonate for plastic teeth by EB irradiation 3.5 kGy at 150 o C in inert gas. → Water and glucose absorption and maltose adhesion on PC teeth were much reduced. → Bis-phenol-A content from PC teeth was lower than the detection limit after irradiation.

Clinical parameter of odontoma with special emphasis on treatment of impacted teeth-a retrospective multicentre study and literature review.

Science.gov (United States)

Kämmerer, Peer W; Schneider, Daniel; Schiegnitz, Eik; Schneider, Sarah; Walter, Christian; Frerich, Bernhard; Kunkel, Martin

2016-09-01

Odontoma-separated into complex (CxOD) and compound (CpOD) subtypes-represents the most frequent odontogenic malformation. Retention of permanent teeth is a common symptom. Therefore, in a series of odontomas, an analysis of the management of retained teeth was conducted. In a retrospective multicenter study of two University Medical Centers and one private praxis in Germany, demographic and clinical data regarding odontomas from 01/2000-03/2015 were obtained. In particular, the influence of operative therapy on the dentition and on the treatment of impacted teeth was analyzed. Forty-five patients with 15 CxOD and 30 CpOD were included. Initial symptoms were delayed eruption of permanent teeth (n = 11), pain (n = 4), and swellings (n = 2); 28 cases were discovered by incidence, all of them via panoramic radiographs. The mandible/maxilla ratio was about 1:0.55 (29/16). Thirty-five out of 45 odontomas were in close proximity of at least one tooth (n = 16 at molars). A total of 14 teeth were extracted (CxOD: n = 5; CpOD: n = 9). Extractions had to be conducted more often in older patients (mean age 39.8 vs. 25.6 years). Of the non-extracted teeth, 8 teeth were displaced and retained. Of those, 4 teeth were aligned in the dental arch via orthodontic help and 2 teeth erupted spontaneously after operation during the follow-up period. In all cases, no relapse was seen. Odontomas can cause displacement as well as malformation and resorption of the adjacent teeth. Mostly, removal of odontomas is conducted. Extirpation of odontoma can allow for normal tooth eruption, often rendering extractions avoidable. Orthodontic alignment, though sometimes challenging, is a reasonable therapeutic option. These findings underline the value of the panoramic radiograph in preventive dentistry in younger patients.

Spectrophotometric Evaluation of the Pulpal Peroxide Levels in Intact and Restored Teeth - An Invitro Study.

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Patri, Gaurav; Acharya, Gourismita; Agrawal, Pratik; Panda, Vijeta

2016-08-01

Hydrogen peroxide (30%) is a commonly used "in office" bleaching agent. Deleterious effects of hydrogen peroxide on the pulp have been observed. The present study was conducted with the aim to evaluate the penetration of 30% hydrogen peroxide into the pulp chamber through intact teeth and through the surface of teeth, restored with either hybrid composite or Resin Modified Glass Ionomer Cement (RMGIC). Sixty extracted human maxillary central incisors were selected and divided into six groups. Two groups were restored with hybrid composite resin and two with RMGIC, while two groups were left intact. The teeth with acetate buffer solution in their pulp cavity were then immersed in either 30% hydrogen peroxide or distilled water depending upon the group, for 60 minutes at 37°C. Then horseradish peroxidase and leucocrystal violet were added to the acetate buffer solution present in the pulp chamber after it was transferred to a test tube and the optical density of the resultant blue solution obtained was measured spectrophotometrically. The data obtained were analyzed using one way ANOVA and Student's t-test. The data obtained established that hydrogen peroxide penetrated into the pulp from the bleaching agent used. Hydrogen peroxide (30%) showed the highest pulpal peroxide level in teeth restored with RMGIC followed by teeth restored with hybrid composite resin and the least amount of penetration was observed in intact teeth. The amount of peroxide penetration into the tooth is more through restored tooth than intact tooth and is also dependant on the type of restorative materials used.

An exploratory study of human teeth enamel by using Ft-Raman spectroscopy

International Nuclear Information System (INIS)

Afishah Alias; Siti Rahayu Mohd Hashim; Mihaly, Judith; Julyannie Wajir; Fauziah Abdul Aziz

2009-01-01

Unaffected , affected and heavily affected teeth enamel were studied by using FT-Raman spectroscopy. The 14 permanent teeths enamel surface were measured randomly, resulting in total n = 43 FT-Raman spectra. The results obtained from FT-Raman spectra of heavily affected, affected and unaffected tooths enamel surfaces did not show any significant difference. In this study, Kruskal-Wallis and Wilcoxon rank sum tests were used to compare the intensity between the categories of enamel as well as the surfaces of teeth samples. (author)

Investigation of human teeth with respect to the photon interaction, energy absorption and buildup factor

Energy Technology Data Exchange (ETDEWEB)

Kurudirek, Murat, E-mail: mkurudirek@gmail.co [Faculty of Science, Department of Physics, Ataturk University, 25240 Erzurum (Turkey); Topcuoglu, Sinan [Faculty of Dentistry, Department of Endodontic, Ataturk University, 25240 Erzurum (Turkey)

2011-05-15

The effective atomic numbers and electron densities of human teeth have been calculated for total photon interaction (Z{sub PI{sub e{sub f{sub f}}}},Ne{sub PI{sub e{sub f{sub f}}}}) and photon energy absorption (Z{sub PEA{sub e{sub f{sub f}}}},Z{sub RW{sub e{sub f{sub f}}}}Ne{sub PEA{sub e{sub f{sub f}}}}) in the energy region 1 keV-20 MeV. Besides, the energy absorption (EABF) and exposure (EBF) buildup factors have been calculated for these samples by using the geometric progression fitting approximation in the energy region 0.015-15 MeV up to 40 mfp (mean free path). Wherever possible the results were compared with experiment. Effective atomic numbers (Z{sub PI{sub e{sub f{sub f}}}}) of human teeth were calculated using different methods. Discrepancies were noted in Z{sub PI{sub e{sub f{sub f}}}} between the direct and interpolation methods in the low and high energy regions where absorption processes dominate while good agreement was observed in intermediate energy region where Compton scattering dominates. Significant variations up to 22% were observed between Z{sub PI{sub e{sub f{sub f}}}} and Z{sub PEA{sub e{sub f{sub f}}}} in the energy region 30-150 keV which is the used energy range in dental cone beam computed tomography (CBCT) X-ray machines. The Z{sub eff} values of human teeth were found to relatively vary within 1% if different laser treatments are applied. In this variation, the Er:YAG laser treated samples were found to be less effected than Nd:YAG laser treated ones when compared with control group. Relative differences between EABF and EBF were found to be significantly high in the energy region 60 keV-1 MeV even though they have similar variations with respect to the different parameters viz. photon energy, penetration depth.

Comparative study of nanomechanical properties of cements used in teeth restoration

International Nuclear Information System (INIS)

Peluccio, M S; Bignardi, C; Lombardo, S; Montevecchi, F M; Carossa, S

2007-01-01

The discipline of dental science includes the diagnosis of disease in the mouth and teeth, its manifestations and the procedures involved in the restoration of their integrity and function. Restoration of lost tooth structure with suitable materials plays an integral part in the successful rehabilitation of oral tissues. Several factors influence the performance of dental restorations. These factors include the type of cement used to bond crown restoration to prepared teeth. The nanoindentation method was used to explore the mechanical properties of different types of resin cement polymerized using different techniques. A Nano Indenter XP (from MTS Nano Instruments, USA) was used for the experimental tests. A sample of 40 extracted human teeth were restored using two different resin cements: Variolink II (Ivoclar Vivadent, Liechtenstein) and Venus A2 (Heraeus Kulzer, Germany). Both resin cements are light-cured and one of them is self-cured so that the degree of polymerization would be higher. The data obtained for nanohardness and the Young's modulus were analysed using ANOVA to evaluate the influence of different factors (the resin cement and polymerization technique used, the position on the tooth-restoration interface) and to determine the best performance for restoration. The results obtained could give a useful indication of the choice of cementation technique and of the materials used for the restoration of lost tooth structure in different clinical cases

Segmentation of teeth in CT volumetric dataset by panoramic projection and variational level set

Energy Technology Data Exchange (ETDEWEB)

Hosntalab, Mohammad [Islamic Azad University, Faculty of Engineering, Science and Research Branch, Tehran (Iran); Aghaeizadeh Zoroofi, Reza [University of Tehran, Control and Intelligent Processing Center of Excellence, School of Electrical and Computer Engineering, College of Engineering, Tehran (Iran); Abbaspour Tehrani-Fard, Ali [Islamic Azad University, Faculty of Engineering, Science and Research Branch, Tehran (Iran); Sharif University of Technology, Department of Electrical Engineering, Tehran (Iran); Shirani, Gholamreza [Faculty of Dentistry Medical Science of Tehran University, Oral and Maxillofacial Surgery Department, Tehran (Iran)

2008-09-15

Quantification of teeth is of clinical importance for various computer assisted procedures such as dental implant, orthodontic planning, face, jaw and cosmetic surgeries. In this regard, segmentation is a major step. In this paper, we propose a method for segmentation of teeth in volumetric computed tomography (CT) data using panoramic re-sampling of the dataset in the coronal view and variational level set. The proposed method consists of five steps as follows: first, we extract a mask in a CT images using Otsu thresholding. Second, the teeth are segmented from other bony tissues by utilizing anatomical knowledge of teeth in the jaws. Third, the proposed method is followed by estimating the arc of the upper and lower jaws and panoramic re-sampling of the dataset. Separation of upper and lower jaws and initial segmentation of teeth are performed by employing the horizontal and vertical projections of the panoramic dataset, respectively. Based the above mentioned procedures an initial mask for each tooth is obtained. Finally, we utilize the initial mask of teeth and apply a Variational level set to refine initial teeth boundaries to final contours. The proposed algorithm was evaluated in the presence of 30 multi-slice CT datasets including 3,600 images. Experimental results reveal the effectiveness of the proposed method. In the proposed algorithm, the variational level set technique was utilized to trace the contour of the teeth. In view of the fact that, this technique is based on the characteristic of the overall region of the teeth image, it is possible to extract a very smooth and accurate tooth contour using this technique. In the presence of the available datasets, the proposed technique was successful in teeth segmentation compared to previous techniques. (orig.)

Segmentation of teeth in CT volumetric dataset by panoramic projection and variational level set

International Nuclear Information System (INIS)

Hosntalab, Mohammad; Aghaeizadeh Zoroofi, Reza; Abbaspour Tehrani-Fard, Ali; Shirani, Gholamreza

2008-01-01

Quantification of teeth is of clinical importance for various computer assisted procedures such as dental implant, orthodontic planning, face, jaw and cosmetic surgeries. In this regard, segmentation is a major step. In this paper, we propose a method for segmentation of teeth in volumetric computed tomography (CT) data using panoramic re-sampling of the dataset in the coronal view and variational level set. The proposed method consists of five steps as follows: first, we extract a mask in a CT images using Otsu thresholding. Second, the teeth are segmented from other bony tissues by utilizing anatomical knowledge of teeth in the jaws. Third, the proposed method is followed by estimating the arc of the upper and lower jaws and panoramic re-sampling of the dataset. Separation of upper and lower jaws and initial segmentation of teeth are performed by employing the horizontal and vertical projections of the panoramic dataset, respectively. Based the above mentioned procedures an initial mask for each tooth is obtained. Finally, we utilize the initial mask of teeth and apply a Variational level set to refine initial teeth boundaries to final contours. The proposed algorithm was evaluated in the presence of 30 multi-slice CT datasets including 3,600 images. Experimental results reveal the effectiveness of the proposed method. In the proposed algorithm, the variational level set technique was utilized to trace the contour of the teeth. In view of the fact that, this technique is based on the characteristic of the overall region of the teeth image, it is possible to extract a very smooth and accurate tooth contour using this technique. In the presence of the available datasets, the proposed technique was successful in teeth segmentation compared to previous techniques. (orig.)

Electron spin resonance dating of human teeth from Toca da Santa shelter of São Raimundo Nonato, Piauí, Brazil

Science.gov (United States)

Kinoshita, A.; Figueiredo, A. M. G.; Felice, G. D.; Lage, M. C. S. M.; Guidon, N.; Baffa, O.

2008-02-01

Results of the dating of fossil human teeth excavated from a shelter in the surroundings areas of the Serra da Capivara National Park, São Raimundo Nonato, Piauí, Brazil are presented. This shelter was partially excavated to search for more data that could improve the archaeological context of the Garrincho’s limestone hill sites, where the Toca do Gordo do Garrincho shelter provided two human teeth dated by conventional C-14 in (12,170 ± 40) yBP (years before present) and calibrated age (2 Sigma, 95% probability) 15,245 14,690 yBP (Beta 136204) [E. Peyre, C. Guérin, N. Guidon, I. Coppens, CR Acad. Sci. Paris, Sciences de la terre et des planètes/ Earth & Planetary Sciences 327 (1998) 335, [1

Interdisciplinary treatment of a patient with multiple missing teeth and periodontitis.

Science.gov (United States)

Ahn, Jae-Chan; Lee, Jae-Hong; Yoon, Joon-Ho; Lee, Ji-Yeon; Kim, Jung-Hoon

2018-02-01

A 49-year-old woman with several missing and periodontically compromised teeth was referred to the orthodontic department of National Health Insurance Service Ilsan Hospital by the periodontic department for interdisciplinary treatment. Multiple posterior teeth had been extracted 10 days earlier. Her chief complaint was crowding of the anterior teeth, and she wanted to improve both esthetics and function. Orthodontic, periodontic, and prosthodontic treatments were undertaken in the proper timing and sequence with an interdisciplinary approach. As a result, improved periodontal health and a stable occlusion and vertical dimension were achieved. Although there were limited teeth and alveolar bone for anchorage, good esthetic and functional treatment results were obtained through the application of temporary anchorage devices and proper biomechanics. Copyright © 2017 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.

Overdentures on natural teeth: a new approach.

Science.gov (United States)

Previgliano, V; Barone Monfrin, S; Santià, G; Preti, G

2004-01-01

The study presents a new type of copings for overdentures on natural teeth. A new type of custom-made copings was prepared on 10 extracted teeth and their marginal fit was observed microscopically by means of a mechanical device, and software was employed to measure the gap. The marginal fit evaluation gave satisfactory values with mean values of the gap measurements below the clinically accepted limits (mean gap: 25.3 microm; minimum 7.3 microm, maximum 56.5 microm). The advantages of these new copings are: the rapidity of their preparation; the protection of the root canal treatment, because the coping with this chair-side method is prepared and cemented in one session; the low costs.

Automatic teeth axes calculation for well-aligned teeth using cost profile analysis along teeth center arch.

Science.gov (United States)

Kim, Gyehyun; Lee, Jeongjin; Seo, Jinwook; Lee, Wooshik; Shin, Yeong-Gil; Kim, Bohyoung

2012-04-01

In dental implantology and virtual dental surgery planning using computed tomography (CT) images, the examination of the axes of neighboring and/or biting teeth is important to improve the performance of the masticatory system as well as the aesthetic beauty. However, due to its high connectivity to neighboring teeth and jawbones, a tooth and/or its axis is very elusive to automatically identify in dental CT images. This paper presents a novel method of automatically calculating individual teeth axes. The planes separating the individual teeth are automatically calculated using cost profile analysis along the teeth center arch. In this calculation, a novel plane cost function, which considers the intensity and the gradient, is proposed to favor the teeth separation planes crossing the teeth interstice and suppress the possible inappropriately detected separation planes crossing the soft pulp. The soft pulp and dentine of each individually separated tooth are then segmented by a fast marching method with two newly proposed speed functions considering their own specific anatomical characteristics. The axis of each tooth is finally calculated using principal component analysis on the segmented soft pulp and dentine. In experimental results using 20 clinical datasets, the average angle and minimum distance differences between the teeth axes manually specified by two dentists and automatically calculated by the proposed method were 1.94° ± 0.61° and 1.13 ± 0.56 mm, respectively. The proposed method identified the individual teeth axes accurately, demonstrating that it can give dentists substantial assistance during dental surgery such as dental implant placement and orthognathic surgery.

Minor and trace elements in human bones and teeth

Energy Technology Data Exchange (ETDEWEB)

Iyengar, G V; Tandon, L

1999-07-01

Chemical elements play a great role in the metabolism of bones and teeth. Some elements are beneficial (F at non toxic concentrations in bones and teeth, supplementation of Cu, Mn and Zn along with Ca to delay or prevent the onset of osteoporosis) and some others (chronic exposure to Pb even at moderate concentrations, and excessive exposures to F as in fluorosis situations) are detrimental for the normal functioning of the skeleton. Knowledge on the roles played by both groups of elements can be enhanced if reliable compositional picture is available for scrutiny. The present survey was undertaken to assess the literature status on chemical composition of bones and teeth, and revealed that much needs to be done in order to have tangible collection of meaningful data. In this context, there is a desperate need for harmonization (types of samples chosen, procedures adopted to process the specimens, and finally the determination of analytes) to generate comparable data. To begin with, it is necessary to develop a bioanalytical protocol that exemplifies the merits and demerits of analyzing bones and teeth. Identification of any particular type of bone as a representative sample for the whole skeleton appears to be a far cry. Even if such a representative segment of a particular bone is identified, the logistics related to medico-legal (autopsy) and anatomical (biopsy) parameters will prevail as decisive factors. For the sake of gaining a comprehensive insight into the distribution of various trace elements in different types of bones, it is necessary to carry out controlled investigations on different types of bones (and cortical and trabecular segments from the same sources) from the same cadaver under well defined sampling conditions. On the analytical side, development of hard tissue RMs for whole bone, as well as for cortical, trabecular and marrow segments separately, would be very helpful for future investigations. (author)

Minor and trace elements in human bones and teeth

International Nuclear Information System (INIS)

Iyengar, G.V.; Tandon, L.

1999-01-01

Chemical elements play a great role in the metabolism of bones and teeth. Some elements are beneficial (F at non toxic concentrations in bones and teeth, supplementation of Cu, Mn and Zn along with Ca to delay or prevent the onset of osteoporosis) and some others (chronic exposure to Pb even at moderate concentrations, and excessive exposures to F as in fluorosis situations) are detrimental for the normal functioning of the skeleton. Knowledge on the roles played by both groups of elements can be enhanced if reliable compositional picture is available for scrutiny. The present survey was undertaken to assess the literature status on chemical composition of bones and teeth, and revealed that much needs to be done in order to have tangible collection of meaningful data. In this context, there is a desperate need for harmonization (types of samples chosen, procedures adopted to process the specimens, and finally the determination of analytes) to generate comparable data. To begin with, it is necessary to develop a bioanalytical protocol that exemplifies the merits and demerits of analyzing bones and teeth. Identification of any particular type of bone as a representative sample for the whole skeleton appears to be a far cry. Even if such a representative segment of a particular bone is identified, the logistics related to medico-legal (autopsy) and anatomical (biopsy) parameters will prevail as decisive factors. For the sake of gaining a comprehensive insight into the distribution of various trace elements in different types of bones, it is necessary to carry out controlled investigations on different types of bones (and cortical and trabecular segments from the same sources) from the same cadaver under well defined sampling conditions. On the analytical side, development of hard tissue RMs for whole bone, as well as for cortical, trabecular and marrow segments separately, would be very helpful for future investigations. (author)

Profil jaringan lunak wajah kasus borderline maloklusi klas I pada perawatan ortodonti dengan dan tanpa pencabutan gigi (Facial soft tissue profile on borderline class I malocclusion in orthodontic treatment with or without teeth extraction

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Pinandi Sri Pudyani

2013-12-01

Full Text Available Background: Determination of orthodontic treatment plan with or without teeth extraction remains controversial, especially in borderline cases, so it requires more data and information to establish appropriate treatment plans in order to obtain optimal treatment results. Purpose: The study was aimed to determine the facial soft tissue changes in the borderline class I cases treated with and without tooth extraction on post-orthodontic treatment. Methods: The study was conducted on 28 lateral cephalograms, divided into two groups; 13 cases with tooth extraction, and 15 cases without tooth extraction. The subject criterias were as follows; class I malocclusion treated with straightwire technique, skeletal class I, in range of age between 18 to 30 years old, normal overjet 2-4 mm, arch length discrepancy between 2.5 to 5 mm, Index of Fossa Canine (IFC between 37% to 44%, did not using extraoral devices, and treated with teeth extraction of 4 second premolars or without tooth extraction. The measurement of nasolabial angle, labiomental angle, and linear position of the upper and lower lip to E-Ricketts line were done on each cephalogram before and after orthodontic treatment. Results: In teeth extraction cases, there was a change on upper and lower lips positions (p<0.05, but there were no changes on nasolabial angle and labiomental angle (p>0.05. In non teeth extraction cases, there were no changes in nasolabial angle, labiomental angle, and lips positions (p>0.05. Both of groups also have indicated that there were no changes on linear position of the upper and lower lip (p>0.05. Post-orthodontic treatment indicated a significant differences between extraction and nonextraction cases on nasolabial and labiomental angle, and lips position (p<0.05. Conclusion: The facial soft tissue profile changes on teeth extraction case was more retruded than non- teeth extraction case.Latar belakang: Penentuan rencana perawatan ortodonti dengan pencabutan atau

Fracture resistance of teeth submitted to several internal bleaching protocols.

Science.gov (United States)

Leonardo, Renato de Toledo; Kuga, Milton Carlos; Guiotti, Flávia Angélica; Andolfatto, Carolina; Faria-Júnior, Norberto Batista de; Campos, Edson Alves de; Keine, Kátia Cristina; Dantas, Andrea Abi Rached

2014-03-01

The aim of this study was to evaluate the fracture resistance of teeth submitted to several internal bleaching protocols using 35% hydrogen peroxide (35HP), 37% carbamide peroxide (37CP), 15% hydrogen peroxide with titanium dioxide nanoparticles (15HPTiO2) photoactivated by LED-laser or sodium perborate (SP). After endodontic treatment, fifty bovine extracted teeth were divided into five groups (n = 10): G1-unbleached; G2-35HP; G3-37CP; G4-15HPTiO2 photoactivated by LED-laser and G5-SP. In the G2 and G4, the bleaching protocol was applied in 4 sessions, with 7 days intervals between each session. In the G3 and G5, the materials were kept in the pulp teeth for 21 days, but replaced every 7 days. After 21 days, the teeth were subjected to compressive load at a cross head speed of 0.5 mm/min, applied at 135° to the long axis of the root using an eletromechanical testing machine, until teeth fracture. The data were submitted to ANOVA and Tukey tests (α = 5%). The 35HP, 37CP, 15HPTiO2 and SP showed similar fracture resistance teeth reduction (p > 0.05). All bleaching treatments reduced the fracture resistance compared to unbleached teeth (p endodontically-treated teeth, but there were no differences between each other. There are several internal bleaching protocols using hydrogen peroxide in different concentrations and activation methods. This study evaluated its effects on fracture resistance in endodontically-treated teeth.

Teeth characterization using ion beam analysis

International Nuclear Information System (INIS)

Rizzutto, M.A.; Added, N.; Tabacniks, M.H.; Falla-Sotelo, F.; Curado, J.F.; Francci, C.; Markarian, R.A.; Quinelato, A.; Youssef, F.; Mori, M.; Youssef, M.

2006-01-01

A collaboration project between the School of Dentistry and the Institute of Physics of the University of Sao Paulo has been established to measure elemental concentrations in teeth by proton induced X-ray emission (PIXE) and heavy ion elastic recoil detection analysis (HI-ERDA) techniques. Data on trace elements in human, bovine and swine teeth, analyzed by PIXE with a 2.4 MeV proton beam, were compared and concentrations for several elements were obtained with tens of μg/g sensitivity. HI-ERDA measurements employing a 52 MeV Cl beam were done to evaluate changes in elementary concentration in dental enamel after bleaching treatment with different products in 25 bovine incisors teeth. This nondestructive technique allowed the measurements of Ca, P, O and C concentrations above the limit of 100 μg/g. (author)

Phototherapy up-regulates dentin matrix proteins expression and synthesis by stem cells from human-exfoliated deciduous teeth.

Science.gov (United States)

Turrioni, Ana Paula S; Basso, Fernanda G; Montoro, Liege A; Almeida, Leopoldina de Fátima D de; Costa, Carlos A de Souza; Hebling, Josimeri

2014-10-01

The aim of this study was to evaluate the effects of infrared LED (850nm) irradiation on dentin matrix proteins expression and synthesis by cultured stem cells from human exfoliated deciduous teeth (SHED). Near-exfoliation primary teeth were extracted (n=3), and SHED cultures were characterized by immunofluorescence using STRO-1, CD44, CD146, Nanog and OCT3/4 antibodies, before experimental protocol. The SHEDs were seeded (3×10(4) cells/cm(2)) with DMEM containing 10% FBS. After 24-h incubation, the culture medium was replaced by osteogenic differentiation medium, and the cells were irradiated with LED light at energy densities (EDs) of 0 (control), 2, or 4J/cm(2) (n=8). The irradiated SHEDs were then evaluated for alkaline phosphatase (ALP) activity, total protein (TP) production, and collagen synthesis (SIRCOL™ Assay), as well as ALP, collagen type I (Col I), dentin sialophosphoprotein (DSPP), and dentin matrix acidic phosphoprotein (DMP-1) gene expression (qPCR). Data were analyzed by Kruskal-Wallis and Mann-Whitney tests (α=0.05). Increased ALP activity and collagen synthesis, as well as gene expression of DSPP and ALP, were observed for both EDs compared with non-irradiated cells. The ED of 4J/cm(2) also increased gene expression of COL I and DMP-1. In conclusion, infrared LED irradiation was capable of biostimulating SHEDs by increasing the expression and synthesis of proteins related with mineralized tissue formation, with overall better results for the energy dose of 4J/cm(2). Phototherapy is an additional approach for the clinical application of LED in Restorative Dentistry. Infrared LED irradiation of the cavity's floor could biostimulate subjacent pulp cells, improving local tissue healing. Copyright © 2014 Elsevier Ltd. All rights reserved.

The aesthetic treatment for anterior teeth with lost crown by endorestoration

Directory of Open Access Journals (Sweden)

Nanik Zubaidah

2009-06-01

Full Text Available Background: The aesthetic has an important role in social life, especially the anterior teeth. The aesthetic abnormality of anterior teeth i.e. discoloration, malpotition or the anterior teeth with crown damage for more than one third or all part of crown is lost due to caries or other causes, will influence its appearance especially during smile. Purpose: The aim of this case report, therefore, is to show how teeth with clinical crown lost or only the root left still can be treated by endorestoration treatment in order to reconstruct the shape and function of the teeth similar to the original ones. Case: Female 52 years old with the lost crown of anterior teeth. The patient did not want her teeth to be extracted. Case Management: The abnormality of these teeth are still able to be reconstructed by endorestoration i.e. endodontic treatment with post and core insertion in the root canal will increase its retention and recovery by the porcelain crown fused to metal to recover the original formation and aesthetic and thus has the normal refunction. The treatment, it improve the confidence of the patient, and also can function normally. The patient did not feel pain. Ronsenography showed the periapical lesion diminished, the neighbor gingival was going better in both function and color. Conclusion: Endorestoration treatment on the anterior teeth with lost crown could recover the normal function, dental aesthetic and self confidence.

[Biologico-periodontal considerations in restoration of teeth partially destroyed by caries or traumatism].

Science.gov (United States)

Carrillo Martínez, J J; Zermeño Ibarra, J A; Mercado Martínez, E G; Villanueva Neuman, Y; Castellanos Olmedo, R

1990-01-01

Since a great number of teeth could be rehabilitated and not extracted, in this paper we analyze the relation Perio-protesis by the point of the biology of marginal periodontal ligament, and the different options to establish this relations when are lost by decay or traumatism. We discuss the contraindications to avoid greater problems than benefits when intend to rehabilitate lost teeth.

Depth profilometric case studies in caries diagnostics of human teeth using modulated laser radiometry and luminescence

Science.gov (United States)

Jeon, Raymond J.; Mandelis, Andreas; Abrams, Stephen H.

2003-01-01

Simultaneous measurements from human teeth of photothermal radiometric (PTR) and luminescence (LM) signals induced by an intensity modulated laser have been performed to assess the feasibility of detecting deep lesions and near-surface cracks, to examine the effects of varying enamel thicknesses, the presence of fillings, and stains on the surface of teeth. A commercial dc luminescence monitoring instrument (DIAGNOdent by KaVo) was also used to examine a set of teeth for comparison purposes with PTR and LM. PTR amplitude signals from carious regions and from thin enamel were higher than those from healthy regions and thicker enamel. A crack produces a peak in the PTR amplitude scan, as well as a sudden change in the luminescence amplitude at the corresponding point. At low frequencies (5 Hz), the PTR amplitude showed high sensitivity to a deep (about 2 mm) lesion, while at high frequencies (700 Hz) it was more sensitive to surface cracks. It was concluded that by selecting proper modulation frequencies of the laser, measurements of PTR and LM signals could be used as a dental diagnostic technique with a small, inexpensive, low-power (<30 mW) semiconductor laser as a light source emitting in the optical window range of hard tissue (650-1000 nm).

Histological evaluation of the pulp in teeth from dogs with naturally occurring periodontal disease.

Science.gov (United States)

Nemec, Ana; Pavlica, Zlatko; Stiblar-Martincic, Draga; Petelin, Milan; Erzen, Damjan; Crossley, David

2007-12-01

The purpose of this investigation was to evaluate the pulp of dog teeth affected by advanced periodontal disease. Histological examination was done on demineralized teeth extracted during clinical treatment of mature, client owned small and medium-size breed dogs with either good periodontal health or with advanced naturally occurring periodontal disease. Routinely stained sections from 5 clinically normal teeth and 22 teeth with advanced periodontitis from dogs between 5 and 12-years of age were examined using light microscopy. The pulp cavities of most teeth were narrow with low cellularity and some fibrosis of the pulp. Findings specific to periodontally affected teeth included acute and chronic pulpitis, vascular congestion, and pulp necrosis. A glomus body was identified in the pulp of one tooth and areas of poorly mineralized cementum were seen in both normal and diseased teeth. Age related changes in dog teeth appear similar to those reported for man and the rat. In addition to age related changes, the pulp of dog teeth with advanced periodontal disease were frequently inflamed or necrotic. This may reflect the advanced periodontitis affecting these teeth or a mechanical effect related to excessive tooth mobility. Further study is required to determine the etiology and significance of these findings and to investigate pulp status in less severely diseased teeth.

The morphology of amputated human teeth and its relation to mechanical properties after restoration treatment

Science.gov (United States)

Gugger, Jonas; Krastl, Gabriel; Huser, Marius; Deyhle, Hans; Müller, Bert

2010-09-01

The increased susceptibility to fracture of root canal- and post-treated teeth is less affected by alterations of the dentin structure, but seems to crucially depend on the loss of coronal tooth substance. The surface, available for adhesion of the composite material in the root canal and in the coronal part of the tooth, is assumed to be of key importance for the fracture resistance. Thus, an appropriate three-dimensional method should be identified to determine the adhesive surface with necessary precision. For this purpose, severely decayed teeth were simulated decapitating clinical crowns. After root canal filling and post space preparation, impressions of the root canal and the amputation surface were obtained using silicone. Micro computed tomography scans of these impressions were acquired. For one selected specimen, an additional high-resolution scan was recorded at a synchrotron radiation source. Software of ImageLab served for the extraction of the amputation interface, the post surface and the post volume from the tomography data, which have been finally correlated with the Young's modulus and the maximal load derived from mechanical tests. The morphological parameters show a realistic relationship to the mechanical tests performed after the restoration treatments and are consequently important for improving the dental skills.

The influence of extractions caries cause on the development of malocclusion and need for orthodontic treatment.

Science.gov (United States)

Melsen, B; Terp, S

1982-01-01

The influence of premature extraction of deciduous teeth, and extraction of permanent teeth due to caries on the frequency of malocclusions was analysed. The patient group comprised 915 children aged 8-16 from a province of Northern Italy. 204 children had experienced premature loss of deciduous teeth and 442 had had permanent teeth extracted, due to caries. The permanent teeth most frequently extracted were the first molars. It was obvious that extraction caries cause had detrimental effect on the development of occlusion resulting in an increased frequency of malocclusions. The frequency of single malocclusion traits was compared between the groups of children with and without loss of teeth. The malocclusion traits most frequently observed in children who had experienced extraction, were dentitional anomalies due to malaligned teeth. Only minor changes in the occlusal anomalies could be observed. There was, however, a pronounced increase in the need for minor as well as major orthodontic treatment. On the basis of these findings it could be concluded that extraction of teeth due to caries should be avoided if the aim of dental service on a population basis is to ensure a well functioning dentition for the maximum number of people.

Implant site development by orthodontic forced eruption of nontreatable teeth: a case report.

Science.gov (United States)

Rokn, Amir Reza; Saffarpour, Anna; Sadrimanesh, Rouzbeh; Iranparvar, Kaveh; Saffarpour, Aida; Mahmoudzadeh, Majid; Soolari, Ahmad

2012-01-01

Loss of bone and soft tissue attachment are common sequelae of periodontitis that may jeopardize the aesthetic outcome and compromise the functional and aesthetic outcomes of treatment. The following case report describes one of the most predictable techniques of vertical ridge augmentation, which is orthodontic extrusion or forced eruption of hopeless teeth. A 34-year-old woman who presented with severe attachment loss and deep pockets was diagnosed with generalized aggressive periodontitis. The mobile maxillary incisors were consequently extracted and were replaced with dental implants. However, prior to extraction, orthodontic extrusion of the hopeless incisors was performed to correct vertical ridge defects. Following extrusion and extraction of the maxillary incisors, to prevent soft tissue collapse and to preserve the papillae during socket healing, the crowns of the extracted teeth were used as pontics on a removable partial provisional denture. After 8 weeks, the implants were placed, and an immediate functional restoration was delivered. After 4 months of healing, a fixed definitive partial prosthesis was fabricated and delivered. After periodontal treatment, over a 2-year period, the progression of aggressive periodontitis was controlled. The mean vertical movement of marginal bone was 3.6 mm. The use of the crowns of extracted teeth appears to be an effective method to maintain papillae. Orthodontic extrusion is a predictable method for the correction of vertical ridge defects. Orthodontic treatment does not aggravate or hasten the progression of aggressive periodontitis.

Wisdom Teeth Management

Science.gov (United States)

Wisdom Teeth Management Wisdom teeth, or third molars, are the last teeth to develop and appear in your mouth. They come ... of third molars, disease status, and to suggest management options ranging from removal to a monitored retention ...

Teeth and irradiation in head and neck cancer

International Nuclear Information System (INIS)

Thariat, J.; Ortholan, C.; Thariat, J.; Darcourt, V.; Poissonnet, G.; Dassonville, O.; Marcy, P.Y.; Bozec, A.; Ortholan, C.; Santini, J.; Thariat, J.; Mones, E. de; Darcourt, V.; Poissonnet, G.; Dassonville, O.; Bozec, A.; Santini, J.; Savoldelli, C.; Odin, G.; Guevara, N.; Marcy, P.Y.; Bensadoun, R.J.

2010-01-01

Pre-irradiation dental care depends on teeth health, fields and dose of irradiation, compliance to fluorides, cessation of tobacco and psycho-social cofactors. Dental care aims at preventing complications and preserving the quality of life (eating, speech and aesthetics). Approximately 11% of patients do not require any pre-irradiation dental care. Dental complications vary from slight colorations of the teeth to major complication such as osteoradionecrosis. Osteoradionecrosis rates vary from 1 to 9%, and may be decreased by using a 21-day delay between extractions and irradiation, provided that it does not postpone cancer treatment, with a dose-dependent risk ( 60 Gy). Osteoradionecrosis occurs spontaneously (35%), mostly involves the mandible (85%). (authors)

Evaluation of bond strength of self-etching adhesives having different pH on primary and permanent teeth dentin.

Science.gov (United States)

Ozmen, Bilal; Koyuturk, Alp Erdin; Tokay, Ugur; Cortcu, Murat; Sari, Mustafa Erhan

2015-10-16

The purpose of this in vitro study was to evaluate the dentin shear bond strength of 4 self-etching adhesives having a different pH on primary and permanent teeth dentin. The occlusal enamel was removed from 60 freshly extracted third molar and 60 primary second molar human teeth, which were randomly separated into 4 groups (n = 15). Four adhesive systems were applied: G-Bond (GC Corporation, Tokyo, Japan, pH: 1.5), Futura Bond M (Voco, Cuxhaver, Germany, pH: 1.4), Adper Prompt L-Pop (3M/ESPE, St Paul, MN, USA, pH: 0.8), and Clearfil S(3) Bond (Kuraray Medical, Tokyo, Japan, pH: 2.7) according to the manufacturer's instructions. After the application of dentin bonding agents, a composite resin material (Z250 Restorative A2, 3M ESPE, St. Paul, MN, USA) for permanent teeth and a compomer resin material (Dyract Extra A2, Dentsply, Konstanz, Germany) for primary teeth was applied onto the prepared dentin surfaces. The data were obtained by using a universal test machine at a crosshead speed of 1 mm/min. The mean values were compared using Tukey's multiple comparison test. Although there was no difference between adhesives on the permanent teeth, Clearfil S3 adhesive showed higher bond (18.07 ± 0.58 MPa) (P>0.05). Lower bond strength values were obtained from primary teeth and especially G-Bond adhesive (9.36 ± 0.48 MPa) (Padhesives with different pH and solvent types can be used successfully for permanent teeth dentin but adhesives with low pH did not provide greater shear bond strength values.

Periodontal Reasons for Tooth Extraction in Adult Population in Greece

OpenAIRE

Chrysanthakopoulos, Nikolaos A.

2010-01-01

Aim: The aim of this study was to investigate the prevalence of permanent teeth extracted due to periodontal disease and its relation to several aspects such as age, gender and type of extracted teeth due to periodontal and non-periodontal reasons, among patients attending a private practice. Material and Methods: Study population consisted of 600 patients, 270 males and 330 females, aged 18 to 74 years from a private practice in Greece. The reasons for extractions of teeth in the sample for ...

Pulpectomy procedures in primary molar teeth

OpenAIRE

Hany Mohamed Aly Ahmed

2014-01-01

Premature loss of primary molars can cause a number of undesirable consequences including loss of arch length, insufficient space for erupting premolars and mesial tipping of the permanent molars. Pulpectomy of primary molar teeth is considered as a reasonable treatment approach to ensure either normal shedding or a long-term survival in instances of retention. Despite being a more conservative treatment option than extraction, efficient pulpectomy of bizarre and tortuous root canals encased ...

Differential Nuclear and Mitochondrial DNA Preservation in Post-Mortem Teeth with Implications for Forensic and Ancient DNA Studies

Science.gov (United States)

Higgins, Denice; Rohrlach, Adam B.; Kaidonis, John; Townsend, Grant; Austin, Jeremy J.

2015-01-01

Major advances in genetic analysis of skeletal remains have been made over the last decade, primarily due to improvements in post-DNA-extraction techniques. Despite this, a key challenge for DNA analysis of skeletal remains is the limited yield of DNA recovered from these poorly preserved samples. Enhanced DNA recovery by improved sampling and extraction techniques would allow further advancements. However, little is known about the post-mortem kinetics of DNA degradation and whether the rate of degradation varies between nuclear and mitochondrial DNA or across different skeletal tissues. This knowledge, along with information regarding ante-mortem DNA distribution within skeletal elements, would inform sampling protocols facilitating development of improved extraction processes. Here we present a combined genetic and histological examination of DNA content and rates of DNA degradation in the different tooth tissues of 150 human molars over short-medium post-mortem intervals. DNA was extracted from coronal dentine, root dentine, cementum and pulp of 114 teeth via a silica column method and the remaining 36 teeth were examined histologically. Real time quantification assays based on two nuclear DNA fragments (67 bp and 156 bp) and one mitochondrial DNA fragment (77 bp) showed nuclear and mitochondrial DNA degraded exponentially, but at different rates, depending on post-mortem interval and soil temperature. In contrast to previous studies, we identified differential survival of nuclear and mtDNA in different tooth tissues. Futhermore histological examination showed pulp and dentine were rapidly affected by loss of structural integrity, and pulp was completely destroyed in a relatively short time period. Conversely, cementum showed little structural change over the same time period. Finally, we confirm that targeted sampling of cementum from teeth buried for up to 16 months can provide a reliable source of nuclear DNA for STR-based genotyping using standard

A novel mutation of adenomatous polyposis coli (APC) gene results in the formation of supernumerary teeth.

Science.gov (United States)

Yu, Fang; Cai, Wenping; Jiang, Beizhan; Xu, Laijun; Liu, Shangfeng; Zhao, Shouliang

2018-01-01

Supernumerary teeth are teeth that are present in addition to normal teeth. Although several hypotheses and some molecular signalling pathways explain the formation of supernumerary teeth, but their exact disease pathogenesis is unknown. To study the molecular mechanisms of supernumerary tooth-related syndrome (Gardner syndrome), a deeper understanding of the aetiology of supernumerary teeth and the associated syndrome is needed, with the goal of inhibiting disease inheritance via prenatal diagnosis. We recruited a Chinese family with Gardner syndrome. Haematoxylin and eosin staining of supernumerary teeth and colonic polyp lesion biopsies revealed that these patients exhibited significant pathological characteristics. APC gene mutations were detected by PCR and direct sequencing. We revealed the pathological pathway involved in human supernumerary tooth development and the mouse tooth germ development expression profile by RNA sequencing (RNA-seq). Sequencing analysis revealed that an APC gene mutation in exon 15, namely 4292-4293-Del GA, caused Gardner syndrome in this family. This mutation not only initiated the various manifestations typical of Gardner syndrome but also resulted in odontoma and supernumerary teeth in this case. Furthermore, RNA-seq analysis of human supernumerary teeth suggests that the APC gene is the key gene involved in the development of supernumerary teeth in humans. The mouse tooth germ development expression profile shows that the APC gene plays an important role in tooth germ development. We identified a new mutation in the APC gene that results in supernumerary teeth in association with Gardner syndrome. This information may shed light on the molecular pathogenesis of supernumerary teeth. Gene-based diagnosis and gene therapy for supernumerary teeth may become available in the future, and our study provides a high-resolution reference for treating other syndromes associated with supernumerary teeth. © 2017 The Authors. Journal of

Effects of various cone-beam computed tomography settings on the detection of recurrent caries under restorations in extracted primary teeth

OpenAIRE

Kamburo?lu, K?van?; S?nmez, G?l; Berkta?, Zeynep Serap; Kurt, Hakan; ?zen, Do?ukan

2017-01-01

Purpose The aim of this study was to assess the ex vivo diagnostic ability of 9 different cone-beam computed tomography (CBCT) settings in the detection of recurrent caries under amalgam restorations in primary teeth. Materials and Methods Fifty-two primary teeth were used. Twenty-six teeth had dentine caries and 26 teeth did not have dentine caries. Black class II cavities were prepared and restored with amalgam. In the 26 carious teeth, recurrent caries were left under restorations. The oth...

Teeth in the Line of Fracture: To Retain or Remove?

Science.gov (United States)

Samson, Jimson; John, Reena; Jayakumar, Shalini

2010-01-01

The purpose of this study was to analyze mandibular fracture site, relationship of the fracture line to the periodontium, vitality of teeth, displacement of the fracture segments and their implications, and determine whether to retain or remove the teeth in the fracture line. Fifty patients with 62 fractures were involved in this study. An electric pulp tester was used to measure the pulpal response. The degree of fracture displacement and the relationship of the fracture line to the periodontium were evaluated using panoramic radiographs. Fractures of the parasymphysis region constituted a majority of 60.87% in the gross displacement category. Four of 50 patients showed no response presurgically and minimal response postoperatively on pulp vitality testing. Patients with teeth in the fracture line showing no response on pulp vitality testing should be advised extraction to avoid further complications. PMID:22132255

Prevalence of vertical root fracture as the reason for tooth extraction in dental clinics.

Science.gov (United States)

Yoshino, Koichi; Ito, Koji; Kuroda, Masahiko; Sugihara, Naoki

2015-07-01

The aim of this study was to investigate the prevalence, by gender, of vertical root fracture (VRF) as the main reason for the extraction of permanent teeth in dental clinics in Tokyo. Participating dentists were requested to provide information about extractions of permanent teeth they had performed from 1 January 2013 to 30 June 2013. The main reasons for extraction were categorized as follows: VRF, caries (horizontal root fracture included), periodontal disease and others. At a total of 24 clinics, 736 teeth were extracted from 626 patients during the 6-month period. A total of 233 teeth were extracted by VRF (31.7%), and 93.6% of these were endodontically treated teeth. Among non-vital extracted teeth, 82.1% (179/218) had cast posts or screw posts. The percentage of extraction due to VRF was 29.4% in males and 34.7% in females. In females, the percentage of extractions due to VRF (34.7%) was higher than for periodontal disease (28.1%). In males, the percentage of extractions due to VRF increased with age (p < 0.05). The tooth types with the highest percentage of extractions due to VRF were the upper canine (46.7%), lower second premolar (48.0%) and lower first molar (50.0%) in males and the upper first premolar (43.3%), upper second premolar (44.4%), lower second premolar (53.8%) and lower first molar (54.5%) in females. These results indicate that we need to pay more attention to maintaining vital teeth while being aware of the particular tooth types in which VRF most frequently occurs.

Remarkable resilience of teeth.

Science.gov (United States)

Chai, Herzl; Lee, James J-W; Constantino, Paul J; Lucas, Peter W; Lawn, Brian R

2009-05-05

Tooth enamel is inherently weak, with fracture toughness comparable with glass, yet it is remarkably resilient, surviving millions of functional contacts over a lifetime. We propose a microstructural mechanism of damage resistance, based on observations from ex situ loading of human and sea otter molars (teeth with strikingly similar structural features). Section views of the enamel implicate tufts, hypomineralized crack-like defects at the enamel-dentin junction, as primary fracture sources. We report a stabilization in the evolution of these defects, by "stress shielding" from neighbors, by inhibition of ensuing crack extension from prism interweaving (decussation), and by self-healing. These factors, coupled with the capacity of the tooth configuration to limit the generation of tensile stresses in largely compressive biting, explain how teeth may absorb considerable damage over time without catastrophic failure, an outcome with strong implications concerning the adaptation of animal species to diet.

A study of geographical variations in the concentrations of plutonium and radiostrontium in human teeth throughout the British Isles

International Nuclear Information System (INIS)

O'Donnell, Rauiri

1993-05-01

Concern has been expressed about the impact on humans of plutonium and radiostrontium releases from nuclear installations in the United Kingdom, with public interest focusing on reported leukaemia clusters in the vicinity of some of these installations. In particular, it is not clear whether such discharges result in and increase in the body burden of plutonium and radiostrontium (present as a consequence of global fallout) in the local population. In this collaborative study the comparative exposures to 239,240Pu and 90Sr of different geographically located child populations in the British Isles have been examined using teeth removed from children for orthodontic purposes. Minute traces on 239,240Pu were found to be present in children's teeth. The overall mean concentration was 5+4 mBq/kg (ash), which is three orders of magnitude lower than reported total activities. Approximately 75% of the samples analysed showed concentrations below the mean value. Although there is considerable scatter in the data, there is some evidence of a marginal enhancement in the 239,240Pu concentration measured in the general vicinity of Cumbria, where the BNF plc. nuclear fuel reprocessing complex is located. Concentrations of 90Sr in teeth exceeded those of plutonium by three orders of magnitude, the overall mean being 8+5Bq/kg (ash). However, there was no evidence of any enhancement in the levels throughout Cumbria. No correlation was observed between 239,240Pu or 90Sr concentrations and mean annual rainfall, not was there any correlation between the levels of these radionuclides in the same samples. The plutonium and radiostrontium concentrations measured in teeth are similar to those reported for human bone in the British Isles and suggests that teeth can be used as an indicator of skeletal burden. On the basis of the above mentioned data, estimates have been made of the approximate risks of leukaemia and non-Hodgkins lymphoma assuming chronic intakes of these radionuclides. The

[Cryopreservation of teeth].

Science.gov (United States)

Zimmerli, Melanie; Filippi, Andreas

2010-01-01

After tooth loss dental implants or fixed prosthetic restorations are not indicated in children and adolescents due to incomplete maxillary and mandibular development. Cryopreservation is a method for long-term storage of healthy teeth which were removed for orthodontic reasons or due to traumatic origin. These preserved teeth can be used as autogenous replants or transplants after tooth loss. During transport to and from the freezing facilities prior to freezing the teeth are stored in a cell culture medium. The tooth is transferred into a freezing tube containing cell culture medium and cryoprotectant DMSO. Teeth autotransplanted after cryopreservation show vitality of the PDL cells. Usually no enamel and/or dentinal cracks can be observed. After tooth loss transplantation of cryopreserved teeth could be an effective and biological therapy for tooth replacement.

A Case of Maxillary Protrusion with Congenitally Missing Canine Teeth in the Mandible

OpenAIRE

松井, 啓至; 酒徳, 明彦

1996-01-01

A patient that had a maxillary protrusion with congenitally missing canine teeth in the mandible was successfully treated with the extraction of the maxillary first premolars. The patient's cooperation in wearing headgear appliance was highly favorable. Her profile changes were pronounced and esthetically pleasing. A review of her post-treatment records revealed an excellent esthetic and occlusal result even though the first premolars were aligned instead of the canine teeth in the mandible. ...

Histopathologic study on irradiated human developing teeth

Energy Technology Data Exchange (ETDEWEB)

Takeda, Yasunori (Iwate Medical Coll., Morioka (Japan). School of Dentistry)

1982-12-01

The patient was a 7-year-old boy who had been suffering from Ewing's sarcoma originating in the mandible. Irradiation with 8000 rad of Linac was performed on the mandible prior to mandibulectomy. The results of the histopathologic examination of the teeth including resected material were as follows: 1. Although the tumor tissue was not found in the resected material, complete resoption of the medullar trabecular bone with fibrosis was noted in the area between the first molar region and the mandibular ramus. 2. The first and the second premolar teeth were in the early stage of root formation, and conglomerates of dysplastic dentin were formed in the proliferative zones. This dysplastic dentin was surrounded by loose fibrous connective tissues. 3. The dysplastic dentin showed low mineralization, embedded irregular arranged-fibrous tissue matrix and scattered various-sized lacunae containing a few tiny and pyknotic cells. 4. Irregularly arranged odontoblasts with a pyknotic appearance were found along the tubular dentin, but diffuse fibrosis occurred in the pulpal tissues. 5. The first molar tooth had completed its root formation. Various amounts of osteodentin were formed at the secondary dentin layer. Inner-resorption of dentin and fibrosis of the pulpal tissue were also found. These changes concerning the first molar tooth were also due to the effects of irradiation. 6. The second molar tooth was resorbed by tumor infiltration, and dysplastic dentin was on the resorbed surface of the dentin.

Lead and cadmium in human teeth from Jordan by atomic absorption spectrometry: Some factors influencing their concentrations

Energy Technology Data Exchange (ETDEWEB)

Alomary, A. [Department of Chemistry, Yarmouk University, Irbid (Jordan)]. E-mail: ahmedalomary1000@hotmail.com; Al-Momani, I.F. [Department of Chemistry, Yarmouk University, Irbid (Jordan); Massadeh, A.M. [Department of Medicinal Chemistry and Pharmacognosy, Faculty of Pharmacy, Jordan University of Science and Technology, Irbid (Jordan)

2006-10-01

The aim of this study was to measure the concentrations of lead (Pb) and cadmium (Cd) in human teeth and to investigate the affecting factors. Teeth samples (n = 268) were collected from people living in different cities in Jordan including Amman, Zarqa, Al-Mafraq and Irbid and analyzed for Pb and Cd using atomic absorption spectrometry (AAS). A questionnaire was used to gather information on each person, such as age, sex, place where the patient lives, smoking, presence of amalgam fillings inside the mouth, and whether the patient uses toothpaste or not. The mean concentrations of Pb and Cd were 28.91 {mu}g/g and 0.44 {mu}g/g, respectively. The results indicate that there is a clear relation between Pb and Cd concentrations and the presence of amalgam fillings, smoking, and place of living. Pb was sex-dependent, whereas Cd was not. Our results show that Pb and Cd concentrations in samples obtained from Al-Mafraq and Irbid are higher than those obtained from Amman and Zarqa. Pb was highest in Mafraq, whereas Cd was highest in Irbid. The Pb and Cd concentrations in teeth from smokers (means: Pb = 31.89 {mu}g/g, Cd = 0.49 {mu}g/g) were significantly higher than those from nonsmokers (means: Pb = 24.07 {mu}g/g, Cd = 0.37 {mu}g/g). Pb and Cd concentrations in teeth of patients with amalgam fillings (means: Pb = 31.02 {mu}g/g and Cd = 0.52 {mu}g/g) were significantly higher than those from patients without amalgam fillings (means: Pb = 26.87 {mu}g/g and Cd = 0.41 {mu}g/g). Our results show that brushing the teeth daily with toothpaste does not significantly decrease the concentration of both Pb and Cd. The mean concentrations of Pb and Cd do not vary significantly between the ages 20-30, 31-40, and 41-50, but both increased rapidly at age 51-60.

Lead and cadmium in human teeth from Jordan by atomic absorption spectrometry: Some factors influencing their concentrations

International Nuclear Information System (INIS)

Alomary, A.; Al-Momani, I.F.; Massadeh, A.M.

2006-01-01

The aim of this study was to measure the concentrations of lead (Pb) and cadmium (Cd) in human teeth and to investigate the affecting factors. Teeth samples (n = 268) were collected from people living in different cities in Jordan including Amman, Zarqa, Al-Mafraq and Irbid and analyzed for Pb and Cd using atomic absorption spectrometry (AAS). A questionnaire was used to gather information on each person, such as age, sex, place where the patient lives, smoking, presence of amalgam fillings inside the mouth, and whether the patient uses toothpaste or not. The mean concentrations of Pb and Cd were 28.91 μg/g and 0.44 μg/g, respectively. The results indicate that there is a clear relation between Pb and Cd concentrations and the presence of amalgam fillings, smoking, and place of living. Pb was sex-dependent, whereas Cd was not. Our results show that Pb and Cd concentrations in samples obtained from Al-Mafraq and Irbid are higher than those obtained from Amman and Zarqa. Pb was highest in Mafraq, whereas Cd was highest in Irbid. The Pb and Cd concentrations in teeth from smokers (means: Pb = 31.89 μg/g, Cd = 0.49 μg/g) were significantly higher than those from nonsmokers (means: Pb = 24.07 μg/g, Cd = 0.37 μg/g). Pb and Cd concentrations in teeth of patients with amalgam fillings (means: Pb = 31.02 μg/g and Cd = 0.52 μg/g) were significantly higher than those from patients without amalgam fillings (means: Pb = 26.87 μg/g and Cd = 0.41 μg/g). Our results show that brushing the teeth daily with toothpaste does not significantly decrease the concentration of both Pb and Cd. The mean concentrations of Pb and Cd do not vary significantly between the ages 20-30, 31-40, and 41-50, but both increased rapidly at age 51-60

Histological Evaluation of Allium sativum Oil as a New Medicament for Pulp Treatment of Permanent Teeth.

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Mohammad, Shukry Gamal; Raheel, Syed Ahmed; Baroudi, Kusai

2015-02-01

The objective of this study was to evaluate the histo pathology effects of two medicaments Allium sativum oil and formocresol on the remaining pulp tissue of the permanent teething children. A total of 18 premolars were included in this study. Two sound premolars were extracted and subjected to histological examination to show the normal pulp tissue. Pulpo tomy procedure was performed in the rest of the remaining 16 premolars; half of them using Allium sativum oil and the rest of the tested premolars were medicated using formocresol and all were sealed with suitable restoration. Then, premolars extracted at variable intervals (48 hours, 2 weeks, 1 month, 2 months), stained using hemotoxylin and eosin etain (H&E) and prepared for histopathology examination. Histological evaluation seemed far more promising for Allium sativum oil than formocresol. Histological evaluation revealed that teeth treated with Allium sativa oil showed infammatory changes that had been resolved in the end of the study. On the contrary, the severe chronic infammation of pulp tissue accompanied with formocresol eventually produced pulp necrosis with or without fibrosis. In addition, pulp calcification was evidenced in certain cases. Allium sativum oil is a biocompatible material that is compatible with vital human pulp tissue. It offers a good healing potential, leaving the remaining pulp tissue healthy and functioning.

Non-syndromic supernumerary teeth: report of a case with 6 supernumerary teeth

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Taghibakhsh M

2011-02-01

Full Text Available "nBackground and Aims: Multiple supernumerary teeth are rare and often found in association with syndromes such as Gardner, Cleidocranial dysplasia and cleft lip and palate, with a much less chance for isolated"nnon-syndromic cases. The aim of this study was to report a case with 6 supernumerary teeth without syndromic association."nCase Report: The patient was a 33 year-old female, referred to oral diseases and diagnosis department with chief complaint of sensitivity to cold and hot food in right upper premolar region. Oral examination revealed 5 erupted lingually supernumerary teeth (four in mandibular and one in maxillary premolar region, respectively. Further panoramic radiography clarified an extra impacted tooth in the palatal region of left premolar maxillary area. All extra teeth had been appeared since the age of 17 during one year, as the patient claimed. Medical history and thorough clinical and paraclinical examinations were not significant except for the hypothyroidism, since 5 years ago. No other family member noticed to be the case. Based on our findings, a diagnosis of non-syndromic multiple supernumerary teeth was established."nConclusion: A thorough examination of each patient presented with supernumerary teeth, including panoramic and intraoral radiographic images may provide valuable information regarding accompanying syndromes and unerupted teeth. Early diagnosis is an essential step for orthodontic or surgical decisions making, preventing or avoiding worsening complications such as malocclusion, adjacent normal teeth delayed eruption or rotation, diasthema, cystic lesions and resorption of contiguous teeth.

ANTIPLAQUE AND ANTIGINGIVITIS EFFECTS OF A GEL CONTAINING PUNICA GRANATUM LINN EXTRACT. A DOUBLE-BLIND CLINICAL STUDY IN HUMANS

Science.gov (United States)

Salgado, Alexandre Daher Yunes; Maia, Juliana Lemos; Pereira, Sérgio Luís da Silva; de Lemos, Telma Leda Gomes; Mota, Olívia Morais de Lima

2006-01-01

Objectives: The antiplaque and antigingivitis effects of a gel containing 10% Punica granatum Linn extract were evaluated using a 21-day partial-mouth experimental model of gingivitis. Methods: 23 volunteers participated in this cross-over, doubleblind study, carried out in 2 phases of 21 days each. For each period of the experiment, an acrylic toothshield was made for each volunteer to carry the test or placebo gel as well as to avoid brushing of the 4 experimental teeth (posterior teeth in the lower left quadrant). The subjects were randomly assigned to use either the placebo gel (control group) or the test gel (experimental group) and were instructed to brush the remaining teeth normally 3 times a day. On days 0 and 21, the visible plaque index (VPI) and gingival bleeding index (GBI) were recorded. Results: The results did not show statistically significant difference between control and experimental groups for either of the indices (VPI and GBI). Conclusion: The gel containing 10% Punica granatum Linn extract was not efficient in preventing supragingival dental plaque formation and gingivitis. PMID:19089066

Trace element analysis of teeth from pre-Columbian population groups in Mexico

International Nuclear Information System (INIS)

Solis, C.; Oliver, A.; Andrade, E.; Macias, R.; Mansilla, J.; Chavez-Lomeli, M.E.

1999-01-01

Human teeth from pre-Columbian and recent population groups have been analyzed by PIXE. Ancient teeth corresponding to children and adults were obtained from archaeological burials located in five geographic areas of Mexico. Inter-specific and inter-site differences in the trace element contents of enamel were compared in order to get some insight into differences in diet, environmental conditions, teeth health, disease state and post mortem alteration among the co-occurring populations. For permanent teeth from adults, small variations in trace element levels were found depending on the collection site or tooth health, but for deciduous teeth from children, the concentration of elements such as Mn, Fe and Sr varied considerably. In this work, the possible sources of variation are discussed. (author)

Phenotypic and growth characterization of human mesenchymal stem cells cultured from permanent and deciduous teeth

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Revathi Shekar

2012-01-01

Conclusions: Permanent and deciduous teeth are both viable sources of stem cells. The permanent teeth were easier to culture because of a lower chance of contamination with oral microflora. The growth characteristics of the cells obtained from both these sources were similar. However, there was a difference in the ratio of fibroblastoid cells to epithelioid cells between the cultures obtained from the permanent and deciduous teeth.

Evaluation of resistance of teeth subjected to fracture after endodontic treatment using different root canal sealers: An in vitro study

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S S Bhat

2012-01-01

Full Text Available Aims: The aim of this study was to compare the ex-vivo effects of different root canal sealers on the fracture resistance of endodontically treated teeth. Materials and Methods: Seventy-five freshly extracted human mandibular premolars were used for the study. The length was standardized to 14 mm and all the teeth were biomechanically prepared and divided into five different groups based on the type of root canal sealers used. Group I:- Roeko seal + gutta percha, Group II: AH plus ® root canal sealer + gutta percha, Group III: PULPDENT root canal sealer + gutta percha, Group IV: Zinc oxide-eugenol sealer + gutta percha, Group V: Control (unobturated teeth. The teeth were embedded in acrylic resin blocks and compressive strengths were measured using universal testing machine (Instron. Statistical Analysis Used: One-way ANOVA, unpaired t- test Results: Data obtained were statistically evaluated using one-way ANOVA and unpaired t-test. All groups showed a statistically significant result (P < 0.05. Teeth obturated with Group I and Group II showed higher resistance to fracture than teeth obturated with other three Groups. It was seen that the teeth obturated with group III showed a better fracture resistance than Group IV and there was no statistical significance found between Group and Group V. Conclusions: From this study, it has been concluded that both the resin based sealers that were used in this study were equally effective compared to that of the zinc oxide-based sealers and the control group. However, no significant results were obtained when the comparison was made between zinc oxide-eugenol and gutta-percha and the control group.

Effect of vital bleaching with solutions containing different concentrations of hydrogen peroxide and pineapple extract as an additive on human enamel using reflectance spectrophotometer: An in vitro study.

Science.gov (United States)

Vejai Vekaash, Chitra Janardhanan; Kumar Reddy, Tripuravaram Vinay; Venkatesh, Kondas Vijay

2017-01-01

This study aims to evaluate the color change in human enamel bleached with three different concentrations of hydrogen peroxide, containing pineapple extract as an additive in two different timings, using reflectance spectrophotometer. The study aimed to investigate the bleaching efficacy on natural teeth using natural enzymes. Baseline color values of 10 randomly selected artificially stained incisors were obtained. The specimens were divided into three groups of 20 teeth each: Group 1 - 30% hydrogen peroxide, Group II - 20% hydrogen peroxide, and Group III - 10% hydrogen peroxide. One half of the tooth was bleached with hydrogen peroxide, and other was bleached with hydrogen peroxide and pineapple extract for 20 min (Subgroup A) and 10 min (Subgroup B). The results were statistically analyzed using student's t -test. The mean ΔE values of Group IA (31.62 ± 0.9), Group IIA (29.85 ± 1.2), and Group IIIA (28.65 ± 1.2) showed statistically significant higher values when compared to the mean Δ E values of Group 1A (25.02 ± 1.2), Group IIA (22.86 ± 1.1), and Group IIIA (16.56 ± 1.1). Identical results were obtained in Subgroup B. The addition of pineapple extract to hydrogen peroxide resulted in effective bleaching.

Supernumerary teeth in clinical practice

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Anna K. Szkaradkiewicz

2011-07-01

Full Text Available Introduction: Hyperdontia is the condition of having supernumerary teeth, or teeth which appear in addition to the regular number of teeth. The prevalence rates of supernumerary teeth in the permanent dentition amounts 0.1-6.9%, and in deciduous dentition 0.4-0.8%. The presence of supernumerary teeth can be found in everyday dental practice.Case presentation: We describe 3 cases of patients with supernumerary teeth. First patient had supernumerary lateral incisor 12s, second - premolar fused, multicuspid, supernumerary deciduous tooth 64s of having several interconnected roots, and third - erupted odontoma between teeth 13 and 14. In all cases treatment involved the removal of the supernumerary tooth.Conclusions: The decision on proceeding with the supernumerary teeth should be based on the full clinical picture and interview. Early diagnosis and removal of supernumerary teeth allow to avoid or reduce possible complications.

Concentrations of amoxicillin and clindamycin in teeth following a single dose of oral medication.

Science.gov (United States)

Schüssl, Yvonne; Pelz, Klaus; Kempf, Jürgen; Otten, Jörg-Elard

2014-01-01

The main purpose of this study is the detection of amoxicillin and clindamycin concentrations in teeth. Eleven patients received 2 g of amoxicillin, and 11 patients received 600 mg of clindamycin in a single dose of oral medication at least 60 min prior to tooth extraction due to systemic diseases. The concentrations were determined in crowns and roots separately using liquid chromatography-tandem mass spectrometry (LC-MS-MS). Amoxicillin (13 samples) and clindamycin (12 samples) were detected in the samples of the root and crown preparations of the extracted teeth. The mean concentration of amoxicillin was 0.502 μg/g in the roots and 0.171 μg/g in the crowns. The mean concentration of clindamycin was 0.270 μg/g in the roots and 0.064 μg/g in the crowns. A single dose of oral amoxicillin and clindamycin leads to concentrations of both antibiotics in teeth which exceed the minimal inhibition concentration of some oral bacteria. The proof of antibacterial activity in dental hard tissue after oral single-dose application is new. The antimicrobial effect of amoxicillin and clindamycin concentrations in roots of teeth may be of clinical relevance to bacterial reinfection from dentinal tubules.

Photodynamic therapy with water-soluble phtalocyanines against bacterial biofilms in teeth root canals

Science.gov (United States)

Gergova, Raina; Georgieva, Tzvetelina; Angelov, Ivan; Mantareva, Vanya; Valkanov, Serjoga; Mitov, Ivan; Dimitrov, Slavcho

2012-06-01

The study presents the PDT with metal phthalocyanines on biofilms grown in root canals of ten representatives of the Gram-positive and the Gram-negative bacterial species and a fungus Candida albicans which cause aqute teeth infections in root canals.. The extracted human single-root teeth infected for 48 h with microorganisms in conditions to form biofilms of the above pathogens were PDT treated. The stage of biofilm formation and PDT effect of the samples of the teeth were determined by the scaning electron microscopy and with standard microbial tests. The PDT treating procedure included 10 min incubation with the respected phthalocyanine and irradiated with 660 nm Diode laser for 10 min. The most strongly antibacterial activity was achieved with zinc(II) phthalocyanine (ZnPc) against Enterococcus faecalis, Staphylococcus aureus and Moraxella catarrhalis. The other Gram-negative bacteria and Candida albicans were 10-100 times more resistant than the Gram-positive species. The Gram-negative Moraxella catarrhalis and Acinetobacter baumannii were more sensitive than the enterobacteria, but eradication of Pseudomonas aeruginosa in biofilm was insignificant. The influence of the stage of biofilm formation and the initial conditions (bacterial density, photosensitizer concentration and energy fluence of radiation) to the obtained level of inactivation of biofilms was investigated. The PDT with ZnPc photosensitizers show a powerful antimicrobial activity against the most frequent pathogens in endodontic infections and this method for inactivation of pathogens may be used with sucsses for treatment of the bacterial biofilms in the root canals.

Prevalence of delayed emergence of permanent teeth as a result of local factors.

Science.gov (United States)

Johnsen, D C

1977-01-01

Delayed emergence of permanent teeth as a result of local etiologic factors was found in 45 of 1,032(4.3%) persons ages 8 through 18 in a dentally indigent population. In 36 persons (3.4%) delayed emergence resulted from causes other than those associated with premature primary molar extraction. This statistic probably approximates the potential for this problem in a treated population group. Teeth most commonly involved were mandibular second premolars, maxillary canines, and maxillary central incisors. The most common causes, respectively, were space loss, palatal position, and mesiodens. Supernumerary, malformed, and congenitally missing teeth were more frequent in persons with delayed emergence than in the rest of the population sampled. The difference was statistically significant. No correlation was found between delayed emergence and sex of the patient. In this study, teeth delayed in emergence behaved as other teeth in that they exhibited normal root development and did not contribute to resorption of adjacent roots. Except for maxillary canines, enlarged follicular spaces did not develop after eruption

Regional early development and eruption of permanent teeth: case report.

Science.gov (United States)

Al Mullahi, A M; Bakathir, A; Al Jahdhami, S

2017-02-01

Early development and eruption of permanent teeth are rarely reported in scientific literature. Early eruption of permanent teeth has been reported to occur due to local factors such as trauma or dental abscesses in primary teeth, and in systemic conditions. Congenital diffuse infiltrating facial lipomatosis (CDIFL) is a rare condition that belongs to a group of lipomatosis tumours. In this disorder, the mature adipocytes invade adjacent soft and hard tissues in the facial region. Accelerated tooth eruption is one of the dental anomalies associated with CDIFL. A 3-year-old boy presented with a swelling of the lower lip localised early development and eruption of permanent teeth and dental caries involving many primary teeth. The planned treatment included biopsy of the swollen lower lip to confirm the diagnosis, surgical reduction and reconstruction of lip aesthetics. The management of the carious primary teeth included preventative and comprehensive dental care and extractions. These procedures were completed under general anaesthesia due to the child's young age and poor cooperation. The lip biopsy showed features of CDIFL such as the presence of infiltrating adipose tissue, prominent number of nerve bundles and thickened vessels. The high recurrence rate of CDIFL mandates long-term monitoring during the facial growth period of the child. Follow-up care by the paediatric dentist and maxillofacial surgeon has been required to manage all aspects of this congenital malformation. This rare disorder has many implications affecting child's facial aesthetics, psychological well being, developing occlusion and risk of dental caries. A multi-disciplinary approach is needed for management of this condition.

Improved extraction procedure for carotenoids from human milk.

Science.gov (United States)

Schweigert, F J; Hurtienne, A; Bathe, K

2000-05-01

An improved method for the extraction of the major carotenoids from human milk is described. Carotenoids were extracted from milk first with ethanol and n-hexane. Then, polar xanthophylls were extracted from n-hexane into ethanol/water. The remaining n-hexane was evaporated, the residue combined with the ethanolic milk fraction and the mixture briefly saponified. Carotenoids were extracted from the hydrolysate with n-hexane, combined with the polar xanthophylls from the non-saponified ethanol/water-extract and separated by HPLC. Using this method we were able to significantly improve the recovery of xanthophylls such as lutein and zeaxanthin from human milk. The recovery rate of all carotenoids was > 90%. This method might not only be of value for milk but should be especially useful in the extraction of carotenoids from human tissues such as the adipose tissue.

Preexisting Dentinal Microcracks in Nonendodontically Treated Teeth: An Ex Vivo Micro-computed Tomographic Analysis.

Science.gov (United States)

PradeepKumar, Angambakkam Rajasekaran; Shemesh, Hagay; Chang, Jeffrey Wen-Wei; Bhowmik, Ahendita; Sibi, Swamy; Gopikrishna, Velayutham; Lakshmi-Narayanan, Lakshmikanthanbharathi; Kishen, Anil

2017-06-01

This study evaluated the prevalence, location, and pattern of preexisting dentinal microcracks in roots of extracted teeth without endodontic treatment in patients from 2 age groups using micro-computed tomographic imaging. Six hundred thirty-three nonendodontically treated teeth extracted using an atraumatic procedure because of reasons unrelated to this study were collected and divided based on the patient age. Teeth were scanned with micro-computed tomographic imaging (resolution of 26.7 μm) to examine the presence of preexisting dentinal microcracks in roots. The characteristic features of preexisting dentinal microcracks determined were location, extent, length, and coronoapical distribution. Chi-square bivariate analysis was performed to assess the association between various parameters. Forty-five of 633 nonendodontically treated teeth exhibited preexisting microcracks in roots with a prevalence of 7.1%. The prevalence of preexisting microcracks was found to be 8.3% in older patients (40-70 years) compared with 3.7% in younger patients (20-39 years) (P < .050). A significant association was found between the preexisting microcracks in mandibular teeth (10.3%) when compared with maxillary teeth (2.9%) (P < .001). All preexisting microcracks were located mesiodistally; 66% occurred in the cervical and middle thirds of root. Only 33% of the preexisting microcracks were complete in nature, showing canal involvement. Complete dentinal microcracks exhibited a mean length of 6.9 mm, whereas incomplete cracks had a mean length of 3.75 mm (P < .001). Preexisting dentinal microcracks in roots of nonendodontically treated teeth occurred more often in older patients (40-70 years) in the mesiodistal direction. They were predominantly found in the cervical and middle thirds of root and were more likely to be incomplete in nature. Copyright © 2017 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Histobacteriologic Conditions of the Apical Root Canal System and Periapical Tissues in Teeth Associated with Sinus Tracts.

Science.gov (United States)

Ricucci, Domenico; Loghin, Simona; Gonçalves, Lucio S; Rôças, Isabela N; Siqueira, José F

2018-03-01

This histobacteriologic study described the pattern of intraradicular and extraradicular infections in teeth with sinus tracts and chronic apical abscesses. The material comprised biopsy specimens from 24 (8 untreated and 16 treated) roots of teeth associated with apical periodontitis and a sinus tract. Specimens were obtained by periradicular surgery or extraction and were processed for histobacteriologic and histopathologic methods. Bacteria were found in the apical root canal system of all specimens, in the main root canal (22 teeth) and within ramifications (17 teeth). Four cases showed no extraradicular infection. Extraradicular bacteria occurred as a biofilm attached to the outer root surface in 17 teeth (5 untreated and 12 treated teeth), as actinomycotic colonies in 2 lesions, and as planktonic cells in 2 lesions. Extraradicular calculus formation (mineralized biofilm) was evident in 10 teeth. Teeth with chronic apical abscesses and sinus tracts showed a very complex infectious pattern in the apical root canal system and periapical lesion, with a predominance of biofilms. Copyright © 2017 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

[Nutrition, diet and dental health--de- and remineralisation of teeth].

Science.gov (United States)

Imfeld, Thomas

2008-02-01

There is little if any evidence that nutrition during the time of tooth formation has any clinically significant effect on caries susceptibility of erupted teeth in man. Caries, erosion and demastication are not nutritional diseases. They are, however, diet-related diseases because erupted teeth are subject to local chemical and mechanical effects of the diet contacting the teeth. Caries is the result of a chronic undermining demineralisation of the teeth by organic acids that are produced by the bacteria of the dental biofilm while fermenting carbohydrates from the human diet. Dental erosion is the result of a chronic localised loss of dental hard tissue etched away from the surface by acids derived from the diet or from gastric reflux. The physicochemical grounds of de- and remineralisation of teeth are explained using detailed diagrams. Initial caries lesions without cavitation of the surface can remineralise (heal) under conditions of low cariogenic diet and good oral hygiene. However, once the surface has broken and cavitation occurred, there is no alternative to restorative dental therapy because remineralisation is no more possible.

Multidisciplinary management of impacted central incisors due to supernumerary teeth and an associated dentigerous cyst

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Ritesh R Kalaskar

2011-01-01

Full Text Available Supernumerary teeth are the most common developmental dental anomaly resulting from hyperactivity of dental lamina, dichotomy, environmental factor, or polygenetic process of atavism. Supernumerary teeth present classical oral complication such as impaction of adjacent teeth, crowding, diastema formation, rotation, displacement of teeth, and occlusal interference. A dentigerous cyst associated with anterior supernumerary teeth (mesiodens is rare and accounts for 5% of all dentigerous cysts. The present case reports describe the successful management of the impacted permanent maxillary central incisor positioned high in the vestibule. A combination of surgical and orthodontic techniques was employed to improve treatment outcome with greater hard and soft tissue preservation and to prevent psychological problems. In the surgical phase, supernumerary teeth and dentigerous cyst were removed. Subsequently traction was employed by bonding bracket on the labial surface using closed and open eruption techniques. Successively, fixed orthodontic treatment was started to align permanent maxillary central incisors in an occlusal plane. Thus, combination of surgical and orthodontic method can be the treatment of choice over surgical extraction, implant placement, and surgical repositioning.

Multidisciplinary management of impacted central incisors due to supernumerary teeth and an associated dentigerous cyst.

Science.gov (United States)

Kalaskar, Ritesh R; Kalaskar, Ashita R

2011-01-01

Supernumerary teeth are the most common developmental dental anomaly resulting from hyperactivity of dental lamina, dichotomy, environmental factor, or polygenetic process of atavism. Supernumerary teeth present classical oral complication such as impaction of adjacent teeth, crowding, diastema formation, rotation, displacement of teeth, and occlusal interference. A dentigerous cyst associated with anterior supernumerary teeth (mesiodens) is rare and accounts for 5% of all dentigerous cysts. The present case reports describe the successful management of the impacted permanent maxillary central incisor positioned high in the vestibule. A combination of surgical and orthodontic techniques was employed to improve treatment outcome with greater hard and soft tissue preservation and to prevent psychological problems. In the surgical phase, supernumerary teeth and dentigerous cyst were removed. Subsequently traction was employed by bonding bracket on the labial surface using closed and open eruption techniques. Successively, fixed orthodontic treatment was started to align permanent maxillary central incisors in an occlusal plane. Thus, combination of surgical and orthodontic method can be the treatment of choice over surgical extraction, implant placement, and surgical repositioning.

Periapical abscess of the maxillary teeth and its fistulizations: Multi-detector CT study

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Sherif A. Shama

2013-09-01

Full Text Available Aim: The aim of this study was to assess the role of MDCT and the dedicated dental software in assessment of the periapical abscesses of the maxillary teeth and in detection of abnormal fistula as well as post intervention complications. Materials and methods: This study was conducted on 20 patients with periapical abscess of the maxillary teeth. MDCT machines were used in examination of all patients. Workstation was used for manipulation of data. Dedicated dental software was used in the evaluation of all diseased teeth. Results: Fourteen patients had their abscesses involving the maxillary molar and premolar teeth, six of them showed associated oro-antral fistula (42.8%. Four patients had their abscesses surrounding the apices of the incisors, two of them showed associated oro-nasal fistula (50%. None of the patients with periapical abscesses surrounding the roots of the canine teeth (n = 2 showed abnormal fistulization. Nine cases (45% showed missing crowns and retained roots due to previous trials of extractions. Two cases (10% of fracture of the maxillary alveolar process complicating trials of previous extraction were also encountered. Conclusion: The MDCT with its outstanding image quality of the bony structures supported by its 3-D and VR capabilities can detect the periapical dental abscess in a 3-D fashion, accurately define its location, size and extent and is excellent in evaluation of possible fistula. As compared to panorama X-ray, MDCT was more accurate in diagnosis of abnormal fistula and associated fracture of the alveolar process of the maxillary bone. KEYWORDS: Periapical abscess, MDCT, Oro-antral fistula, Oro-nasal fistula

Light-emitting diode assessment of dentinal defects: the role of presumed extraction forces

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Marcelo Santos Coelho

2017-07-01

Full Text Available Objectives The evaluation of iatrogenic dentinal defects in extracted teeth may be influenced by extraction forces and prolonged dry times. The purpose of this study was to compare the presence of dentinal defects in freshly extracted, periodontally compromised teeth with those in a group of teeth with uncontrolled extraction forces and storage time. Materials and Methods The experimental group consisted of eighteen roots obtained from teeth extracted due to periodontal reasons with class II or III mobility. They were kept in saline and sectioned within 1 hour following extraction. The control group consisted of matched root types obtained from an anonymous tooth collection, consistent with previous dentinal defect studies. The slices were obtained at 3, 6, and 9 mm from the apex. The imaging process exposed all specimens to no more than 60 seconds of dry time. The × 12.8 magnification was used for the 9 mm slices and × 19.2 magnification for the 3 mm and 6 mm slices under light-emitting diode (LED transillumination. The root canal spaces and periodontal tissues were masked to minimize extraneous factors that might influence the evaluators. Chi-square test was used for statistical analysis. Results Dentinal defects were detected in 17% of the experimental group teeth, compared to 61% of control teeth (p = 0.015. Conclusions LED transillumination assessment of freshly extracted roots with class II or III mobility showed smaller number of dentinal defects than roots with uncontrolled storage time and extraction forces. The use of freshly extracted roots with mobility should be considered for future dental defect assessment studies.

Histopathological evaluation of pulp after pulpotomy of primary teeth with sodium hypochlorite and formocresol

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Haghgoo R

2010-06-01

Full Text Available "nBackground and Aims: Formocresol is one of the most common pulpotomy medicaments for primary teeth. Because of its systemic and local side effects, it may be essential to use another material instead of formocresol. The aim of this study was to evaluate the histopothalogy of pulp after pulpotomy teeth with sodium hypochlorite and formocresol. "nMaterials and Methods: In this randomized clinical trial, 22 canine teeth that must be extracted because of orthodontic treatment were selected. The teeth were randomly divided into 2 groups (n=11 and pulpotomized with formocresol or sodium hypochlorite. These teeth were extracted after 2 months and pulpal response was evaluated according to the degree of inflammation and extent of pulpal involvement. Dentinal bridge formation was also evaluated. The data were analyzed by Mann-Whitney test. "nResults: In formocresol group, mild inflammation was seen in 4 and moderate inflammation in 3 and severe inflammation in 4 cases. In sodium hypochlorite group mild inflammation was seen in 6 cases and moderate inflammation in 4 cases and severe inflammation in 1 case. Mann-Whitney test revealed that this difference was not statistically significant (P>0.05. In formocresol group, necrosis was seen in 5 cases, but abscess and internal resorption were not seen in any cases. In sodium hypochlorite group, internal resorption was seen in 3 cases; but necrosis and abscess were not seen in any cases.  Mann-Whitney test showed that the difference between two groups was significant in terms of necrosis (P=0.02. In sodium hypochlorite group, dentinal bridge was formed in 3 cases; however, no dentinal bridge formation was seen in formocresol group. Mann-Whitney test showed that this difference was not significant statistically (P>0.05. "nConclusion: Based on the results of this study, sodium hypochlorite can be used as a pulpotomy agent in primary teeth.

Combined Orthodontic-surgical Treatment for Skeletal Class III Malocclusion with Multiple Impacted Permanent and Supernumerary Teeth: Case Report.

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Xue, Dai Juan And Feng

2014-01-01

In this report we describe a combined orthodontic and surgical treatment for a 14-year-old boy with severe skeletal class III deformity and dental problem. His upper posterior primary teeth in the left side were over-retained and 6 maxillary teeth (bilateral central incisors and canines, left first and second premolars) were impacted, together with 5 supernumerary teeth in both arches. The treatment protocol involved extraction of all the supernumerary and deciduous teeth, surgical exposure and orthodontic traction of the impacted teeth, a bimaxillary orthognathic approach including Lefort I osteotomy. Bilateral sagittal split ramus osteotomy (BSSRO) and genioplasty was performed to correct skeletal problem. After treatment, all of the impacted teeth were brought to proper alignment in the maxillary arch. A satisfied profile and good posterior occlusion was achieved. Treatment mechanics and consideration during different stages are discussed.

Photon dose conversion coefficients for the human teeth in standard irradiation geometries

Energy Technology Data Exchange (ETDEWEB)

Ulanovsky, A; Wieser, A; Zankl, M; Jacob, P

2005-07-01

Photon dose conversion coefficients for the human tooth materials are computed in energy range from 0.01 to 10 MeV by the Monte Carlo method. The voxel phantom Golem of the human body with newly defined tooth region and a modified version of the EGS4 code have been used to compute the coefficients for 30 tooth cells with different locations and materials. The dose responses are calculated for cells representing buccal and lingual enamel layers. The computed coefficients demonstrate a strong dependence on energy and geometry of the radiation source and a weaker dependence on location of the enamel voxels. For isotropic and rotational radiation fields the enamel dose does not show a significant dependence on tooth sample locations. The computed coefficients are used to convert from absorbed dose in teeth to organ dose or to integral air kerma. Examples of integral conversion factors from enamel dose to air kerma are given for several photon fluences specific for the Mayak reprocessing plant in Russia. The integral conversion factors are strongly affected by the energy and angular distributions of photon fluence, which are important characteristics of an exposure scenario for reconstruction of individual occupational doses. (orig.)

Screening of plant extracts for human tyrosinase inhibiting effects.

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Kim, M; Park, J; Song, K; Kim, H G; Koh, J-S; Boo, Y C

2012-04-01

Screening for tyrosinase (TYR) inhibitors potentially useful for control of skin pigmentation has been hampered by the limited availability of human TYR. To overcome this hurdle, we have established human embryonic kidney (HEK293)-TYR cells that constitutively express human TYR. In the current study, we assayed human TYR inhibition activities of 50 plant extracts using the lysates of transformed HEK293-TYR cells. The strongest inhibition of human TYR was shown by the extract of Vaccinium bracteatum Thunberg, followed by the extract of Morus bombycis Koidzumi. The former extract did not inhibit mushroom TYR activity whereas significant inhibition was observed with the latter extract, demonstrating the importance of using human TYR in the screening for human TYR inhibitors. Upon liquid-liquid partitioning of the extract from V. bracteatum, the active constituents were enriched in the ethyl acetate fraction, and the subsequent preparatory thin-layer chromatography identified p-coumaric acid (PCA) as the main active constituent. The hypo-pigmentation of PCA was verified in the MelanoDerm™ Skin Model. This study demonstrates that transformed HEK293-TYR cells could expedite the discovery of human TYR-specific inhibitors from natural sources which might be useful in the control of skin pigmentation. © 2012 The Authors. ICS © 2012 Society of Cosmetic Scientists and the Société Française de Cosmétologie.

The roentgenographic study on the thickness of the lamina dura in normal teeth

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Park, Chang Sik; Ahn, Hyung Kyu [Department of Dental Radiology, College of Dentistry, Seoul National University, Seoul (Korea, Republic of)

1976-11-15

The study was performed to investigate the thickness of laminadura of the human teeth in normal condition, which obtained from the intraoral roentgenograms of the 1200 cases taken by bisecting technique. All films were divided into the different ages, the different sexes, and the different location of the different teeth. The obtained results were as follows: 1. With advancing age in both sexes, the laminadura tends to become thinner as following. Average thickness of the whole cases. 2. In general, the alveolar crest is thickest among the root surfaces, apex, midroot followed, and the average thickness of the posterior teeth is thicker than that of the anterior teeth. 3. The mean value of the whole maxillary teeth is larger than the one of the whole mandibular teeth. 4. On the whole cases, the differences of male and female is about 0.019 mm, which is not a significant differences.

Clinical assessment of bone quality of human extraction sockets after conversion with growth factors.

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Ntounis, Athanasios; Geurs, Nico; Vassilopoulos, Philip; Reddy, Michael

2015-01-01

The study was conducted to evaluate the effect of mineralized freeze-dried bone allograft (FDBA), alone or in combination with growth factors in extraction sockets, on subjective assessment of bone quality during implant placement. Forty-one patients whose treatment plan involved extraction of anterior or premolar teeth were randomized into four groups: Group 1, collagen plug (control); Group 2, FDBA/β-tricalcium phosphate (β-TCP)/collagen plug; Group 3, FDBA/β-TCP/platelet-rich plasma (PRP)/collagen plug; Group 4, FDBA/β-TCP/recombinant human platelet-derived growth factor BB (rhPDGF-BB)/collagen plug. After 8 weeks of healing, implants were placed. The clinicians assessed bone quality according to the Misch classification. A benchtop calibration exercise test was conducted to evaluate agreement and accuracy of operators in recognizing different bone qualities. Differences were analyzed using one-way analysis of variance (ANOVA) or chi-square tests for continuous and categorical data. Pairwise comparisons were tested using least squares means (LS means). Spearman correlation coefficients were used to evaluate the relationship of bone growth with potential confounders. P .05). Inclusion of bone grafting is associated with a shift from D4 quality to D3 quality bone. Inclusion of PRP in bone grafting eliminates the incidence of D4 bone, establishing D3 and D2 quality bone as prevalent (56% vs. 42%, respectively). Inclusion of rhPDGF-BB and β-TCP in combination with the bone grafting has the same effect, although D2 quality is less prevalent. When compared to sockets grafted with FDBA/β-TCP/collagen plug alone, the sockets with growth factors demonstrated fewer residual bone graft particles. (1) Inclusion of bone grafting enhanced bone quality as assessed during implant placement. (2) Overall inclusion of PRP and rhPDGF-BB enhanced subjective bone quality, eliminating incidence of D4 quality in human extraction sockets. (3) The use of PRP or rhPDGF-BB may

Investigation of 16% carbamide-peroxide on the structure and properties and effect return enamel staining teeth whitening after their

OpenAIRE

Matvijenko Vladimir; Živković M.; Videnović G.; Kostić-Šubarić Lj.; Živković D.; Perić D.; Jovanović R.

2015-01-01

The most tooth whitening is a procedure that removes stains and various discolorations of tooth surface. Discoloration of teeth may be endogenous and exogenous nature. The aim of this study was to investigate the impact of bleaching combined with daily use of drinks that cause tooth discoloration. Evaluated the changes in surface structure of enamel, and changes in hardness after bleaching. Were 20 extracted teeth. The teeth are marked with longitudinal lines halves (medial vestibular and dis...

A Comparison of Computed Tomographic, Radiographic, Gross and Histological, Dental, and Alveolar Findings in 30 Abnormal Cheek Teeth from Equine Cadavers.

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Liuti, Tiziana; Smith, Sionagh; Dixon, Padraic M

2017-01-01

Equine cheek teeth disorders, especially pulpar/apical infections, can have very serious consequences due to the frequent extension of infection to the supporting bones and/or adjacent paranasal sinuses. Limited studies have assessed the accuracy of computed tomographic (CT) imaging in the diagnosis of these disorders, and no study has directly compared imaging and pathological findings of the alveoli of diseased equine cheek teeth. To validate the accuracy of CT and radiographic imaging of cheek teeth disorders by comparing CT and radiographic imaging, gross and histological findings in abnormal cheek teeth and their alveoli extracted from equine cadaver heads. Ex vivo original study. Fifty-four cadaver heads from horses with unknown histories that had died or been euthanized on humane grounds obtained from a rendering plant had radiography, CT imaging, and gross pathological examinations performed. Based on imaging and gross examination findings, 30 abnormal cheek teeth (26 maxillary and 4 mandibular) identified in 26 heads were extracted along with their dental alveoli where possible, and further CT imaging, gross, and histological examinations were performed. Eight maxillary cheek teeth (including four with attached alveolar bone) from these heads, that were normal on gross and CT examinations, were used as controls. Gross pathological and histological examinations indicated that 28/30 teeth, including two supernumerary teeth, had pulpar/apical infection, including pulpar and apical changes. A further supernumerary and a dysplastic tooth were also identified. Abnormal calcified tissue architecture was present in all three supernumerary and in the dysplastic tooth. CT imaging strongly indicated the presence of pulpar/apical infection in 27 of the 28 (96.4%) pulpar/apically infected teeth, including the presence of intrapulpar gas ( N  = 19/28), apical clubbing ( N  = 20), periapical halo ( N  = 4), root lysis or fragmentation ( N  = 7), and

High-precision Pb isotopic measurements of teeth and environmental samples from Sofia (Bulgaria): insights for regional lead sources and possible pathways to the human body

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Kamenov, George D.

2008-08-01

High-precision Pb isotopic measurements on teeth and possible sources in a given area can provide important insights for the lead (Pb) sources and pathways in the human body. Pb isotopic analyses on soils from the area of Sofia, Bulgaria show that Pb is contributed by three end-members represented by two natural sources and leaded gasoline. Sequential leaching experiments reveal that the alumosilicate fraction of the soils is mainly controlled by natural Pb derived from two mountain massifs bordering the city. Around 1/3 to a half of the Pb in the soil leachates, however, can be explained by contamination from leaded gasoline. Contemporary teeth from Sofia residents show very similar Pb isotopic compositions to the soil leachates, also indicating that around 1/3 to a half of the Pb can be explained by derivation from leaded gasoline. The remarkable isotopic similarities between the teeth and the most labile fractions of the local soils suggest that the lead can be derived from the latter. Pb incorporation in the human body via soil-plant-human or soil-plant-animal-human chains is unlikely due to the fact that no significant farming occurs in the city area. The isotopic compositions of the local soil labile fractions can be used as approximation of the bioaccessible lead for humans. Considering all possible scenarios it appears that soil and/or soil-born dust inhalation and/or ingestion is the most probable pathway for incorporation of local soil lead in the local population. The high-precision Pb isotope data presented in this work indicate that apparently the local soil is what plays major role in the human Pb exposure.

Trace Elements in Teeth by ICPMS

International Nuclear Information System (INIS)

Zahran, N.F.; Helal, A.I.; Amr, M.A.; Amr, M.A.; Al-saad, K.A.

2008-01-01

Teeth are reported to be suitable indicators of trace element exposure from environment and nutritional status. Inductively coupled plasma mass spectrometry (ICP-MS) is used to compare the trace element content of children's primary teeth and adult teeth. Primary teeth are collected from 28 children and 42 adult from non-industrial City. The data are assessed statistically using t-tests. The adult teeth contained significantly greater concentrations of Na, Mg, Al, Fe, Ni, Cu, Sr, Cd, Ba, Pb and U and significantly less Mn, Co, As, Se, Mo and Bi than the children teeth. Additional measurements on adult teeth pulps are performed. Comparison between trace element concentrations in health and caries teeth pulps show that the mean concentrations of Na, Al, K, Cr, Mn, Co, Cu, Zn, Mo, Ag, Bi and U are lower in caries than healthy teeth pulps. On the other hand, the mean concentrations of Mg, Cd and Pb are higher in caries samples than healthy teeth pulps

Neutron activation analysis for the optimal sampling and extraction of extractable organohalogens in human hari

International Nuclear Information System (INIS)

Zhang, H.; Chai, Z.F.; Sun, H.B.; Xu, H.F.

2005-01-01

Many persistent organohalogen compounds such as DDTs and polychlorinated biphenyls have caused seriously environmental pollution problem that now involves all life. It is know that neutron activation analysis (NAA) is a very convenient method for halogen analysis and is also the only method currently available for simultaneously determining organic chlorine, bromine and iodine in one extract. Human hair is a convenient material to evaluate the burden of such compounds in human body and dan be easily collected from people over wide ranges of age, sex, residential areas, eating habits and working environments. To effectively extract organohalogen compounds from human hair, in present work the optimal Soxhelt-extraction time of extractable organohalogen (EOX) and extractable persistent organohalogen (EPOX) from hair of different lengths were studied by NAA. The results indicated that the optimal Soxhelt-extraction time of EOX and EPOX from human hair was 8-11 h, and the highest EOX and EPOX contents were observed in hair powder extract. The concentrations of both EOX and EPOX in different hair sections were in the order of hair powder ≥ 2 mm > 5 mm, which stated that hair samples milled into hair powder or cut into very short sections were not only for homogeneous. hair sample but for the best hair extraction efficiency.

Fracture resistance of weakened teeth restored with condensable resin with and without cusp coverage

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Rafael Francisco Lia Mondelli

2009-06-01

Full Text Available OBJECTIVES: This in vitro study evaluated the fracture resistance of weakened human premolars (MOD cavity preparation and pulp chamber roof removal restored with condensable resin composite with and without cusp coverage. MATERIAL AND METHODS: Thirty human maxillary premolars were divided into three groups: Group A (control, sound teeth; Group B, wide MOD cavities prepared and the pulp chamber roof removed and restored with resin composite without cusp coverage; Group C, same as Group B with 2.0 mm of buccal and palatal cusps reduced and restored with the same resin. The teeth were included in metal rings with self-curing acrylic resin, stored in water for 24 h and thereafter subjected to a compressive axial load in a universal testing machine at 0.5 mm/min. RESULTS: The mean fracture resistance values ± standart deviation (kgf were: group A: 151.40 ± 55.32, group B: 60.54 ± 12.61, group C: 141.90 ± 30.82. Statistically significant differences were found only between Group B and the other groups (p<0.05. The condensable resin restoration of weakened human premolars with cusp coverage significantly increased the fracture resistance of the teeth as compared to teeth restored without cusp coverage. CONCLUSION: The results showed that cusp coverage with condensable resin might be a safe option for restoring weakened endodontically treated teeth.

Prevalence of two root canals in human mandibular anterior teeth in an Iranian population

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Saeed Rahimi

2013-01-01

Full Text Available Background: Complete debridement and obturation of the root canal system is a key factor in successful endodontic treatment and the operator should therefore have thorough knowledge of the root canal morphology of the teeth. Numerous studies have been carried out to investigate the canal configuration of different tooth types in various populations. Aims: The aim of the present study was to investigate the internal anatomy of mandibular incisors and canines in an Iranian population. Materials and Methods: A total of 463 mandibular anterior teeth, including 186 centrals, 128 laterals, and 149 canines, were examined. A standard clearing technique was used to make the teeth transparent. India ink was injected into the canals of the teeth and the samples were examined with a magnifying glass. The root canal configurations were categorized according to the Vertucci classification. Results: All the incisors in this study had one root, and 12.08% of the canines had two roots. We found a slightly higher prevalence of the second canal in incisors than in canines (36.62% vs. 20.48%. However, the probability of canines having two separate apical foramina was higher than that for incisors (12.08% vs. 0.64%. Conclusions: In view of the high prevalence of two-canaled mandibular anterior teeth found in this study, it would be prudent to assume that any mandibular anterior tooth being treated is two-canaled until a thorough search proves otherwise.

Comparative gene expression analysis of the human periodontal ligament in deciduous and permanent teeth.

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Je Seon Song

Full Text Available There are histological and functional differences between human deciduous and permanent periodontal ligament (PDL tissues. The aim of this study was to determine the differences between these two types of tissue at the molecular level by comparing their gene expression patterns. PDL samples were obtained from permanent premolars (n = 38 and anterior deciduous teeth (n = 31 extracted from 40 healthy persons. Comparative cDNA microarray analysis revealed several differences in gene expression between the deciduous and permanent PDL tissues. These findings were verified by qRT-PCR (quantitative reverse-transcription-polymerase chain reaction analysis, and the areas where genes are expressed were revealed by immunohistochemical staining. The expressions of 21 genes were up-regulated in deciduous relative to PDL tissues, and those of 30 genes were up-regulated in permanent relative to deciduous PDL tissues. The genes that were up-regulated in deciduous PDL tissues were those involved in the formation of the extracellular matrix (LAMC2, LAMB3, and COMP, tissue development (IGF2BP, MAB21L2, and PAX3, and inflammatory or immune reactions leading to tissue degradation (IL1A, CCL21, and CCL18. The up-regulated genes in permanent PDL tissues were related to tissue degradation (IL6 and ADAMTS18, myocontraction (PDE3B, CASQ2, and MYH10, and neurological responses (FOS, NCAM2, SYT1, SLC22A3, DOCK3, LRRTM1, LRRTM3, PRSS12, and ARPP21. The analysis of differential gene expressions between deciduous and permanent PDL tissues aids our understanding of histological and functional differences between them at the molecular level.

Comparative gene expression analysis of the human periodontal ligament in deciduous and permanent teeth.

Science.gov (United States)

Song, Je Seon; Hwang, Dong Hwan; Kim, Seong-Oh; Jeon, Mijeong; Choi, Byung-Jai; Jung, Han-Sung; Moon, Seok Jun; Park, Wonse; Choi, Hyung-Jun

2013-01-01

There are histological and functional differences between human deciduous and permanent periodontal ligament (PDL) tissues. The aim of this study was to determine the differences between these two types of tissue at the molecular level by comparing their gene expression patterns. PDL samples were obtained from permanent premolars (n = 38) and anterior deciduous teeth (n = 31) extracted from 40 healthy persons. Comparative cDNA microarray analysis revealed several differences in gene expression between the deciduous and permanent PDL tissues. These findings were verified by qRT-PCR (quantitative reverse-transcription-polymerase chain reaction) analysis, and the areas where genes are expressed were revealed by immunohistochemical staining. The expressions of 21 genes were up-regulated in deciduous relative to PDL tissues, and those of 30 genes were up-regulated in permanent relative to deciduous PDL tissues. The genes that were up-regulated in deciduous PDL tissues were those involved in the formation of the extracellular matrix (LAMC2, LAMB3, and COMP), tissue development (IGF2BP, MAB21L2, and PAX3), and inflammatory or immune reactions leading to tissue degradation (IL1A, CCL21, and CCL18). The up-regulated genes in permanent PDL tissues were related to tissue degradation (IL6 and ADAMTS18), myocontraction (PDE3B, CASQ2, and MYH10), and neurological responses (FOS, NCAM2, SYT1, SLC22A3, DOCK3, LRRTM1, LRRTM3, PRSS12, and ARPP21). The analysis of differential gene expressions between deciduous and permanent PDL tissues aids our understanding of histological and functional differences between them at the molecular level.

Rate of retraction of anterior teeth after canine distraction

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Litesh Singla

2017-01-01

Full Text Available Background and Objectives: Orthodontists have always strived to develop a new technique to reduce the treatment time with minimal patient cooperation. Canine distraction was introduced as an alternative technique for canine retraction in a minimum possible period of 3 weeks, thus avoiding taxing the anchorage by molars since the canines are retracted within the lag phase of molars. It has been proved by numerous studies that the bone mesial to canine after rapid canine distraction through the extraction socket is a new and immature. The objectives of this study were to evaluate the rate of retraction of anterior teeth, the time taken, and anchorage loss during the retraction of anterior teeth into this newly organized bone. Methods: Six orthodontic patients who required first premolar extractions were selected. Undermining of the interseptal bone distal to the canine was done, and canines were retracted into the extraction space of the first premolar, using a custom-made tooth borne intraoral distraction screw, following which the incisors were retracted into the newly formed bone using closing loops. The patients were called at weekly intervals to measure the amount of space left between canine and lateral incisor, and the rate of retraction was calculated after space was closed. Results: The present study showed that the rate of retraction of mandibular and maxillary teeth was 0.74 ± 0.39 mm and 0.73 ± 0.15 mm/week, respectively. The anchorage loss was found to be 1.83 ± 0.29 mm and 2.08 ± 0.38 mm in mandibular and maxillary arches, respectively. The time taken to retract the incisors was found to be 40.3 ± 1.5 and 41.7 ± 0.6 days for mandibular and maxillary arches, respectively. Interpretation and Conclusion: Retraction of incisors is faster in both maxillary and mandibular arches when the incisors are retracted immediately into the immature bone created after canine distraction.

Effect of bulk-fill base material on fracture strength of root-filled teeth restored with laminate resin composite restorations.

Science.gov (United States)

Taha, N A; Maghaireh, G A; Ghannam, A S; Palamara, J E

2017-08-01

To evaluate the effect of using a bulk-fill flowable base material on fracture strength and fracture patterns of root-filled maxillary premolars with MOD preparations restored with laminate restorations. Fifty extracted maxillary premolars were selected for the study. Standardized MOD cavities with endodontic treatment were prepared for all teeth, except for intact control. The teeth were divided randomly into five groups (n=10); (Group 1) sound teeth, (Group 2) unrestored teeth; (Group 3) MOD cavities with Vitrebond base and resin-based composite (Ceram. X One Universal); (Group 4) MOD cavities with 2mm GIC base (Fuji IX GP) and resin-based composite (Ceram. X One Universal) open laminate, (Group 5) MOD cavities were restored with 4mm of bulk-fill flowable base material (SDR) and resin-based composite (Ceram. X One Universal). All teeth were thermocycled and subjected to a 45° ramped oblique load in a universal testing machine. Fracture load and fracture patterns were recorded. Data were analyzed using one-way ANOVA and Dunnett's T3 test. Restoration in general increased the fracture strength compared to unrestored teeth. The fracture strength of group 5 (bulk-fill) was significantly higher than the fracture strength of the GIC laminate groups and not significantly different from the intact teeth (355±112N, P=0.118). The type of failure was unfavorable for most of the groups, with the majority being mixed failures. The use of a bulk-fill flowable base material significantly increased the fracture strength of extracted root-filled teeth with MOD cavities; however it did not improve fracture patterns to more favorable ones. Investigating restorative techniques that may improve the longevity of root-filled premolar teeth restored with direct resin restorations. Copyright © 2017 Elsevier Ltd. All rights reserved.

Teeth re-whitening effect of strawberry juice on coffee stained teeth

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Annisya Pramesti

2018-01-01

Full Text Available Many people favor coffee. However, regarding health and aesthetic dentistry, coffee gives a negative effect. Tanin in coffee causes a brown stain on the tooth surface. Therefore, in aesthetic dental care, teeth whitening has become popular matter. One of the natural ingredients used for teeth whitening treatment is strawberry. The purpose of this study was to obtained data regarding the effect of strawberry juice on the re-whitening process of the coffee-stained tooth enamel surface. This study was a pure experimental in-vitro using Friedman and Wilcoxon Matched Pairs Tests for statistical analysis. The population of this study was anterior teeth. The samples were maxillary central incisors. The sampling technique using sample size determination based on the testing formulas of the difference of two average data pairs resulted in 11 specimens. The result of the research showed that all coffee-stained teeth sample had an increasing enamel colour index. The samples were then applied with strawberry juice resulted in a significant average difference colour index value indicated by p<0.001. The conclusion of this research indicated that there was an effect of strawberry juice on the coffee-stained teeth re-whitening process.

Effects of various cone-beam computed tomography settings on the detection of recurrent caries under restorations in extracted primary teeth.

Science.gov (United States)

Kamburoğlu, Kıvanç; Sönmez, Gül; Berktaş, Zeynep Serap; Kurt, Hakan; Özen, Doĝukan

2017-06-01

The aim of this study was to assess the ex vivo diagnostic ability of 9 different cone-beam computed tomography (CBCT) settings in the detection of recurrent caries under amalgam restorations in primary teeth. Fifty-two primary teeth were used. Twenty-six teeth had dentine caries and 26 teeth did not have dentine caries. Black class II cavities were prepared and restored with amalgam. In the 26 carious teeth, recurrent caries were left under restorations. The other 26 intact teeth that did not have caries served as controls. Teeth were imaged using a 100×90-mm field of view and a 0.2-mm voxel size with 9 different CBCT settings. Four observers assessed the images using a 5-point scale. Kappa values were calculated to assess observer agreement. CBCT settings were compared with the gold standard using a receiver operating characteristic analysis. The area under the curve (AUC) values for each setting were compared using the chi-square test, with a significance level of α=.05. Intraobserver kappa values ranged from 0.366 to 0.664 for observer 1, from 0.311 to 0.447 for observer 2, from 0.597 to 1.000 for observer 3, and from 0.869 to 1 for observer 4. Furthermore, interobserver kappa values among the observers ranged from 0.133 to 0.814 for the first reading and from 0.197 to 0.805 for the second reading. The highest AUC values were found for setting 5 (0.5916) and setting 3 (0.5886), and were not found to be statistically significant ( P >.05). Variations in tube voltage and tube current did not affect the detection of recurrent caries under amalgam restorations in primary teeth.

Effects of various cone-beam computed tomography settings on the detection of recurrent caries under restorations in extracted primary teeth

Energy Technology Data Exchange (ETDEWEB)

Kamburoglu, Kivanc; Sonmez, Gul; Kurt, Hakan; Berktas, Zeynep Serap [Dept. of Dentomaxillofacial Radiology, Faculty of Dentistry, Ankara University, Ankara (Turkmenistan); Ozen, Dogukan [Dept. of Biostatistics, Faculty of Veterinary Medicine, Ankara University, Ankara (Turkmenistan)

2017-06-15

The aim of this study was to assess the ex vivo diagnostic ability of 9 different cone-beam computed tomography (CBCT) settings in the detection of recurrent caries under amalgam restorations in primary teeth. Fifty-two primary teeth were used. Twenty-six teeth had dentine caries and 26 teeth did not have dentine caries. Black class II cavities were prepared and restored with amalgam. In the 26 carious teeth, recurrent caries were left under restorations. The other 26 intact teeth that did not have caries served as controls. Teeth were imaged using a 100×90-mm field of view and a 0.2-mm voxel size with 9 different CBCT settings. Four observers assessed the images using a 5-point scale. Kappa values were calculated to assess observer agreement. CBCT settings were compared with the gold standard using a receiver operating characteristic analysis. The area under the curve (AUC) values for each setting were compared using the chi-square test, with a significance level of α=.05. Intraobserver kappa values ranged from 0.366 to 0.664 for observer 1, from 0.311 to 0.447 for observer 2, from 0.597 to 1.000 for observer 3, and from 0.869 to 1 for observer 4. Furthermore, interobserver kappa values among the observers ranged from 0.133 to 0.814 for the first reading and from 0.197 to 0.805 for the second reading. The highest AUC values were found for setting 5 (0.5916) and setting 3 (0.5886), and were not found to be statistically significant (P>.05). Variations in tube voltage and tube current did not affect the detection of recurrent caries under amalgam restorations in primary teeth.

Effects of various cone-beam computed tomography settings on the detection of recurrent caries under restorations in extracted primary teeth

International Nuclear Information System (INIS)

Kamburoglu, Kivanc; Sonmez, Gul; Kurt, Hakan; Berktas, Zeynep Serap; Ozen, Dogukan

2017-01-01

The aim of this study was to assess the ex vivo diagnostic ability of 9 different cone-beam computed tomography (CBCT) settings in the detection of recurrent caries under amalgam restorations in primary teeth. Fifty-two primary teeth were used. Twenty-six teeth had dentine caries and 26 teeth did not have dentine caries. Black class II cavities were prepared and restored with amalgam. In the 26 carious teeth, recurrent caries were left under restorations. The other 26 intact teeth that did not have caries served as controls. Teeth were imaged using a 100×90-mm field of view and a 0.2-mm voxel size with 9 different CBCT settings. Four observers assessed the images using a 5-point scale. Kappa values were calculated to assess observer agreement. CBCT settings were compared with the gold standard using a receiver operating characteristic analysis. The area under the curve (AUC) values for each setting were compared using the chi-square test, with a significance level of α=.05. Intraobserver kappa values ranged from 0.366 to 0.664 for observer 1, from 0.311 to 0.447 for observer 2, from 0.597 to 1.000 for observer 3, and from 0.869 to 1 for observer 4. Furthermore, interobserver kappa values among the observers ranged from 0.133 to 0.814 for the first reading and from 0.197 to 0.805 for the second reading. The highest AUC values were found for setting 5 (0.5916) and setting 3 (0.5886), and were not found to be statistically significant (P>.05). Variations in tube voltage and tube current did not affect the detection of recurrent caries under amalgam restorations in primary teeth

The management of over closured anterior teeth due to attrition

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Eha Djulaeha

2009-12-01

Full Text Available Background: Tooth is the hardest tissue in human body, that can be injured because of attrition process. For old people, denture attrition process is caused by psysiological process relating with the mastication function which also supported by some bad habits such an bruxism, premature contact, and consuming habit of abrasive food. Attrition or abrasion can also be happened with patien’t dentition who does not have teeth subtutition for long time due the lost of their maxillary as well as mandibulary. The pasient will loose their vertical dimension of occlusion, injure, and the lower jaw becomes over closed which is called over closure. Purpose: This article reported the management of over closured anterior teeth due to attrition. Case: a seventy six year old woman patient came to Prosthodontic Clinic in Faculty of Dentistry, Airlangga University, to rehabilitate her upper and lower severe attrited anterior teeth and her posterior teeth. The patient has experienced of wearing acrylic removable mandibular partial denture ten years ago. Unfortunaly, the denture was uncomfortable, and she did not wear it anymore since five years ago. Case management: The severe attrition of anterior teeth with the lost of occlusal vertical dimension can be treated by improving the occlusal vertical dimension gradually. The treatment is then followed by the increasing of the height of the anterior teeth by lengthening the crown teeth of upper jaw with 12 units of span bridge and the acrylic removable partial denture of lower jaw. Conclusion: The severe attrition of anterior teeth with the lost of occlusal vertical dimension can be treated by improving the occlusal vertical dimension gradually, using long span bridge and acrylic removable partial denture.

The study of barium concentration in deciduous teeth, impacted teeth, and facial bones of Polish residents.

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Fischer, Agnieszka; Malara, Piotr; Wiechuła, Danuta

2014-10-01

The study determines the concentration of Ba in mineralized tissues of deciduous teeth, permanent impacted teeth, and facial bones. The study covers the population of children and adults (aged 6-78) living in an industrial area of Poland. Teeth were analyzed in whole, with no division into dentine and enamel. Facial bones and teeth were subjected to the following preparation: washing, drying, grinding in a porcelain mortar, sample weighing (about 0.2 g), and microwave mineralization with spectrally pure nitric acid. The aim of the study was to determinate the concentration of Ba in deciduous teeth, impacted permanent teeth, and facial bones. The concentration of barium in samples was determined over the ICP OES method. The Ba concentration in the tested bone tissues amounted to 2.2-15.5 μg/g (6.6 μg/g ± 3.9). The highest concentration of Ba was present in deciduous teeth (10.5 μg/g), followed by facial bones (5.2 μg/g), and impacted teeth (4.3 μg/g) (ANOVA Kruskal-Wallis rank test, p = 0.0002). In bone tissue and impacted teeth, Ba concentration increased with age. In deciduous teeth, the level of Ba decreased with children's age.

Pulp nerve fibers distribution of human carious teeth: An immunohistochemical study

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Tetiana Haniastuti

2010-12-01

Full Text Available Background: Human dental pulp is richly innervated by trigeminal afferent axons that subserve nociceptive function. Accordingly, they respond to stimuli that induce injury to the pulp tissue. An injury to the nerve terminals and other tissue components in the pulp stimulate metabolic activation of the neurons in the trigeminal ganglion which result in morphological changes in the peripheral nerve terminals. Purpose: The aim of the study was to observe caries-related changes in the distribution of human pulpal nerve. Methods: Under informed consents, 15 third molars with caries at various stages of decay and 5 intact third molars were extracted because of orthodontic or therapeutic reasons. All samples were observed by micro-computed tomography to confirm the lesion condition 3-dimensionally, before decalcifying with 10% EDTA solution (pH 7.4. The specimens were then processed for immunohistochemistry using anti-protein gene products (PGP 9.5, a specific marker for the nerve fiber. Results: In normal intact teeth, PGP 9.5 immunoreactive nerve fibers were seen concentrated beneath the odontoblast cell layer. Nerve fibers exhibited an increased density along the pulp-dentin border corresponding to the carious lesions. Conclusion: Neural density increases throughout the pulp chamber with the progression of caries. The activity and pathogenicity of the lesion as well as caries depth, might influence the degree of neural sprouting.Latar belakang: Pulpa gigi manusia diinervasi oleh serabut saraf trigeminal yang berespon terhadap stimuli penyebab perlukaan dengan menimbulkan rasa sakit. Perlukaan pada akhiran saraf dan komponen lain dari pulpa akan menstimulasi aktivasi metabolik dari neuron pada ganglion trigeminal sehingga mengakibatkan perubahan morfologi pada akhiran saraf perifer. Tujuan: Penelitian ini bertujuan untuk mengamati perubahan distribusi saraf pada pulpa gigi manusia yang disebabkan oleh proses karies. Metode: Penelitian ini menggunakan

Tribulus terrestris Extract Improves Human Sperm Parameters In Vitro

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Khaleghi, Sara; Bakhtiari, Mitra; Asadmobini, Atefeh; Esmaeili, Farzane

2016-01-01

Objective. The object of present study was to investigate the effects of direct addition of Tribulus terrestris extract on human sperm parameters. Design. Semen specimens from 40 healthy men volunteers were divided into 4 groups: one group received no treatment (control group) while the others were incubated with 20, 40, and 50 µg/mL of T terrestris extract (experimental groups). Motility, viability, and DNA fragmentation were assessed in all groups. Results. The incubation of human semen with 40 and 50 μg/mL of T terrestris extract significantly enhanced total sperm motility, number of progressive motile spermatozoa, and curvilinear velocity over 60 to 120 minutes’ holding time (P terrestris extract (P terrestris extract to human sperm could affect male fertility capacity. PMID:27694560

Tribulus terrestris Extract Improves Human Sperm Parameters In Vitro.

Science.gov (United States)

Khaleghi, Sara; Bakhtiari, Mitra; Asadmobini, Atefeh; Esmaeili, Farzane

2016-09-30

The object of present study was to investigate the effects of direct addition of Tribulus terrestris extract on human sperm parameters. Semen specimens from 40 healthy men volunteers were divided into 4 groups: one group received no treatment (control group) while the others were incubated with 20, 40, and 50 µg/mL of T terrestris extract (experimental groups). Motility, viability, and DNA fragmentation were assessed in all groups. The incubation of human semen with 40 and 50 μg/mL of T terrestris extract significantly enhanced total sperm motility, number of progressive motile spermatozoa, and curvilinear velocity over 60 to 120 minutes' holding time (P terrestris extract (P terrestris extract to human sperm could affect male fertility capacity. © The Author(s) 2016.

Highly efficient DNA extraction method from skeletal remains

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Irena Zupanič Pajnič

2011-03-01

Full Text Available Background: This paper precisely describes the method of DNA extraction developed to acquire high quality DNA from the Second World War skeletal remains. The same method is also used for molecular genetic identification of unknown decomposed bodies in routine forensic casework where only bones and teeth are suitable for DNA typing. We analysed 109 bones and two teeth from WWII mass graves in Slovenia. Methods: We cleaned the bones and teeth, removed surface contaminants and ground the bones into powder, using liquid nitrogen . Prior to isolating the DNA in parallel using the BioRobot EZ1 (Qiagen, the powder was decalcified for three days. The nuclear DNA of the samples were quantified by real-time PCR method. We acquired autosomal genetic profiles and Y-chromosome haplotypes of the bones and teeth with PCR amplification of microsatellites, and mtDNA haplotypes 99. For the purpose of traceability in the event of contamination, we prepared elimination data bases including genetic profiles of the nuclear and mtDNA of all persons who have been in touch with the skeletal remains in any way. Results: We extracted up to 55 ng DNA/g of the teeth, up to 100 ng DNA/g of the femurs, up to 30 ng DNA/g of the tibias and up to 0.5 ng DNA/g of the humerus. The typing of autosomal and YSTR loci was successful in all of the teeth, in 98 % dekalof the femurs, and in 75 % to 81 % of the tibias and humerus. The typing of mtDNA was successful in all of the teeth, and in 96 % to 98 % of the bones. Conclusions: We managed to obtain nuclear DNA for successful STR typing from skeletal remains that were over 60 years old . The method of DNA extraction described here has proved to be highly efficient. We obtained 0.8 to 100 ng DNA/g of teeth or bones and complete genetic profiles of autosomal DNA, Y-STR haplotypes, and mtDNA haplotypes from only 0.5g bone and teeth samples.

Evaluation of microleakage in single-rooted teeth obturated with thermoplasticized gutta-percha using various endodontic sealers: an in-vitrostudy

International Nuclear Information System (INIS)

Lone, M.M.; Khan, F.; Lone, M.A.

2018-01-01

Objective:To compare apical microleakage of extracted, single-rooted teeth obturated with thermoplasticized injectable gutta-percha using two different endodontic sealers (calcium-hydroxide and resin based). Study Design:An experimental study. Place and Duration of Study:The Aga Khan University Hospital (AKUH), Dental Clinics and Laboratory from June to September 2015. Methodology:The study was conducted using extracted teeth. After access cavities were made, cleaning and shaping of root canals was done in 70 teeth. Teeth were randomly allocated into two groups and obturated with thermoplasticized injectable gutta-percha (Obtura II) using two sealers (Sealapex vs.AH plus). After immersing the teeth in 2.0% methylene blue, they were split longitudinally, viewed under light microscope (magnification X4) and images were taken by a camera connected to microscope. The extent of dye penetration was assessed from apex to its coronal part and recorded in millimeters. Independent sample t-test was used to compare microleakage in the two groups. Pearson correlation coefficient was used for inter-examiner reliability of dye penetration measurements. A p-value of <0.05 was taken as statistically significant. Results:Teeth obturated with Obtura II gutta-percha with AH plus sealer had a mean dye penetration of 1.20 +- 0.79 mm. This was significantly better than Obtura II with Sealapex sealer (p=0.003). Conclusion:Obtura II-AH plus sealer was a better combination for obturation as it showed a lesser degree of microleakage. Obtura II with Sealapex group showed higher microleakage, so this combination should be avoided in single-rooted teeth. (author)

Mounting ground sections of teeth: Cyanoacrylate adhesive versus Canada balsam.

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Vangala, Manogna Rl; Rudraraju, Amrutha; Subramanyam, R V

2016-01-01

Hard tissues can be studied by either decalcification or by preparing ground sections. Various mounting media have been tried and used for ground sections of teeth. However, there are very few studies on the use of cyanoacrylate adhesive as a mounting medium. The aim of our study was to evaluate the efficacy of cyanoacrylate adhesive (Fevikwik™) as a mounting medium for ground sections of teeth and to compare these ground sections with those mounted with Canada balsam. Ground sections were prepared from twenty extracted teeth. Each section was divided into two halves and mounted on one slide, one with cyanoacrylate adhesive (Fevikwik™) and the other with Canada balsam. Scoring for various features in the ground sections was done by two independent observers. Statistical analysis using Student's t-test (unpaired) of average scores was performed for each feature observed. No statistically significant difference was found between the two for most of the features. However, cyanoacrylate was found to be better than Canada balsam for observing striae of Retzius (P < 0.0205), enamel lamellae (P < 0.036), dentinal tubules (P < 0.0057), interglobular dentin (P < 0.0001), sclerotic dentin - transmitted light (P < 0.00001), sclerotic dentin - polarized light (P < 0.0002) and Sharpey's fibers (P < 0.0004). This initial study shows that cyanoacrylate is better than Canada balsam for observing certain features of ground sections of teeth. However, it remains to be seen whether it will be useful for studying undecalcified sections of carious teeth and for soft tissue sections.

Syndromes with supernumerary teeth.

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Lubinsky, Mark; Kantaputra, Piranit Nik

2016-10-01

While most supernumerary teeth are idiopathic, they can be associated with a number of Mendelian syndromes. However, this can also be a coincidental finding, since supernumerary teeth occur in 6% or more of the normal population. To better define this relationship, we analyzed the evidence for specific associations. We excluded conditions with a single affected patient reported, supernumerary teeth adjacent to clefts or other forms of alveolar disruption (as secondary rather than primary findings), and natal teeth, which can involve premature eruption of a normal tooth. Since, the cause of supernumerary teeth shows considerable heterogeneity, certain findings are less likely to be coincidental, such as five or more supernumerary teeth in a single patient, or locations outside of the premaxilla. We found only eight genetic syndromes with strong evidence for an association: cleidocranial dysplasia; familial adenomatous polyposis; trichorhinophalangeal syndrome, type I; Rubinstein-Taybi syndrome; Nance-Horan syndrome; Opitz BBB/G syndrome; oculofaciocardiodental syndrome; and autosomal dominant Robinow syndrome. There is also suggestive evidence of an association with two uncommon disorders, Kreiborg-Pakistani syndrome (craniosynostosis and dental anomalies), and insulin-resistant diabetes mellitus with acanthosisnigricans. An association of a Mendelian disorder with a low frequency manifestation of supernumerary teeth is difficult to exclude without large numbers, but several commonly cited syndromes lacked evidence for clear association, including Hallermann-Streiff syndrome, Fabry disease, Ehlers-Danlos syndrome, Apert and Crouzon syndromes, Zimmermann-Laband syndrome, and Ellis-van Creveld syndrome. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Supragingival Microbial Profiles of Permanent and Deciduous Teeth in Children with Mixed Dentition.

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Weihua Shi

Full Text Available The present study was designed to investigate the microbial profiles of teeth in different locations in mixed-dentition-stage children, and to compare the microbiomes of permanent and deciduous teeth in the same healthy oral cavity.Supragingival plaque samples of teeth in various locations-the first permanent molars, deciduous molars, deciduous canines and incisors and permanent incisors-were collected from 20 healthy mixed-dentition-stage children with 10-12 permanent teeth erupted. Plaque DNA was extracted, and the V3-V4 hypervariable region of the bacterial 16S rRNA gene was amplified and subjected to sequencing.On average, 18,051 high-quality sequences per sample were generated. Permanent tooth sites tended to host more diverse bacterial communities than those of deciduous tooth sites. A total of 12 phyla, 21 classes, 38 orders, 66 families, 74 genera were detected ultimately. Five predominant phyla (Proteobacteria, Firmicutes, Bacteroidetes, Fusobacteria and Actinobacteria were highly variable among sites. Of 26 genera with a mean relative abundance of >0.1%, 16 showed significant differences in relative abundance among the groups. More than 20% of the total operational taxonomical units were detected only in permanent or deciduous teeth. The variation in the microbial community composition was due mainly to permanent teeth being enriched in Actinomyces and deciduous teeth in Treponema. The core microbiome of supragingival plaque in mixed dentition comprised 19 genera with complex correlationships.Our results suggest differences in microbial diversity and composition between permanent and deciduous teeth sites in mixed dentition. Moreover, the core microbiome of these sites was determined. These findings enhance our understanding of the development of the native oral microbiota with age.

Management of third molar teeth from an endodontic perspective

OpenAIRE

Hany Mohamed Aly Ahmed

2012-01-01

Third molar teeth are subject to many dental complications because of their most posterior location, aberrant occlusal anatomy and abnormal eruption patterns. Owing to these anatomical limitations, their extraction remains the treatment of choice for many dental practitioners. Despite being a common dental procedure, minimum intervention and retaining every functional component of the dental arch are of prime importance in contemporary dental practice. As such, this review aims to discuss the...

Structural deformities of deciduous teeth in patients with hypophosphatemic vitamin D-resistant rickets

International Nuclear Information System (INIS)

Abe, K.; Ooshima, T.; Lily, T.S.; Yasufuku, Y.; Sobue, S.

1988-01-01

Structural deformities of deciduous teeth from patients with hypophosphatemic vitamin D-resistant rickets (HVDRR) (1 male and 2 female patients) were examined by means of transmitted light microscopy, contact microradiography, and x-ray microanalysis. Freshly extracted teeth were fixed in formalin and subsequently hemisected longitudinally through the midline. One half was prepared for ground sections and the other half for decalcified sections. Neither gross nor microscopic abnormalities were present in enamel of patients with HVDRR. The concentration of calcium and phosphorus and the calcium/phosphorus ratio of the enamel of patients with HVDRR were nearly equal to those of normal teeth, although the degree of radiopacity was less in HVDRR. On the other hand, numerous microscopic abnormalities in the dentin of patients with HVDRR were found, such as interglobular dentin, wide predentin zones, and tubular defects. The concentration of phosphorus in the dentin of a patient with familial HVDRR was extremely low. Furthermore, formation of reparative dentin was observed at the pulp horn of teeth in patients with HVDRR that had been subjected to definite attrition at the corresponding dentin site

Do sensation differences exist between dental implants and natural teeth?: a meta-analysis.

Science.gov (United States)

Higaki, Nobuaki; Goto, Takaharu; Ishida, Yuichi; Watanabe, Megumi; Tomotake, Yoritoki; Ichikawa, Tetsuo

2014-11-01

The purpose of this systematic review was to survey evidence pertaining to the sensation differences between natural teeth and osseointegrated dental implants. Using the MEDLINE (online PubMed) database, Cochrane Library, and Scientific Citation index, we performed a systematic search of articles. We used the following search terms: "perception or sensation and dental implant." The systematic review of the extracted articles was performed to see the sensation differences between natural teeth and dental implants. A total of six studies on oral sensation, "tactile sensibility," and "thickness discrimination" were included in the meta-analysis. As to the "tactile sensibility", all studies indicated the threshold levels of the implants were about 4-20 times higher than that of natural teeth. The tactile sensibility of an implant was significantly higher than that of a natural tooth, with an standardized mean difference (SMD) of 8.3619 (95% CI, 6.3920-10.3317) and a P sensation differences between dental implants and natural teeth exist. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

The prevalence of secondary dentinal lesions in cheek teeth from horses with clinical signs of pulpitis compared to controls.

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Casey, M B; Tremaine, W H

2010-01-01

With the advent of detailed oral examination in horses using dental mirrors and rigid endoscopy, secondary dentinal lesions are observed more frequently. More information regarding the association of secondary dentinal defects with apical dental disease would improve the sensitivity of oral examination as a diagnostic aid for pulpitis. To assess prevalence and severity of secondary dentinal defects observed on examination of occlusal surfaces of cheek teeth (CT) from horses showing clinical signs of pulpitis compared to asymptomatic controls. Records from all cases of equine CT exodontia at the University of Bristol over a 4 year period were examined. Case selection criteria included the presence of clinical signs of pulpitis, an intact extracted tooth and availability of a complete history and follow up. Cases where coronal fracture or periodontal pocketing featured were excluded. CT from cadavers with no history of dental disease served as normal controls. Triadan positions and eruption ages of control teeth were matched with those of teeth extracted from cases. CT from selected cases and control teeth were examined occlusally. Secondary dentinal defects were identified and graded. Prevalence of occlusal lesions in CT with pulpitis and controls was compared. From the records of 120 horses where exodontia was performed, 40 cases matched selection criteria. Twenty-three mandibular and 21 maxillary CT were extracted from cases. The controls consisted of 60 mandibular and 60 maxillary CT from 7 cadaver skulls. Secondary dentinal defects were significantly over-represented in CT extracted from cases of pulpitis (P pulpitis in equine CT.

Decellularized Human Dental Pulp as a Scaffold for Regenerative Endodontics.

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Song, J S; Takimoto, K; Jeon, M; Vadakekalam, J; Ruparel, N B; Diogenes, A

2017-06-01

Teeth undergo postnatal organogenesis relatively late in life and only complete full maturation a few years after the crown first erupts in the oral cavity. At this stage, development can be arrested if the tooth organ is damaged by either trauma or caries. Regenerative endodontic procedures (REPs) are a treatment alternative to conventional root canal treatment for immature teeth. These procedures rely on the transfer of apically positioned stem cells, including stem cells of the apical papilla (SCAP), into the root canal system. Although clinical success has been reported for these procedures, the predictability of expected outcomes and the organization of the newly formed tissues are affected by the lack of an available suitable scaffold that mimics the complexity of the dental pulp extracellular matrix (ECM). In this study, we evaluated 3 methods of decellularization of human dental pulp to be used as a potential autograft scaffold. Tooth slices of human healthy extracted third molars were decellularized by 3 different methods. One of the methods generated the maximum observed decellularization with minimal impact on the ECM composition and organization. Furthermore, recellularization of the scaffold supported the proliferation of SCAP throughout the scaffold with differentiation into odontoblast-like cells near the dentinal walls. Thus, this study reports that human dental pulp from healthy extracted teeth can be successfully decellularized, and the resulting scaffold supports the proliferation and differentiation of SCAP. The future application of this form of an autograft in REPs can fulfill a yet unmet need for a suitable scaffold, potentially improving clinical outcomes and ultimately promoting the survival and function of teeth with otherwise poor prognosis.

Performance of a gaseous detector based energy dispersive X-ray fluorescence imaging system: Analysis of human teeth treated with dental amalgam

International Nuclear Information System (INIS)

Silva, A.L.M.; Figueroa, R.; Jaramillo, A.; Carvalho, M.L.; Veloso, J.F.C.A.

2013-01-01

Energy dispersive X-ray fluorescence (EDXRF) imaging systems are of great interest in many applications of different areas, once they allow us to get images of the spatial elemental distribution in the samples. The detector system used in this study is based on a micro patterned gas detector, named Micro-Hole and Strip Plate. The full field of view system, with an active area of 28 × 28 mm 2 presents some important features for EDXRF imaging applications, such as a position resolution below 125 μm, an intrinsic energy resolution of about 14% full width at half maximum for 5.9 keV X-rays, and a counting rate capability of 0.5 MHz. In this work, analysis of human teeth treated by dental amalgam was performed by using the EDXRF imaging system mentioned above. The goal of the analysis is to evaluate the system capabilities in the biomedical field by measuring the drift of the major constituents of a dental amalgam, Zn and Hg, throughout the tooth structures. The elemental distribution pattern of these elements obtained during the analysis suggests diffusion of these elements from the amalgam to teeth tissues. - Highlights: • Demonstration of an EDXRF imaging system based on a 2D-MHSP detector for biological analysis • Evaluation of the drift of the dental amalgam constituents, throughout the teeth • Observation of Hg diffusion, due to hydroxyapatite crystal defects that compose the teeth tissues

Performance of a gaseous detector based energy dispersive X-ray fluorescence imaging system: Analysis of human teeth treated with dental amalgam

Energy Technology Data Exchange (ETDEWEB)

Silva, A.L.M. [I3N, Physics Dept, University of Aveiro, 3810-193 Aveiro (Portugal); Figueroa, R.; Jaramillo, A. [Physics Department, Universidad de La Frontera, Temuco (Chile); Carvalho, M.L. [Atomic Physics Centre, University of Lisbon, 1649-03 Lisboa (Portugal); Veloso, J.F.C.A., E-mail: joao.veloso@ua.pt [I3N, Physics Dept, University of Aveiro, 3810-193 Aveiro (Portugal)

2013-08-01

Energy dispersive X-ray fluorescence (EDXRF) imaging systems are of great interest in many applications of different areas, once they allow us to get images of the spatial elemental distribution in the samples. The detector system used in this study is based on a micro patterned gas detector, named Micro-Hole and Strip Plate. The full field of view system, with an active area of 28 × 28 mm{sup 2} presents some important features for EDXRF imaging applications, such as a position resolution below 125 μm, an intrinsic energy resolution of about 14% full width at half maximum for 5.9 keV X-rays, and a counting rate capability of 0.5 MHz. In this work, analysis of human teeth treated by dental amalgam was performed by using the EDXRF imaging system mentioned above. The goal of the analysis is to evaluate the system capabilities in the biomedical field by measuring the drift of the major constituents of a dental amalgam, Zn and Hg, throughout the tooth structures. The elemental distribution pattern of these elements obtained during the analysis suggests diffusion of these elements from the amalgam to teeth tissues. - Highlights: • Demonstration of an EDXRF imaging system based on a 2D-MHSP detector for biological analysis • Evaluation of the drift of the dental amalgam constituents, throughout the teeth • Observation of Hg diffusion, due to hydroxyapatite crystal defects that compose the teeth tissues.

[The social value of teeth and access to dental health services].

Science.gov (United States)

Fonseca, Luciara Leão Viana; Nehmy, Rosa Maria Quadros; Mota, Joaquim Antônio César

2015-10-01

Oral healthcare provided by the Unified Health System (SUS) faces the challenge of attending the epidemiological profile of Brazil's adult population. Qualitative research using semi-structured interviews was conducted to understand the experiences, expectations and perception of SUS users to services in Diamantina, State of Minas Gerais, and content analysis was used to assess the data. Discussion of the results was based on dialogue between the symbolic interactionism of Goffman and Bourdieu's concept of habitus. The results show that the users did not give importance to dental care during childhood and adolescence because care was unknown to them. There was no offer of treatment besides dental extraction. Today, they value teeth and suffer the embarrassment caused by rotten teeth. However, access to dental restoration via SUS is not possible. For their children, they perceive better access to information and care, but for specialized procedures there are barriers. They express resignation both in relation to the poor state of the teeth and the difficulties of access to dental care, which can be understood by the constant exclusion experienced by them in the past, shaping their actions in the present. It was concluded that oral health in SUS should incorporate the social value and the aesthetic dimension of teeth as a social right.

Biomechanical considerations in mandibular incisor extraction cases.

Science.gov (United States)

Rachala, Madhukar Reddy; Aileni, Kaladhar Reddy; Dasari, Arun Kumar; Sinojiya, Jay

2015-01-01

Mandibular incisor extraction can be regarded as a valuable treatment option in certain malocclusions to obtain excellence in orthodontic results in terms of function, aesthetics and stability. This treatment alternative is indicated in clinical situations like mild to moderate class III malocclusion, mild anterior mandibular tooth size excess, periodontally compromised teeth, ectopic eruption of mandibular incisor and minimal openbite tendencies. Unlike in premolar extraction cases, space closure in mandibular incisor extraction cases is unique in which the extraction space will be in the middle of the arch. The end result of space closure in these cases should be well aligned, upright, anterior teeth with parallel roots and the goal can be achieved with the bodily tooth movement through proper application of biomechanics. The purpose of this article is to explain the biomechanics of space closure in mandibular incisor extraction cases.

DNA and bone structure preservation in medieval human skeletons.

Science.gov (United States)

Coulson-Thomas, Yvette M; Norton, Andrew L; Coulson-Thomas, Vivien J; Florencio-Silva, Rinaldo; Ali, Nadir; Elmrghni, Samir; Gil, Cristiane D; Sasso, Gisela R S; Dixon, Ronald A; Nader, Helena B

2015-06-01

Morphological and ultrastructural data from archaeological human bones are scarce, particularly data that have been correlated with information on the preservation of molecules such as DNA. Here we examine the bone structure of macroscopically well-preserved medieval human skeletons by transmission electron microscopy and immunohistochemistry, and the quantity and quality of DNA extracted from these skeletons. DNA technology has been increasingly used for analyzing physical evidence in archaeological forensics; however, the isolation of ancient DNA is difficult since it is highly degraded, extraction yields are low and the co-extraction of PCR inhibitors is a problem. We adapted and optimised a method that is frequently used for isolating DNA from modern samples, Chelex(®) 100 (Bio-Rad) extraction, for isolating DNA from archaeological human bones and teeth. The isolated DNA was analysed by real-time PCR using primers targeting the sex determining region on the Y chromosome (SRY) and STR typing using the AmpFlSTR(®) Identifiler PCR Amplification kit. Our results clearly show the preservation of bone matrix in medieval bones and the presence of intact osteocytes with well preserved encapsulated nuclei. In addition, we show how effective Chelex(®) 100 is for isolating ancient DNA from archaeological bones and teeth. This optimised method is suitable for STR typing using kits aimed specifically at degraded and difficult DNA templates since amplicons of up to 250bp were successfully amplified. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Fracture resistance and histological findings of immature teeth treated with mineral trioxide aggregate

DEFF Research Database (Denmark)

Hatibovic-Kofman, S.; Raimundo, L.; Zheng, L.

2008-01-01

The objective of the present study was to test the hypothesis that the fracture strength of calcium hydroxide and mineral trioxide aggregate (MTA)-filled immature teeth decreased over time. Immature mandibular incisors from sheep were extracted and the pulps were extirpated using an apical approach...

Bacterial profile in primary teeth with necrotic pulp and periapical lesions.

Science.gov (United States)

da Silva, Léa Assed Bezerra; Nelson-Filho, Paulo; Faria, Gisele; de Souza-Gugelmin, Maria Cristina Monteiro; Ito, Izabel Yoko

2006-01-01

The objective of this study was to evaluate the bacterial profile in root canals of human primary teeth with necrotic pulp and periapical lesions using bacterial culture. A total of 20 primary teeth with necrotic pulp and radiographically visible radiolucent areas in the region of the bone furcation and/or the periapical region were selected. After crown access, 4 sterile absorbent paper points were introduced sequentially into the root canal for collection of material. After 30 s, the paper points were removed and placed in a test tube containing reduced transport fluid (RTF) and were sent for microbiological evaluation. Anaerobic microorganisms were found in 100% of the samples, black-pigmented bacilli in 30%, aerobic microorganisms in 60%, streptococci in 85%, gram-negative aerobic rods in 15% and staphylococci were not quantified. Mutans streptococci were found in 6 root canals (30%), 5 canals with Streptococcus mutans and 1 canal with Streptococcus mutans and Streptococcus sobrinus. It was concluded that in root canals of human primary teeth with necrotic pulp and periapical lesions, the infection is polymicrobial with predominance of anaerobic microorganisms.

Hominin teeth from the Middle Pleistocene site of Yiyuan, Eastern China.

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Xing, Song; Sun, Chengkai; Martinón-Torres, María; Bermúdez de Castro, José María; Han, Fei; Zhang, Yingqi; Liu, Wu

2016-06-01

In 1981-1982, some hominin fossils, including a relatively complete skull and seven isolated teeth, were recovered from the Middle Pleistocene site of Yiyuan in Eastern China. In the present study we provide a detailed metric and morphological comparison of the Yiyuan dental sample in order to characterize better the variability of the human populations that inhabited China during the Middle Pleistocene. Aside from taxonomic and phylogenetic questions, the lack of understanding and/or knowledge about the morphological variability of these populations have caused concern about the human versus non-human nature of some of the hominin dental remains found in East Asia during the Early and the Middle Pleistocene. Thus, our study aims to present a detailed description and comparison of the Yiyuan isolated teeth to 1) discuss and support their human nature and 2) to explore their taxonomic affinities with regard to other penecontemporaneous populations from Asia. Our results clearly differentiate the Yiyuan sample from Pongo specimens and support a human attribution for the Yiyuan material. Our analyses also suggest that the Yiyuan teeth form a morphologically coherent group together with samples from Zhoukoudian, Chaoxian and Hexian. They are different from the more derived specimens from Panxian Dadong, suggesting a pattern of biogeographic isolation and different evolutionary trends between northern and southern China during the Middle Pleistocene. In addition, and despite sharing a common morphological bauplan with Homo erectus sensu stricto (s.s.), the Yiyuan, Zhoukoudian and Hexian teeth are also different from the Indonesian Early Pleistocene samples. In particular, the expression of a highly crenulated or dendritic enamel-dentine surface could be unique to these groups. Our study supports the notion that the taxonomy of the Pleistocene hominins from Asia may have been oversimplified. Future studies should explore the variability of the Asian specimens and

Electron spin resonance dating of human teeth from Toca da Santa shelter of Sao Raimundo Nonato, Piaui, Brazil

Energy Technology Data Exchange (ETDEWEB)

Kinoshita, A. [Faculdade de Filosofia, Ciencias e Letras de Ribeirao Preto, Universidade de Sao Paulo, Av. Bandeirantes, 3900, 14040-901 Ribeirao Preto, SP (Brazil); Universidade do Sagrado Coracao, Rua Irma Arminda 10-50, 17011-160 Bauru, SP (Brazil); Figueiredo, A.M.G. [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Av. Lineu Prestes, 2242, Cidade Universitaria, 5422-970 Sao Paulo, SP (Brazil); Felice, G.D. [Fundacao Museu do Homem Americano-FUNDHAM, Rua Abdias Neves, no. 551, Centro, 64770-000 Sao Raimundo Nonato, Piaui (Brazil); Lage, M.C.S.M. [Universidade Federal do Piaui, Departamento de Quimica, Campus da Ininga, Ininga, 64049-550 Teresina, Piaui (Brazil); Guidon, N. [Fundacao Museu do Homem Americano-FUNDHAM, Rua Abdias Neves, no. 551, Centro, 64770-000 Sao Raimundo Nonato, Piaui (Brazil); Baffa, O. [Faculdade de Filosofia, Ciencias e Letras de Ribeirao Preto, Universidade de Sao Paulo, Av. Bandeirantes, 3900, 14040-901 Ribeirao Preto, SP (Brazil)], E-mail: baffa@usp.br

2008-02-15

Results of the dating of fossil human teeth excavated from a shelter in the surroundings areas of the Serra da Capivara National Park, Sao Raimundo Nonato, Piaui, Brazil are presented. This shelter was partially excavated to search for more data that could improve the archaeological context of the Garrincho's limestone hill sites, where the Toca do Gordo do Garrincho shelter provided two human teeth dated by conventional C-14 in (12,170 {+-} 40) yBP (years before present) and calibrated age (2 Sigma, 95% probability) 15,245-14,690 yBP (Beta 136204) [E. Peyre, C. Guerin, N. Guidon, I. Coppens, CR Acad. Sci. Paris, Sciences de la terre et des planetes/ Earth and Planetary Sciences 327 (1998) 335, ]. This region is challenging the classical theories about the peopling of America. In agreement with such theories the first human groups would have arrived in America, through Behring, only about 20,000 years ago. The site Toca do Boqueirao da Pedra Furada is a rock-shelter situated at the cliff that is the frontier between the Pre-Cambrian Sao Francisco plain and the Devonian-Permian highlands of the Maranhao-Piaui basin. It was excavated from 1978 till 1988 and presented a very consistent stratigraphy, with thousand of lithic implements and hearths [F. Parenti, Le gisement quaternaire de la Pedra Furada (Piaui, Bresil), Stratigraphie, chronologie, evolution culturelle, Editions Recherches sur les civilisations, Paris, 2002, ; F. Parenti, Le Gisement Quaternaire de la Toca do Boqueirao da Pedra Furada (Piaui, Bresil) dans le Contexte de la Prehistoire Americaine Fouilles, Stratigraphie, Chronologie, Evolution Culturelle, Ph.D. diss, Ecole des Hautes Etudes en Sciences Sociales, Paris, 1993, 411p, ; F. Parenti, M. Fontugne, N. Guidon, C. Guerin, M. Faure, Chronostratigraphie des gisements archeologiques et paleontologiques de Sao Raimundo Nonato (Piaui, Bresil): contribution a la connaissance du peuplement pleistocene de l'Amerique, Supplement de la Revue d

Electron spin resonance dating of human teeth from Toca da Santa shelter of Sao Raimundo Nonato, Piaui, Brazil

International Nuclear Information System (INIS)

Kinoshita, A.; Figueiredo, A.M.G.; Felice, G.D.; Lage, M.C.S.M.; Guidon, N.; Baffa, O.

2008-01-01

Results of the dating of fossil human teeth excavated from a shelter in the surroundings areas of the Serra da Capivara National Park, Sao Raimundo Nonato, Piaui, Brazil are presented. This shelter was partially excavated to search for more data that could improve the archaeological context of the Garrincho's limestone hill sites, where the Toca do Gordo do Garrincho shelter provided two human teeth dated by conventional C-14 in (12,170 ± 40) yBP (years before present) and calibrated age (2 Sigma, 95% probability) 15,245-14,690 yBP (Beta 136204) [E. Peyre, C. Guerin, N. Guidon, I. Coppens, CR Acad. Sci. Paris, Sciences de la terre et des planetes/ Earth and Planetary Sciences 327 (1998) 335, ]. This region is challenging the classical theories about the peopling of America. In agreement with such theories the first human groups would have arrived in America, through Behring, only about 20,000 years ago. The site Toca do Boqueirao da Pedra Furada is a rock-shelter situated at the cliff that is the frontier between the Pre-Cambrian Sao Francisco plain and the Devonian-Permian highlands of the Maranhao-Piaui basin. It was excavated from 1978 till 1988 and presented a very consistent stratigraphy, with thousand of lithic implements and hearths [F. Parenti, Le gisement quaternaire de la Pedra Furada (Piaui, Bresil), Stratigraphie, chronologie, evolution culturelle, Editions Recherches sur les civilisations, Paris, 2002, ; F. Parenti, Le Gisement Quaternaire de la Toca do Boqueirao da Pedra Furada (Piaui, Bresil) dans le Contexte de la Prehistoire Americaine Fouilles, Stratigraphie, Chronologie, Evolution Culturelle, Ph.D. diss, Ecole des Hautes Etudes en Sciences Sociales, Paris, 1993, 411p, ; F. Parenti, M. Fontugne, N. Guidon, C. Guerin, M. Faure, Chronostratigraphie des gisements archeologiques et paleontologiques de Sao Raimundo Nonato (Piaui, Bresil): contribution a la connaissance du peuplement pleistocene de l'Amerique, Supplement de la Revue d

Effect of aquatine endodontic cleanser on smear layer removal in the root canals of ex vivo human teeth

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Faustino Garcia

2010-08-01

Full Text Available OBJECTIVES: The purpose of this study was to measure and compare the root canal cleanliness and smear layer removal effectiveness of Aquatine Endodontic Cleanser (Aquatine EC when used as an endodontic irrigating solution in comparison with 6% sodium hypochlorite (NaOCl. MATERIAL AND METHODS: Forty-five human teeth were randomly allocated to five treatment groups; the pulp chamber was accessed, cleaned, and shaped by using ProTaper and ProFile rotary instrumentation to an ISO size #40. The teeth were then processed for scanning electron microscopy, and the root canal cleanliness and removal of smear layer were examined. RESULTS: The most effective removal of smear layer occurred with Aquatine EC and NaOCl, both with a rinse of EDTA. CONCLUSIONS: Aquatine EC appears to be the first hypochlorous acid approved by the FDA to be a possible alternative to the use of NaOCl as an intracanal irrigant. Further research is needed to identify safer and more effective alternatives to the use of NaOCl irrigation in endodontics.

In vitro study of heat production during power reduction of equine mandibular teeth.

Science.gov (United States)

Allen, Martin L; Baker, Gordon J; Freeman, David E; Holmes, Kenneth R; Marretta, Sandra Manfra; Scoggins, R Dean; Constable, Peter

2004-04-01

To measure the amount of heat generated during 3 methods of equine dental reduction with power instruments. In vitro study. 30 premolar and molar teeth removed from mandibles of 8 equine heads collected at an abbatoir. 38-gauge copper-constantan thermocouples were inserted into the lingual side of each tooth 15 mm (proximal) and 25 mm (distal) from the occlusal surface, at a depth of 5 mm, which placed the tip close to the pulp chamber. Group-NC1 (n = 10) teeth were ground for 1 minute without coolant, group-NC2 (10) teeth were ground for 2 minutes without coolant, and group-C2 (10) teeth were ground for 2 minutes with water for coolant. Mean temperature increase was 1.2 degrees C at the distal thermocouple and 6.6 degrees C at the proximal thermocouple for group-NC1 teeth, 4.1 degrees C at the distal thermocouple and 24.3 degrees C at the proximal thermocouple for group-NC2 teeth, and 0.8 degrees C at the distal thermocouple and -0.1 degrees C at the proximal thermocouple for group-C2 teeth. In general, an increase of 5 degrees C in human teeth is considered the maximum increase before there is permanent damage to tooth pulp. In group-NC2 teeth, temperature increased above this limit by several degrees, whereas in group-C2 teeth, there was little or no temperature increase. Our results suggest that major reduction of equine teeth by use of power instruments causes thermal changes that may cause irreversible pulp damage unless water cooling is used.

Supernumerary teeth in non-syndromic patients

International Nuclear Information System (INIS)

Mali, Santosh; Karjodkar, Freny Rashmiraj; Sontakke, Subodh; Sansare, Kaustubh

2012-01-01

Hyperdontia or supernumerary teeth without associated syndrome is a rare phenomenon, as supernumerary teeth are usually associated with cleft lip and palate or other syndromes such as Gardner's syndrome, cleidocranial dysplasia, and so on. Five patients with supernumerary teeth visited our department. They had no familial history or other pathology, certain treatment protocols was modified due to the presence of supernumerary teeth. Non-syndromic supernumerary teeth, if asymptomatic, need to have periodical radiographic observation. If they showed no variation as they impacted in the jaw, careful examination is necessary because they may develop into pathological status such as dentigerous cysts. The importance of a precise clinical history and radiographic examination for patients with multiple supernumerary teeth should be emphasized.

An Evo-Devo perspective on ever-growing teeth in mammals and dental stem cell maintenance

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Elodie eRenvoisé

2014-08-01

Full Text Available A major challenge for current evolutionary and developmental biology research is to understand the evolution of morphogenesis and the mechanisms involved. Teeth are well suited for the investigation of developmental processes. In addition, since teeth are composed of hard-mineralized tissues, primarily apatite, that are readily preserved, the evolution of mammals is well documented through their teeth in the fossil record. Hypsodonty, high crowned teeth with shallow roots, and hypselodonty, ever-growing teeth, are convergent innovations that have appeared multiple times since the mammalian radiation 65 million years ago, in all tooth categories (incisors, canines, premolars and molars. A shift to hypsodonty, or hypselodonty, during mammalian evolution is often, but not necessarily, associated with increasingly abrasive diet during important environmental change events. Although the evolution of hypsodonty and hypselodonty is considered to be the result of heterochrony of development, little has been known about the exact developmental mechanisms at the origin of these morphological traits. Developmental biologists have been intrigued by the mechanism of hypselodonty since it requires the maintenance of continuous crown formation during development via stem cell niche activity. Understanding this mechanism may allow bioengineered tooth formation in humans. Hypsodonty and hypselodonty are thus examples of phenotypic features of teeth that have both impacts in understanding the evolution of mammals and holds promise for human tooth bioengineering.

The effect of Emdogain and 24% EDTA root conditioning on periodontal healing of replanted dog's teeth.

Science.gov (United States)

Guzmán-Martínez, Nayelli; Silva-Herzog, Flores Daniel; Méndez, González Verónica; Martín-Pérez, Silvia; Cerda-Cristerna, Bernardino Isaac; Cohenca, Nestor

2009-02-01

Controversies still exist as for the regenerative role of enamel matrix derivatives and the need for removal of the periodontal ligament in replanted teeth. The purpose of this study was to evaluate the effect of Emdogain and 24% ethylenediamine tetraacetic acid (EDTA) root conditioning on periodontal healing of replanted dog's teeth. Teeth were extracted, endodontically treated and preconditioned as follows: group 1, Emdogain; group 2, Emdogain + EDTA and group 3, EDTA. Teeth were replanted after 30 min extraoral time, splinted for 15 days and animals sacrificed after 8 weeks of observation. Histological evaluation was performed using hematoxylin/eosin and Masson trichrome and results scored based on previously reported criteria for histological evaluation. Replacement root resorption was histologically diagnosed in all groups except in the negative control. A parametric analysis showed no statistically significant differences between experimental groups. Root preconditioning with Emdogain alone or in combination with 24% EDTA showed no evidence of regeneration of collagen fibers and consequently did not prevent the development of replacement root resorption on replanted dog's teeth.

Supernumerary teeth in non-syndromic patients

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Mali, Santosh; Karjodkar, Freny Rashmiraj; Sontakke, Subodh; Sansare, Kaustubh [Nair Hospital Dental College, Maharashtra (India)

2012-03-15

Hyperdontia or supernumerary teeth without associated syndrome is a rare phenomenon, as supernumerary teeth are usually associated with cleft lip and palate or other syndromes such as Gardner's syndrome, cleidocranial dysplasia, and so on. Five patients with supernumerary teeth visited our department. They had no familial history or other pathology, certain treatment protocols was modified due to the presence of supernumerary teeth. Non-syndromic supernumerary teeth, if asymptomatic, need to have periodical radiographic observation. If they showed no variation as they impacted in the jaw, careful examination is necessary because they may develop into pathological status such as dentigerous cysts. The importance of a precise clinical history and radiographic examination for patients with multiple supernumerary teeth should be emphasized.

Aloe vera extract activity on human corneal cells.

Science.gov (United States)

Woźniak, Anna; Paduch, Roman

2012-02-01

Ocular diseases are currently an important problem in modern societies. Patients suffer from various ophthalmologic ailments namely, conjunctivitis, dry eye, dacryocystitis or degenerative diseases. Therefore, there is a need to introduce new treatment methods, including medicinal plants usage. Aloe vera [Aloe barbadensis Miller (Liliaceae)] possesses wound-healing properties and shows immunomodulatory, anti-inflammatory or antioxidant activities. NR uptake, MTT, DPPH• reduction, Griess reaction, ELISA and rhodamine-phalloidin staining were used to test toxicity, antiproliferative activity, reactive oxygen species (ROS) reduction, nitric oxide (NO) and cytokine level, and distribution of F-actin in cells, respectively. The present study analyzes the effect of Aloe vera extracts obtained with different solvents on in vitro culture of human 10.014 pRSV-T corneal cells. We found no toxicity of ethanol, ethyl acetate and heptane extracts of Aloe vera on human corneal cells. No ROS reducing activity by heptane extract and trace action by ethanol (only at high concentration 125 µg/ml) extract of Aloe vera was observed. Only ethyl acetate extract expressed distinct free radical scavenging effect. Plant extracts decreased NO production by human corneal cells as compared to untreated controls. The cytokine (IL-1β, IL-6, TNF-α and IL-10) production decreased after the addition of Aloe vera extracts to the culture media. Aloe vera contains multiple pharmacologically active substances which are capable of modulating cellular phenotypes and functions. Aloe vera ethanol and ethyl acetate extracts may be used in eye drops to treat inflammations and other ailments of external parts of the eye such as the cornea.

Assessment of endodontically treated teeth by using different radiographic methods: an ex vivo comparison between CBCT and other radiographic techniques

International Nuclear Information System (INIS)

Demiralp, Kemal Oeaguer; Uecok, Oezlem; Kamburoglu, Kivanc; Selcen Yuesel, Kahraman Guengoer; Demiralp, Gokcen

2012-01-01

To compare different radiographic methods for assessing endodontically treated teeth. Root canal treatments were applied in 120 extracted mandibular teeth, which were divided into four groups: (1) ideal root canal treatment (60 teeth), (2) insufficient lateral condensation (20 teeth), (3) root canals filled short of the apex (20 teeth), (4) overfilled root canal treatment (20 teeth). The teeth were imaged using intraoral film, panoramic film, digital intraoral systems (CCD and PSP), CCD obtained with portable X-ray source, digital panoramic, and CBCT images obtained at 0.3 mm 3 and 0.2 mm'3 voxel size. Images were evaluated separately by three observers, twice. Kappa coefficients were calculated. The percentage of correct readings obtained from each modality was calculated and compared using a t-test (p 3 voxel images revealed the best results. For insufficient lateral condensation, the best readings were found with periapical film followed by CCD and PSP. The assessment of teeth with root canals filled short of the apex showed the highest percentage of correct readings by CBCT and CCD. For the overfilled canal treatment group, PSP images and conventional periapical film radiographs had the best scores. CBCT was found to be successful in the assessment of teeth with ideal root canal treatment and teeth with canals filled short of the apex.

CORROSION IN ACIDIC BEVERAGES AND RECOVERY OF MICROHARDNESS OF HUMAN TEETH ENAMEL

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Petra Gaalova

2016-05-01

Full Text Available We studied the influence of corrosion in acidic beverages (white wine, pH~3.5 on micromechanical properties of human teeth. Simultaneously, the effect of fluorine-containing mouthwash (pH~4.4 and of artificial saliva (pH~5.3 in terms of their protective action against corrosion, and the recovery of mechanical properties through fluoridation and re-calcification was studied. The influence of the solutions on Vickers hardness of dental enamel was monitored on the basis of results from the corrosion tests carried out under quasi-dynamic conditions. The tests were performed at the temperature corresponding to the temperature of human body (37°C. The measurements confirmed a significant deterioration of microhardness with prolonged exposure to white wine. The Vickers hardness decreased from 347 HV0.2 in un-corroded specimens to 186 HV0.2 in samples corroded for 60 minutes in white wine. A recovery of Vickers hardness was observed after 60 minutes exposition time in the fluoridation solution, with the increase from 186 to 372 HV0.2. Similar effect was observed in the artificial saliva solution, with observed hardness increase from 186 to 320 HV0.2. Healing of corrosion-induced defects by the action of both solutions was observed by SEM, and associated with observed increase of hardness

Efficiency of Castor Oil as a Storage Medium for Avulsed Teeth in Maintaining the Viability of Periodontal Ligament Cells.

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Nabavizadeh, Mohammadreza; Abbaszadegan, Abbas; Khodabakhsi, Afrooz; Ahzan, Shamseddin; Mehrabani, Davood

2018-03-01

Researchers always seek a new storage medium for avulsed teeth. Castor oil is a vegetable oil with several advantages such as antimicrobial and antioxidant properties, low toxicity, and glutathione preservation capability, low cost, and high availability. The purpose of this study was to evaluate and compare the capacity of castor oil as a new storage medium in preserving the viability of periodontal ligament (PDL) cells compared to Hank's balanced salt solution (HBSS) and milk. Forty freshly extracted human teeth were divided into 3 experimental and 2 control groups. The experimental teeth were stored dry for 30 min and then immersed for 45 min in one of the following media; castor oil, HBSS, and milk. The positive and negative control groups were exposed to 0 min and 2 h of dry time respectively with no immersion in any storage medium. The teeth were then treated with dispase grade II and collagenase and the number of viable PDL cells were counted. Data were analyzed using Kruskal- Wallis test. The percentage of viable cells treated with castor oil, HBSS and milk counted immediately after removal from these media were 46.93, 51.02 and 55.10 % respectively. The statistical analysis revealed that the value for castor oil was significantly lower than HBSS and milk ( p > 0.05). Within the parameters of this study, it appears that castor oil cannot be served as an ideal medium for storage of avulsed tooth. More investigations under in vivo conditions are required to justify the results of this study.

The effects of NaF, Fluor-protector and Aminofluoride on the enamel of permanent teeth in children

OpenAIRE

Beloica, Dragan

1984-01-01

The effects of three fluor preparation (NaF, Fluor-Protector and Aminofluoride) on the enamel of permanent teeth has been studied by determinig the fluor concentrations in the enamel surface layer and the resistance of enamel to the effects of acids. The fluor preparations were applied to intact extracted teeth. Fluor concentrations were determined in the enamel samples using a Bedkman electrode with pH meter for fliuorides. Acid resistance was established by etching the enamnel samples, prev...

Single-Rooted Extraction Sockets: Classification and Treatment Protocol.

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El Chaar, Edgar; Oshman, Sarah; Fallah Abed, Pooria

2016-09-01

Clinicians have many treatment techniques from which to choose when extracting a failing tooth and replacing it with an implant-supported restoration and when successful management of an extraction socket during the course of tooth replacement is necessary to achieve predictable and esthetic outcomes. This article presents a straightforward, yet thorough, classification for extraction sockets of single-rooted teeth and provides guidance to clinicians in the selection of appropriate and predictable treatment. The presented classification of extraction sockets for single-rooted teeth focuses on the topography of the extraction socket, while the protocol for treatment of each socket type factors in the shape of the remaining bone, the biotype, and the location of the socket whether it be in the mandible or maxilla. This system is based on the biologic foundations of wound healing and can help guide clinicians to successful treatment outcomes.

Shark teeth as edged weapons: serrated teeth of three species of selachians.

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Moyer, Joshua K; Bemis, William E

2017-02-01

Prior to European contact, South Pacific islanders used serrated shark teeth as components of tools and weapons. They did this because serrated shark teeth are remarkably effective at slicing through soft tissues. To understand more about the forms and functions of serrated shark teeth, we examined the morphology and histology of tooth serrations in three species: the Tiger Shark (Galeocerdo cuvier), Blue Shark (Prionace glauca), and White Shark (Carcharodon carcharias). We show that there are two basic types of serrations. A primary serration consists of three layers of enameloid with underlying dentine filling the serration's base. All three species studied have primary serrations, although the dentine component differs (orthodentine in Tiger and Blue Sharks; osteodentine in the White Shark). Smaller secondary serrations are found in the Tiger Shark, formed solely by enameloid with no contribution from underlying dentine. Secondary serrations are effectively "serrations within serrations" that allow teeth to cut at different scales. We propose that the cutting edges of Tiger Shark teeth, equipped with serrations at different scales, are linked to a diet that includes large, hard-shelled prey (e.g., sea turtles) as well as smaller, softer prey such as fishes. We discuss other aspects of serration form and function by making analogies to man-made cutting implements, such as knives and saws. Copyright © 2016 Elsevier GmbH. All rights reserved.

Evaluation of apically extruded debris during root canal preparation in primary molar teeth using three different rotary systems and hand files.

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Topçuoğlu, Gamze; Topçuoğlu, Hüseyin Sinan; Akpek, Firdevs

2016-09-01

To assess the amount of debris extruded apically during root canal preparation using various nickel titanium instrumentation systems and hand files in primary molar teeth. Sixty extracted primary first mandibular molar human teeth were randomly assigned to four groups (n = 15 teeth for each group). The canals were then instrumented with the following instrument systems: Revo-S, Mtwo, ProTaper Next, and hand files. Apically extruded debris during instrumentation was collected into pre-weighed Eppendorf tubes. The Eppendorf tubes were then stored in an incubator at 70°C for 5 days. The weight of the dry extruded debris was established by subtracting the pre-instrumentation and post-instrumentation weight of the Eppendorf tubes for each group. The data were analyzed using one-way analysis of variance (anova) and Tukey's post hoc tests. ProTaper Next files were associated with less apically extruded debris than the Mtwo, Revo-S, and hand files (P Hand files extruded more debris than Mtwo and Revo-S instruments (P 0.05). All instruments were associated with apical extrusion of debris. ProTaper Next files caused less debris extrusion compared to the other systems used. © 2015 BSPD, IAPD and John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Multivariate analyses of small theropod dinosaur teeth and implications for paleoecological turnover through time.

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Derek W Larson

Full Text Available Isolated small theropod teeth are abundant in vertebrate microfossil assemblages, and are frequently used in studies of species diversity in ancient ecosystems. However, determining the taxonomic affinities of these teeth is problematic due to an absence of associated diagnostic skeletal material. Species such as Dromaeosaurus albertensis, Richardoestesia gilmorei, and Saurornitholestes langstoni are known from skeletal remains that have been recovered exclusively from the Dinosaur Park Formation (Campanian. It is therefore likely that teeth from different formations widely disparate in age or geographic position are not referable to these species. Tooth taxa without any associated skeletal material, such as Paronychodon lacustris and Richardoestesia isosceles, have also been identified from multiple localities of disparate ages throughout the Late Cretaceous. To address this problem, a dataset of measurements of 1183 small theropod teeth (the most specimen-rich theropod tooth dataset ever constructed from North America ranging in age from Santonian through Maastrichtian were analyzed using multivariate statistical methods: canonical variate analysis, pairwise discriminant function analysis, and multivariate analysis of variance. The results indicate that teeth referred to the same taxon from different formations are often quantitatively distinct. In contrast, isolated teeth found in time equivalent formations are not quantitatively distinguishable from each other. These results support the hypothesis that small theropod taxa, like other dinosaurs in the Late Cretaceous, tend to be exclusive to discrete host formations. The methods outlined have great potential for future studies of isolated teeth worldwide, and may be the most useful non-destructive technique known of extracting the most data possible from isolated and fragmentary specimens. The ability to accurately assess species diversity and turnover through time based on isolated teeth

Multivariate Analyses of Small Theropod Dinosaur Teeth and Implications for Paleoecological Turnover through Time

Science.gov (United States)

Larson, Derek W.; Currie, Philip J.

2013-01-01

Isolated small theropod teeth are abundant in vertebrate microfossil assemblages, and are frequently used in studies of species diversity in ancient ecosystems. However, determining the taxonomic affinities of these teeth is problematic due to an absence of associated diagnostic skeletal material. Species such as Dromaeosaurus albertensis, Richardoestesia gilmorei, and Saurornitholestes langstoni are known from skeletal remains that have been recovered exclusively from the Dinosaur Park Formation (Campanian). It is therefore likely that teeth from different formations widely disparate in age or geographic position are not referable to these species. Tooth taxa without any associated skeletal material, such as Paronychodon lacustris and Richardoestesia isosceles, have also been identified from multiple localities of disparate ages throughout the Late Cretaceous. To address this problem, a dataset of measurements of 1183 small theropod teeth (the most specimen-rich theropod tooth dataset ever constructed) from North America ranging in age from Santonian through Maastrichtian were analyzed using multivariate statistical methods: canonical variate analysis, pairwise discriminant function analysis, and multivariate analysis of variance. The results indicate that teeth referred to the same taxon from different formations are often quantitatively distinct. In contrast, isolated teeth found in time equivalent formations are not quantitatively distinguishable from each other. These results support the hypothesis that small theropod taxa, like other dinosaurs in the Late Cretaceous, tend to be exclusive to discrete host formations. The methods outlined have great potential for future studies of isolated teeth worldwide, and may be the most useful non-destructive technique known of extracting the most data possible from isolated and fragmentary specimens. The ability to accurately assess species diversity and turnover through time based on isolated teeth will help illuminate

Incidence of Radiographic Cystic Lesions Associated With Unerupted Teeth in Dogs.

Science.gov (United States)

Babbitt, Sam G; Krakowski Volker, Mary; Luskin, Ira R

2016-12-01

Medical records and radiographs were retrospectively reviewed over a 3-year period (2012-2015) from dogs presented to a private dental referral practice. Medical records were evaluated for the diagnosis of impacted or embedded teeth. The identified dogs' radiographs were reviewed for the presence of radiographically significant cystic lesions that were associated with the impacted or embedded teeth. Radiographic criteria were established by the authors for the purposes of identifying cystic lesions in dogs of different breeds and sizes, using established indices from human dental pathology as a basis. When histopathology results were available, they were reviewed and reported. In this study, 136 dogs ranging in age from 3 months to 17 years were diagnosed with 213 unerupted teeth during the study period. There were 62 (29.1%) of the 213 radiographically apparent cystic lesions identified based on the criteria proposed in this study. In this study, 146 (68.5%) of the 213 unerupted teeth were identified as mandibular first premolar teeth. Histopathology was obtained on 28 (45.1%) of the 62 diagnosed cystic lesions. Dentigerous cysts accounted for 20 (71.4%) of the 28 cystic lesions. Brachycephalic breeds were overrepresented in this study. Boxer, pug, Shih Tzu, and Boston terrier dogs were most likely to present with cystic lesions associated with unerupted teeth. Seventeen (85%) of the 20 cases with a histopathologic diagnosis of dentigerous cyst were found within these 4 brachycephalic breeds.

Endotoxin content in endodontically involved teeth. 1975.

Science.gov (United States)

Schein, Benjamin; Schilder, Herbert

2006-04-01

Fluid was aspirated from the root canals of 40 endodontically involved teeth. This fluid was assayed for endotoxin with the limulus lysate test. Pulpless teeth contained greater concentrations of endotoxin than those with vital pulps. Symptomatic teeth also contained more endotoxin than asymptomatic teeth.

Trace element analysis of blackish staining on the crowns of human archaeological teeth

Energy Technology Data Exchange (ETDEWEB)

Stermer, E.M. [Univ. of Oslo, Dept. of Oral Radiology, Oslo (Norway); Risnes, S. [Univ. of Oslo, Dept. of Oral Biology, Faculty of Dentistry, Oslo (Norway); Fischer, P.M. [Chalmers Univ. of Technology, Dept. of Physics, SIMS Lab., Goeteborg (Sweden)

1996-10-01

A blackish staining found on the crowns of teeth of 51 skulls from the excavation of the medieval St. Olav`s church in Trondheim was analyzed using secondary ion mass spectrometry (SIMS) and atomic absorption spectrometry (AAS). In four teeth, mass spectra and step scan concentration profiles of SIMS were performed and compared with the grey scale pattern in photographs of the analyzed paths. The manganese curve showed the highest degree of conformity with the grey scale pattern. The AAS analysis confirmed the increased content of manganese in blackish stained enamel. It was concluded that manganese, probably in the form of an oxide deposited from the soil, was the cause of the blackish staining. (au).

Trace element analysis of blackish staining on the crowns of human archaeological teeth

International Nuclear Information System (INIS)

Stermer, E.M.; Risnes, S.; Fischer, P.M.

1996-01-01

A blackish staining found on the crowns of teeth of 51 skulls from the excavation of the medieval St. Olav's church in Trondheim was analyzed using secondary ion mass spectrometry (SIMS) and atomic absorption spectrometry (AAS). In four teeth, mass spectra and step scan concentration profiles of SIMS were performed and compared with the grey scale pattern in photographs of the analyzed paths. The manganese curve showed the highest degree of conformity with the grey scale pattern. The AAS analysis confirmed the increased content of manganese in blackish stained enamel. It was concluded that manganese, probably in the form of an oxide deposited from the soil, was the cause of the blackish staining. (au)

Comparing the Effect of Different Voxel Resolutions for Assessment of Vertical Root Fracture of Permanent Teeth

International Nuclear Information System (INIS)

Uzun, Ismail; Gunduz, Kaan; Celenk, Peruze; Avsever, Hakan; Orhan, Kaan; Canitezer, Gozde; Ozmen, Bilal; Cicek, Ersan; Egrioglu, Erol

2015-01-01

The teeth with undiagnosed vertical root fractures (VRFs) are likely to receive endodontic treatment or retreatment, leading to frustration and inappropriate endodontic therapies. Moreover, many cases of VRFs cannot be diagnosed definitively until the extraction of tooth. This study aimed to assess the use of different voxel resolutions of two different cone beam computerized tomography (CBCT) units in the detection VRFs in vitro. The study material comprised 74 extracted human mandibular single rooted premolar teeth without root fractures that had not undergone any root-canal treatment. Images were obtained by two different CBCT units. Four image sets were obtained as follows: 1) 3D Accuitomo 170, 4 × 4 cm field of view (FOV) (0.080 mm 3 ); 2) 3D Accuitomo 170. 6 × 6 cm FOV (0.125 mm 3 ); 3) NewTom 3G, 6” (0.16 mm 3 ) and 4) NewTom 3G, 9” FOV (0.25 mm 3 ). Kappa coefficients were calculated to assess both intra- and inter-observer agreements for each image set. No significant differences were found among observers or voxel sizes, with high average Z (Az) results being reported for all groups. Both intra- and inter-observer agreement values were relatively better for 3D Accuitomo 170 images than the images from NewTom 3G. The highest Az and kappa values were obtained with 3D Accuitomo 170, 4 × 4 cm FOV (0.080 mm 3 ) images. No significant differences were found among observers or voxel sizes, with high Az results reported for all groups

Mesiodistal angulation of the lateral teeth to the functional occlusal plane in normal occlusions

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Hiroshi Ueda

2016-01-01

Full Text Available Introduction: Crowding is a malocclusion with irregularly positioned teeth caused by arch length discrepancy (ALD. Its incidence is high compared with the various malocclusions. In a previous study the crowns of the maxillary lateral teeth had erupted mesially in relation to the functional occlusal plane (FOP in patients with Angle Class I malocclusion and highly erupted canines, which had been uprighted by non-extraction orthodontic treatment, yet these results were based on only two cases evaluated by using plaster models. Therefore, the aim of this study was to assess the mesiodistal angulations of both maxillary and mandibular teeth relative to the FOP in normal occlusion by means of cephalograms and identifying the teeth axial factors contributing to the normal dentitions with the least ALD. Materials and Methods: Thirty Japanese young adult patients (6 males, 24 females with normal occlusion were selected to participate in this study; cephalograms were procured from each and the FOP was used as a reference plane for measuring the changes in the axial angulation along with other indicators of vertical growth. Results: Progressive mesial tipping of the maxillary lateral teeth was observed. First premolars tended to express this more than the second premolars but the tipping values were roughly 90° relative to the FOP on the first molars. Conclusion: The maxillary lateral teeth are more mesially angulated compared to the mandibular ones relative to the FOP. Furthermore, progressive mesial tipping of the maxillary lateral teeth was detected, of which axial angulations were significantly correlated to each other, in spite the mandibular premolars and molars being angulated in a similar fashion.

[Root resorption after orthodontic treatment: a study of age factor and prevalence in anterior teeth].

Science.gov (United States)

Tian, Yu-lou; Wang, Kun; Wang, Jing; Liu, Fang; Piao, Mei-ling

2013-04-01

To investigate the impact of age factor on root resorption and the prevalence in anterior teeth during orthodontic treatment. Sixty extraction cases treated with straight wire appliance were divided into adult group and child group, with 30 cases in each group.The panoramic radiographs pre-treatment and post-treatment were examined to measure the degrees of root resorption. A total of 360 anterior teeth in each group were evaluated. SPSS 13.0 software package was applied to perform statistical analysis. There was significant difference in root resorption index before and after treatment(Proot resorption increased remarkably after orthodontic treatment. There was significant difference in the degree of root resorption in two groups (Proot resorption in anterior teeth was: upper central incisors, upper lateral incisors, lower central incisors, lower lateral incisors, upper canines and lower canines. The root resorption in adult patients are more obvious than child patients. The prevalence of root resorption in anterior teeth is different. Moderate or severe root resorption is prone to happen in upper central incisors or lateral incisors in adult patients.

Antimicrobial efficacy of chlorine dioxide against Candida albicans in stationary and starvation phases in human root canal: An in-vitro study

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Shirur Krishnaraj Somayaji

2014-01-01

Full Text Available Introduction: Candida albicans (C. albicans is the most commonly isolated fungal pathogen from dental root canal. C. albicans forms biofilm and develops resistance against root canal irrigants . This study determines the fungicidal efficacy of 13.8% chlorine dioxide in extracted human teeth at stationary and starvation phases of C. albicans. Materials and Methods: Teeth were decoronated and coronal portion of the roots were prepared into blocks, which were incubated at 37°C with C. albicans for five days. The samples were treated with chlorine dioxide for 12 and 20 minutes. Total of fifty blocks were taken in the study. Colony-forming units were counted in Sabourauds dextrose agar and scanning electron microscopic observation was done. Data were analyzed by one-way ANOVA and Bonferoni′s post hoc test. Results: Teeth at stationary phase (12 min showed mean colony count of 28,000 ± 1814 which is significantly (P < 0.001 less than control group. Teeth at starvation phase (12 min showed colony count of 65,600 ± 1912 which is also significantly (P < 0.001 less than control group. Teeth irrigated at stationary phase (20 min showed mean colony count of 23,400 ± 1776 (P < 0.001. Teeth irrigated at starvation phase (20 min showed mean colony count of 48,100 ± 1663 which is also significantly (P < 0.001 less than that of control group. Conclusion: Treatment of chlorine dioxide reduces the C. albicans count in root canals of extracted human teeth at stationary and starvation phases. Efficacy of chlorine dioxide against C. albicans is relatively higher in stationary phase than that of starvation phase.

EPR dosimetry teeth in past and future accidents: A prospective look at a retrospective method

Energy Technology Data Exchange (ETDEWEB)

Haskell, E.; Kenner, G.; Hayes, R. [Univ. of Utah, Salt Lake City, UT (United States). Center for Applied Dosimetry; Chumak, V.; Shalom, S. [Scientific Center for Radiation Medicine, Kiev (Ukraine)

1997-03-01

Accurate assessments of doses received by individuals exposed to radiation from nuclear accidents and incidents such as those at Hiroshima and Nagasaki, the Nevada test site, Cheliabinsk and Mayak are required for epidemiological studies seeking to establish relationships between radiation dose and health effects. One method of retrospective dosimetry which allows for measurement of cumulative gamma ray doses received by exposed individuals is electron paramagnetic resonance spectroscopy (EPR) of tooth enamel. Tooth enamel stores and retains, indefinitely, information on absorbed radiation dose. And teeth are available in every population as a result of dental extraction for medical reasons including periodontal disease and impacted wisdom teeth. In the case of children, deciduous teeth, which are shed between the ages of 7 and 13, can be a very important dosimetric source if documented collection is implemented shortly following an accident.

EPR dosimetry teeth in past and future accidents: A prospective look at a retrospective method

International Nuclear Information System (INIS)

Haskell, E.; Kenner, G.; Hayes, R.

1997-01-01

Accurate assessments of doses received by individuals exposed to radiation from nuclear accidents and incidents such as those at Hiroshima and Nagasaki, the Nevada test site, Cheliabinsk and Mayak are required for epidemiological studies seeking to establish relationships between radiation dose and health effects. One method of retrospective dosimetry which allows for measurement of cumulative gamma ray doses received by exposed individuals is electron paramagnetic resonance spectroscopy (EPR) of tooth enamel. Tooth enamel stores and retains, indefinitely, information on absorbed radiation dose. And teeth are available in every population as a result of dental extraction for medical reasons including periodontal disease and impacted wisdom teeth. In the case of children, deciduous teeth, which are shed between the ages of 7 and 13, can be a very important dosimetric source if documented collection is implemented shortly following an accident

Classical music and the teeth.

Science.gov (United States)

Eramo, Stefano; Di Biase, Mary Jo; De Carolis, Carlo

2013-01-01

Teeth and their pathologies are frequent themes in classical music. The teeth have inspired popular songwriters such as Thomas Crecquillon, Carl Loewe, Amilcare Ponchielli & Christian Sinding; as well as composers whose works are still played all over the world, such as Robert Schumann and Jacques Offenbach. This paper examines several selections in which the inspiring theme is the teeth and the pain they can cause, from the suffering of toothache, to the happier occasion of a baby's first tooth.

Preformed crowns for decayed primary molar teeth.

Science.gov (United States)

Innes, Nicola P T; Ricketts, David; Chong, Lee Yee; Keightley, Alexander J; Lamont, Thomas; Santamaria, Ruth M

2015-12-31

21 January 2015). No restrictions were placed on the language or date of publication when searching the databases. Randomised controlled trials (RCTs) that assessed the effectiveness of crowns compared with fillings, other types of crowns, non-restorative approaches or no treatment in children with untreated tooth decay in one or more primary molar teeth. We would also have included trials comparing different methods of fitting crowns.For trials to be considered for this review, the success or failure of the interventions and other clinical outcomes had to be reported at least six months after intervention (with the exception of 'pain/discomfort during treatment and immediately postoperatively'). Two review authors independently assessed the title and abstracts for each article from the search results. and independently assessed the full text for each potentially relevant study. At least two authors assessed risk of bias and extracted data using a piloted data extraction form. We included five studies that evaluated three comparisons. Four studies compared crowns with fillings; two of them compared conventional PMCs with open sandwich restorations, and two compared PMCs fitted using the Hall Technique with fillings. One of these studies included a third arm, which allowed the comparison of PMCs (fitted using the Hall Technique) versus non-restorative caries treatment. In the two studies using crowns fitted using the conventional method, all teeth had undergone pulpotomy prior to the crown being placed. The final study compared two different types of crowns: PMCs versus aesthetic stainless steel crowns with white veneers. No RCT evidence was found that compared different methods of fitting preformed metal crowns (i.e. Hall Technique versus conventional technique).We considered outcomes reported at the dental appointment or within 24 hours of it, and in the short term (less than 12 months) or long term (12 months or more). Some of our outcomes of interest were not

The determination of 90Sr and 228Ra in human teeth by age groups and in other substances

International Nuclear Information System (INIS)

Neuzil, E.F.; Dysart, M.E.

1984-01-01

The total 90 Sr content of human teeth peaks at a value of 0.65 pCi/g calcium in the age group of 20-30 years. It is not present in those 50 years or older. Various other substances show extensive amounts of 90 Sr especially in cow bones, bone meal and dry milk. The radionuclide 228 Ra (daughter of 232 Th) is present at a mean level of about 0.5 pCi/g Ca in all substances tested and in all age groups, but especially high in bone meal (5.60 pCi/g Ca) and calcium lactate tablets. (author)

Treatment Outcomes of Full Pulpotomy as an Alternative to Tooth Extraction in Molars with Hyperplastic/Irreversible Pulpitis: A Case Report

Science.gov (United States)

Asgary, Saeed; Verma, Prashant; Nosrat, Ali

2017-01-01

Root canal therapy (RCT) is a common and successful treatment for irreversible pulpitis due to carious pulp exposure in mature permanent teeth. However, it is often an expensive procedure, may require multiple appointments, and requires a high level of training and clinical skill, specifically in molars. Uninsured patients, low-income patients, and patients with limited access to specialist care often elect for extraction of restorable teeth with irreversible pulpitis. There is a need for an alternative affordable treatment option to preserve their teeth and maintain chewing function. A case of pulpotomy using calcium-enriched mixture (CEM) cement in two maxillary molars (#14 and 15) in a healthy 36-year-old patient is presented. Both teeth were diagnosed with symptomatic hyperplastic/irreversible pulpitis. Patient did not have dental insurance, was unable to afford RCT, and refused to extract the teeth. CEM pulpotomy and amalgam build-ups were done as an alternative to extraction. At 2-year recall, both teeth were functional with no signs/symptoms of inflammation/infection. Periapical radiographs and 3D images showed normal PDL around all roots. Pulpotomy with CEM biomaterial might be a viable alternative to tooth extraction for mature permanent teeth with hyperplastic/irreversible pulpitis, and can result in long-term tooth retention and improved oral health. PMID:28512498

Identification of human remains from the Second World War mass graves uncovered in Bosnia and Herzegovina.

Science.gov (United States)

Marjanović, Damir; Hadžić Metjahić, Negra; Čakar, Jasmina; Džehverović, Mirela; Dogan, Serkan; Ferić, Elma; Džijan, Snježana; Škaro, Vedrana; Projić, Petar; Madžar, Tomislav; Rod, Eduard; Primorac, Dragan

2015-06-01

To present the results obtained in the identification of human remains from World War II found in two mass graves in Ljubuški, Bosnia and Herzegovina. Samples from 10 skeletal remains were collected. Teeth and femoral fragments were collected from 9 skeletons and only a femoral fragment from 1 skeleton. DNA was isolated from bone and teeth samples using an optimized phenol/chloroform DNA extraction procedure. All samples required a pre-extraction decalcification with EDTA and additional post-extraction DNA purification using filter columns. Additionally, DNA from 12 reference samples (buccal swabs from potential living relatives) was extracted using the Qiagen DNA extraction method. QuantifilerTM Human DNA Quantification Kit was used for DNA quantification. PowerPlex ESI kit was used to simultaneously amplify 15 autosomal short tandem repeat (STR) loci, and PowerPlex Y23 was used to amplify 23 Y chromosomal STR loci. Matching probabilities were estimated using a standard statistical approach. A total of 10 samples were processed, 9 teeth and 1 femoral fragment. Nine of 10 samples were profiled using autosomal STR loci, which resulted in useful DNA profiles for 9 skeletal remains. A comparison of established victims' profiles against a reference sample database yielded 6 positive identifications. DNA analysis may efficiently contribute to the identification of remains even seven decades after the end of the World War II. The significant percentage of positively identified remains (60%), even when the number of the examined possible living relatives was relatively small (only 12), proved the importance of cooperation with the members of the local community, who helped to identify the closest missing persons' relatives and collect referent samples from them.

Teeth re-whitening effect of strawberry juice on coffee stained teeth

OpenAIRE

Annisya Pramesti; Tadeus Arufan Jasrin; Opik Taofik Hidayat

2018-01-01

Many people favor coffee. However, regarding health and aesthetic dentistry, coffee gives a negative effect. Tanin in coffee causes a brown stain on the tooth surface. Therefore, in aesthetic dental care, teeth whitening has become popular matter. One of the natural ingredients used for teeth whitening treatment is strawberry. The purpose of this study was to obtained data regarding the effect of strawberry juice on the re-whitening process of the coffee-stained tooth enamel surface. This stu...

Isolation and evaluation of dental pulp stem cells from teeth with advanced periodontal disease.

Science.gov (United States)

Derakhshani, Ali; Raoof, Maryam; Dabiri, Shahriar; Farsinejad, Ali Reza; Gorjestani, Hedayat; Yaghoobi, Mohammad Mehdi; Shokouhinejad, Noushin; Ehsani, Maryam

2015-04-01

Successful isolation of mesenchymal stem cells from waste tissues might be extremely promising for developing stem cell-based therapies. This study aimed to explore whether cells retrieved from teeth extracted due to advanced periodontal disease present mesenchymal stem cell-like properties. Pulp cells were isolated from 15 intact molars and 15 teeth with advanced periodontal disease. Cell proliferation and markers of mesenchymal stem cells were evaluated. Based on the RT-PCR and agarose gel electrophoresis, nucleostemin, Oct-4 and jmj2c, but not Nanog, were expressed in undifferentiated mesenchymal stem cells of both groups. Interestingly, diseased pulp exhibited higher gene expressions although it was not statistically significant. The average percentage of BrdU positive cells in the diseased group (84.4%, n = 5) was significantly higher than that of the control group (65.4%, n = 5) (t-test, P = 0.001). Our results indicate the successful isolation of mesenchymal stem cells from the pulp tissue of hopeless periodontally involved teeth.

Evaluation of the reinforcement effect on teeth with different apical foramen diameters of retrograde or orthograde MTA application with internal matrix

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Emre Bayram

2016-01-01

Full Text Available OBJECTIVE: The aim of this study was to determine the effect of the apical foramen diameter and different application methods of Mineral Trioxide Aggregate (MTA on the fracture resistance of simulated immature teeth using a Universal Testing Machine. MATERIALS AND METHOD: Ninety extracted human teeth were used for the fracture resistance test. The apical foramen was prepared to a diameter of 1.0 mm or 1.4 mm to simulate the open apex of immature teeth. MTA was mixed according to manufacturer's recommendations and placed into the root canals with different apical foramen diameter by four different root filling techniques: retrograde, two-phased orthograde, and ortograde with or without internal matrix. Prepared roots were marked 2 mm below the cemento-enamel junction and embedded in transparent acrylic resin in cylinder moulds. Vertical force was applied along the long axis of the tooth at a speed of 5 mm/min, and the maximum resistance to fracture for each tooth was determined in Newton. A software package was used for the statistical analysis. The data were analyzed by using one-way ANOVA and post-hoc Tukey tests. RESULTS: A statistically significant difference could not be observed between the groups (p>0.05 whereas statistically significant differences were found between the test groups and the control groups (p<0.05. CONCLUSION: There was no significant difference between different vertical root filling techniques in increasing the fracture strength of the teeth. The diameter of the apical foramen did not have a significant effect on the fracture resistance.

Miniature Pulpotomy of Symptomatic Mature Permanent Teeth: A Report of Two Cases.

Science.gov (United States)

Asgary, Saeed; Nourzadeh, Mahdieh; Eghbal, Mohammad Jafar

2016-01-01

Human dental pulp inflammation can progress to periapical lesion formation and conventional root canal treatment (RCT) has been the traditional method for disease management. This observational study presents two cases of vital pulp therapy in mature molars diagnosed with irreversible pulpitis and associated with apical periodontitis. In these two clinical cases, the involved teeth had deep carious lesions with a history of spontaneous/lingering pain and radiographic examinations revealed the presence of apical radiolucencies. A conservative miniature pulpotomy (MP) using calcium-enriched mixture (CEM) was performed and the teeth were permanently restored with amalgam. Clinical evaluations indicated resolution of pain 24 hours after treatment; the teeth showed normal vitality, remained asymptomatic and maintained normal function after recall examinations. Furthermore, the 18-month radiographic evaluation showed healing of the apical lesions. Vital pulp therapy using the MP technique with CEM appeared successful in avoiding RCT intervention. These two reports of case outcome suggest that simple MP using a CEM bioregenerative technique may provide a favorable outcome for permanent teeth diagnosed with irreversible pulpitis and associated with apical periodontitis.

Facilitatory effect of AC-iontophoresis of lidocaine hydrochloride on the permeability of human enamel and dentine in extracted teeth.

Science.gov (United States)

Ikeda, Hideharu; Suda, Hideaki

2013-04-01

The objectives of the present study were to quantitatively evaluate chemical permeability through human enamel/dentine using conductometry and to clarify if alternating current (AC) iontophoresis facilitates such permeability. Electrical impedance of different concentrations of lidocaine hydrochloride was measured using a bipolar platinum impedance probe. A quadratic curve closely fitted to the response functions between conductance and lidocaine hydrochloride. For analysis of the passage of lidocaine hydrochloride through human enamel/dentine, eight premolars that were extracted for orthodontic treatment were sectioned at the cemento-enamel junction. The tooth crowns were held between two chambers with a double O-ring. The enamel-side chamber was filled with lidocaine hydrochloride, and the pulp-side chamber was filled with extrapure water. Two platinum plate electrodes were set at the end of each chamber to pass alternating current. A simulated interstitial pulp pressure was applied to the pulp-side chamber. The change in the concentration of lidocaine hydrochloride in the pulp-side chamber was measured every 2min using a platinum recording probe positioned at the centre of the pulp-side chamber. Passive entry without iontophoresis was used as a control. The level of lidocaine hydrochloride that passed through enamel/dentine against the dentinal fluid flow increased with time. Electrical conductance (G, mho) correlated closely to the concentration (x, mmol/L) of lidocaine hydrochloride (G=2.16x(2)+0.0289x+0.000376, r(2)=0.999). Lidocaine hydrochloride can pass through enamel/dentine. Conductometry showed that the level of lidocaine hydrochloride that passed through enamel/dentine was increased by AC iontophoresis. Copyright © 2012 Elsevier Ltd. All rights reserved.

Probing around implants and teeth with healthy or inflamed peri-implant mucosa/gingival. A histologic comparison in cynomolgus monkeys. (Macaca fascicularis)

DEFF Research Database (Denmark)

Schou, Søren; Holmstrup, Palle; Stoltze, K.

2002-01-01

Osseointegrated oral implants; teeth; phathology; peri-implant mucositis; gingivitis; peri-implantitis; periodontitis; diagnosis; probing depth; non-human primates; cynomolgus monkeys: Macaca fascicularis......Osseointegrated oral implants; teeth; phathology; peri-implant mucositis; gingivitis; peri-implantitis; periodontitis; diagnosis; probing depth; non-human primates; cynomolgus monkeys: Macaca fascicularis...

Human DNA Extraction by Two Extraction Methods for Forensic Typification from Human Feces on FTA Paper

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Shirleny Monserrat Sandoval-Arias

2014-11-01

Full Text Available The identification of suspects in criminal investigations has been facilitated since DNA test are executed on different samples. The application of this technology for forensic typification from human fecal samples still presents complications therefore this research evaluated two DNA extraction protocols with modifications to determine that of major efficiency. Organic extractions and extractions using the commercial kit “IQTM DNA Casework Sample Kit for Maxwell ® 16” on FTA portions of 4cm2 and 1cm2 impregnated with feces from the same individual were done to accomplish the objective. In all the assays the results were useful, however; the best forensic typification (by the electropherogram characteristics was obtained by using the commercial kit in an area of 1 cm2 of FTA paper impregnated in a 1:4 dilution.

Expression of DMP-1 in the human pulp tissue using low level laser therapy

International Nuclear Information System (INIS)

Neto, Natalino Lourenço; Teixeira Marques, Nádia Carolina; Fernandes, Ana Paula; Silva, Thiago Cruvinel; Andrade Moreira Machado, Maria Aparecida; Oliveira, Thais Marchini; Rodini, Camila Oliveira

2015-01-01

This study aimed to evaluate the effects of low-level laser therapy (LLLT) on DMP-1 expression in pulp tissue repair of human primary teeth. Twenty mandibular primary molars were randomly assigned into the following groups: Group I—Buckley’s Formocresol (FC); Group II—Calcium Hydroxide (CH); Group III—LLLT + CH and Group IV—LLLT + Zinc oxide/Eugenol. The teeth at the regular exfoliation period were extracted for histological analysis and immunolocalization of DMP-1. Descriptive analysis was performed on the dentin pulp complex. Histopathological assessment showed internal resorption in group FC. Groups CH and LLLT + CH provided better pulpal repair due to the absence of inflammation and the formation of hard tissue barrier. These two groups presented odontoblastic layer expressing DMP-1. According to this study, low level laser therapy preceding the use of calcium hydroxide exhibited satisfactory bio-inductive activity on pulp tissue repair of human primary teeth. However, other histological and cellular studies are needed to confirm the laser tissue action and efficacy. (paper)

Crack arrest within teeth at the dentinoenamel junction caused by elastic modulus mismatch

OpenAIRE

Bechtle, Sabine

2010-01-01

Enamel and dentin compose the crowns of human teeth. They are joined at the dentinoenamel junction (DEJ) which is a very strong and well-bonded interface unlikely to fail within healthy teeth despite the formation of multiple cracks within enamel during a lifetime of exposure to masticatory forces. These cracks commonly are arrested when reaching the DEJ. The phenomenon of crack arrest at the DEJ is described in many publications but there is little consensus on the underlying cause and mecha...

CBVT analysis of canal configuration of the mesio-buccal root of maxillary first permanent molar teeth: An in vitro study.

Science.gov (United States)

Shenoi, R Pratima; Ghule, Hrishikesh M

2012-07-01

For successful endodontic treatment, it's imperative to locate and obturate all root canals. As concluded by Ingle, the major cause for failure of root canal therapy is in ability to recognize all theexisting canals and subsequent failure in their obturation. To analyze the canal configuration of the mesio-buccal root of maxillary first permanent molar teeth. A total of 30 recently extracted human permanent maxillary first molars were collected and stored in a container with 5% Sodium Chloride solution for four days. Teeth with open apices, external resorption, improperly formed roots and teeth with previous restorations were excluded. Using the dental modeling wax, teeth were arranged in a 'U' shaped arch with roots embedded inside the wax and occlusal surface remaining free. 10 teeth were arranged in each arch and three such sample plates were prepared. Flat surface of the base encasing enabled the plate to be mounted on flat plastic bite plate. With bite plate roughly centered in the focal trough area Axial, Coronal and Sagittal section Cone-Beam Computed Tomography (CBCT) images were taken with Kodak 9000 Extra-oral Imaging System. Images displayed on a monitor were inspected by two endodontists using Kodak Dental Imaging Software 3D Module V2.2. When the data was observed, it was found that 24 teeth out of total 30 teeth examined showed some variation (i.e. possible additional canal) along the length of the mesio-buccal root canal. Out of these 24 teeth, 13 showed presence of additional canal at coronal third, 7 showed presence of additional canal at middle third and four showed presence of additional canal in apical third level. Percentage analysis was done as there was no group comparison to be done. Cone-Beam Volumetric Tomography (CBVT) evaluation positively identified the variations in mesio-buccal canal in 80% of samples. Out of these, 54.16% were in coronal 3(rd), 29.16% in middle 3(rd) and 16.66% were in apical 3(rd). Within the limitations of this

CBVT analysis of canal configuration of the mesio-buccal root of maxillary first permanent molar teeth: An in vitro study

Directory of Open Access Journals (Sweden)

R Pratima Shenoi

2012-01-01

Full Text Available Context: For successful endodontic treatment, it′s imperative to locate and obturate all root canals. As concluded by Ingle, the major cause for failure of root canal therapy is in ability to recognize all theexisting canals and subsequent failure in their obturation. Aim: To analyze the canal configuration of the mesio-buccal root of maxillary first permanent molar teeth. Materials and Methods: A total of 30 recently extracted human permanent maxillary first molars were collected and stored in a container with 5% Sodium Chloride solution for four days. Teeth with open apices, external resorption, improperly formed roots and teeth with previous restorations were excluded. Using the dental modeling wax, teeth were arranged in a ′U′ shaped arch with roots embedded inside the wax and occlusal surface remaining free. 10 teeth were arranged in each arch and three such sample plates were prepared. Flat surface of the base encasing enabled the plate to be mounted on flat plastic bite plate. With bite plate roughly centered in the focal trough area Axial, Coronal and Sagittal section Cone-Beam Computed Tomography (CBCT images were taken with Kodak 9000 Extra-oral Imaging System. Images displayed on a monitor were inspected by two endodontists using Kodak Dental Imaging Software 3D Module V2.2. Statistical Analysis: When the data was observed, it was found that 24 teeth out of total 30 teeth examined showed some variation (i.e. possible additional canal along the length of the mesio-buccal root canal. Out of these 24 teeth, 13 showed presence of additional canal at coronal third, 7 showed presence of additional canal at middle third and four showed presence of additional canal in apical third level. Percentage analysis was done as there was no group comparison to be done. Results: Cone-Beam Volumetric Tomography (CBVT evaluation positively identified the variations in mesio-buccal canal in 80% of samples. Out of these, 54.16% were in coronal 3 rd

Tensile Bond Strengths of Two Adhesives on Irradiated and Nonirradiated Human Dentin

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Cécile Bernard

2015-01-01

Full Text Available The aim of this study was to assess the effect of radiotherapy on bond efficiency of two different adhesive systems using tensile bond strength test. Twenty extracted teeth after radiotherapy and twenty nonirradiated extracted teeth were used. The irradiation was applied in vivo to a minimal dose of 50 Gy. The specimens of each group were randomly assigned to two subgroups to test two different adhesive systems. A three-step/etch-and-rinse adhesive system (Optibond FL and a two-steps/self-etch adhesive system (Optibond XTR were used. Composite buildups were performed with a nanohybrid composite (Herculite XTR. All specimens were submitted to thermocycling ageing (10000 cycles. The specimens were sectioned in 1 mm2 sticks. Microtensile bond strength tests were measured. Nonparametric statistical analyses were performed due to nonnormality of data. Optibond XTR on irradiated and nonirradiated teeth did not show any significant differences. However, Optibond FL bond strength was more effective on nonirradiated teeth than on irradiated teeth. Within the limitations of an in vitro study, it can be concluded that radiotherapy had a significant detrimental effect on bond strength to human dentin. However, it seems that adhesive choice could be adapted to the substrata. According to the present study, the two-steps/self-etch (Optibond XTR adhesive system tested could be more effective on irradiated dentin compared to three-steps/etch-and-rinse adhesive system (Optibond FL.

EPR dosimetry of teeth in past and future accidents. A prospective look at a retrospective method

Energy Technology Data Exchange (ETDEWEB)

Haskell, E.; Kenner, G.; Hayes, R. [Center for Applied Dosimetry, Salt Lake City, UT (United States); Chumak, V.; Shalom, S.

1996-12-31

Accurate assessments of doses received by individuals exposed to radiation from nuclear accidents and incidents such as those at Hiroshima and Nagasaki, the Nevada test site, Chelyabinsk and Mayak are required for epidemiological studies seeking to establish relationships between radiation dose and health effects. One method of retrospective dosimetry which allows for measurement of cumulative gamma ray doses received by exposed individuals is electron paramagnetic resonance spectroscopy (EPR) of tooth enamel. Tooth enamel stores and retains, indefinitely, information on absorbed radiation dose; and teeth are available in every population as a result of dental extraction for medical reasons including periodontal disease and impacted wisdom teeth. In the case of children, deciduous teeth, which are shed between the ages of 7 and 13, can be a very important dosimetric source if documented collection is implemented shortly following an accident. (author)

Pulp tissue from primary teeth: new source of stem cells

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Paloma Dias Telles

2011-06-01

Full Text Available SHED (stem cells from human exfoliated deciduous teeth represent a population of postnatal stem cells capable of extensive proliferation and multipotential differentiation. Primary teeth may be an ideal source of postnatal stem cells to regenerate tooth structures and bone, and possibly to treat neural tissue injury or degenerative diseases. SHED are highly proliferative cells derived from an accessible tissue source, and therefore hold potential for providing enough cells for clinical applications. In this review, we describe the current knowledge about dental pulp stem cells and discuss tissue engineering approaches that use SHED to replace irreversibly inflamed or necrotic pulps with a healthy and functionally competent tissue that is capable of forming new dentin.

90Sr specific activity of teeth of abandoned cattle after the Fukushima accident - teeth as an indicator of environmental pollution.

Science.gov (United States)

Koarai, Kazuma; Kino, Yasushi; Takahashi, Atsushi; Suzuki, Toshihiko; Shimizu, Yoshinaka; Chiba, Mirei; Osaka, Ken; Sasaki, Keiichi; Urushihara, Yusuke; Fukuda, Tomokazu; Isogai, Emiko; Yamashiro, Hideaki; Oka, Toshitaka; Sekine, Tsutomu; Fukumoto, Manabu; Shinoda, Hisashi

2018-03-01

90 Sr specific activity in the teeth of young cattle that were abandoned in Kawauchi village and Okuma town located in the former evacuation areas of the Fukushima-Daiichi Nuclear Power Plant (FNPP) accident were measured. Additionally, specific activity in contaminated surface soils sampled from the same area was measured. (1) All cattle teeth examined were contaminated with 90 Sr. The specific activity, however, varied depending on the developmental stage of the teeth during the FNPP accident; teeth that had started development before the accident exhibited comparatively lower values, while teeth developed mainly after the accident showed higher values. (2) Values of 90 Sr-specific activity in teeth formed after the FNPP accident were higher than those of the bulk soil but similar to those in the exchangeable fraction (water and CH 3 COONH 4 soluble fractions) of the soil. The findings suggest that 90 Sr was incorporated into the teeth during the process of development, and that 90 Sr in the soluble and/or leachable fractions of the soil might migrate into teeth and contribute to the amount of 90 Sr in the teeth. Thus, the concentration of 90 Sr in teeth formed after the FNPP accident might reflect the extent of 90 Sr pollution in the environment. Copyright © 2017 Elsevier Ltd. All rights reserved.

Extraction protocols for orthodontic treatment: A retrospective study

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Vaishnevi N Thirunavukkarasu

2016-01-01

Full Text Available Background and Objectives: Various extraction protocols have been followed for successful orthodontic treatment. The purpose of this study was to evaluate the extraction protocols in patients who had previously undergone orthodontic treatment and also who had reported for continuing orthodontic treatment from other clinics. Materials and Methods: One hundred thirty eight patients who registered for orthodontic treatment at the Faculty of Dentistry were divided into 10 extraction protocols based on the Orthodontic treatment protocol given by Janson et al. and were evaluated for statistical significance. Results: The descriptive statistics of the study revealed a total of 40 (29% patients in protocol 1, 43 (31.2% in protocol 2, 18 (13% in protocol 3, 16 (11.6% in protocol 5, and 12 (8.7% in Type 3 category of protocol 9. The Type 3 category in protocol 9 was statistically significant compared to other studies. Midline shift and collapse of the arch form were noticed in these individuals. Conclusion: Extraction of permanent teeth such as canine and lateral incisors without rational reasons could have devastating consequences on the entire occlusion. The percentage of cases wherein extraction of permanent teeth in the crowded region was adopted as a treatment option instead of orthodontic treatment is still prevalent in dental practice. The shortage of orthodontists in Malaysia, the long waiting period, and lack of subjective need for orthodontic treatment at an earlier age group were the reasons for the patient's to choose extraction of the mal-aligned teeth such as the maxillary canine or maxillary lateral incisors.

Sustainable extraction of molecules for human food, cosmetic and pharmaceutical products: extraction in supercritical fluids

International Nuclear Information System (INIS)

Leone, GianPaolo; Ferri, Donatella

2015-01-01

Since several years, the ENEA Innovation Laboratory for Agro-Industrial, proposed activities of research and development of extraction processes with supercritical fluids (SFE, Supercritical Fluid Extraction), focusing on sustainability characteristics of the process. The technique, in fact, makes no use of organic solvents, has a low energy consumption and requires a lower number of process steps compared to conventional extractions. The process also responds to the requirements imposed by the legislation for human food, cosmetic and pharmaceutical extracts. [it

Mothers Perception of Teething in Children

African Journals Online (AJOL)

TNHJOURNALPH

includes blistering, bleeding, placing leeches on the gum, applying cautery to the back of the head and lancing- a method where lancet was used to cut the gum in other for the teeth to appear.7 1t was thought that failure of the teeth to appear was due to lack of a pathway and that this was the cause of death from teething,.

The human periodontal membrane: focusing on the spatial interrelation between the epithelial layer of Malassez, fibers, and innervation

DEFF Research Database (Denmark)

Kjaer, Inger; Nolting, Dorrit

2009-01-01

OBJECTIVE: The purpose of the present study was to map the spatial interrelation of fibers, peripheral nerves, and epithelial layer of Malassez in human periodontal membrane in areas close to the root surfaces. MATERIAL AND METHODS: Four healthy permanent teeth extracted from four patients during...

Comparative study of the fluorescence intensity of dental composites and human teeth submitted to artificial aging.

Science.gov (United States)

Jablonski, Tatiana; Takahashi, Marcos Kenzo; Brum, Rafeal Torres; Rached, Rodrigo Nunes; Souza, Evelise M

2014-01-01

The aim of this study was to evaluate quantitatively the fluorescence of resin composites and human teeth, and to determine the stability of fluorescence after aging. Ten specimens were built using a 1 mm thick increment of dentin composite overlapped by a 0.5 mm thick increment of enamel composite. Ten sound human molars were sectioned and silicon carbide-polished to obtain enamel and dentin slabs 1.5 mm in thickness. Fluorescence measurements were carried out by a fluorescence spectrophotometer before and after thermocycling (2000 cycles, 5°C and 55°C). One-way analysis of variance (ANOVA) with repeated measures and Tukey's test were performed at a significance level of 5%. Most of the tested composites showed significant differences in fluorescence both before and after aging (P 0.05), and was the only composite that showed comparable results of fluorescence to the tooth structure before and after thermocycling. With the exception of Filtek Supreme, there were significant reductions in fluorescence intensity for all the tested composites (P < 0.05).

Pulpal blood flow recorded from human premolar teeth with a laser Doppler flow meter using either red or infrared light.

Science.gov (United States)

Kijsamanmith, Kanittha; Timpawat, Siriporn; Vongsavan, Noppakun; Matthews, Bruce

2011-07-01

To compare red (635 nm) and infrared (780 nm) light for recording pulpal blood flow from human premolar teeth. Recordings were made from 11 healthy teeth in 9 subjects (aged 16-30 years) using a laser Doppler flow meter (Periflux 4001) equipped with both red and infrared lasers. Average blood flow signals were obtained with both light sources alternately from each tooth under five conditions: intact tooth without opaque rubber dam, intact tooth with dam, after injecting local anaesthetic (3% Mepivacaine) (LA) over the apex of the tooth and cavity preparation to almost expose the pulp, after removal and replacement of the pulp, and with the root canal empty. With infrared light, the dam significantly decreased the mean blood flow by 80%. Injecting LA and cavity preparation had no significant effect. Removal and replacement of the pulp reduced the mean blood flow by 58%. There was no further change when the pulp was removed. With red light, the dam reduced the signal from intact teeth by 60%. Injecting LA and cavity preparation had no significant effect. The signal fell by 67% after pulp removal and replacement and did not change significantly when the pulp was removed. Opaque rubber dam minimises the contribution of non-pulpal tissues to the laser Doppler signal recorded from premolars. Using dam, the pulp contributed about 60% to the blood flow signal with both red and infrared light. The difference between them in this respect was not significant. Copyright © 2010 Elsevier Ltd. All rights reserved.

Periodontal Reasons for Tooth Extraction in a Group of Greek Army Personnel

OpenAIRE

Chrysanthakopoulos, Nikolaos Andreas

2011-01-01

Background and aims. The aim of this study was to investigate the prevalence of permanent teeth extracted due to periodontal disease and its relation to age, military rank, and type of extracted teeth due to periodontal and non-periodontal reasons among a group of Greek Army personnel attending a military dental practice. Materials and methods. Study population consisted of 509 officers, non-commissioned officers and soldiers, aged 18 to 44 years from a military dental hospital in...

Assessment of endodontically treated teeth by using different radiographic methods: an ex vivo comparison between CBCT and other radiographic techniques

Energy Technology Data Exchange (ETDEWEB)

Demiralp, Kemal Oeaguer; Uecok, Oezlem [Dept. of Dentomaxillofacial Radiology, Faculty of Dentistry, Gazi University, Ankara (Turkmenistan); Kamburoglu, Kivanc [Dept. of Dentomaxillofacial Radiology, Faculty of Dentistry, Ankara University, Ankara (Turkmenistan); Selcen Yuesel, Kahraman Guengoer [Dept. of Biostatistics, Faculty of Medicine, Ankara University, Ankara (Turkmenistan); Demiralp, Gokcen [Dept. of Endodontics, Tepebasi Dental Health Center, Ankara (Turkmenistan)

2012-09-15

To compare different radiographic methods for assessing endodontically treated teeth. Root canal treatments were applied in 120 extracted mandibular teeth, which were divided into four groups: (1) ideal root canal treatment (60 teeth), (2) insufficient lateral condensation (20 teeth), (3) root canals filled short of the apex (20 teeth), (4) overfilled root canal treatment (20 teeth). The teeth were imaged using intraoral film, panoramic film, digital intraoral systems (CCD and PSP), CCD obtained with portable X-ray source, digital panoramic, and CBCT images obtained at 0.3 mm{sup 3} and 0.2 mm'3 voxel size. Images were evaluated separately by three observers, twice. Kappa coefficients were calculated. The percentage of correct readings obtained from each modality was calculated and compared using a t-test (p<0.05). The intra-observer kappa for each observer ranged between 0.327 and 0.849. The inter-observer kappa for each observer for both readings ranged between 0.312 and 0.749. For the ideal root canal treatment group, CBCT with 0.2 mm{sup 3} voxel images revealed the best results. For insufficient lateral condensation, the best readings were found with periapical film followed by CCD and PSP. The assessment of teeth with root canals filled short of the apex showed the highest percentage of correct readings by CBCT and CCD. For the overfilled canal treatment group, PSP images and conventional periapical film radiographs had the best scores. CBCT was found to be successful in the assessment of teeth with ideal root canal treatment and teeth with canals filled short of the apex.

Detection of stain formation on teeth by oral antiseptic solution using fiber optic displacement sensor

Science.gov (United States)

Rahman, H. A.; Rahim, H. R. A.; Harun, S. W.; Yasin, M.; Apsari, R.; Ahmad, H.; Wan Abas, W. A. B.

2013-02-01

The application of a simple intensity modulated fiber optic displacement sensor for the detection of stain formation on human teeth is demonstrated. The proposed sensor uses a concentric type bundled plastic optical fiber (POF) as a probe in conjunction with the surfaces of five human teeth as the reflecting targets. Prior to the experiment, the stains were produced extrinsically by soaking the teeth in different concentrations of oral antiseptic solution containing hexetidine. The concentration of the oral antiseptic solution is measured in volume%. For a concentration change from 0% to 80%, the peak voltage decreases exponentially from 1.15 mV to 0.41 mV with a measured resolution of 0.48% and 1.75% for concentration ranges of 0-40% and 40-80%, respectively. The correlation between the detector output and variation in the color of human tooth surface has successfully been examined. Simple in design and low in cost, this sensor can detect color changes due to hexetidine-induced stain on a tooth surface in a fast and convenient way. Thus, this sensor will be very promising in esthetic dentistry, dental color matching techniques, chemical and biomedical applications.

Concrescent triplets involving primary anterior teeth

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Urvashi Sharma

2013-01-01

Full Text Available Odontogenesis is a complex process wherein more than 200 genes are known to play a significant role in tooth development. An imbalance can lead to an abnormality in the number, size, shape or structure of the developing tooth/teeth. The presence of an extra dental lamina forms a supernumerary tooth. The supernumerary teeth are of two types: A rudimentary tooth where the supernumerary tooth does not resemble any tooth in the normal series or a supplemental tooth in which this anomalous tooth resembles one in the normal series. It is also very rare to encounter triple teeth in primary dentition. The union of these teeth may be through fusion, gemination, concrescence or a combination of fusion and gemination. Presented is a rare case of concrescence involving maxillary deciduous incisors and a supplemental tooth in a 7-year-old boy. The differential diagnosis, etiology, and complications of primary anterior triple teeth are discussed.

Mouth and Teeth (For Parents)

Science.gov (United States)

... the teeth are subject to disease. A common periodontal disease is gingivitis — inflammation of the gums characterized by redness, swelling, and sometimes bleeding. The accumulation of tartar (a hardened film of food particles and bacteria that builds up on teeth) usually causes this ...

Effect of amalgam cuspal coverage on the fracture resistance of endodontically treated teeth

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Mahshid Mohammdi Basir

2013-05-01

Full Text Available   Background and Aims: Endodontically treated teeth are prone to fracture because they loose a big amount of their structure. The treatment plan of those teeth is completed when they are rehabilitated with a strong and functional restoration. The purpose of this study was to evaluate the fracture resistance of endodontically treated teeth restored with amalgam cuspal coverage in comparison with other restorative techniques.   Materials and Methods: 40 human healthy maxillary premolars were divided into 4 groups: group1 (S: sound teeth, group 2(Co: endodontically treated teeth with MOD cavity restored with bonding and composite, group 3(Am-B: endodontically treated teeth with MOD cavity restored with bonding and amalgam and group 4 (Am-CC: endodontically treated teeth with MOD cavity restored with amalgam cuspal coverage. Then the restorations were stored in water and room temperature for 100 days at then thermocycled for 500 cycles between water baths at (5.5 ± 1 and (55 ± 1 0 C. The fracture resistance was evaluated by universal testing machine (Instron, 1195 UK with the compressive force of about 2000 N in 0.5 mm/min. The fracture modes were evaluated in four groups by a stereomicroscope. Statistical analysis (Scheffe test was done for all groups (P0.05. The lowest fracture resistance was found in group 2 (Co (384 ± 137.4 N that had no significant difference with group 3 (Am-B (P>0.05. The fracture resistance in group 4 was significantly higher than group 2 (Co and 3 (Am-B. The fracture mode in group 1 was cohesive within tooth and in group 2 (Co and 3 (Am-B was mixed cohesive and adhesive, and in group 4 was cohesive within in restorative material.   Conclusion: The highest fracture resistance was found in teeth that received amalgam cuspal coverage.

Fracture resistance of endodontically treated permanent anterior teeth restored with three different esthetic post systems: An in vitro study

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Ameet J Kurthukoti

2015-01-01

Full Text Available Background: Esthetic coronal reconstruction of fractured anterior teeth is often performed using intra radicular posts. Most of the commonly used commercially esthetic post systems do not exhibit similar physical properties as dentin resulting in failures. Aim: To evaluate and compare the fracture resistance and mode of failure of simulated traumatized permanent central incisors restored with three different post systems including biologic dentin posts. Materials and Methods: A total of 40 recently extracted human maxillary central incisors with similar dimensions were decoronated 2 mm above the cemento-enamel junction and endodontically treated. Ten specimens were randomly selected as the Group I - Control group (core built teeth without intraradicular posts. The remaining 30 teeth were equally divided and restored with zirconia (Group II, n = 10, fiber re-inforced composite (FRC (Group III, n = 10 and biologic dentin posts (Group IV, n = 10 using resin bonded cement and their cores built-up. These samples were embedded in acrylic resin and then secured in a Universal Testing Machine and subjected to fracture resistance testing. The location of failure in the specimens was evaluated using a stereomicroscope. Results: Intergroup comparison revealed that the control group and zirconia post group (522 ± 110 N demonstrated the least fracture resistance, while dentin post group (721 ± 127 N the highest. There was no statistically significant difference between fiber post and dentin post groups. Fractures that were repairable were observed in fiber post and dentin post groups, whereas mostly unrestorable, catastrophic fractures were observed in the zirconia post group. Conclusion: Teeth restored with the biologic dentin post system demonstrated the highest fracture resistance and repairable fractures, closely followed by FRC post system. The least fracture resistance and most catastrophic fractures were demonstrated by the zirconia post system.

Anti-dentine Salivary SIgA in young adults with a history of dental trauma in deciduous teeth

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Gabriela Fleury SEIXAS

2015-01-01

Full Text Available Anti-dentin autoantibodies are associated with inflammatory root resorption in permanent teeth and are modulated by dental trauma and orthodontic force. However, it is not known whether deciduous tooth trauma can stimulate the development of a humoral immune response against dentin. The aim of this study was to evaluate the levels of salivary SIgA reactivity against human dentin extract in young adults with a history of trauma in the primary dentition. A sample of 78 patients, aged 18 to 25, who had completed an early childhood (0 to 5 years old caries prevention program years earlier at the Universidade Estadual de LondrinaPediatric Clinic, underwent radiographic examination and salivary sampling. Anti-dentin SIgA levels were analyzed by immunoenzymatic assay and Western blotting. Although dental trauma to deciduous teeth had occurred in 34 (43.6% of the patients, no differences in SIgA levels were detected between individuals who had experienced trauma and those who had not (p > 0.05. Multivariate regression analysis showed no association between dental trauma and SIgA levels (p > 0.05. Patients with a history of deciduous trauma presented low levels of anti-dentin antibodies, associated with orthodontic root resorption (p

ELECTRIC PULP TEST OF TEETH WITH PERIODONTAL DISEASE.

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Tsonko Uzunov

2014-10-01

Full Text Available Purpose: The aim of the research is to investigate the change in pulp vitality of teeth with periodontal disease using electric pulp tester (EPT. Methods: Subjected to observation were 108 patients with chronic periodontitis. Vitality of 805 teeth with periodontal pocket depth greater than 4 mm was studied by EPT. The research was conducted with EPT "Yonovit ". Results: The highest percentage of surveyed teeth (68.4% respond to the norm when they are tested with EPT – values between 3 μA and 10 μA . Teeth that respond to EPT with values ​​below 3 μA and between 35-100 μA are relatively equal - respectively 4.3% and 3.3%. With increased threshold of irritation – 10-35 μA react 23.4% of teeth. Small number of teeth have threshold of irritation over 100 μA - 0.6%. Conclusion: The value of EPT among periodontal damaged teeth depends on many factors - patient's age, extent of periodontal affect, group affiliation of teeth, etc.

Clinical Characteristics of Abutment Teeth with Gingival Discoloration.

Science.gov (United States)

Ristic, Ljubisa; Dakovic, Dragana; Postic, Srdjan; Lazic, Zoran; Bacevic, Miljana; Vucevic, Dragana

2017-04-06

The grey-bluish discoloration of gingiva (known as "amalgam tattoo") does not appear only in the presence of amalgam restorations. It may also be seen in cases of teeth restored with cast dowels and porcelain-fused-to-metal (PFM) restorations. The aim of this article was to determine the clinical characteristics of abutment teeth with gingival discoloration. This research was conducted on 25 patients referred for cast dowel and PFM restorations. These restorations were manufactured from Ni-Cr alloys. Ninety days after cementing the fixed prosthodontic restorations, the abutment teeth (n = 61) were divided into a group with gingival discoloration (GD) (n = 25) and without gingival discoloration (NGD) (n = 36). The control group (CG) comprised the contralateral teeth (n = 61). Plaque index, gingival index, clinical attachment level, and probing depth were assessed before fabrication and also 90 days after cementation of the PFM restorations. The gingival index, clinical attachment level, and probing depths of the abutment teeth that had GD were statistically higher before restoration, in comparison with the abutment teeth in the NGD and control groups. Ninety days after cementation, the abutment teeth with GD had significantly lower gingival indexes and probing depths, compared to the abutment teeth in the NGD group. Both abutment teeth groups (GD and NGD) had significantly higher values of clinical attachment levels when compared to the control group. There were no statistically significant differences in plaque index values between the study groups. The results of this study indicated that impairment of periodontal status of abutment teeth seemed to be related to the presence of gingival discolorations. Therefore, fabrication of fixed prosthodontic restorations requires careful planning and abutment teeth preparation to minimize the occurrence of gingival discolorations. With careful preparation of abutment teeth for cast dowels and crown restorations it may be

Inactivation of IL11 signaling causes craniosynostosis, delayed tooth eruption, and supernumerary teeth

DEFF Research Database (Denmark)

Nieminen, Pekka; Morgan, Neil V; Fenwick, Aimée L

2011-01-01

Craniosynostosis and supernumerary teeth most often occur as isolated developmental anomalies, but they are also separately manifested in several malformation syndromes. Here, we describe a human syndrome featuring craniosynostosis, maxillary hypoplasia, delayed tooth eruption, and supernumerary...... teeth. We performed homozygosity mapping in three unrelated consanguineous Pakistani families and localized the syndrome to a region in chromosome 9. Mutational analysis of candidate genes in the region revealed that all affected children harbored homozygous missense mutations (c.662C>G [p.Pro221Arg], c...... for the treatment of craniosynostosis....

Predictable management of cracked teeth with reversible pulpitis.

Science.gov (United States)

Abbott, P; Leow, N

2009-12-01

The aims of this study were to assess symptoms and signs caused by cracks in teeth and to assess a conservative management protocol. The symptoms and signs of 100 consecutive teeth that had reversible pulpitis associated with cracks were compared to findings from other reports. Teeth were managed with a conservative protocol which involved removal of cracks, caries and restorations, followed by placement of a sedative lining and interim restoration unless there were pulp exposures or insufficient tooth structure remaining. Teeth were monitored for pulp healing after three months and for up to five years. Eighty teeth did not require endodontic treatment. One tooth had an uncertain pulp status at review appointments. Fifteen teeth required endodontic treatment at the initial appointment because of carious pulp exposures (4 teeth), cracks extending into the pulp (2), and posts required (9). Four other teeth required endodontic treatment later following conservative pulp treatment due to continued pulpitis under the temporary restoration (1), pulpitis after core restoration (2), and pulp necrosis diagnosed at the review (1). Provided there is an accurate diagnosis of the pulp status and its cause, teeth with reversible pulpitis due to cracks can be treated conservatively without endodontic treatment in about 80 per cent of cases.

Long-term prognosis of endodontically treated teeth: a retrospective analysis of preoperative factors in molars.

Science.gov (United States)

Setzer, Frank C; Boyer, Keith R; Jeppson, Joshua R; Karabucak, Bekir; Kim, Syngcuk

2011-01-01

Long-term predictability of restored endodontically treated teeth is important for the decision of tooth retention versus extraction and implant placement. The purpose of this study was to validate the hypothesis that preoperative factors can predict the long-term prognosis of molars requiring endodontic and restorative treatment for future prognostic investigations. A clinical database was searched for molar endodontic treatments with crown placement and a minimum of 4-year follow-up. Charts of 42 patients with 50 individual treatments were randomly selected. Information concerning crown lengthening; periodontal diagnosis; attachment loss; furcation involvement; mobility; and internal, external, or periradicular resorption was recorded. Radiographs from treatment initiation and follow-up were digitalized. The presence of apical periodontitis was evaluated. Available ferrule was calculated from bitewing radiographs using CAD software (AutoCAD; Autodesk, Cupertino, CA). The resulting data, age, sex, and times of restoration and follow-up were analyzed for correlation with the presence of apical radiolucency at follow-up and the following four possible outcome scenarios: "no event," "nonsurgical retreatment," "surgical retreatment," or "extraction" using Spearman rank order correlation analysis. Patients' ages ranged from 19 to 87 years, 22 were male and 20 female, and 48 teeth (96.0%) were retained at follow-up. Of those, 44 (88.0%) were without intervention ("no event"), and four (8.0%) underwent surgical or nonsurgical retreatment. Two teeth (4.0%) had been extracted. Significant positive correlations existed between "untoward events" (any form of retreatment or extraction) and "prognostic value according to periodontal status" (p = 0.047) and "attachment loss" (p = 0.042). The only preoperative factors significant for the prognosis of restored endodontically treated molars were related to periodontal prognostic value and attachment loss. It can be concluded that

Delayed replantation of rat teeth after use of reconstituted powdered milk as a storage medium.

Science.gov (United States)

dos Santos, Cláudia Letícia Vendrame; Sonoda, Celso Koogi; Poi, Wilson Roberto; Panzarini, Sônia Regina; Sundefeld, Maria Lúcia Marçal Mazza; Negri, Márcia Regina

2009-02-01

Minimal extraoral dry storage period and moist storage for the avulsed tooth are identified as key steps for the treatment protocol of tooth replantation. Among the possible moist storage media, bovine milk has stood out because of its capacity of preserving the integrity of the periodontal ligament (PDL) fibers. This condition has attracted the attention to investigate the use of powdered milk, which is one of the presentation forms of bovine milk, as a feasible storage medium in cases of delayed tooth replantation. The aim of this study was to evaluate the healing process after delayed replantation of rat teeth stored in reconstituted powdered milk and long shelf-life (ultra high temperature) whole milk. Forty maxillary right rat incisors were assigned to four groups (n = 10): group I--the teeth were extracted and immediately replanted into theirs sockets; group II--the teeth were stored for 60 min in 200 ml of freshly reconstituted powdered milk; group III--the teeth were stored for 60 min in 200 ml of long shelf-life whole milk; group IV--the teeth were kept dry for the same time. All procedures were performed at room temperature. Next, the root canals of teeth in groups II, III, and IV were instrumented, filled with a calcium hydroxide-based paste, and replanted into their sockets. All animals received systemic antibiotic therapy and were killed by anesthetic overdose 60 days after replantation. The pieces containing the replanted teeth were removed, fixed, decalcified, and paraffin-embedded. Semi-serial 6-microm-thick sections were obtained and stained with hematoxylin and eosin for histomorphological analysis. There was statistically significant difference (P < 0.05) between groups I and IV regarding the presence of replacement resorption and PDL remnants on root surface. The powdered milk and long shelf-life whole milk presented similar results to each other and may be indicated as storage media for avulsed teeth.

Energy absorption build-up factors in teeth

International Nuclear Information System (INIS)

Manjunatha, H.C.; Rudraswamy, B.

2012-01-01

Geometric progression fitting method has been used to compute energy absorption build-up factor of teeth [enamel outer surface, enamel middle, enamel dentin junction towards enamel, enamel dentin junction towards dentin, dentin middle and dentin inner surface] for wide energy range (0.015-15 MeV) up to the penetration depth of 40 mean free path. The dependence of energy absorption build-up factor on incident photon energy, penetration depth, electron density and effective atomic number has also been studied. The energy absorption build-up factors increases with the penetration depth and electron density of teeth. So that the degree of violation of Lambert-Beer (I = I 0 e -μt ) law is less for least penetration depth and electron density. The energy absorption build-up factors for different regions of teeth are not same hence the energy absorbed by the different regions of teeth is not uniform which depends on the composition of the medium. The relative dose of gamma in different regions of teeth is also estimated. Dosimetric implication of energy absorption build-up factor in teeth has also been discussed. The estimated absorption build up factors in different regions of teeth may be useful in the electron spin resonance dosimetry. (author)

[Applicational evaluation of split tooth extractions of upper molars using piezosurgery].

Science.gov (United States)

Li, D; Guo, C B; Liu, Y; Wang, E B

2016-08-18

To evaluate the efficacy of Piezosurgery in split teeth extractions. A single-center, randomized, split-mouth study was performed using a consecutive serious of unrelated healthy patients attending the departing of oral and maxillofacial surgery, Peking University School and Hospital of Stomatology. 40 patients were selected for extraction of maxillary molars without reservation value,splitting or nonvital teeth. They were divided into control (20 patients) and test groups (20 patients) randomly. Surgical treatments for both groups were under local anesthesia. Molar teeth of control group were extracted by common equipments like dental elevators, chisels, forceps, etc. While molar teeth of experimental group were extracted by Piezosurgery, aided with the use of common equipments if needed. Then we compared the duration of surgery, frequency of the usage of chisels, expansion of postoperative bony socket surgical discomfort and postoperative pain between two groups. The average of operation time was (629.5±171.0) s in control group and (456.0±337.2) s in test group. The buccal alveolar bone reduced (1.07±0.64) mm in control group and (1.49±0.61) mm in test group. There was a significant difference between the two groups (P0.05). Piezosugery can be better to preserve alveolar bone, reduce trauma and patient's fear. Application of the piezosugery reflect the characteristics of minimally invasive extraction, which has the value of promotion. The Piezosurgery technique have the advantage of reducing change of buccal alveolar bone during the surgery, but a longer surgical time was required when compared with the conventional technique. VAS value of surgical discomfort, expansion of postoperative bony socket and the operative fear rate, there were no significant difference. Minimally invasive tooth extraction technique has good clinical results and high satisfaction. Piezosurgery proved its worth as the instrument adapted to limiting the destruction of bone tissue.

Comparison of lead levels in human permanent teeth from Strasbourg, Mexico City, and rural zones of Alsace

International Nuclear Information System (INIS)

Frank, R.M.; Sargentini-Maier, M.L.; Turlot, J.C.; Leroy, M.J.

1990-01-01

A comparative study of the mean lead concentrations in enamel and dentin of human premolars and permanent molars was conducted by means of a systematic sampling procedure with energy-dispersive x-ray fluorescence analysis. In a first series of analyses, no significant statistical differences in mean lead concentrations at various levels of enamel and dentin were noted between young patients of Strasbourg and those of small villages of Alsace, nor between elderly patients living in these two locations, despite the fact that motor traffic was significantly lower in the rural zones. However, in both locations, a significantly higher concentration of lead was observed in enamel and dentin in relation to age. In a second series of analyses, the mean lead concentrations of both dental hard tissues of premolars and permanent molars of young individuals from Strasbourg, rural Alsace, and Mexico City were compared. Significantly higher mean lead concentrations were found in enamel and dentin samples from Mexico City. This was most evident for inner coronal dentin (5.7 and 6.1 times greater than in teeth of Strasbourg and rural zones of Alsace, respectively) and for pulpal root dentin (6.9 and 8.9 times greater than in teeth of Strasbourg and rural zones of Alsace). It is proposed that the higher lead concentrations are related to the higher lead content of motor gasoline and to more intense traffic conditions. The dental hard tissues appear to be of value for the study of environmental lead pollution

A Systematic Review of Human Bat Rabies Virus Variant Cases: Evaluating Unprotected Physical Contact with Claws and Teeth in Support of Accurate Risk Assessments.

Science.gov (United States)

Dato, Virginia M; Campagnolo, Enzo R; Long, Jonah; Rupprecht, Charles E

2016-01-01

In the United States and Canada, the most recent documented cases of rabies have been attributed to bat rabies viruses (RABV). We undertook this systematic review in an effort to summarize and enhance understanding of the risk of infection for individuals who have been potentially exposed to a suspect or confirmed rabid bat. United States rabies surveillance summaries documented a total of 41 human bat-rabies virus variant verified non-transplant cases between 1990 and 2015. All cases were fatal. Seven (17.1%) of 41 cases reported a bite from a bat. Ten (24.3%) cases had unprotected physical contact (UPC); these included seven cases that had a bat land or crawl on them (contact with claws) and one case that touched a bat's teeth. Seven (17.1%) cases had probable UPC. Insectivorous bat teeth are extremely sharp and highly efficient for predation upon arthropod prey. Bats also have sharp claws on the end of their thumbs and feet. One of the most common bat RABV variants has an ability to replicate in non-neural cells. Questioning individuals about unprotected contact with bat teeth and claws (including a bat landing or crawling on a person) may help identify additional exposures.

Results of electron spin resonance measurement of cow teeth from a village around the Indian Nuclear Test Site and assessment of the human exposure to radiation

International Nuclear Information System (INIS)

Bhattacharjee, Deborshi; Hoshi, Masaharu; Ivannikov, Alexander; Ohtaki, Megu; Sarma, Haladhar D.

2010-01-01

A number of cow tooth samples are collected from the adjacent village of Khetolai, located 5 km from the actual Indian Nuclear Test Site in Rajasthan. The samples were processed and utilized for ESR measurements in this study by an X-band spectrometer from JEOL, Japan. The excess dose, determined by subtraction of the natural background dose from the dose absorbed by the enamel was found to the extent of 142 mGy. The intensity of ESR measurement of cow teeth, however, is lower than the human teeth in general. The detailed results obtained on dose estimation in the present study and its correlation with dose exposure for human beings as a result of nuclear test will be presented. The results of this study amply suggest that there is no direct evidence attributing to the development tumors in the cattle population of the locality. There are definitely other factors which were responsible for occurrence of such tumors and other congenital defects in the animal population in the area

Cryopreserved Dental Pulp Tissues of Exfoliated Deciduous Teeth Is a Feasible Stem Cell Resource for Regenerative Medicine

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Yamaza, Haruyoshi; Akiyama, Kentaro; Hoshino, Yoshihiro; Song, Guangtai; Kukita, Toshio; Nonaka, Kazuaki; Shi, Songtao; Yamaza, Takayoshi

2012-01-01

Human exfoliated deciduous teeth have been considered to be a promising source for regenerative therapy because they contain unique postnatal stem cells from human exfoliated deciduous teeth (SHED) with self-renewal capacity, multipotency and immunomodulatory function. However preservation technique of deciduous teeth has not been developed. This study aimed to evaluate that cryopreserved dental pulp tissues of human exfoliated deciduous teeth is a retrievable and practical SHED source for cell-based therapy. SHED isolated from the cryopreserved deciduous pulp tissues for over 2 years (25–30 months) (SHED-Cryo) owned similar stem cell properties including clonogenicity, self-renew, stem cell marker expression, multipotency, in vivo tissue regenerative capacity and in vitro immunomodulatory function to SHED isolated from the fresh tissues (SHED-Fresh). To examine the therapeutic efficacy of SHED-Cryo on immune diseases, SHED-Cryo were intravenously transplanted into systemic lupus erythematosus (SLE) model MRL/lpr mice. Systemic SHED-Cryo-transplantation improved SLE-like disorders including short lifespan, elevated autoantibody levels and nephritis-like renal dysfunction. SHED-Cryo amended increased interleukin 17-secreting helper T cells in MRL/lpr mice systemically and locally. SHED-Cryo-transplantation was also able to recover osteoporosis bone reduction in long bones of MRL/lpr mice. Furthermore, SHED-Cryo-mediated tissue engineering induced bone regeneration in critical calvarial bone-defect sites of immunocompromised mice. The therapeutic efficacy of SHED-Cryo transplantation on immune and skeletal disorders was similar to that of SHED-Fresh. These data suggest that cryopreservation of dental pulp tissues of deciduous teeth provide a suitable and desirable approach for stem cell-based immune therapy and tissue engineering in regenerative medicine. PMID:23251621

Endodontic treatment of developmental anomalies in posterior teeth: treatment of geminated/fused teeth--report of two cases.

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Tsesis, I; Steinbock, N; Rosenberg, E; Kaufman, A Y

2003-05-01

Gemination or fusion is a rare occurrence in the mandibular posterior teeth. Endodontic treatment of these teeth needs special care and attention to the bizarre anatomy. The aim of this article is to describe the problems encountered and the strategy in treating such cases. Two cases of complex endodontic treatment of fused/geminated teeth are presented. The first is an 11-year-old girl with an anomalous 'double' first mandibular molar and premolar diagnosed as having necrotic pulp with chronic apical abscess of endodontic origin; the second is a 16-year-old boy with 'double' second and supernumerary mandibular molars, who was diagnosed with irreversible pulpitis. Both cases were treated successfully in multiple appointments. The common features and treatment modalities are discussed. Failure to diagnose fused/geminated teeth leads to misdiagnosis and a treatment plan that could cause permanent damage and tooth loss. Generally, there is communication between root canal systems of fused/geminated teeth which should be treated as one entity. Use of magnification is an important aid during treatment.

Analysis of 14C and 13C in teeth provides precise birth dating and clues to geographical origin.

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Alkass, K; Buchholz, B A; Druid, H; Spalding, K L

2011-06-15

The identification of human bodies in situations when there are no clues as to the person's identity from circumstantial data, poses a difficult problem to the investigators. The determination of age and sex of the body can be crucial in order to limit the search to individuals that are a possible match. We analyzed the proportion of bomb pulse derived carbon-14 ((14)C) incorporated in the enamel of teeth from individuals from different geographical locations. The 'bomb pulse' refers to a significant increase in (14)C levels in the atmosphere caused by above ground test detonations of nuclear weapons during the cold war (1955-1963). By comparing (14)C levels in enamel with (14)C atmospheric levels systematically recorded over time, high precision birth dating of modern biological material is possible. Above ground nuclear bomb testing was largely restricted to a couple of locations in the northern hemisphere, producing differences in atmospheric (14)C levels at various geographical regions, particularly in the early phase. Therefore, we examined the precision of (14)C birth dating of enamel as a function of time of formation and geographical location. We also investigated the use of the stable isotope (13)C as an indicator of geographical origin of an individual. Dental enamel was isolated from 95 teeth extracted from 84 individuals to study the precision of the (14)C method along the bomb spike. For teeth formed before 1955 (N=17), all but one tooth showed negative Δ(14)C values. Analysis of enamel from teeth formed during the rising part of the bomb-spike (1955-1963, N=12) and after the peak (>1963, N=66) resulted in an average absolute date of birth estimation error of 1.9±1.4 and 1.3±1.0 years, respectively. Geographical location of an individual had no adverse effect on the precision of year of birth estimation using radiocarbon dating. In 46 teeth, measurement of (13)C was also performed. Scandinavian teeth showed a substantially greater depression in

In vitro study of white spot lesion: Maxilla and mandibular teeth

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Alizae Marny Mohamed

2018-04-01

Full Text Available Aim: The aim of the study was to evaluate the effect of resin infiltration on colour changes and surface roughness of artificial white spot lesions (WSLs on maxillary and mandibular premolar. Materials and methods: Sixty (60 extracted sound Maxilla (Mx and Mandibular (Mn premolars were randomly divided into 2 groups (test and control. Artificial WSLs were produced on buccal surface of teeth and were immersed in artificial saliva for 8 weeks. Colour components (L∗, a∗, b∗ and surface roughness (Sa∗ were assessed on 40 teeth using colour difference meter RD-100 and Alicona® Infinite Focus profilometer respectively. The measurements were done at baseline (T1, directly after artificial WSLs (T2, after 24 hours immersed in saliva and application of resin (T3 and immersion in artificial saliva for 1 (T4, 2 (T5, 4 (T6, 6 (T7 and 8 (T8 weeks. SEM images analysis were carried out on 20 teeth in four time points. Results: The values of L∗ (lightness, b∗ (yellow/blue and Sa∗ (surface roughness are gradually reduced to the baseline value. Whereas, the value of a∗ gradually increased with distinct treatment time to achieve the baseline value. The higher value of L∗ and Sa∗, the whiter the lesion suggesting higher degree of enamel demineralization and surface roughness. Lower L∗ values suggest a masking colour effect. Conclusion: The material produced favorable esthetics on colour and the surface roughness of teeth at distinct treatment times. It is recommended to be used to improve WSL post orthodontic treatment. Keywords: Esthetics, Infiltrant, Surface roughness, White spot lesion

Dynamics of soft tissue healing at implants and teeth: a study in a dog model.

Science.gov (United States)

Sukekava, Flávia; Pannuti, Claudio M; Lima, Luiz A; Tormena, Mariana; Araújo, Mauricio G

2016-05-01

The aim of this study was to describe and to compare some characteristics of the soft tissue healing process around teeth and implants after flap surgery. Five adult beagle dogs had their third and fourth lower premolars extracted. After 3 months, four implants per dog were placed on the healed alveolar ridge and allowed to heal non-submerged during 3 months. After 3 months, four regions characterized by one implant and one adjacent tooth were identified in each dog. One region was randomly selected and soft tissue ressective flap surgery was performed at its buccal aspect. The remaining three regions were randomly treated in an identical manner, and the dogs were sacrificed to provide biopsies representing healing intervals of 1, 2, 4, and 12 weeks. The biopsies were prepared for histological and morphological analyses. Morphometric and histometric analyses have shown that the gingival tissues surrounding teeth were completely healed after a 4-week interval. However, it took from 4 to 12 weeks for the peri-implant mucosa to heal completely. The healing process around teeth and implants follows a similar sequence of events. Nevertheless, the complete process of healing and maturation of the peri-implant tissues takes longer than around teeth. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Evaluation of Metal Ion Concentration in Hard Tissues of Teeth in Residents of Central Poland

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Piotr Wychowanski

2017-01-01

Full Text Available Objectives. The aim of the study was an assessment of the content of trace elements in enamel and dentin of teeth extracted in patients residing in urban and agricultural areas of Poland. Methods. The study included 30 generally healthy patients with retained third molars. 65 samples of enamel and dentin from individuals living in urban areas and 85 samples of enamel and dentin from individuals living in agricultural areas were prepared. The content of manganese, lead, cadmium, and chromium in the studied enamel and dentin samples from retained teeth was determined by Graphite Furnace Atomic Absorption Spectrometry. In the process of statistical hypothesis testing, the level of significance was assumed at α=0.05. Results. A comparative analysis of the data showed that enamel and dentin of inhabitants of industrialized areas contain significantly higher amounts of lead and cadmium than hard tissues of teeth in residents of agricultural areas and comparable amounts of manganese and chromium. Significance. It appears that hard tissues of retained teeth may constitute valuable material for assessment of long-term environmental exposure to metal ions. The study confirms that the risk of exposure to heavy metals depends on the place of residence and environmental pollution.

Microprobe analysis of teeth by synchrotron radiation: environmental contamination

International Nuclear Information System (INIS)

Pinheiro, T.; Carvalho, M.L.; Casaca, C.; Barreiros, M.A.; Cunha, A.S.; Chevallier, P.

1999-01-01

An X-ray fluorescence set-up with microprobe capabilities, installed at the Laboratoire pour l'Utilisation du Rayonnement Electromagnetique (LURE) synchrotron (France) was used for elemental determination in teeth. To evaluate the influence of living habits in dental elemental composition nine teeth collected post-mortem were analysed, five from a miner and four from a fisherman. All teeth from the fisherman were healthy. From the miner some teeth were carious and one of them was filled with metallic amalgam. Teeth were sliced under the vertical plane and each slice was scanned from the root to the enamel for elemental profile determination. The synchrotron microprobe resolution was of 100 μm and incident photons of 18 keV energy were used. The elemental concentration values found suggest heterogeneity of the teeth material. Moreover, the distinct profiles for Mn, Sr, Br and Pb were found when teeth from the miner and from the fisherman are compared which can be associated with dietary habits and environmental influence. Higher concentrations of Mn and Sr were found for the fisherman teeth. In addition, Br was only observed in this group of teeth. Pb levels are higher for the miner teeth in particular for dentine regions. The influence of amalgam, such as, increase of Zn and Hg contents in the teeth material, is only noticed for the immediate surroundings of the treated cavity

Tips for splinting traumatised teeth

LENUS (Irish Health Repository)

Leith, Rona

2017-10-01

A splint is required when teeth are mobile or need to be repositioned following a traumatic injury. The aim of splinting is to stabilise the injured tooth and maintain its position throughout the splinting period, improve function and provide comfort. Current best practice guidelines from the International Association for Dental Traumatology (IADT) recommend splinting for luxated, avulsed, root fractured and traumatically loosened permanent teeth.1,2 Splinting of primary teeth is usually not feasible. In general, the prognosis of a traumatised tooth is determined by the type of injury rather than the type of splint.3 However, correct splinting is important to maximise healing of the soft and hard tissues, and prevent further injury.1-6

Tips for splinting traumatised teeth

LENUS (Irish Health Repository)

Leith, Rona

2017-11-01

A splint is required when teeth are mobile or need to be repositioned following a traumatic injury. The aim of splinting is to stabilise the injured tooth and maintain its position throughout the splinting period, improve function and provide comfort. Current best practice guidelines from the International Association for Dental Traumatology (IADT) recommend splinting for luxated, avulsed, root fractured and traumatically loosened permanent teeth.1,2 Splinting of primary teeth is usually not feasible. In general, the prognosis of a traumatised tooth is determined by the type of injury rather than the type of splint.3 However, correct splinting is important to maximise healing of the soft and hard tissues, and prevent further injury.1

X radiation effects on the wound healing process after tooth extraction. Histological study in rats

International Nuclear Information System (INIS)

Miguel, R.M.; Santos Pinto, R. dos; Okamoto, T.; Santos Pinto, M.C. dos

1988-01-01

The X radiation effects on the wound healing process after teeth extractions are studied histologically. Albino rats are employed. After their right upper incisors were extracted, they were divided into groups of 20 animals each. With exception of the group I (control), 24 hours after teeth extractions the groups II, III and IV received X radiation, respectively, in the dosage of 75,125 and 175 R. The rats were sacrificed in group of 4, at 3, 6, 9,15 and 21 postoperative days and a histological study is done. (M.A.C.) [pt

Bilateral en-masse distalization of maxillary posterior teeth with skeletal anchorage: a case report

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Saeed Noorollahian

Full Text Available ABSTRACT Objective: The aim of this study was to introduce a new method for bilateral distal movement of the entire maxillary posterior segment. Case report: A 17-year-old girl with Class I skeletal malocclusion (end-to-end molar relationships, deviated midline and space deficiency for left maxillary canine was referred for orthodontic treatment. She did not accept maxillary first premolars extraction. A modified Hyrax appliance (Dentaurum Ispringen, Germany was used for bilateral distalization of maxillary posterior teeth simultaneously. Expansion vector was set anteroposteriorly. Posterior legs of Hyrax were welded to first maxillary molar bands. All posterior teeth on each side consolidated with a segment of 0.017 × 0.025-in stainless steel wire from the buccal side. Anterior legs of Hyrax were bent into eyelet form and attached to the anterior palate with two mini-screws (2 × 10 mm (Jeil Medical Corporation Seoul, South Korea. Hyrax opening rate was 0.8 mm per month. Lateral cephalometric radiographs were used to evaluate the extent of distal movement. 3.5-mm distalization of posterior maxillary teeth was achieved in five months. Results: A nearly bodily distal movement without anchorage loss was obtained. Conclusion: The mini-screw-supported modified Hyrax appliance was found to be helpful for achieving en-masse distal movement of maxillary posterior teeth.

Re-interventions after restoring teeth-Mining an insurance database.

Science.gov (United States)

Raedel, Michael; Hartmann, Andrea; Priess, Heinz-Werner; Bohm, Steffen; Samietz, Stefanie; Konstantinidis, Ioannis; Walter, Michael H

2017-02-01

The aim of this study was to examine re-interventions after restorative treatment. The data was collected from the digital database of a major German national health insurance company. Only permanent teeth were observed. Placing a permanent restoration other than a crown regardless of involved surfaces and material was the study intervention. The data did not allow for a differentiation between fillings and inlays that were estimated only a very small portion of the restorations. Success was defined as not undergoing any restorative re-intervention with fillings or inlays on the same tooth (primary outcome) and assessed with Kaplan-Meier survival analyses over four years. An additional analysis was conducted rating "crowning" and "extraction" of respective teeth as target events. Differences were tested with the Log-Rank-test. A multivariate Cox regression analyses was carried out. A total of 17,024,344 restorations placed in 4,825,408 anterior teeth and 9,973,177 posterior teeth could be traced. Focussing on the primary outcome re-intervention, the cumulative four-year success rate was 69.9% for one surface restorations, 74.8% for two surface restorations, 66.6% for three surface restorations and 61.0% for four surface and more extended restorations. These differences were significant (prestorations, 67.5% for two surface restorations, 63.0% for three surface restorations and 55.8% for four surface and more extended restorations. The number of restoration surfaces as well as the tooth position remained significant in the multivariate Cox regression. The sustainability of restorative dental treatment under the terms and conditions of the German national health insurance system shows room for improvement. From a public health perspective, special focus should be laid on primary and secondary prevention to minimize the restorative treatment need. This study shows that re-interventions are observed regularly after restorative treatment. Therefore, preventive and

Non-syndrome multiple supernumerary teeth in Nigerians.

Science.gov (United States)

Umweni, A A; Osunbor, G E N

2002-09-01

The present study was carried out to ascertain frequency of multiple supernumerary teeth not associated with syndrome in Nigerians. A total of 13 patients comprising of 10 males (76.92%) and 3 female (23.07%) representing 0.098% of the study population had multiple supernumerary teeth. Multiple supernumerary teeth without any associated systemic diseases or syndrome are rare as reported by BLUMENTHAL (3) RUHLMAN and NEELY (17), KANTOR et al. (10) is not the case in this study. The maxillary region has the highest frequency of occurrence with 12 times (66.67%) followed by the mandibular premolar region with 4 times (22.22%) while maxillary premolar and mandibular anterior region shared (5.55%) respectively. The conical and tuberculate types of supernumerary teeth were found in the midline region, while the supplemental supernumerary teeth were more in the mandibular premolar region with 12 (70.58%) follow by maxillary midline 4 (23.52%) and the lower incisor region 1 (5.88%) which is in consonant with WINTER and BROOK (2), STAFNE (19) NAZIF, FUTALO ZULLO (15). The role of genetics in the aetiology of multiple supernumerary teeth as found in this study, the occurrence of supernumerary teeth on two brothers and a daughter to one of the affected brothers, tends, to suggest an autosomal dominant mode of inheritance and the challenges to management by the orthodontists are discussed.

The gothic arch tracing and the upper canine teeth as guides in the positioning of upper posterior teeth.

Science.gov (United States)

el-Gheriani, A S; Davies, A L; Winstanley, R B

1989-09-01

The relationship between the position of the buccal cusps of the natural upper posterior teeth and the distance between the lateral arms of the Gothic arch tracing or the distance between the upper canine teeth has been found to be constant to within +/- 2 mm. This may be of value when setting up artificial teeth for denture patients, enabling them to be positioned close to the natural predecessors.

Characterization of ancient teeth and bones from animal and pre-historic human by nuclear methods

International Nuclear Information System (INIS)

Pimjun, Surapong; Chongkum, Somporn; Asvavinijkulchai, Chanchai; Khaweerat, Sasiphan; Pramankij, Somsak; Subhavan, Vadhana

2004-01-01

The search for the evidence of the oldest homonid in Thailand was carried out in the upper northern part of the country consisting of Lampang, Chiang Mai, Phayao, Phrae, Nan, Chiang Rai and Mae Hong Son and Lampang was set up as a center. Three nuclear analytical techniques, i.e. X-ray fluorescence using X-ray tube and isotopic sources, neutron activation analysis and low-background gamma spectroscopy were employed to investigate the samples. The results of elemental composition in fossilised teeth can be used to classify the type of human and animal as it is related to the dietary behaviour. The relationship between elements in fossils and soil or rock can be used to identify the location where the fossils came from. The level of natural radioactivity in soil samples from different locations will be helpful in defining the surveyed region. All of the knowledge will support the development of nuclear analytical technique in archeological study. Besides, the research team found four pieces of fossils which assembled the right frontal region of a calvaria. It appears to be the first indication of a Homo Erectus partial cranial vault ever discovered in Thailand. This discovery is very important in human evolution study

Determination of /sup 90/Sr and /sup 228/Ra in human teeth by age groups and in other substances

Energy Technology Data Exchange (ETDEWEB)

Neuzil, E F; Dysart, M E [Western Washington Univ., Bellingham (USA)

1984-12-01

The total /sup 90/Sr content of human teeth peaks at a value of 0.65 pCi/g calcium in the age group of 20-30 years. It is not present in those 50 years or older. Various other substances show extensive amounts of /sup 90/Sr especially in cow bones, bone meal and dry milk. The radionuclide /sup 228/Ra (daughter of /sup 232/Th) is present at a mean level of about 0.5 pCi/g Ca in all substances tested and in all age groups, but especially high in bone meal (5.60 pCi/g Ca) and calcium lactate tablets.

Anesthetic success of 1.8ml lidocaine 2% for mandibular tooth extraction. A pilot study

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Pedro Aravena

2013-04-01

Full Text Available Aim: To determine the anesthetic effect of a 1.8ml cartridge of anesthetic lidocaine 2% with epinephrine 1:100,000 in inferior alveolar nerve block (NAI for the extraction in mandibular teeth. Material and methods: A pilot study with analitic design. Participating patients of Dental Emergency Service volunteers from Valdivia-Chile for mandibular teeth extractions attending between May and July of 2010. The anesthetic technique was performed by a dentist using only one cartridge of anesthetic to the NAI. After 15 minutes, the effect was considered effective when anesthetic not require reinforcement with additional anesthesia during extraction of teeth. We analyzed the relationship between success anesthetic effect with sex, age, diagnosis of tooth and type and level of pain observed (chi-square and logistic regression, p<0.05. Results: 62 patients were selected, of which only 47(75.8% was achieved anesthetic success. There was no statistical association with sex, age, type or dental diagnosis and perceived pain. Conclusion: Using a 1.8ml cartridge of anesthesia was effective in three of four patients treated by extraction of mandibular teeth. It suggests further research in relation to the clinical effectiveness of other anesthetics with the same dose in NAI.

Effectivity of Betel Leaf (Piper betle L. Gel Extract in Shortening Bleeding Time After Deciduous Tooth Extraction

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Regina Tedjasulaksana

2017-01-01

Full Text Available Background: As an Indonesian traditional medicine, betel leafis often used to stop nosebleed. Effective substances in betel leaves which serves to stop the bleeding is tannin. Objective: The aim of this study was to determine the effectiveness of the betel leaf ethanol extract gel shortened bleeding time after the revocation of deciduous teeth. Method: This research was conducted at the Department of Dental Nursing Clinic, Health Polytechnic Denpasar.This study is pure experimental research design with Completely Randomized Post Test Only Control Group Design. The total sample of 27 respondents were divided into a treatment group and two control groups. Anterior deciduous teeth on the physiological loose grade 3 or 4 is extracted, then the tooth socket is put pure gel for group 1 to group 2, epinephrine gel and gel ethanol extract of betel leaf for group 3. The bleeding time is calculated from the first moment the blood out until there is blood on filter paper that is placed on the tooth socket. Data were statistically analyzed with descriptive test and comparability test with One Way Anova. Result: The results showed bleeding time pure gel groups differ significantly with epinephrine group and the group of ethanol extract of betel leaf gel (p< 0.05. Bleeding time of epinephrine group did not differ significantly with betel leaf ethanol extract group (p>0.05. Conclusion: This means ethanol gel betel leaf extract can shorten bleeding after deciduous tooth extraction and it is suggested that the use of gel ethanol extract of betel leaves to cope with bleeding after tooth extraction.

Orthodontic treatment for prominent lower front teeth (Class III malocclusion) in children.

Science.gov (United States)

Watkinson, Simon; Harrison, Jayne E; Furness, Susan; Worthington, Helen V

2013-09-30

Prominent lower front teeth (termed reverse bite; under bite; Class III malocclusion) may be due to a combination of the jaw or tooth positions or both. The upper jaw (maxilla) can be too far back or the lower jaw (mandible) too far forward, or both. Prominent lower front teeth can also occur if the upper front teeth (incisors) are tipped back or the lower front teeth are tipped forwards, or both. Various treatment approaches have been described to correct prominent lower front teeth in children and adolescents. To assess the effects of orthodontic treatment for prominent lower front teeth in children and adolescents. We searched the following databases: Cochrane Oral Health Group's Trials Register (to 7 January 2013), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2012, Issue 12), MEDLINE via OVID (1946 to 7 January 2013), and EMBASE via OVID (1980 to 7 January 2013). Randomised controlled trials (RCTs) recruiting children or adolescents or both (aged 16 years or less) receiving any type of orthodontic treatment to correct prominent lower front teeth (Class III malocclusion). Orthodontic treatments were compared with control groups who received either no treatment, delayed treatment or a different active intervention. Screening of references, identification of included and excluded studies, data extraction and assessment of the risk of bias of the included studies was performed independently and in duplicate by two review authors. The mean differences with 95% confidence intervals were calculated for continuous data. Meta-analysis was only undertaken when studies of similar comparisons reported comparable outcome measures. A fixed-effect model was used. The I2 statistic was used as a measure of statistical heterogeneity. Seven RCTs with a total of 339 participants were included in this review. One study was assessed as at low risk of bias, three studies were at high risk of bias, and in the remaining three studies risk of bias

DNA detection in tooth exposed to different temperatures: An in vitro study

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Rama Raju Devaraju

2014-01-01

Full Text Available Introduction: Human identification is an important field of study and research in forensic science and aims at establishing human identity. Several biological materials such as bone, hair, a biopsy sample, saliva and blood have been employed in isolation of DNA for human identification. It is possible to obtain DNA from virtually all human body tissues with variations in the quantity and quality of the DNA extracted from each tissue. Aims and Objectives: A study was carried out in our department to detect the presence of DNA from burnt teeth samples at various temperatures and to highlight the importance of DNA obtained from tooth in identifying a deceased in fire accidents. Materials and Methods: The work included 13 extracted teeth of patients who were indicated for therapeutic extraction and those who were diagnosed clinically and radiographically with caries and periodontitis who were indicated for extraction. Out of the 13 extracted teeth, two were decayed (One had class I dental caries C 1 and the other was grossly decayed C 2 , four were periodontally compromised teeth and the other seven were therapeutically extracted. The freshly extracted teeth were immediately subjected to varying temperatures, from 100°C to 800°C using a Delta burnout furnace for 15-20 minutes. They were cryogenically crushed using a mortar and pestle to make samples of the tooth, which were analysed for DNA. Results: When teeth were incinerated from 100°C-800°C, genomic DNA was obtained only between 100°C and 300°C whereas it was not obtained above this temperature. When the teeth were incinerated from 300°C to 800°C mtDNA was extracted from 300°C to 700°C, but no DNA was obtained above 700°C. Conclusion: Teeth are good sources for DNA, even in cases where the specimens are highly decomposed.

Management of temporomandibular joint disorders caused by complication of teeth extraction

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Endang Syamsuddin

2016-06-01

Full Text Available Complicated tooth extractions may lead to various post-extraction complications, including Temporomandibular Joint Disorders (TMD. Despite of the rare incidence, a delayed treatment of the TMD will cause more problems in the future as well as increased morbidity rate. The purpose of the current study was to elaborate the symptoms as well as the management of TMD as a post tooth extraction complication. The types of TMD as a post tooth extraction complication includes dislocated condyle, osteoarthritis, fracture condyle and disc displacement. These type of complications may resulted from an extensive opening of the mouth as well as an over pressure on the mandible during tooth extraction. In relation to this, some of the TMD symptoms that might cause a certain level of interference for patients may include pain, limited mouth opening and joint sounds, with pain and limited mouth opening as the initial symptoms. The first measure of the pain management would be warm light compress around the TMJ followed by a soft diet for food intake. A definitive treatment should then be based on the diagnosis of the TMD. It is concluded that TMD may occur as a complication of a tooth extraction that initiated by pain and limited mouth opening. Immediate treatment would be pain relieve and load reduction of the Temporomandibular Joint by employing soft diet and mandibular movement restriction.

Karakterisasi stem cell pulpa gigi sulung dengan modifikasi enzim tripsin (The characterization of stem cells from human exfoliated deciduous teeth using trypsin enzym

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Tri Wijayanti Puspitasari

2014-06-01

Full Text Available Background: Now a days, treatment in dentistry, using tissue regeneration that based on the stem cells from human exfoliated deciduous teeth (SHED, grows rapidly. For several reason, the isolated and cultured SHED is difficult to be applied in Indonesia, therefore the modification is needed. This difficulties were caused by the pulp anatomy, the heterogeneous populations in the pulp chamber and the limitations of tools and materials at the laboratory. Purpose: This research was aimed to examine that the modifications of isolation and culture technique of SHEDs for characterization by using the marker of CD105. Methods: The research was experimental laboratory with the cross sectional design. The samples were the human exfoliated deciduous teeth from the children patients of Pediatric Dentistry Department of Universitas Airlangga Dental Hospital which matched the criteria. Dental pulps were isolated and cultured by using the modifications of Trypsin enzymes. Results: The healthy SHEDs could be produced from the modifications of isolation and culture and positively shown the expression of marker CD105 which were indicated by the fluorencent microscope. Conclusion: SHED which isolated and cultured by using the modified techniques, positively characterized by using marker CD105.Latar Belakang: Pengobatan kedokteran gigi berkembang dengan pesat terutama di bidang regenerasi jaringan berbasis Stem Cells from Human Exfoliated Deciduous Teeth (SHED. Di Indonesia, isolasi dan kultur SHED sulit sehingga perlu dilakukan modifikasi. Kendala ini muncul karena jaringan pulpa yang kecil, heterogen dan keterbatasan alat dan bahan di laboratorium. Tujuan: Penelitian ini bertujuan untuk meneliti modifikasi pada cara isolasi dan kultur SHED untuk karakterisasi menggunakan maker CD105. Metode: Jenis penelitian ini adalah eksperimental laboratoris dengan rancangan cross sectional. Sampel penelitian adalah gigi sulung dari pasien anak di Klinik Kedokteran Gigi Anak

Structure, attachment, replacement and growth of teeth in bluefish, Pomatomus saltatrix (Linnaeus, 1776), a teleost with deeply socketed teeth.

Science.gov (United States)

Bemis, William E; Giuliano, Anne; McGuire, Betty

2005-01-01

Tooth replacement poses many questions about development, pattern formation, tooth attachment mechanisms, functional morphology and the evolution of vertebrate dentitions. Although most vertebrate species have polyphyodont dentitions, detailed knowledge of tooth structure and replacement is poor for most groups, particularly actinopterygians. We examined the oral dentition of the bluefish, Pomatomus saltatrix, a pelagic and coastal marine predator, using a sample of 50 individuals. The oral teeth are located on the dentary and premaxillary bones, and we scored each tooth locus in the dentary and premaxillary bones using a four-part functional classification: absent (A), incoming (I), functional (F=fully ankylosed) or eroding (E). The homodont oral teeth of Pomatomus are sharp, deeply socketed and firmly ankylosed to the bone of attachment. Replacement is intraosseus and occurs in alternate tooth loci with long waves of replacement passing from rear to front. The much higher percentage of functional as opposed to eroding teeth suggests that replacement rates are low but that individual teeth are quickly lost once erosion begins. Tooth number increases ontogenetically, ranging from 15-31 dentary teeth and 15-39 premaxillary teeth in the sample studied. Teeth increase in size with every replacement cycle. Remodeling of the attachment bone occurs continuously to accommodate growth. New tooth germs originate from a discontinuous dental lamina and migrate from the lingual (dentary) or labial (premaxillary) epithelium through pores in the bone of attachment into the resorption spaces beneath the existing teeth. Pomatomus shares unique aspects of tooth replacement with barracudas and other scombroids and this supports the interpretation that Pomatomus is more closely related to scombroids than to carangoids.

The Effect of Root Coating with Titanium on Prevention of Root Resorption in Avulsed Teeth: An Animal Study

Science.gov (United States)

Heydari, Azar; Tahmasbi, Soodeh; Badiee, Mohammadreza; Izadi, SeyedSadra; Mashhadi Abbas, Fatemeh; Mokhtari, Sepideh

2016-01-01

Introduction: Tooth avulsion is a real dental emergency. If immediate replantation is not performed, the avulsed tooth may be lost due to inflammatory or replacement resorption. This animal study aimed to evaluate the bone response to the titanium coating of the root surface as an artificial barrier, and prevention of resorption of avulsed teeth. Methods and Materials: This experimental study was conducted on four male dogs. The dogs were randomly divided into two groups for assessment at two and eight weeks. Four teeth were extracted in each animal. The root surfaces of the test group were coated with a titanium layer using the Electron Beam Deposition system. After 24 h, replantation of the teeth was performed. Two animals were sacrificed after two weeks and the remaining dogs were killed after eight weeks. The presence of inflammation, inflammatory resorption, replacement resorption, periodontal regeneration, periapical granuloma and ankylosis were evaluated through histological analyses. Results: Inflammatory root resorption was not present in any tooth except one tooth in the coated group after eight weeks. Replacement resorption was noted just in three of the non-coated teeth after two weeks and two teeth after eight weeks. The McNemar's test revealed that the frequency of replacement resorption in the non-coated group was significantly higher than the coated group (P=0.031). Conclusion: Based on the results of this study, it seems that coating the root surfaces of avulsed teeth with titanium may control the replacement root resorption. PMID:27790261

Neutron activation analysis of manganese in teeth of Japanese adults

Energy Technology Data Exchange (ETDEWEB)

Sasaki, Emiko [Nihon Univ., Tokyo. School of Dentistry

1982-01-01

In an investigation of the manganese (Mn) content of teeth in Japanese adults, neutron activation analysis was carried out of caries-free teeth, carious teeth and unerupted teeth gathered from three different districts of Japan. Regular logarithmic distribution of Mn in the dentin suggested that Mn had not been taken into account as an essential element of the teeth. Results of the study revealed no difference in Mn content among these districts, and between the caries-free teeth and the carious teeth, both in enamel and dentin. The Mn content of the enamel was about two times higher than that of the dentin.

PIXE analysis of trace elements in cetacean teeth

International Nuclear Information System (INIS)

Mitani, Yoko; Arai, Nobuaki; Sakamoto, Wataru; Yoshida, Koji

1997-01-01

PIXE was adopted for analysis of trace elements in teeth of two species of cetaceans, sperm whale (Physeter microcephalus) and pantropical spotted dolphin (Stenella attenuata). The analyses were performed along with the growth layer of the teeth, which is formed annually, suitable for age determination. Mn, Fe, Cu, Zu and Sr were detected in the teeth of sperm whale and pantropical spotted dolphin. Among these trace elements, gradual increase was observed for Zn/Ca ratio in the sperm whale's teeth. (author)

Complex aesthetic treatment on anterior maxillary teeth with malposition

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Febriastuti Febriastuti

2008-12-01

Full Text Available Background: Complex aesthetic treatment on anterior teeth involves more than one caries tooth with malformed shape and malposition. Purpose: The purpose of this paper is to find the alternative treatment for anterior maxillary teeth with malposition. Case: In this case, a 25 year-old man with a peg shaped teeth and caries on several teeth and malposition can be treated with complex aesthetic treatment. Case management: Endodontic pulpectomy treatment on anterior maxillary teeth and post construction with splint porcelain fused to metal crowns on 11, 12, and 21, 22 to correct the shape and position into normal position. Conclusion: Malformed and malpositioned teeth with caries can be treated with complex aesthetic treatment.

Examination of lead content in school children's teeth

Energy Technology Data Exchange (ETDEWEB)

Yamaga, M; Omori, K; Tozawa, T; Abe, K

1972-11-01

The results of examination on the relationship between air pollution by lead in auto exhaust and lead content of teeth of schoolchildren living in highly polluted, moderately polluted, and nonpolluted areas in Kanagawa Prefecture in 1968 are reported. The specimens were milk teeth which have fallen out and teeth in caries which were pulled out. The 177 specimens were brushed well, washed with distilled water and dried to be wet-calcined. Because of no difference of lead content between boys and girls teeth, the examination was carried on combined specimens. The findings were: (1) lead content was significantly higher in teeth of children in heavily and moderately polluted areas than in those in nonpolluted areas; (2) the lead content by area and by age showed lower values in older children in highly and nonpolluted areas. In general, the lead content of teeth was higher in children living in more polluted areas suggesting the effect of environmental pollution.

The Pb isotopic record of historical to modern human lead exposure

International Nuclear Information System (INIS)

Kamenov, George D.; Gulson, Brian L.

2014-01-01

Human teeth and bones incorporate trace amounts of lead (Pb) from the local environment during growth and remodeling. Anthropogenic activities have caused changes in the natural Pb isotopic background since historical times and this is reflected in the Pb isotopes of historical European teeth. Lead mining and use increased exponentially during the last century and the isotopic compositions of modern human teeth reflect the modern anthropogenic Pb. USA teeth show the most radiogenic Pb and Australian teeth show the least radiogenic Pb, a result of different Pb ores used in the two regions. During the last century the Australian Pb was exported to Europe, Asia, South America, and Africa, resulting in swamping of the local environmental Pb signal by the imported Pb. As a result, the modern human teeth in Europe show a significant drop to lower isotopic values compared with historical times. Similarly, modern human teeth in other regions of the world show similar Pb isotopic ratios to modern European teeth reflecting the Pb imports. The specific pattern of human Pb exposure allows us to use the Pb isotopic signal recorded in the skeleton as a geo-referencing tool. As historical European teeth show a distinct Pb signal, we can identify early European skeletal remains in the New World and likely elsewhere. In modern forensic investigations we can discriminate to some extent Eastern Europeans from Western and Northern Europeans. Australians can be identified to some extent in any region in the world, although there is some overlap with Western European individuals. Lead isotopes can be used to easily identify foreigners in the USA, as modern USA teeth are distinct from any other region of the world. By analogy, USA individuals can be identified virtually in any other region of the world. - Highlights: • We present high-precision Pb isotope data for historical and modern human teeth. • Human teeth reflect human Pb exposure since historical times. • Modern teeth show

The Pb isotopic record of historical to modern human lead exposure

Energy Technology Data Exchange (ETDEWEB)

Kamenov, George D., E-mail: kamenov@ufl.edu [Department of Geological Sciences, University of Florida, 241 Williamson Hall, Gainesville, FL 32611 (United States); Gulson, Brian L. [Graduate School of the Environment, Faculty of Science, Macquarie University, Sydney, NSW 2109 (Australia)

2014-08-15

Human teeth and bones incorporate trace amounts of lead (Pb) from the local environment during growth and remodeling. Anthropogenic activities have caused changes in the natural Pb isotopic background since historical times and this is reflected in the Pb isotopes of historical European teeth. Lead mining and use increased exponentially during the last century and the isotopic compositions of modern human teeth reflect the modern anthropogenic Pb. USA teeth show the most radiogenic Pb and Australian teeth show the least radiogenic Pb, a result of different Pb ores used in the two regions. During the last century the Australian Pb was exported to Europe, Asia, South America, and Africa, resulting in swamping of the local environmental Pb signal by the imported Pb. As a result, the modern human teeth in Europe show a significant drop to lower isotopic values compared with historical times. Similarly, modern human teeth in other regions of the world show similar Pb isotopic ratios to modern European teeth reflecting the Pb imports. The specific pattern of human Pb exposure allows us to use the Pb isotopic signal recorded in the skeleton as a geo-referencing tool. As historical European teeth show a distinct Pb signal, we can identify early European skeletal remains in the New World and likely elsewhere. In modern forensic investigations we can discriminate to some extent Eastern Europeans from Western and Northern Europeans. Australians can be identified to some extent in any region in the world, although there is some overlap with Western European individuals. Lead isotopes can be used to easily identify foreigners in the USA, as modern USA teeth are distinct from any other region of the world. By analogy, USA individuals can be identified virtually in any other region of the world. - Highlights: • We present high-precision Pb isotope data for historical and modern human teeth. • Human teeth reflect human Pb exposure since historical times. • Modern teeth show

Anticancer potential of Hericium erinaceus extracts against particular human cancer cell lines

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Younis AM

2017-06-01

Full Text Available Cancer is a leading cause of death worldwide. Cancer resulted in 8.2 million human deaths in 2012. It is expected that annual cancer cases will rise from 14 million in 2013 to 22 million within the next two decades. Mushrooms are extensively used as nutritional supplements in many countries. Moreover, mushrooms have many medicinal properties, including anticancer activity. In this study, the anticancer activity of different polar and non-polar extracts of Hericium erinaceus were evaluated against different human cancer cell lines including human liver carcinoma (Hep G2, the human colonic epithelial carcinoma (HCT 116, the human cervical cancer cells (HeLa and the human breast adenocarcinoma (MCF-7 using 3-(4,5-Dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide (MTT assay. Furthermore, as a control, the cytotoxicity effect of the different extracts were tested against isolated mouse hepatocytes. It was observed that the extracts by water and methanol from fresh and lyophilized fruiting bodies of H. erinaceus had the strongest anticancer effect. In contrast, the extracts by ether and ethyl acetate from mycelia and broth of H. erinaceus showed lower anticancer activity against the tested carcinoma cell lines. The highest anticancer activity was recorded for aqueous extract of lyophilized fruiting bodies with half maximal inhibitory concentration (IC50 values of 6.1±0.2, 5.1±0.1, 5.7±0.2 and 5.8±0.3 µg/ml against Hep G2, HCT 116, HeLa and MCF-7 cells, respectively with non-significant effect on the normal mouse hepatocytes. To summarise, polar extracts of H. erinaceus can be good sources for isolating natural anticancer compounds. I recommend further chemical studies to isolate the active principles of the extract of H. erinaceus evaluated in the present.

The use of a DNA stabilizer in human dental tissues stored under different temperature conditions and time intervals

Science.gov (United States)

TERADA, Andrea Sayuri Silveira Dias; da SILVA, Luiz Antonio Ferreira; GALO, Rodrigo; de AZEVEDO, Aline; GERLACH, Raquel Fernanda; da SILVA, Ricardo Henrique Alves

2014-01-01

Objective The present study evaluated the use of a reagent to stabilize the DNA extracted from human dental tissues stored under different temperature conditions and time intervals. Material and Methods A total of 161 teeth were divided into two distinct groups: intact teeth and isolated dental pulp tissue. The samples were stored with or without the product at different time intervals and temperature. After storage, DNA extraction and genomic DNA quantification were performed using real-time PCR; the fragments of the 32 samples that represented each possible condition were analyzed to find the four pre-selected markers in STR analysis. Results The results of the quantification showed values ranging from 0.01 to 10,246.88 ng/μL of DNA. The statistical difference in the quantity of DNA was observed when the factors related to the time and temperature of storage were analyzed. In relation to the use of the specific reagent, its use was relevant in the group of intact teeth when they were at room temperature for 30 and 180 days. The analysis of the fragments in the 32 selected samples was possible irrespective of the amount of DNA, confirming that the STR analysis using an automated method yields good results. Conclusions The use of a specific reagent showed a significant difference in stabilizing DNA in samples of intact human teeth stored at room temperature for 30 and 180 days, while the results showed no justification for using the product under the other conditions tested. PMID:25141206

Performance of a gaseous detector based energy dispersive X-ray fluorescence imaging system: Analysis of human teeth treated with dental amalgam

Science.gov (United States)

Silva, A. L. M.; Figueroa, R.; Jaramillo, A.; Carvalho, M. L.; Veloso, J. F. C. A.

2013-08-01

Energy dispersive X-ray fluorescence (EDXRF) imaging systems are of great interest in many applications of different areas, once they allow us to get images of the spatial elemental distribution in the samples. The detector system used in this study is based on a micro patterned gas detector, named Micro-Hole and Strip Plate. The full field of view system, with an active area of 28 × 28 mm2 presents some important features for EDXRF imaging applications, such as a position resolution below 125 μm, an intrinsic energy resolution of about 14% full width at half maximum for 5.9 keV X-rays, and a counting rate capability of 0.5 MHz. In this work, analysis of human teeth treated by dental amalgam was performed by using the EDXRF imaging system mentioned above. The goal of the analysis is to evaluate the system capabilities in the biomedical field by measuring the drift of the major constituents of a dental amalgam, Zn and Hg, throughout the tooth structures. The elemental distribution pattern of these elements obtained during the analysis suggests diffusion of these elements from the amalgam to teeth tissues.

What are the longevities of teeth and oral implants?

DEFF Research Database (Denmark)

Holm-Pedersen, Poul; Lang, Niklaus P; Müller, Frauke

2007-01-01

To analyse tooth loss and to evaluate the longevity of healthy teeth and teeth compromised by diseases and influenced by therapy as well as that of oral implants.......To analyse tooth loss and to evaluate the longevity of healthy teeth and teeth compromised by diseases and influenced by therapy as well as that of oral implants....

Shrinkage stress compensation in composite-restored teeth: relaxation or hygroscopic expansion?

Science.gov (United States)

Meriwether, Laurel A; Blen, Bernard J; Benson, Jarred H; Hatch, Robert H; Tantbirojn, Daranee; Versluis, Antheunis

2013-05-01

Polymerization of composite restorations causes shrinkage, which deforms and thus stresses restored teeth. This shrinkage deformation, however, has been shown to decrease over time. The objective was to investigate whether this reduction was caused by hygroscopic expansion or stress relaxation of the composite/tooth complex. Extracted molars were mounted in rigid stainless steel rings with four spherical reference areas. Twelve molars were prepared with large mesioocclusodistal slots, etched, bonded, and restored with a composite material (Filtek Supreme, 3M ESPE) in two horizontal layers. Ten intact molars were the controls. The teeth were stored either in deionized water or silicone oil. They were scanned after preparation (baseline), restoration (0-week), and after 1, 2, and 4 weeks storage. Scanned tooth surfaces were aligned with the baseline using the unchanged reference areas. Cuspal flexure was calculated from lingual and buccal surface deformation. To verify that the restorations had remained bonded, dye penetration at the interfaces was assessed using basic fuchsin dye. Statistical assessment was done by ANOVA followed by Student-Newman-Keuls post hoc test (p=0.05). Substantial cuspal contraction was found for restored teeth after the composite was cured (13-14 μm cuspal flexure). After 4 weeks cuspal contraction decreased significantly for restored teeth stored in water (7.3 ± 3.2) but not for those stored in silicone oil (11.4 ± 5.0). Dye penetration of the occlusal interface was minimal in both groups (106 ± 87 and 21 ± 28 μm in water and silicone oil, respectively). The results suggest that hygroscopic expansion was the main mechanism for shrinkage stress compensation. Copyright © 2013 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

Straight, white teeth as a social prerogative.

Science.gov (United States)

Khalid, Abeer; Quiñonez, Carlos

2015-06-01

A distinguishing feature of North American society is preoccupation with self-image, as seen in the ritualistic nature of bodily practices aimed at constantly improving the body. Nowhere is this more apparent than in the prevailing fixation with straight, white teeth. While there is an ever-expanding literature on the sociology of body, very little has been written on teeth in this context. Using literature from anthropology, biology, dentistry, sociology and social psychology, this study attempts to answer: (1) Why have straight, white teeth become a beauty ideal in North American society? (2) What is the basis for this ideal? (3) How is this ideal propagated? It demonstrates that dental aesthetic tendencies are biologically, culturally and socially patterned. Concepts from the works of Pierre Bourdieu and Michel Foucault are used to illustrate how straight, white teeth contribute towards reinforcing class differences and how society exercises a disciplinary power on individuals through this ideal. It is concluded that modified teeth are linked to self and identity that are rooted in social structure. Moreover, teeth demonstrate the ways in which class differences are embodied and projected as symbols of social advantage or disadvantage. Implications on professional, public health, sociological and political levels are considered. © 2015 Foundation for the Sociology of Health & Illness.

Root canal obturation of primary teeth: Disposable injection technique

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S K Bhandari

2012-01-01

Full Text Available The aim of the study was to outline a simple, cost-effective technique for obturation of primary tooth root canals. A total of 75 primary teeth were treated in 52 subjects by the technique discussed, i.e. injecting plastic flowable material into the root canals after desired preparation, using disposable needle and syringe. All the patients were followed up for 3 years and 6 months, with no clinical or radiologic evidence of pathology or need for untimely extraction. In conclusion, the technique described is simple, economical, can be used with almost all filling materials used for the purpose, and is easy to master with minimal chances of failure.

Stable isotope ratios in hair and teeth reflect biologic rhythms.

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Otto Appenzeller

Full Text Available Biologic rhythms give insight into normal physiology and disease. They can be used as biomarkers for neuronal degenerations. We present a diverse data set to show that hair and teeth contain an extended record of biologic rhythms, and that analysis of these tissues could yield signals of neurodegenerations. We examined hair from mummified humans from South America, extinct mammals and modern animals and people, both healthy and diseased, and teeth of hominins. We also monitored heart-rate variability, a measure of a biologic rhythm, in some living subjects and analyzed it using power spectra. The samples were examined to determine variations in stable isotope ratios along the length of the hair and across growth-lines of the enamel in teeth. We found recurring circa-annual periods of slow and fast rhythms in hydrogen isotope ratios in hair and carbon and oxygen isotope ratios in teeth. The power spectra contained slow and fast frequency power, matching, in terms of normalized frequency, the spectra of heart rate variability found in our living subjects. Analysis of the power spectra of hydrogen isotope ratios in hair from a patient with neurodegeneration revealed the same spectral features seen in the patient's heart-rate variability. Our study shows that spectral analysis of stable isotope ratios in readily available tissues such as hair could become a powerful diagnostic tool when effective treatments and neuroprotective drugs for neurodegenerative diseases become available. It also suggests that similar analyses of archaeological specimens could give insight into the physiology of ancient people and animals.

Effect of cow and soy milk on enamel hardness of immersed teeth

Science.gov (United States)

Widanti, H. A.; Herda, E.; Damiyanti, M.

2017-08-01

Cow milk and soy milk have different mineral contents and this can affect the tooth remineralization process. The aim of this study was to determine the effect of cow and soy milk on immersed teeth after demineralization. Twenty-one specimens, of human maxillary premolars, were measured for enamel hardness before immersion and demineralization in orange juice. The teeth were divided into three groups (n = 7) with each group immersed in either distilled water, cow milk, or soy milk. There was a significant increase in enamel hardness in all groups (p Cow milk provided the highest increase in enamel hardness, of all the three groups, but was not able to restore the initial enamel hardness.

The effect of stem cell from human exfoliated deciduous teeth on T lymphocyte proliferation.

Science.gov (United States)

Alipour, Razieh; Adib, Minoo; Hashemi-Beni, Batool; Sadeghi, Farzaneh

2014-01-01

Mesenchymal stem cells (MSC), a specific type of adult tissue stem cell; have the immunosuppressive effects that make them valuable targets for regenerative medicine and treatment of many human illnesses. Hence, MSC have been the subject of numerous studies. The classical source of MSC is adult bone marrow (BM). Due to many shortcomings of harvesting MSC from BM, finding the alternative sources for MSC is an urgent. Stem cells from human exfoliated deciduous teeth (SHED) are relative new MSC populations that fulfill these criteria but their potential immunosuppressive effect has not been studied enough yet. Thus, in this work the effect of SHED on the proliferation of in vitro activated T lymphocytes were explored. In this study, both mitogen and alloantigen activated T cells were cultured in the presence of different numbers of SHED. In some co-cultures, activated T cells were in direct contact to MSCs and in other co-cultures; they were separated from SHED by a permeable membrane. In all co-cultures, the proliferation of T cells was measured by ELISA Bromodeoxyuridine proliferation assay. In general, our results showed that SHED significantly suppress the proliferation of activated T cells in a dose-dependent manner. Moreover, the suppression was slightly stronger when MSCs were in physical contact to activated T cells. This study showed that SHED likewise other MSC populations can suppress the activation of T lymphocytes, which can be used instead of BM derived MSCs in many investigational and clinical applications.

External root resorption during orthodontic treatment in root-filled teeth and contralateral teeth with vital pulp: A clinical study of contributing factors.

Science.gov (United States)

Lee, Yun Ju; Lee, Tae Yeon

2016-01-01

There is a lack of research to support the belief that root canal treatment can be considered for stopping or decreasing external apical root resorption (EARR). There is conflicting evidence as to whether root-filled teeth are more or less likely to experience EARR after orthodontic treatment. The purpose of this study was to compare the degree of EARR of root-filled teeth with that of contralateral teeth with vital pulp after fixed orthodontic treatment. The study sample consisted of 35 patients aged 25.23 ± 4.92 years who had at least 1 root-filled tooth before orthodontic treatment. Digital panoramic radiographs of each patient taken before and after orthodontic treatment were used to measure the EARR. The Student t test for matched pairs and the Pearson correlation analysis were applied. The mean EARR values were 0.22 (0.14, 0.35) for root-filled teeth and 0.87 (0.59, 1.31) for contralateral teeth with vital pulp, indicating significantly less EARR for root-filled teeth compared with the contralateral teeth with vital pulp after orthodontic treatment. EARR was influenced by the patient's age, treatment duration, treatment type, and periapical pathosis, but not by tooth type and sex. Root-filled teeth appear to be associated with significantly less EARR than are contralateral teeth with vital pulp. This study suggests that the possible complication of EARR in root-filled teeth may not be an important consideration in orthodontic treatment planning, and root canal treatment can be considered for stopping or decreasing EARR when severe EARR occurs during orthodontic treatment. Copyright © 2016 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.

FT-Raman spectroscopy, µ-EDXRF spectrometry, and microhardness analysis of the dentin of primary and permanent teeth.

Science.gov (United States)

Torres, Carolina Paes; Miranda Gomes-Silva, Jaciara; Menezes-Oliveira, Maria Angélica Hueb; Silva Soares, Luís Eduardo; Palma-Dibb, Regina Guenka; Borsatto, Maria Cristina

2018-05-01

The chemical compositions (organic and inorganic contents) and mechanical behaviors of the dentin of permanent and deciduous teeth were analyzed and compared using X-ray fluorescence spectrometry (µ-EDXRF) Fourier transform Raman spectroscopy (FT-Raman) and a microhardness test (HD). Healthy fresh human primary and permanent molars (n = 10) were selected, The buccal surfaces facing upwards were stabilized in an acrylic plate, flattened, polished, and submitted to the µ-EDXRF, FT-Raman, and HD analysis. The results of the analysis were subjected to ANOVAs and Mann-Whitney U/Student's t multiple comparisons tests. The data showed similar values for the dentin of the primary and permanent teeth in P content, organic content (amide I peak), inorganic content ( PO43- - 430 and 590), and microhardness, Nevertheless, Ca content and Ca/P weight ratio were higher, and the CO32- peak was lower in the dentin of the permanent teeth compared to primary teeth. It be concluded that despite permanent teeth showed more Ca element, both substrates showed similar behavior of chemical and physical properties. © 2018 Wiley Periodicals, Inc.

Roentgenographical observation of impacted teeth

Energy Technology Data Exchange (ETDEWEB)

Choi, Hi Sup; Ahn, Hyung Kyu [College of Dentistry, Seoul National University, Seoul (Korea, Republic of)

1972-11-15

The author observed on the impacted teeth of 11 cases from 484 full-mouth roentgenograms of dental students S.N.U. (except 3rd molar). These studies are very significant in oral surgery and orthodontic problems. Most of the impacted teeth are located in maxilla and among them 7 cases are impacted central incisors the others are lateral incisors, and cuspids. The form of impactions are vertical, horizontal and inverted positions.

"The Tempest" in an English Teapot: Colonialism and the Measure of a Man in Zadie Smith's "White Teeth"

Science.gov (United States)

Gustar, Jennifer J.

2010-01-01

Zadie Smith's "White Teeth" argues that we can take responsibility for the future if we refuse to act in thrall to the legacies of the past, which favour one human life over another, and act instead with the conviction that all lives are "lives" (Judith Butler). "White Teeth" examines the colonial legacy of violence…

Saving Single-rooted Teeth with Combined Endodontic-periodontal Lesions.

Science.gov (United States)

Pico-Blanco, Alexandre; Castelo-Baz, Pablo; Caneiro-Queija, Leticia; Liñares-González, Antonio; Martin-Lancharro, Pablo; Blanco-Carrión, Juan

2016-12-01

Teeth affected by combined endodontic-periodontal lesions are usually considered by all prognosis classifications as hopeless teeth. The development of new biomaterials combined with modern endodontic and periodontal regeneration techniques may improve dental prognosis and maintain the affected teeth. Moreover, 1 of the replacement options for those teeth, dental implants, has shown an increasing number of biological and technical complications. Five patients were included in this case series study. Full periodontal and radiographic examination revealed generalized chronic periodontitis. Moreover, endodontic-periodontal lesions affecting single-rooted teeth were detected in those patients with tissue destruction beyond the apex. After splinting those teeth, conventional endodontic and nonsurgical periodontal treatment was performed. Three months later, periodontal regeneration was applied at those teeth in order to reconstruct supporting tissues and to improve dental prognosis. After a follow-up period ranging from 14 months to 17 years, it was observed that all teeth remain asymptomatic and in normal function. No signs of apical pathosis were observed, and the periodontium was stable. All patients were included in a strict maintenance program to check the periodontal and apical status. This case series shows that it is possible to change the prognosis of teeth affected by combined endodontic-periodontal lesions, even if the periodontal support is destroyed beyond the apex. Copyright © 2016 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

[The elemental composition of teeth hard tissues depending on the state of the environment].

Science.gov (United States)

Suladze, N; Shishniashvili, T; Margvelashvili, V; Kobakhidze, K

2014-01-01

At present, great attention is paid to the origin of man-made micro elemental anomalies. To monitor the state of the environment and its effects on the human body, of great importance is the determination of the amount and distribution of various chemical elements in the dentin and enamel of the teeth. To determine the essential (Ca, Zn, Mn, Ni), conditionally essential (Rb, Ni, Sr) and toxic (Pb, Hg) trace elements in the mineralized tissues of the teeth and to identify the relationship between the elemental composition of the tooth structure and the state of the general and dental health depending on the state of the environment, we have examined 29 children aged 3-4 years who have carried out analysis of hard tissue of teeth (teeth used for remote medical reasons) for the maintenance of nine chemical elements. Children living in a relatively environmentally favorable conditions essential value and conditionally essential elements in the mineralized tissues of the teeth were within normal limits, and toxic elements slightly increased limits that differ from those of children living in environmentally disadvantaged areas. In particular, these essential elements were significantly reduced (except for zinc), as indicators of toxic elements - mercury and lead, increased by 12.5% and 44.5%, respectively, which is clearly reflected on the state of dental health because noted decompensated form of tooth decay. Thus, deviations in a state of general and dental health of children associated with an imbalance of macro-and microelements in the mineralized tissues of the teeth.

226Ra-induced dental changes: a comparative microradiographic study of human and beagle dog

International Nuclear Information System (INIS)

Morgan, J.P.; Pool, R.R.; Farnham, J.E.; Miyabayashi, T.

1984-01-01

Comparison of microradiographs made from thin sections of teeth from human and the Beagle dog show a similar pattern of change dependent on age of exposure and duration of exposure prior to death or extraction. The pattern of change consisted of the presence of remodeling units of alveolar bone that extended across the gomphosis and involved the cementum and dentine. This pattern of change is not described as a normal aging change in either humans or the Beagle dog. 2 tables

Natal teeth in an infant with congenital hypothyroidism

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C Venkatesh

2011-01-01

Full Text Available Teeth erupting at birth are referred to as natal teeth. It is a common and benign finding in the neonatal period. However, they may be associated with genetic syndromes like Ellis Van Creveld syndrome and Hallermann-Streiff syndrome. We report here a case of natal teeth in an infant with congenital hypothyroidism.

Assisted eruption of impacted teeth into an alveolar bone graft in a patient with cleft lip and palate.

Science.gov (United States)

Peamkaroonrath, Chonthicha; Manosudprasit, Montien; Godfrey, Keith

2008-11-01

To assist the eruption of impacted upper teeth into an alveolar bone graft in a patient with a unilateral cleft lip and palate. An 8-year-old Thai boy with left unilateral complete cleft lip and palate had the chief complaint of anterior crossbite. He presented with a mild skeletal 3, dental Class III subdivision malocclusion, anterior crossbite, left unilateral posterior crossbite, moderate crowding in the upper arch with impaction of upper the left lateral incisor (tooth 22) and canine (tooth 23). In the first phase of treatment the posterior crossbite was corrected with a removable appliance with a 3-way screw. In the second phase the impacted teeth were surgically exposed, moved into the alveolar bone graft and the teeth aligned with fixed appliances. The upper left lateral incisor was extracted because of its questionable longevity. The orthodontic treatment resulted in normal overjet, overbite and an acceptable facial profile. A prosthesis replaced tooth 22. Forced eruption of impacted teeth can be carried out successfully in the cleft patients after an appropriate treatment plan has been formulated and following preparation of alveolar bone graft in the cleft site.

Displacement of teeth without and with bonded fixed orthodontic retainers: 3D analysis using triangular target frames and optoelectronic motion tracking device.

Science.gov (United States)

Chakroun, Firas; Colombo, Vera; Lie Sam Foek, Dave; Gallo, Luigi Maria; Feilzer, Albert; Özcan, Mutlu

2018-06-06

The objective of this study was to evaluate the anterior tooth movement without and with bonded fixed orthodontic retainers under incremental loading conditions. Six extracted mandibular anterior human teeth were embedded in acrylic resin in True Form I Arch type and 3D reconstruction of Digital Volume Tomography (DVT) images (0.4 mm 3 voxels) were obtained. The anatomy of each tooth was segmented and digitally reconstructed using 3D visualization software for medical images (AMIRA, FEI SVG). The digital models of the teeth were repositioned to form an arch with constant curvature using a CAD software (Rhinoceros) and a base holder was designed fitting the shape of the roots. The clearance between the roots and their slot in the holder was kept constant at 0.3 mm to replicate the periodontal ligament thickness. The holder and the teeth were then manufactured by 3D printing (Objet Eden 260VS, Stratasys) using a resin material for dental applications (E = 2-3 GPa). The 3D-printed teeth models were then positioned in the holder and the root compartments were filled with silicone. The procedure was repeated to obtain three identical arch models. Each model was tested for tooth mobility by applying force increasing from 5 to 30 N with 5 N increments applied perpendicular on the lingual tooth surface on the incisal one third (crosshead speed: 0.1 mm/s). The teeth on each model were first tested without retainer (control) and subsequently with the bonded retainers (braided bonded retainer wire; Multi-strand 1 × 3 high performance wire, 0.022″ × 0.016″). Tooth displacement was measured in terms of complicance (F/Δ movement) (N/mm) using custom-built optoelectronic motion tracking device (OPTIS) (accuracy: 5 µm; sampling rate: 200 Hz). The position of the object was detected through three LEDs positioned in a fixed triangular shape on a metal support (Triangular Target Frame). The measurements were repeated for three times for each tooth

Estimating Gear Teeth Stiffness

DEFF Research Database (Denmark)

Pedersen, Niels Leergaard

2013-01-01

The estimation of gear stiffness is important for determining the load distribution between the gear teeth when two sets of teeth are in contact. Two factors have a major influence on the stiffness; firstly the boundary condition through the gear rim size included in the stiffness calculation...... and secondly the size of the contact. In the FE calculation the true gear tooth root profile is applied. The meshing stiffness’s of gears are highly non-linear, it is however found that the stiffness of an individual tooth can be expressed in a linear form assuming that the contact length is constant....

Malocclusion (Misaligned Teeth)

Science.gov (United States)

... and Dental Disorders Malocclusion Causes Treatment More Information Medical Dictionary Also of Interest (Quiz) Biology of the Mouth Additional Content Medical News Malocclusion ˌmal-ə-ˈklü-zhən (Misaligned Teeth) ...

Photoacoustic imaging of teeth for dentine imaging and enamel characterization

Science.gov (United States)

Periyasamy, Vijitha; Rangaraj, Mani; Pramanik, Manojit

2018-02-01

Early detection of dental caries, cracks and lesions is needed to prevent complicated root canal treatment and tooth extraction procedures. Resolution of clinically used x-ray imaging is low, hence optical imaging techniques such as optical coherence tomography, fluorescence imaging, and Raman imaging are widely experimented for imaging dental structures. Photoacoustic effect is used in photon induced photoacoustic streaming technique to debride the root canal. In this study, the extracted teeth were imaged using photoacoustic tomography system at 1064 nm. The degradation of enamel and dentine is an indicator of onset of dental caries. Photoacoustic microscopy (PAM) was used to study the tooth enamel. Images were acquired using acoustic resolution PAM system. This was done to identify microscopic cracks and dental lesion at different anatomical sites (crown and cementum). The PAM tooth profile is an indicator of calcium distribution which is essential for demineralization studies.

External and Intrinsic Signatures in Human Teeth to Assist Forensic Identification Work

OpenAIRE

Alkass, Kanar

2011-01-01

In forensic medicine, dead victim identification constitutes an important task for forensic professionals including forensic pathologists, anthropologists, and odontologists. If no clues are at hand regarding the identity of the deceased, whether it is a victim of a mass disaster or a suspect homicide case, it is vital to know when a person died, and to know the sex and age of the decedent in order to limit the search for possible matching persons. In paper I, teeth from ...

226Ra concentration in the teeth of habitants of areas with high level of natural radioactivity in Ramsar

International Nuclear Information System (INIS)

Aghamiri, S. Mahmoud Reza; Ghorbani, Zahra; Darafsheh, Arash; Torabzadeh, Hasan; Fathivand, Ali Asghar; Minuchehr, Abdulhamid; Jalinoos, Alireza

2006-01-01

The level of natural radiation in some regions of Ramsar, a northern coastal city of Iran, is known to be among the highest levels of natural radiation in the world. 226 Ra existing in high concentrations in the soil of this region is washed by underground water and transferred to the surface. In this way, 226 Ra enters the food chain of residents and substitutes within the hard body tissues of humans. 226 Ra is one of the so-called bone seekers as its metabolic processes in the human body are similar to calcium and remains in hard tissues of body because of its long half-life, and being an α emitter causes dangerous effects on human health. The purpose of this study is to determine the concentration of 226 Ra in the teeth of residents of these high-level natural radiation areas, compared with a control group. Thirteen teeth in five groups were studied as the case group and thirteen teeth in five corresponding control groups were inspected. The mean values of the activity of 226 Ra in the case group and in the control group were 0.32 and 0.18 mBq g -1 , respectively

Targeted traction of impacted teeth with C-tube miniplates.

Science.gov (United States)

Chung, Kyu-Rhim; Kim, Yong; Ahn, Hyo-Won; Lee, Dongjoo; Yang, Dong-Min; Kim, Seong-Hun; Nelson, Gerald

2014-09-01

Orthodontic traction of impacted teeth has typically been performed using full fixed appliance as anchorage against the traction force. This conventional approach can be difficult to apply in the mixed dentition if the partial fixed appliance offers an insufficient anchor unit. In addition, full fixed appliance can induce unwanted movement of adjacent teeth. This clinical report presents 3 cases where impacted teeth were recovered in the mixed or transitional dentition with skeletal anchorage on the opposite arch without full fixed appliance. Instead, intermaxillary traction was used to bring the impacted teeth into position. With this approach, side effects on teeth and periodontal tissues adjacent to the impaction were minimized.

The Use of Tooth Particles as a Biomaterial in Post-Extraction Sockets. Experimental Study in Dogs.

Science.gov (United States)

Calvo-Guirado, José Luis; Maté-Sánchez de Val, José Eduardo; Ramos-Oltra, María Luisa; Pérez-Albacete Martínez, Carlos; Ramírez-Fernández, María Piedad; Maiquez-Gosálvez, Manuel; Gehrke, Sergio A; Fernández-Domínguez, Manuel; Romanos, Georgios E; Delgado-Ruiz, Rafael Arcesio

2018-05-06

Objectives : The objective of this study was to evaluate new bone formation derived from freshly crushed extracted teeth, grafted immediately in post-extraction sites in an animal model, compared with sites without graft filling, evaluated at 30 and 90 days. Material and Methods : The bilateral premolars P2, P3, P4 and the first mandibular molar were extracted atraumatically from six Beagle dogs. The clean, dry teeth were ground immediately using the Smart Dentin Grinder. The tooth particles obtained were subsequently sieved through a special sorting filter into two compartments; the upper container isolating particles over 1200 μm, the lower container isolated particles over 300 μm. The crushed teeth were grafted into the post-extraction sockets at P3, P4 and M1 (test group) (larger and smaller post-extraction alveoli), while P2 sites were left unfilled and acted as a control group. Tissue healing and bone formation were evaluated by histological and histomorphometric analysis after 30 and 90 days. Results : At 30 days, test site bone formation was greater in the test group than the control group ( p socket preservation.

Effect of inadequate ferrule segment location on fracture resistance of endodontically treated teeth

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Satheesh B Haralur

2018-01-01

Full Text Available Introduction: The circumferential 2 mm ferrule during the fabrication of the crown is strongly advocated for the long-term clinical success. During the routine clinical practice, the dentist encounters the endodontically treated tooth (ETT with inadequacy of the ferrule in some segment due to caries, abrasion, and erosions. The aim of this in vitro study was to investigate the consequence of inadequate segmental ferrule location on fracture strength of the root canal-treated anterior and posterior teeth. Materials and Methods: Fifty each maxillary canine and mandibular premolar intact human teeth were root canal treated and sectioned at 2 mm above the cementum-enamel junction. The teeth samples were divided into 5 groups of 10 each. The G-I and G-V samples had the 360° ferrule and complete absence of the ferrule, respectively. The G-II had the inadequate ferrule on the palatal surface, while G-III and G-IV had inadequate ferrule at buccal and proximal area. Teeth samples were subsequently restored with glass-reinforced fiber post, composite core, and full veneer metal crown. The samples were tested with universal testing machine under static load to record the fracture resistance. The acquired data were subjected to ANOVA and Tukey's post hoc statistical analysis. Results: The G-I with circumferential ferrule showed the higher fracture resistance. The teeth samples with lack of the ferrule had the least fracture resistance. Among the segmental absence of ferrule, teeth samples with lack of the proximal ferrule were least affected. Deficiency of a ferrule on the lingual wall significantly affected the fracture strength in both anterior and posterior ETT. Conclusions: The ETT with sectional inadequacy of the ferrule is significantly more effective in resisting the fracture in comparison to the complete absence of the ferrule.

Bovine teeth as a novel matrix for the control of the food chain: liquid chromatography-tandem mass spectrometry detection of treatments with prednisolone, dexamethasone, estradiol, nandrolone and seven β2-agonists.

Science.gov (United States)

Chiesa, Luca Maria; Nobile, Maria; Panseri, Sara; Biolatti, Bartolomeo; Cannizzo, Francesca Tiziana; Pavlovic, Radmila; Arioli, Francesco

2017-01-01

Veterinary drugs usually have rapid clearance rates in the liver and kidney, hampering their detection in conventional matrices such as the liver or urine. Pharmacological principles such as esterification may be applied to facilitate the administration of veterinary drugs and increase drug half-life. Prednisolone, whose therapeutic administration is regulated for food producing animals in the EU, is available in its acetate form as well as nandrolone, a banned anabolic steroid, which may be obtained as nandrolone phenylpropionate and estradiol as a benzoyl ester. While the distribution and accumulation of lipophilic and hydrophilic substances in human teeth have been well documented, studies on residues in bovine teeth are lacking. We hypothesised that analysis of bovine teeth could be used to detect both regulated and banned veterinary drugs. Steroids may be illegally used as growth promoters in food producing animals, alone or combined with β2-agonists; therefore, we developed, and validated, in accordance with the Commission Decision 2002/657/EC, two analytical confirmatory LC-MS/MS methods to detect these classes of compounds following a unique liquid extraction procedure. Finally, we analysed teeth from three male Friesian veal calves treated with intramuscular estradiol benzoate, oral prednisolone acetate or intramuscular nandrolone phenylpropionate in combination with oral ractopamine, respectively, and from seven bovines from the food chain. Teeth from treated animals were positive for their respective drugs, with the exception of nandrolone phenylpropionate. One sample from a food chain bovine was positive for isoxsuprine, one of the seven β2-agonists studied. Non-esterified forms of the steroids were not found. These results demonstrate that bovine teeth are a suitable matrix for the determination of pseudoendogenous substances or illicit administration of veterinary drugs.

Coevolutionary patterning of teeth and taste buds

Science.gov (United States)

Bloomquist, Ryan F.; Parnell, Nicholas F.; Phillips, Kristine A.; Fowler, Teresa E.; Yu, Tian Y.; Sharpe, Paul T.; Streelman, J. Todd

2015-01-01

Teeth and taste buds are iteratively patterned structures that line the oro-pharynx of vertebrates. Biologists do not fully understand how teeth and taste buds develop from undifferentiated epithelium or how variation in organ density is regulated. These organs are typically studied independently because of their separate anatomical location in mammals: teeth on the jaw margin and taste buds on the tongue. However, in many aquatic animals like bony fishes, teeth and taste buds are colocalized one next to the other. Using genetic mapping in cichlid fishes, we identified shared loci controlling a positive correlation between tooth and taste bud densities. Genome intervals contained candidate genes expressed in tooth and taste bud fields. sfrp5 and bmper, notable for roles in Wingless (Wnt) and bone morphogenetic protein (BMP) signaling, were differentially expressed across cichlid species with divergent tooth and taste bud density, and were expressed in the development of both organs in mice. Synexpression analysis and chemical manipulation of Wnt, BMP, and Hedgehog (Hh) pathways suggest that a common cichlid oral lamina is competent to form teeth or taste buds. Wnt signaling couples tooth and taste bud density and BMP and Hh mediate distinct organ identity. Synthesizing data from fish and mouse, we suggest that the Wnt-BMP-Hh regulatory hierarchy that configures teeth and taste buds on mammalian jaws and tongues may be an evolutionary remnant inherited from ancestors wherein these organs were copatterned from common epithelium. PMID:26483492

Coevolutionary patterning of teeth and taste buds.

Science.gov (United States)

Bloomquist, Ryan F; Parnell, Nicholas F; Phillips, Kristine A; Fowler, Teresa E; Yu, Tian Y; Sharpe, Paul T; Streelman, J Todd

2015-11-03

Teeth and taste buds are iteratively patterned structures that line the oro-pharynx of vertebrates. Biologists do not fully understand how teeth and taste buds develop from undifferentiated epithelium or how variation in organ density is regulated. These organs are typically studied independently because of their separate anatomical location in mammals: teeth on the jaw margin and taste buds on the tongue. However, in many aquatic animals like bony fishes, teeth and taste buds are colocalized one next to the other. Using genetic mapping in cichlid fishes, we identified shared loci controlling a positive correlation between tooth and taste bud densities. Genome intervals contained candidate genes expressed in tooth and taste bud fields. sfrp5 and bmper, notable for roles in Wingless (Wnt) and bone morphogenetic protein (BMP) signaling, were differentially expressed across cichlid species with divergent tooth and taste bud density, and were expressed in the development of both organs in mice. Synexpression analysis and chemical manipulation of Wnt, BMP, and Hedgehog (Hh) pathways suggest that a common cichlid oral lamina is competent to form teeth or taste buds. Wnt signaling couples tooth and taste bud density and BMP and Hh mediate distinct organ identity. Synthesizing data from fish and mouse, we suggest that the Wnt-BMP-Hh regulatory hierarchy that configures teeth and taste buds on mammalian jaws and tongues may be an evolutionary remnant inherited from ancestors wherein these organs were copatterned from common epithelium.

PIXE studies on teeth

International Nuclear Information System (INIS)

Chaudhri, M.A.; Ainsworth, T.

1980-01-01

The elemental composition of healthy and diseased teeth from 25 children has been determined using thick-target proton induced x-ray emission, (PIXE), analysis. Various dental hard tissues: enamel, dentine and cementum, and their junctions, as well as different parts of the same tissue, have been examined individually. A number of elements: Na, Mg, Al, P, S, Cl, Ca, V, Cr, Mn, Fe, Ni, Cu, Zn, Sr and Pb, has been determined in these dental tissues. The concentrations of some of the elements tend to vary considerably from tooth to tooth and tissue to tissue. Attempts have been made to correlate the concentrations of various elements in teeth with their health

Neanderthal teeth from Moula-Guercy, Ardèche, France.

Science.gov (United States)

Hlusko, Leslea J; Carlson, Joshua P; Guatelli-Steinberg, Debbie; Krueger, Kristin L; Mersey, Ben; Ungar, Peter S; Defleur, Alban

2013-07-01

Here we describe dental remains from a Neanderthal fossil assemblage from Moula-Guercy, France. Our report demonstrates that the Moula-Guercy hominid remains contribute important morphological, developmental, and behavioral data to understanding Neanderthal evolutionary history. We include gross comparative morphological descriptions and enamel surface microstructure and microwear data. These teeth reveal numerous characteristics that are diagnostic of Neanderthals and provide no evidence for the presence of any other hominid taxa. Enamel growth increment data from the Moula-Guercy specimens yield evidence of a Neanderthal pattern of development, although at the lower end of the range of variation. The presence of a significant number of linear enamel hypoplasias indicates that these individuals were stressed during childhood. Molar microwear data suggest that these Neanderthals did not differ significantly from modern humans in terms of the fracture properties of the food they were consuming. The incisor microwear and macro striations provide evidence that these individuals may have been using their anterior teeth as tools, similar to the practices of several modern human populations such as the Inuit, Ipiutak, and Australian Aboriginals, and reminiscent of evidence from other Neanderthals from Krapina, Croatia, as well as the 600,000 year old hominids from Sima de los Huesos, Spain. Am J Phys Anthropol 151:477-491, 2013.© 2013 Wiley Periodicals, Inc. Copyright ©2013 Wiley Periodicals, Inc.

Integrated Surgical and Orthodontic Treatment: A Twinned Teeth Dilemma

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Seema D Bargale

2015-01-01

Full Text Available Background: Twinned or geminated teeth may cause spacing, caries, aesthetic and periodontal problems which are usually seen in the anterior region. Various treatment methods can be used for correction of double teeth according to the demands of the condition. This article reports bilateral fused maxillary incisor teeth. The fused right side incisor was separated by hemisection and remaining mesial incisal margin was built using composite. Further, comprehensive orthodontic treatment was done to align the anterior maxillary teeth.

[Combination of periodontal, orthodontic and endodontic therapy in upper anterior teeth with hopeless prognosis and long-time follow-up: a case report].

Science.gov (United States)

Li, Y; Xu, L; Zhou, Y H; Ouyang, X Y; Cao, T

2017-08-18

It is complicated to decide the treatment plan of hopeless anterior teeth in esthetic zone due to severe periodontitis, periodontal-endodontic combined lesion or teeth trauma. The optional treatment plan for this kind of teeth includes retention after periodontal treatment, extraction and implant treatment, extraction and prosthodontic treatment and so on. To make an appropriate treatment plan, patients' periodontal conditions, periodontal biotype, local anatomy, esthetic demand, economic condition and social psychological status should be comprehensively considered. A combine of periodontal, endodontic and orthodontic therapy may achieve a good treatment effect in hopeless anterior teeth with severe periodontal destruction, tooth extrusion and occlusal trauma. In this case, a 20-year-old female who presented with symptoms of bleeding on brushing and upper incisors loosening for 1 month came to the Department of Periodontology, Peking University School and Hospital of Stomatology. The clinical examinations revealed that the patient's right upper incisor had signs of mobility (III°), intrusion of 1-2 mm, and probing depth (PD) of 9-10 mm. The periapical radiograph showed that the alveolar bone of right upper incisor absorbed horizontally to the apex. And the patients showed Angle II° malocclusion with II° overbite in anterior teeth and maxillary protrusion. A diagnosis of aggressive periodontitis and Angle II° malocclusion was made. The treatment of this patient lasts for 5 years which include periodontal initial therapy, orthodontic therapy, guided tissue regeneration (GTR) of right upper incisor and supportive periodontal therapy and the clinical result is fine. A hopeless upper incisor was successfully retained and the longtime clinical condition was stable. The strategy of retention of hopeless upper anterior teeth, the relationship of periodontal treatment and orthodontic treatment, and the indications of periodontal and orthodontic combined therapy were

Patient's pain perception during mandibular molar extraction with articaine: a comparison study between infiltration and inferior alveolar nerve block.

Science.gov (United States)

Bataineh, Anwar B; Alwarafi, Majid A

2016-11-01

The aim of this study was to investigate the effectiveness of a local anesthetic agent comprising of 4 % articaine with 1:100,000 adrenaline, administered through an infiltration technique prior to the extraction of mandibular permanent first molar teeth. The study adopted a split mouth approach and involved patients who needed simple extractions of permanent mandibular first molar teeth on both sides. A combination of buccal and lingual infiltrations was used on one side, while the conventional inferior alveolar nerve block (IANB) technique, with a 1.8-ml cartridge of 4 % articaine with 1:100,000 epinephrine, was administered to the other. The patients' pain perception was assessed using visual analogue scale (VAS) and verbal rating scale (VRS) after the injection, followed by extraction. As a part of the study, 104 teeth were extracted from mouths of 52 patients. The difference in pain perception was statistically insignificant (p > .05) regarding the local anesthetic injection between the two techniques. The difference in pain perception regarding the extraction between the two techniques was also statistically insignificant (p < .05). No difference in pain perception between the two techniques among the study population was noted. This indicates that the extraction of permanent mandibular first molar teeth is possible without the administration of an IANB with the use of 4 % articaine with 1:100,000 epinephrine. The buccal and lingual infiltrations are slightly less painful than the conventional IANB technique.

Analysis of human muscle extracts by proton NMR

International Nuclear Information System (INIS)

Venkatasubramanian, P.N.; Barany, M.; Arus, C.

1986-01-01

Perchloric acid extracts were prepared from pooled human muscle biopsies from patients diagnosed with scoliosis (SCOL) and cerebral palsy (CP). After neutralization with KOH and removal of perchlorate, the extracts were concentrated by freeze drying and dissolved in 2 H 2 O to contain 120 O.D. units at 280 nm per 0.5 ml. 1 H NMR spectroscopy was performed with the 5 mm probe of a Varian XL300 instrument. Creatine, lactate, carnosine, and choline were the major resonances in the one-dimensional spectra of both extracts. With creatine as reference, 2.5-fold more lactate was found in SCOL than in CP, and a much smaller difference was also found in their carnosine content. Two-dimensional COSY comparison revealed several differences between the two extracts. Taurine, N-acetyl glutamate, glycerophosphoryl choline (or phosphoryl choline) and an unidentified spot were present only in the extract from SCOL but not in that from CP. On the other hand, aspartate, hydroxy-proline, carnitine and glycerophosphoryl ethanolamine were only present in CP but absent in SCOL. Alanine, cysteine, lysine and arginine appeared in both extracts without an apparent intensity difference

Dental Anomalies in Permanent Teeth after Trauma in Primary Dentition.

Science.gov (United States)

Bardellini, Elena; Amadori, Francesca; Pasini, Stefania; Majorana, Alessandra

This retrospective study aims to evaluate the prevalence of dental anomalies in permanent teeth as a result of a trauma concerning the predecessor primary teeth. A total of 241 records of children (118 males and 123 females, mean age 3.62 ± 1.40) affected by trauma on primary teeth were analyzed. All patients were recalled to evaluate the status of the permanent successor teeth by clinical and radiographic investigations. Out of 241 patients, 106 patients (for a total of 179 traumatized primary teeth) presented at the recall. Dental anomalies on successor permanent teeth were detected in 21 patients (19.8%), for a total of 26 teeth (14.5%) and 28 anomalies. Anomalies of the eruptive process were the most observed disturbances (60.7%), followed by enamel hypoplasia (25%) and white spots (14.3%). A higher percentage of anomalies on permanent teeth was observed when trauma occurred at an age less than 36 months (38.5% of cases). Intrusive and extrusive luxation were related with the most cases of clinical disturbances in the successor permanent teeth. The results of this study highlight the risk of dental anomalies after a trauma in primary dentition, especially in early-aged children and in case of intrusive luxation.

Review of research on the mechanical properties of the human tooth

Science.gov (United States)

Zhang, Ya-Rong; Du, Wen; Zhou, Xue-Dong; Yu, Hai-Yang

2014-01-01

‘Bronze teeth' reflect the mechanical properties of natural teeth to a certain extent. Their mechanical properties resemble those of a tough metal, and the gradient of these properties lies in the direction from outside to inside. These attributes confer human teeth with effective mastication ability. Understanding the various mechanical properties of human teeth and dental materials is the basis for the development of restorative materials. In this study, the elastic properties, dynamic mechanical properties (visco-elasticity) and fracture mechanical properties of enamel and dentin were reviewed to provide a more thorough understanding of the mechanical properties of human teeth. PMID:24743065

Evaluation of crown mesiodistal diameter of permanent teeth

Directory of Open Access Journals (Sweden)

H. Ravanmehr

1994-06-01

Full Text Available The aim of this study was to evaluate mesiodistal diameter of permanent teeth and evaluating it's distribution in Iran. In current study, 850 plastery impressions or 16590 teeth were precisely measured by a digital coulis with 0.01 mm accuracy.The obtained measures of the permanent teeth are shown in table 1. Table (4 demonstrates the symmetry of left and right maxillary and mandibular teeth. Obtainedmeasurements in Table 1 were compared with Gran's measures (Table 2 which are shown in Table (3.Bolton analysis was done and results were found close to the BolType text or a website address or translate a document.ton measures. It was concluded that it is better to replace measurements of our society instead of Bolton's. Since we found minor difference with the measures of other researchers, especially for teeth anterior to first molar, using our measures in treatment plans would not bring about any problem.

Bond strength test of acrylic artificial teeth with prosthetic base

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Erna Kurnikasari

2008-07-01

Full Text Available Denture consists of acrylic artificial teeth and acrylic prothesis base bond chemically with a bond strength of 315 kgF/cm2. Most of the commercial acrylic artificial teeth do not specify their specifications and all of those acrylic artificial teeth do not include mechanical data (bond strength. The aim of this study is to discover which acrylic artificial teeth meet ADA specification no. 15. This study is a descriptive analytic study performed to 5 acrylic artificial teeth posterior brands commonly used by dentists and technicians. From each brand, 3 sample teeth were taken. The acrylic artificial teeth were prepared into a rectangular shape and were attached between acrylic prothesis base simulation and jigs. The sample was given tensile load using a Universal Testing Machine. The amount of force that causes the teeth to be fractured was recorded and the bond strength was calculated. The results of the study show that the average value for the five acrylic artificial teeth for the five brands were as followed: Brand A, 125.993 kgF/cm2; B, 188.457 kgF/cm2; C, 175.880 kgF/cm2; D, 153.373 kgF/cm2; E, 82.839 kgF/cm2. The data can be tested statistically by using One Way ANOVA test and Dunnett test (alpha = 0.05. From the study, it is concluded that the five acrylic artificial teeth have a bond strength below the ADA specification no. 15.

Numerical fatigue 3D-FE modeling of indirect composite-restored posterior teeth.

Science.gov (United States)

Ausiello, Pietro; Franciosa, Pasquale; Martorelli, Massimo; Watts, David C

2011-05-01

In restored teeth, stresses at the tooth-restoration interface during masticatory processes may fracture the teeth or the restoration and cracks may grow and propagate. The aim was to apply numerical methodologies to simulate the behavior of a restored tooth and to evaluate fatigue lifetimes before crack failure. Using a CAD-FEM procedure and fatigue mechanic laws, the fatigue damage of a restored molar was numerically estimated. Tessellated surfaces of enamel and dentin were extracted by applying segmentation and classification algorithms, to sets of 2D image data. A user-friendly GUI, which enables selection and visualization of 3D tessellated surfaces, was developed in a MatLab(®) environment. The tooth-boundary surfaces of enamel and dentin were then created by sweeping operations through cross-sections. A class II MOD cavity preparation was then added into the 3D model and tetrahedral mesh elements were generated. Fatigue simulation was performed by combining a preliminary static FEA simulation with classical fatigue mechanical laws. Regions with the shortest fatigue-life were located around the fillets of the class II MOD cavity, where the static stress was highest. The described method can be successfully adopted to generate detailed 3D-FE models of molar teeth, with different cavities and restorative materials. This method could be quickly implemented for other dental or biomechanical applications. Copyright © 2010 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

Orthodontics Align Crooked Teeth and Boost Self-Esteem

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... desktop! more... Orthodontics Align Crooked Teeth and Boost Self- esteem Article Chapters Orthodontics Align Crooked Teeth and Boost Self- esteem print full article print this chapter email this ...

Determination of Fluorine and other light elements in Syrian teeth by PIGE and PIXE techniques

International Nuclear Information System (INIS)

Bakraji, E.; Ahmad, M.; Doueer, M.

2013-01-01

The aim of this study is to determine the concentration of Fluorine in Syrian teeth collected from Southern and Coastal regions where both populations have almost similar dietary habits and similar occupational activities. The conventional PIGE method is used to determine Fluorine concentration in human teeth since its play an important role in bony and dental tissues, the low levels of Fluorine can play positive role against teeth cariosity and an inhibitor against certain enzyme systems, where high levels can cause dental Fluorosis and bone abnormalities for the bone structure. Several cations and anions have been studied in the drinking water of studied areas in order to investigate the role played by these elements and whether fluoridation within the normal levels of worldwide standard grading. Na, Mg, P and Ca concentrations have been determined in studied samples in order to compare with earlier works. (author)

Grape (Vitis vinifera) extracts protects against radiation-induced oxidative stress in human erythrocyte (RBC)

International Nuclear Information System (INIS)

Ghosh, Subhashis

2016-01-01

Ionizing radiation (IR) causes oxidative stress through the overwhelming generation of reactive oxygen species (ROS) in the living cells leading further to the oxidative damage to biomolecules. Grapes (Vitis vinifera) contain several bioactive phytochemicals and are the richest source of antioxidant. In this study, we investigated the radioprotective actions of the grape extracts of two different cultivars, including the Thompson seedless (green) and Kishmish chorni (black) in human erythrocytes. Pretreatment with grape extracts attenuates oxidative stress induced by 4 Gy-radiation in human erythrocytes in vitro. These results suggest that grape extract serve as a potential source of natural antioxidants against the IR-induced oxidative stress and also inhibit apoptosis. Furthermore, the protective action of grape depends on the source of extract (seed, skin or pulp) and type of the cultivars. Effects of grape extracts of different cultivars on protein content, Thiobarbituric acid reactive substances (TBARS) level, reduced glutathione (GSH) content and activities of Catalase, Nitrite, GST, GR in human erythrocytes against -radiation exposure at a dose of 4 Gy are investigated. The grape extracts did not appear to alter the viability of human erythrocytes. Exposure of erythrocytes to the -irradiation at a dose of 4 Gy significantly increased the extent of formation of TBARS, while decreased the level of GSH and activities of CAT, GSSG , GST, GR in the erythrocytes as compared to the non-irradiated control counterparts. This was significantly attenuated by the pretreatment with the grape seed extracts (p<0.001) and significantly with the skin extracts (p<0.05) compared to the ionizing radiation exposed group. Moreover, protection offered by the seed extracts was found significantly better than that was offered by the pulp extract of the same cultivar. In conclusion, our results suggested that the grape extracts significantly attenuated IR induced oxidative stress and