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Sample records for orthodontic bracket materials

  1. Adhesives for orthodontic bracket bonding

    Directory of Open Access Journals (Sweden)

    Déborah Daniella Diniz Fonseca

    2010-04-01

    Full Text Available The advent of acid etching, introduced by Buonocore in 1955, brought the possibility of bonding between the bracket base and enamel, contributing to more esthetic and conservative orthodontics. This direct bracket bonding technique has brought benefits such as reduced cost and time in performing the treatment, as well as making it easier to perform oral hygiene. The aim of this study was to conduct a survey of published studies on orthodontic bracket bonding to dental enamel. It was verified that resin composites and glass ionomer are the most studied and researched materials for this purpose. Resin-modified glass ionomer, with its biocompatibility, capacity of releasing fluoride and no need for acid etching on the tooth structure, has become increasingly popular among dentists. However, due to the esthetic and mechanical properties of light polymerizable resin composite, it continues to be one of the adhesives of choice in the bracket bonding technique and its use is widely disseminated.

  2. [Brackets and friction in orthodontics: experimental study].

    Science.gov (United States)

    Ben Rejeb Jdir, Saloua; Tobji, Samir; Turki, Wiem; Dallel, Ines; Khedher, Nedra; Ben Amor, Adel

    2015-09-01

    Many authors have been involved in developing brackets in order to improve the quality, stability, speed and efficiency of orthodontic treatment. In order to reduce friction between bracket and archwire, new therapeutic approaches have been devised based on novel technologies. Among these innovative techniques, self-ligating brackets are increasingly popular. SLBs can be classified into several categories according to their mode of action and their materials. We performed an experimental study to compare the friction forces generated during the sliding of orthodontic archwires made from various alloys through conventional and self-ligating brackets. Results show the favorable influence of SLBs, compared to conventional systems using elastomeric or metal ligatures, on the level of friction, particularly when shape-memory Ni-Ti archwires are used. PMID:26370596

  3. 21 CFR 872.5470 - Orthodontic plastic bracket.

    Science.gov (United States)

    2010-04-01

    ... 2010-04-01 false Orthodontic plastic bracket. 872.5470 Section 872...Therapeutic Devices § 872.5470 Orthodontic plastic bracket. (a) Identification. An orthodontic plastic bracket is a plastic device...

  4. Shear bond strength of orthodontic brackets bonded with glass ionomer cement

    OpenAIRE

    Miti? Vladimir

    2009-01-01

    Introduction. A great number of techniques have been used for bonding orthodontic brackets to the tooth surfaces. Glass ionomer cements are frequently used material for this purpose. The aim of this study was to measure the shear bond strength of orthodontic brackets bonded with glass ionomer cement Ortho Fuji LC and remained adhesive on the enamel surface after brackets debonding. Material and methods. A total of 40 extracted premolars for orthodontic reasons in different gender patients, 10...

  5. Influence of adhesion promoters and curing-light sources on the shear bond strength of orthodontic brackets

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    Claudia Tavares Machado

    2012-01-01

    Conclusions: The conventional orthodontic adhesive presented higher bond strength than the nanofilled composite, although both materials interacted similarly to the teeth. The curing-light devices tested did not influence on bond strength of orthodontic brackets.

  6. Stereomicroscope Analysis of Enamel Surface after Orthodontic Bracket Debonding

    OpenAIRE

    Mikši?, Martina; Šlaj, Mladen; Meštrovi?, Senka

    2003-01-01

    After orthodontic brackets debonding, the remaining resin has to be removed. The purpose of this study was to determine the most efficient method as well as to introduce a new method of composite removal. The study was carried out on a sample of 30 premolars, extracted for orthodontic purposes. Brackets had been bonded using the Ortho One Bisco composite resin. After the removal of brackets, samples were randomly divided into three groups of ten. Composite remnants in the first...

  7. Retrieval analysis of different orthodontic brackets: the applicability of electron microprobe techniques for determining material heterogeneities and corrosive potential

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    Alexandra Ioana Holst

    2012-08-01

    Full Text Available OBJECTIVE: The objective of this study was to investigate the applicability of micro-analytical methods with high spatial resolution to the characterization of the composition and corrosion behavior of two bracket systems. MATERIAL AND METHODS: The surfaces of six nickel-free brackets and six nickel-containing brackets were examined for signs of corrosion and qualitative surface analysis using an electron probe microanalyzer (EPMA, prior to bonding to patient's tooth surfaces and four months after clinical use. The surfaces were characterized qualitatively by secondary electron (SE images and back scattered electron (BSE images in both compositional and topographical mode. Qualitative and quantitative wavelength-dispersive analyses were performed for different elements, and by utilizing qualitative analysis the relative concentration of selected elements was mapped two-dimensionally. The absolute concentration of the elements was determined in specially prepared brackets by quantitative analysis using pure element standards for calibration and calculating correction-factors (ZAF. RESULTS: Clear differences were observed between the different bracket types. The nickel-containing stainless steel brackets consist of two separate pieces joined by a brazing alloy. Compositional analysis revealed two different alloy compositions, and reaction zones on both sides of the brazing alloy. The nickel-free bracket was a single piece with only slight variation in element concentration, but had a significantly rougher surface. After clinical use, no corrosive phenomena were detectable with the methods applied. Traces of intraoral wear at the contact areas between the bracket slot and the arch wire were verified. CONCLUSION: Electron probe microanalysis is a valuable tool for the characterization of element distribution and quantitative analysis for corrosion studies.

  8. Effect of delayed polymerization time and bracket manipulation on orthodontic bracket bonding

    Science.gov (United States)

    Ponikvar, Michael J.

    This study examined the effect of bracket manipulation in combination with delayed polymerization times on orthodontic bracket shear bond strength and degree of resin composite conversion. Orthodontics brackets were bonded to extracted third molars in a simulated oral environment after a set period of delayed polymerization time and bracket manipulation. After curing the bracket adhesive, each bracket underwent shear bond strength testing followed by micro-Raman spectroscopy analysis to measure the degree of conversion of the resin composite. Results demonstrated the shear bond strength and the degree of conversion of ceramic brackets did not vary over time. However, with stainless steel brackets there was a significant effect (p ? 0.05) of delay time on shear bond strength between the 0.5 min and 10 min bracket groups. In addition, stainless steel brackets showed significant differences related to degree of conversion over time between the 0.5 min and 5 min groups, in addition to the 0.5 min and 10 min groups. This investigation suggests that delaying bracket adhesive polymerization up to a period of 10 min then adjusting the orthodontic bracket may increase both shear bond strength and degree of conversion of stainless steel brackets while having no effect on ceramic brackets.

  9. Shear bond strength of orthodontic brackets bonded with glass ionomer cement

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    Miti? Vladimir

    2009-01-01

    Full Text Available Introduction. A great number of techniques have been used for bonding orthodontic brackets to the tooth surfaces. Glass ionomer cements are frequently used material for this purpose. The aim of this study was to measure the shear bond strength of orthodontic brackets bonded with glass ionomer cement Ortho Fuji LC and remained adhesive on the enamel surface after brackets debonding. Material and methods. A total of 40 extracted premolars for orthodontic reasons in different gender patients, 10-16 years old, were randomly divided into four groups. Using glass ionomer cement Ortho Fuji LC (Tokyo, Japan stainless steel brackets were bonded to the teeth with the average surface area of the bracket base of 14.7 mm2. The shear bond strengths were measured at a crosshead speed of 1 mm per minute, and the load applied at the time of fracture was recorded using electronic dynamometer. Remained adhesive on the enamel after bracket debonding was evaluated using the adhesive remnant index (ARI. Results. Shear bond strength had the highest value for the group where enamel was etched right before bonding bracket (9.14 MPa, than in the group 2 (7.43 MPa, while in the groups 1 (6.72 MPa and 3 (6.22 MPa, where etching was not performed, bond strength was lower. Conclusion. Shear bond strength of orthodontic brackets bonded with glass ionomer cement Ortho Fuji LC had higher values when the enamel was etched than without etching.

  10. Laser debonding of ceramic orthodontic brackets: a theoretical approach

    Science.gov (United States)

    Kearney, Kristine L.; Marangoni, Roy D.; Rickabaugh, Jeff L.

    1992-06-01

    Ceramic brackets are an esthetic substitute for conventional stainless steel brackets in orthodontic patients. However, ceramic brackets are more brittle and have higher bond strengths which can lead to bracket breakage and enamel damage during debonding. It has been demonstrated that various lasers can facilitate ceramic bracket removal. One mechanism with the laser is through the softening of the bracket adhesive. The high energy density from the laser on the bracket and adhesive can have a resultant deleterious thermal effect on the pulp of the tooth which may lead to pulpal death. A theoretical computer model of bracket, adhesive, enamel and dentin has been generated for predicting heat flow through this system. Heat fluxes at varying intensities and modes have been input into the program and the resultant temperatures at various points or nodes were determined. Further pursuit should lead to optimum parameters for laser debonding which would have minimal effects on the pulp.

  11. Does the bracket composition material influence initial biofilm formation?

    OpenAIRE

    Gustavo Antônio Martins Brandão; Antonio Carlos Pereira; Ana Maria Martins Brandão; Haroldo Amorim de Almeida; Rogério Heládio Lopes Motta

    2015-01-01

    Context: Orthodontic treatment has been reported to contribute to the development and accumulation of dental biofilm, which is commonly found on bracket and adjacent surfaces. Aims: The aim of this work is to test the hypothesis if there are differences in dental biofilm formation on the surface of orthodontic brackets according to the type of composition material. Subjects and Methods: Three bracket types (metallic, composite, and ceramic) had been evaluated. Subjects wore acrylic pa...

  12. Evaluation of Perceived Acceptability, Beauty and Value of Different Orthodontic Brackets

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    Moshkelgosha V

    2015-03-01

    Full Text Available Statement of Problem: Although different types of aesthetic brackets are introduced to orthodontic profession to reduce the complaints about the metallic braces, little studies have been done to assess patient's views regarding the attractiveness and acceptance of such brackets. Objectives: The goal of this study was to evaluate the perceived acceptability, beauty and value of different orthodontic brackets. Materials and Methods: In a cross-sectional study, three groups of subjects consisting of dental school clinic patients, specialty clinic patients, and art students were interviewed. Sample size was decided 116 in each group. The photographic images of six types of brackets which were placed in an adult mouth were shown to the subjects and they were asked to answer the questions that evaluate attractiveness by visual analog scale (VAS, acceptability of different brackets, and willingness to pay (WTP for an aesthetic bracket in comparison to a regular bracket. Reliability was measured by giving questionnaires to 20 respondents by a two-week interval. VAS rating was compared by ANOVA. Mann U Whitney and Chi-square tests were used to compare the acceptability between groups when necessary. Results: The reliability measurement results performed by ICC were 0.86 for attractiveness, 0.6 for acceptability, and 0.93 for WTP questions. Lingual brackets had the highest attractiveness rating while metal brackets were considered the lowest aesthetic appliance by all groups of the study. The acceptability of ceramic bracket was highest in all groups. While most appliances evaluated had average acceptability, the large metallic brackets were rated very low. WTP for aesthetic braces was higher in art students than other groups. Conclusions: Lingual brackets were the most attractive but had very low acceptability rate. Small metal brackets had a good acceptability rate. Large metal brackets were the least attractive and had the lowest acceptability. Parents accepted aesthetic brackets for their children even when it cost more.

  13. Physical and chemical properties of orthodontic brackets after 12 and 24 months: in situ study

    Scientific Electronic Library Online (English)

    Bernardo de Azevedo Bahia, MENDES; Ricardo Alberto Neto, FERREIRA; Matheus Melo, PITHON; Martinho Campolina Rebello, HORTA; Dauro Douglas, OLIVEIRA.

    2014-06-01

    Full Text Available Objective: The aim of this article was to assess how intraoral biodegradation influenced the surface characteristics and friction levels of metallic brackets used during 12 and 24 months of orthodontic treatment and also to compare the static friction generated in these brackets with four different [...] methods of the ligation of orthodontic wires. Material and Methods: Seventy premolar brackets as received from the manufacturer and 224 brackets that were used in previous orthodontic treatments were evaluated in this experiment. The surface morphology and the composition of the deposits found in the brackets were evaluated with rugosimetry, scanning electron microscopy, and energy dispersive X-ray spectroscopy. Friction was analyzed by applying tensile tests simulating sliding mechanics with a 0.019x0.025" steel wire. The static friction levels produced by the following ligation methods were evaluated: loosely attached steel ligature around all four bracket wings, steel ligature attached to only two wings, conventional elastomeric ligation around all 4 bracket wings, and non-conventional Slide® elastomeric ligature. Results: The results demonstrated the presence of biodegradation effects such as corrosion pits, plastic deformation, cracks, and material deposits. The main chemical elements found on these deposits were Carbon and Oxygen. The maximum friction produced by each ligation method changed according to the time of intraoral use. The steel ligature loosely attached to all four bracket wings produced the lowest friction levels in the new brackets. The conventional elastic ligatures generated the highest friction levels. The metallic brackets underwent significant degradation during orthodontic treatment, showing an increase in surface roughness and the deposit of chemical elements on the surface. Conclusion: The levels of static friction decreased with use. The non-conventional elastic ligatures were the best alternative to reduce friction.

  14. Galvanic Corrosion among Different Combination of Orthodontic Archwires and Stainless Steel Brackets

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    Farzin Heravi

    2014-06-01

    Full Text Available Introduction: The aim of this study was to assess the galvanic behavior of different bracket and archwire combinations that are commonly used in orthodontic treatments. Methods: Three types of orthodontic archwires with a diameter of 0.016×0.022 inch and 80 standard edgewise maxillary central incisor brackets were selected. Three groups consisted of different wire-bracket couples and one group was just brackets as a control group. Each group had five samples. Four brackets were then connected to each wire by elastic bands made from electrochemically neutral material. The samples were immersed into capped containers of Fusayama-Meyer artificial saliva. After six weeks, the released nickel ions were quantified via ion absorption technique. The mean and the standard deviation of all four groups were calculated and the data were compared together with Kruskal-Wallis non-parametric statistical test. Results: The highest concentration of released nickel ions was for bracket+ steel archwire and the least for the bracket without archwire. Conclusion: There were not significant differences among experimental groups, so it could be concluded that galvanic corrosion would not be a serious consideration through orthodontic treatment.  

  15. Comparison of the shear bond strength of orthodontic brackets bonded using silorane base and metacrylate base composite

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    Abdolrahim Davari

    2015-07-01

    Full Text Available Background and Aims: Orthodontic bracket failure during treatment is a common problem. With the introduction of low shrinkage composites the question is that whether: this sufficient has coefficient bond strength for bonding bracket during orthodontic treatment. The aim of this study was to compare the shear bond strength (SBS of silorane-based and metacrylate-based composites to metal brackets.   Materials and Methods: 30 human premolar teeth were collected and divided into 2 groups. In group 1, 15 orthodontic brackets were bonded using silorane-based composite, in group 2, 15 orthodontic brackets were bonded using metacrylate-based composite. The shear bond strength of each specimen was determined in an Instron machine. Amount of residual adhesive remaining on each tooth was evaluated using a stereomicroscope. Data were analyzed using T-test to compare the shear bond strength between groups and LSD method to compare the Adhesive Remnant Index (ARI scores.   Results: There was significant difference in the SBS between the test groups (P<0.001. The mean bond strength of bonding brackets to silorane-based composite was (42.42 ± 7.03 MPa, and the mean bond strength of bonding brackets metacrylate-based composite was (21.08±2.97 MPa. No significant difference in the ART was found between groups (P=0.66.   Conclusion: Silorane-based composite provided higher bond strength to orthodontic metal brackets.

  16. The effect of chemical recycling on shear bond strength of orthodontic metal brackets

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    Heravi F

    2006-01-01

    Full Text Available Background and Aim: Recycling of brackets can significantly reduce the price of fixed orthodontic appliances but if the bond is more prone to failure during treatment, this potential benefit will disappear. The aim of this study was to investigate the effect of chemical recycling on bond strength of metal orthodontic brackets and failure pattern of recycled brackets. Material and Methods: In this experimental study Instron machine was used to measure shear bond strength (SBS of brackets in two stages on 60 human maxillary first premolars using No-Mix composite. Shear bond strength and pattern of failure were compared between recycled and new brackets in two stages. Data were analyzed by ANOVA and Duncan tests. Adhesive Remnant Index was evaluated in different groups by Pearson Chi-square test. P<0.05 was considered as the limit of significance. Results: Statistical analysis showed that the mean values of SBS for new bracket group was 12.00 MPa and for recycled group and double recycled group, 9.94Mpa and 10.00 MPa respectively. A significant reduction (about 18% in bond strengths of brackets was observed at the first time of recycling. Recycling at the second time had no significant influence on the bond strength. Pattern of bond failure of these brackets showed that a great amount of residual adhesive material was remained on the teeth surfaces after debonding of recycled brackets which indicates that cleaning the teeth surfaces after debonding of recycled brackets is more time consuming. Conclusion: Based on the results of this study, before using recycled brackets, several advantages and disadvantages must be considered.

  17. Elemental composition of brazing alloys in metallic orthodontic brackets.

    Science.gov (United States)

    Zinelis, Spiros; Annousaki, Olga; Eliades, Theodore; Makou, Margarita

    2004-06-01

    The aim of this study was to assess the elemental composition of the brazing alloy of representative orthodontic brackets. The brackets examined were Gemini (3M, Unitec, Monrovia, Calif), MicroLoc (GAC, Bohemia, NY), OptiMESHxrt (Ormco, Glendora, Calif), and Ultratrim (Dentarum, Ispringen, Germany). Four metallic brackets for each brand were embedded in epoxy resin and after metallographic grinding and polishing were cleaned in a water ultrasonic bath. Scanning electron microscopy and energy-dispersive x-ray microanalysis (EDS) were used to assess the quantitative composition of the brazing alloy. Four EDS spectra were collected for each brazing alloy, and the mean value and standard deviation for the concentration of each element were calculated. The elemental composition of the brazing alloys was determined as follows (percent weight): Gemini: Ni = 83.98 +/- 1.02, Si = 6.46 +/- 0.37, Fe = 5.90 +/- 0.93, Cr = 3.52 +/- 0.34; MicroLoc: Ag = 42.82 +/- 0.18, Au = 32.14 +/- 0.65, Cu = 24.53 +/- 0.26, Mg = 1.12 +/- 0.33; OptiMESHxrt: Au = 67.79 +/- 0.97, Fe = 15.69 +/- 0.29, Ni = 13.01 +/- 0.93, Cr = 4.01 +/- 0.35; Ultratrim: Ag = 87.97 +/- 0.33, Cu = 10.51 +/- 0.45, Mg = 1.29 +/- 0.63, Zn = 1.13 +/- 0.24. The findings of this study showed that different brazing materials were used for the different brands, and thus different performances are expected during intraoral exposure; potential effects on the biological properties also are discussed. PMID:15264653

  18. Factors Affecting the Shear Bond Strength of Orthodontic Brackets – a Review of In Vitro Studies

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    Waleed Bakhadher

    2015-08-01

    Full Text Available The adhesive material used to bond orthodontic brackets to teeth should neither fail during the treatment period, resulting in treatment delays, untoward expenses or patient inconvenience nor should it damage the enamel on debonding at the end of the treatment. Although the effectiveness of a bonding system and any unfavorable effects on the enamel may be studied by conducting in-vivo studies, it is nearly impossible to independently analyze different variables that influence a specific bonding system in the oral environment. In-vitro studies, on the other hand, may utilize more standardized protocols for testing different bonding systems and materials available. Thus, the present review focused attention on in-vitro studies and made an attempt to discuss material-related, teeth-related (fluorotic vs non-fluorotic teeth and other miscellaneous factors that influences the shear bond strength of orthodontic brackets. Within the limitations of this review, using conventional acid-etch technique, ceramic brackets and bonding to non-fluorotic teeth was reported to have a positive influence on the shear bond strength of orthodontic brackets, but higher shear bond strength found on using ceramic brackets can be dangerous for the enamel.

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

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    Soodeh Tahmasbi

    2015-09-01

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

  20. The effect of phosphoric acid application time on the bond strength of orthodontic brackets

    OpenAIRE

    Miti? Vladimir; Janoševi? Mirjana

    2008-01-01

    Aim: The aim of this study was to evaluate the effect of different surface treatment intervals (15, 30 and 45 s) of 37% phosphoric acid on the bond strength of orthodontic brackets. Materials and Methods: Seventy extracted premolars, glass ionomer cement Ortho Fuji LC (GC Inc., Tokyo, Japan) and a conventional self-curing adhesive, System 1+ (Dentaurum, Inspringen, Germany) were used. Results: The obtained results suggested that the strongest bond was accomplished after enamel conditioning fo...

  1. Nuclear techniques to identify allergenic metals in orthodontic brackets

    International Nuclear Information System (INIS)

    The present study determines the elementary alloy composition of ten commercial brands of brackets, especially related to Ni, Cr, and Co metals, confirmed allergenic elements. The nuclear techniques applied in the analyses were X-ray fluorescence (XRF) - Centre National de la Recherche Scientifique, France (National Center of Scientific Research), and X-ray energy spectrometry (XRES), and Instrumental Neutron Activation Analysis (INAA) - CDTN/CNEN, Brazil. The XRES and XRF techniques identified Cr in the 10 samples analyzed and Ni in eight samples. The INAA technique identified the presence of Cr (14% to 19%) and Co (42% to 2400 ppm) in all samples. The semi-quantitative analysis performed by XRF also identified Co in two samples. The techniques were effective in the identification of metals in orthodontic brackets. The elements identified in this study can be considered one of the main reason for the allergic processes among the patients studied. This finding suggests that the patients should be tested for allergy and allergenic sensibility to metals prior to the prescription of orthodontic device. (author)

  2. Effect of Saliva pH on Shear Bond Strength of Orthodontic Brackets

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    Mohammad Hossein Toodehzaeim

    2015-10-01

    Full Text Available Objectives: The purpose of this study was to evaluate the effect of salivary pH on the shear bond strength (SBS of orthodontic brackets to tooth surface.Materials and Methods: Eighty intact premolars were randomly divided into four groups of 20.  After bonding a bracket on each tooth, the groups one to four were stored in artificial saliva at a pH of 3.8, 4.8, 5.8, and 6.8, respectively for two months. The artificial saliva solutions were refreshed weekly. Each tooth was then embedded in an acrylic block so that the crown was exposed and its buccal surface was parallel to the direction of the force during SBS testing. All brackets were debonded using Dartec universal testing machine, and the mean values of SBS in different groups were compared using one-way analysis of variance (ANOVA. Results: The mean SBS value in group 1 (pH 3.8 was significantly lower than that in other groups (P value<0.05. The differences between other groups were not sig- nificant (P>0.05.Conclusion: Decreased salivary pH, due to poor oral hygiene, and/or frequent con- sumption of acidic beverages, may be responsible for orthodontic bracket bond fail- ure.

  3. Rebonding of unused brackets with different orthodontic adhesives

    Scientific Electronic Library Online (English)

    Emigdio Enrique Orellana, Jimenez; Sérgio Paulo, Hilgenberg; Márcia Cristina, Rastelli; Gibson Luiz, Pilatti; Bruno, Orellana; Ulisses, Coelho.

    2012-04-01

    Full Text Available OBJECTIVE: To compare in vitro shear bond strength (SBS) of different orthodontic adhesives in bonding and repeatedly rebonding metal brackets, and to evaluate the bond failure site with the adhesive remnant index (ARI). METHODS: Specimens consisted of 90 extracted human first premolars, randomly di [...] vided into three groups (n=30). The adhesives Alpha Plast (AP), ConciseTM (CO) and TransbondTM XT (TB) were used in each group. Three SBS tests were performed, i.e., one at T0 (initial) and the other two at T1 and T2 (first and second rebondings, respectively), observing a 24-hour interval. The tests were performed in a Shimadzu AG-I (10kN) SBS testing machine, at a speed of 0.5 mm/min. RESULTS: SBS data were subjected to ANOVA, Tukey's test and Bonferroni test (p

  4. Effect of Four Methods of Surface Treatment on Shear Bond Strength of Orthodontic Brackets to Zirconium

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    Soghra Yassaei

    2015-10-01

    Full Text Available Objectives: Providing reliable attachment between bracket base and zirconia surface is a prerequisite for exertion of orthodontic force. The purpose of the present study was to eval- uate the effect of four zirconium surface treatment methods on shear bond strength (SBS of orthodontic brackets.Materials and Methods: One block of zirconium was trimmed into four zirconium sur- faces, which served as our four study groups and each had 18 metal brackets bonded to them. Once the glazed layer was removed, the first group was etched with 9.6% hydrofluoric acid (HF, and the other three groups were prepared by means of sandblasting and 1 W, and 2 W Er: YAG laser, respectively. After application of silane, central incisor brackets were bonded to the zirconium surfaces. The SBS values were measured by a Dartec testing ma- chine with a crosshead speed of 1 mm/min.Results: The highest SBS was achieved in the sandblasted group (7.81±1.02 MPa followed in a descending order by 2 W laser group (6.95±0.87 MPa, 1 W laser group (6.87±0.92MPa and HF acid etched group (5.84±0.78 MPa. The differences between the study groups, were statistically significant except between the laser groups (P < 0.05. Conclusion: In terms of higher bond strength and safety, sandblasting and Er: YAG laser irradiation with power output of 1 W and 2 W can be considered more appropriate alterna- tives to HF acid etching for zirconium surface treatment prior to bracket bonding.

  5. A scanning electron microscopic investigation of ceramic orthodontic brackets

    International Nuclear Information System (INIS)

    Ceramic brackets were introduced to overcome the esthetic disadvantages of stainless steel brackets. The clinical impression of these brackets is very favorable. However, the sliding mechanics used in the Straightwire (A Company, San Diego, CA, USA) system appear to produce slower tooth movements with ceramic compared to stainless steel brackets. To determine whether this was due to any obvious mechanical problem in the bracket slot, Transcend (Unitek Corporation/3M, Monrovia, CA, USA) ceramic brackets were examined by a scanning electron microscope and compared to stainless steel brackets.Consistently, large surface defects were found in the ceramic bracket slots that were not present in the metal bracket slots. These irregularities could obviously hinder the sliding mechanics of the bracket slot-archwire system and create a greater demand on anchorage. Conversely, the fitting surface of the Transcend ceramic bracket showed extremely smooth surface characteristics, and it would seem advisable for the manufacturers to incorporate this surface within the bracket slot. (author)

  6. Rebonding of unused brackets with different orthodontic adhesives

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    Emigdio Enrique Orellana Jimenez

    2012-04-01

    Full Text Available OBJECTIVE: To compare in vitro shear bond strength (SBS of different orthodontic adhesives in bonding and repeatedly rebonding metal brackets, and to evaluate the bond failure site with the adhesive remnant index (ARI. METHODS: Specimens consisted of 90 extracted human first premolars, randomly divided into three groups (n=30. The adhesives Alpha Plast (AP, ConciseTM (CO and TransbondTM XT (TB were used in each group. Three SBS tests were performed, i.e., one at T0 (initial and the other two at T1 and T2 (first and second rebondings, respectively, observing a 24-hour interval. The tests were performed in a Shimadzu AG-I (10kN SBS testing machine, at a speed of 0.5 mm/min. RESULTS: SBS data were subjected to ANOVA, Tukey's test and Bonferroni test (p<0.05. For the ARI, the Kruskal Wallis test was performed, followed by the Dunn test. The results revealed that at T0 groups AP and CO showed SBS values that were near, but above TB values; and at T1 and T2, the highest SBS values were observed for the AP group, followed by the CO and TB groups. CONCLUSION: Statistically significant differences were found in SBS between groups AP, CO and TB during bonding and repeated rebondings of unused metal brackets, with group AP achieving the highest SBS value. Regarding ARI, adhesive AP exhibited bond failure at the enamel-adhesive interface, with a higher enamel fracture frequency.

  7. The Effect of Different Soft Drinks on the Shear Bond Strength of Orthodontic Brackets

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    M Omid Khoda

    2012-01-01

    Full Text Available Objective: It is proved that acidic soft drinks that are commonly used, have an adverse effect on dental structures, and may deteriorate oral heath of our patients and orthodontic appliances. The aim of this study was to compare the effect of yoghurt drink with other soft drinks on the shear bond strength of orthodontic brackets.Materials and Methods: Seventy-five first premolar teeth extracted for orthodontic purposes were selected and standard twin metal brackets were bonded on the center of buccal surface with No-Mix composite. The teeth were thermocycled for 625 cycles and randomly divided into five groups of artificial saliva, carbonated yoghurt drink with lactic acid base, non-carbonated yoghurt drink with lactic acid base, 7 up with citric acid base and Pepsi with phosphoric acid base. In all groups, the teeth were immersed in liquid for five-minute sessions three times with equal intervening intervals for 3 months. SBS was measured by a universal testing machine with a speed of 0.5mm/min. Data was analyzed statistically by one-way ANOVA.Results: The results showed that mean values for the shear bond strength of carbonated yoghurt drinks, non-carbonated yoghurt drinks, 7up and Pepsi groups were 12.98(+_2.95, 13.26(+_4.00, 16.11(+_4.89, 14.73(+_5.10, respectively. There was no statistically significant difference among the groups (P-value= 0.238Conclusion: Soft drinks used in this study did not decrease the bond strength of the brackets bonded with this specific type of composite.

  8. In vitro peel/shear bond strength evaluation of orthodontic bracket base design

    OpenAIRE

    Willems, Guy; Carels, Carine; Verbeke, Geert

    1997-01-01

    OBJECTIVES: The adhesive capacity of 17 different bracket types was evaluated in an in vitro peel/shear test. METHODS: Silane-treated metal bars were used as substrates with all bonding being performed using the orthodontic adhesive Concise. The effect of aluminium oxide air abrasion on the bonding performance of recycled metal bracket bases was evaluated. Morphological examination of the bracket bases was carried out under scanning electron microscopy. Statistics analysis included one-way AN...

  9. Effect of bonding protocol on shear bond strength of orthodontic brackets: An in vitro study

    Scientific Electronic Library Online (English)

    Tais, Munhoz.

    2014-09-01

    Full Text Available The aim of this study was to evaluate the shear bond strength of bracket composites as a function of the application of flow adhesive prior to the composite and light curing time. Material and methods: Freshly extracted bovine permanent central incisors (50) were acid etched and divided into four g [...] roups varying the attachment protocol: (1) no adhesive, composite light-cured for 20s; (2) no adhesive, composite light-cured for 40s; (3) application of adhesive, composite light-cured for 20s; and (4) application of adhesive, composite light-cured for 40s. For comparison, a chemically cured system was used accordingly to the manufacturer instructions. The samples were stored in distilled water (37ºC) for 24 hours prior to the shear test (0,75mm/min) and the adhesive remnant index (ARI) was registered for each tooth. Results: The present in vitro findings showed that both variables, application of adhesive and light curing time, influenced the bond strength of orthodontic brackets. Brackets bonded without adhesive present lower resistance to shear forces (p=0.05) than the samples bonded with adhesive. Higher bond strength values were found for longer light curing times, though statistical difference (p=0.05) was only observed between groups (3) and (4). ARI results show lower scores for extended light curing times. Although the variables in this study significantly affect the shear bond strength of orthodontic brackets, all the experimental groups show bond strength values greater than the normally accepted in the current literature.

  10. A comparative study of metal artifacts from common metal orthodontic brackets in magnetic resonance imaging

    International Nuclear Information System (INIS)

    This study was performed to compare the metal artifacts from common metal orthodontic brackets in magnetic resonance imaging. A dry mandible with 12 intact premolars was prepared, and was scanned ten times with various types of brackets: American, 3M, Dentaurum, and Masel orthodontic brackets were used, together with either stainless steel (SS) or nickel titanium (NiTi) wires. Subsequently, three different sequences of coronal and axial images were obtained: spin-echo T1-weighted images, fast spin-echo T2-weighted images, and fluid-attenuated inversion recovery images. In each sequence, the two sequential axial and coronal images with the largest signal-void area were selected. The largest diameters of the signal voids in the direction of the X-, Y-, and Z-axes were then measured twice. Finally, the mean linear values associated with different orthodontic brackets were analyzed using one-way analysis of variation, and the results were compared using the independent t-test to assess whether the use of SS or NiTi wires had a significant effect on the images. Statistically significant differences were only observed along the Z-axis among the four different brands of orthodontic brackets with SS wires. A statistically significant difference was observed along all axes among the brackets with NiTi wires. A statistically significant difference was found only along the Z-axis between nickel-free and nickel-containing brackets. With respect to all axes, the 3M bracket was associated with smaller signal-void areas. Overall, the 3M and Dentaurum brackets with NiTi wires induced smaller artifacts along all axes than those with SS wires

  11. A comparative study of metal artifacts from common metal orthodontic brackets in magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Kajan, Zahra Dalili; Alizadeh, Ahmad; Hemmaty, Yasmin Babael; Roushan, Zahra Atrkar; Khademi, Jalil [Guilan University of Medical Sciences, Rasht (Iran, Islamic Republic of)

    2015-09-15

    This study was performed to compare the metal artifacts from common metal orthodontic brackets in magnetic resonance imaging. A dry mandible with 12 intact premolars was prepared, and was scanned ten times with various types of brackets: American, 3M, Dentaurum, and Masel orthodontic brackets were used, together with either stainless steel (SS) or nickel titanium (NiTi) wires. Subsequently, three different sequences of coronal and axial images were obtained: spin-echo T1-weighted images, fast spin-echo T2-weighted images, and fluid-attenuated inversion recovery images. In each sequence, the two sequential axial and coronal images with the largest signal-void area were selected. The largest diameters of the signal voids in the direction of the X-, Y-, and Z-axes were then measured twice. Finally, the mean linear values associated with different orthodontic brackets were analyzed using one-way analysis of variation, and the results were compared using the independent t-test to assess whether the use of SS or NiTi wires had a significant effect on the images. Statistically significant differences were only observed along the Z-axis among the four different brands of orthodontic brackets with SS wires. A statistically significant difference was observed along all axes among the brackets with NiTi wires. A statistically significant difference was found only along the Z-axis between nickel-free and nickel-containing brackets. With respect to all axes, the 3M bracket was associated with smaller signal-void areas. Overall, the 3M and Dentaurum brackets with NiTi wires induced smaller artifacts along all axes than those with SS wires.

  12. Electron microscopy analysis of different orthodontic brackets and their adhesion to the tooth enamel.

    Science.gov (United States)

    Ciocan, Delia Ioana; Stanciu, Drago?; Popescu, Manuela Anca; Miculescu, Florin; Plotog, Ioan; V?rzaru, Gauden?iu; Ciocan, Lucian Toma

    2014-01-01

    This study proposed to evaluate the surface morphology of different types of orthodontic brackets and the characteristics of their adhesion to the tooth enamel. There have been taken into study six metallic, five ceramic and one polymeric bracket from different brands (Ormco, Lancer, Leone, Damon, 3M, Ultradent, American Orthodontics, Rocky Mountain). The surface base of the each bracket it have been ESEM analyzed using scanning electron microscope Phillips XL-30 ESEM. There have been investigated several parameters that have a potential influence of the bracket-bonding agent interface joint: chemical composition, roughness, surface morphology and wideness. After ESEM analysis, the same metallic and ceramic brackets have been afterwards collated on extracted teeth and subjected to mechanical tests. After the mechanical testing, the samples were once again ESEM investigated. All fractures occurred in the area of the adhesive system, recording adhesive fractures of the tooth-composite resin and composite-bracket, cohesive fractures and both. The metallic brackets surfaces that are optima for a good adhesion is that of a mesh sand blasted and acid etched. From the esthetic brackets, the ceramic ones are superior to polymeric ones regarding bonding to teeth. PMID:25178330

  13. Influence of adhesion promoters and curing-light sources on the shear bond strength of orthodontic brackets

    OpenAIRE

    Claudia Tavares Machado; Boniek Castillo Dutra Borges; Gustavo Jales Rodrigues Araujo; Alex Jose Souza dos Santos; Fabio Roberto Dametto; Fabio Henrique de Sa Leitao Pinheiro

    2012-01-01

    Context: The effect of different curing units on bond strength of orthodontic brackets is still unclear when utilizing nanofilled composites in comparison with traditional Transbond-XT. Aim: To evaluate the influence of two adhesive promoters and two curing-light units on the shear bond strength (SBS) of orthodontic brackets. Settings and Design: The factors under study were adhesive promoters (nanofilled composite - Filtek-Z350 flowable restorative and conventional orthodontic adhesive...

  14. Effects of Two Soft Drinks on Shear Bond Strength and Adhesive Remnant Index of Orthodontic Metal Brackets

    OpenAIRE

    Soodabeh Sadat Sajadi; Gholamreza Eslami Amirabadi; Sepideh Sajadi

    2014-01-01

    Bond failure of brackets during orthodontic treatment is a common problem; which results in treatment interference, increased treatment time and prolonged clinical time for rebonding of failed brackets. The purpose of this study was to evaluate the effects of Coca-Cola and a non-alcoholic beer on the shear bond strength and adhesive remnant index (ARI) of orthodontic metal brackets in vitro.Eighty intact human premolars were divided into two experimental groups of Coca-Cola and non-alcoholic ...

  15. Comparison of Shear Bond Strength of Orthodontic Brackets Bonded to Enamel Prepared By Er:YAG Laser and Conventional Acid-Etching

    OpenAIRE

    M.H. Hosseini; F. Namvar; J. Chalipa; Saber, K.; N. Chiniforush; S Sarmadi; Mirhashemi, A.H.

    2012-01-01

    Introduction: The purpose of this study was to compare shear bond strength (SBS) of orthodontic brackets bonded to enamel prepared by Er:YAG laser with two different powers and conventional acid-etching.Materials and Methods: Forty-five human premolars extracted for orthodontic purposes were randomly assigned to three groups based on conditioning method: Group 1- conventional etching with 37% phosphoric acid; Group 2- irradiation with Er:YAG laser at 1 W; and Group 3- irradiation with Er:YAG ...

  16. Biodegradação de braquetes ortodônticos: avaliação da liberação iônica in vitro Biodegradation of orthodontic brackets: in vitro ion release

    Directory of Open Access Journals (Sweden)

    Gabriel Schmidt Dolci

    2008-06-01

    Full Text Available OBJETIVO: avaliar, in vitro, a biodegradação de aparelhos ortodônticos simulados constituídos de braquetes e fios de aço inoxidável. METODOLOGIA: a amostra foi dividida em 2 grupos, de acordo com a marca dos braquetes usados: grupo A - Dyna-Lock, 3M/Unitek (AISI 303; e grupo B - LG Edgewise Standard, American Orthodontics (AISI 316L. Os corpos-de-prova permaneceram incubados em solução salina (0,05% a 36ºC, sob agitação por um período de até 60 dias. A análise da liberação iônica foi realizada por meio de espectrofotometria de absorção atômica. O peso em massa dos braquetes também foi medido antes e após o experimento. RESULTADOS: os resultados indicaram que o grupo A apresentou maior liberação de íons ferro, níquel e cromo do que o grupo B. Além disso, os braquetes do grupo A também mostraram perda de massa, considerada outro indicativo de corrosão. CONCLUSÃO: concluiu-se que, nas condições deste experimento, os braquetes do grupo A apresentaram maior biodegradação que os acessórios do grupo B, o que pode estar associado à liga metálica e/ou ao processo de fabricação dos mesmos.OBJECTIVE: The purpose of this study was to evaluate, in vitro, the biodegradation of simulated orthodontic appliances consisting of stainless steel brackets and wires. MATERIALS AND METHODOS: The sample was divided in 2 groups, according to brackets brand: group A - Dyna-Lock, 3M/ Unitek (AISI 303; and group B - LG Edgewise Standard, American Orthodontics (AISI 316L. The specimens (simulated orthodontic appliances were incubated in saline solution (0.05%, in shake, at 36ºC, for 60 days. The ion release was detected by atomic absorption spectrophotometer. The weight of brackets was also measured before and after the test. RESULTS: The results indicated that group A released more ions iron, nickel and chromium than group B. Moreover, the brackets in group A also presented weight loss, which is considered an indicator of corrosion. CONCLUSION: It was concluded that, under the present study conditions, the brackets from group A presented a higher biodegradation than group’s B brackets, what could be associated to composition and manufacturing process of these brackets.

  17. Biodegradação de braquetes ortodônticos: avaliação da liberação iônica in vitro / Biodegradation of orthodontic brackets: in vitro ion release

    Scientific Electronic Library Online (English)

    Gabriel Schmidt, Dolci; Luciane Macedo de, Menezes; Rodrigo Matos de, Souza; Berenice Anina, Dedavid.

    2008-06-01

    Full Text Available OBJETIVO: avaliar, in vitro, a biodegradação de aparelhos ortodônticos simulados constituídos de braquetes e fios de aço inoxidável. METODOLOGIA: a amostra foi dividida em 2 grupos, de acordo com a marca dos braquetes usados: grupo A - Dyna-Lock, 3M/Unitek (AISI 303); e grupo B - LG Edgewise Standar [...] d, American Orthodontics (AISI 316L). Os corpos-de-prova permaneceram incubados em solução salina (0,05%) a 36ºC, sob agitação por um período de até 60 dias. A análise da liberação iônica foi realizada por meio de espectrofotometria de absorção atômica. O peso em massa dos braquetes também foi medido antes e após o experimento. RESULTADOS: os resultados indicaram que o grupo A apresentou maior liberação de íons ferro, níquel e cromo do que o grupo B. Além disso, os braquetes do grupo A também mostraram perda de massa, considerada outro indicativo de corrosão. CONCLUSÃO: concluiu-se que, nas condições deste experimento, os braquetes do grupo A apresentaram maior biodegradação que os acessórios do grupo B, o que pode estar associado à liga metálica e/ou ao processo de fabricação dos mesmos. Abstract in english OBJECTIVE: The purpose of this study was to evaluate, in vitro, the biodegradation of simulated orthodontic appliances consisting of stainless steel brackets and wires. MATERIALS AND METHODOS: The sample was divided in 2 groups, according to brackets brand: group A - Dyna-Lock, 3M/ Unitek (AISI 303) [...] ; and group B - LG Edgewise Standard, American Orthodontics (AISI 316L). The specimens (simulated orthodontic appliances) were incubated in saline solution (0.05%), in shake, at 36ºC, for 60 days. The ion release was detected by atomic absorption spectrophotometer. The weight of brackets was also measured before and after the test. RESULTS: The results indicated that group A released more ions iron, nickel and chromium than group B. Moreover, the brackets in group A also presented weight loss, which is considered an indicator of corrosion. CONCLUSION: It was concluded that, under the present study conditions, the brackets from group A presented a higher biodegradation than group’s B brackets, what could be associated to composition and manufacturing process of these brackets.

  18. The effects of silver coating on friction coefficient and shear bond strength of steel orthodontic brackets.

    Science.gov (United States)

    Arash, Valiollah; Anoush, Keivan; Rabiee, Sayed Mahmood; Rahmatei, Manuchehr; Tavanafar, Saeid

    2015-01-01

    Aims of the present study was to measure frictional resistance between silver coated brackets and different types of arch wires, and shear bond strength of these brackets to the tooth. In an experimental clinical research 28 orthodontic brackets (standard, 22 slots) were coated with silver ions using electroplate method. Six brackets (coated: 3, uncoated: 3) were evaluated with Scanning Electron Microscopy and Atomic Force Microscopy. The amount of friction in 15 coated brackets was measured with three different kinds of arch wires (0.019?×?0.025-in stainless steel [SS], 0.018-in stainless steel [SS], 0.018-in Nickel-Titanium [Ni-Ti]) and compared with 15 uncoated steel brackets. In addition, shear bond strength values were compared between 10 brackets with silver coating and 10 regular brackets. Universal testing machine was used to measure shear bond strength and the amount of friction between the wires and brackets. SPSS 18 was used for data analysis with t-test. SEM and AFM results showed deposition of a uniform layer of silver, measuring 8-10??m in thickness on bracket surfaces. Silver coating led to higher frictional forces in all the three types of arch wires, which was statistically significant in 0.019?×?0.025-in SS and 0.018-in Ni-Ti, but it did not change the shear bond strength significantly. Silver coating with electroplating method did not affect the bond strength of the bracket to enamel; in addition, it was not an effective method for decreasing friction in sliding mechanics. PMID:25997114

  19. Effect of various commercially available mouthrinses on shear bond strength of orthodontic metal brackets: An in vitro study

    Directory of Open Access Journals (Sweden)

    Nazeer Ahmed Meeran

    2013-01-01

    Conclusion: Alcohol containing mouthrinses affect the shear bond strength of the metal orthodontic brackets bonded with composite resin (Transbond XT in the present study, more when compared with alcohol-free mouthrinses. It is, therefore, highly advisable to avoid alcohol containing mouthrinses in patients undergoing orthodontic treatment and use alcohol-free mouthrinses as adjuncts to regular oral hygiene procedures for maintaining good enamel integrity and periodontal health, without compromising the shear bond strength of the bonded metal brackets.

  20. Gingival response in orthodontic patients: Comparative study between self-ligating and conventional brackets

    Scientific Electronic Library Online (English)

    Alejandra A, Folco; Sandra C, Benítez-Rogé; Marina, Iglesias; Diana, Calabrese; Cristina, Pelizardi; Alcira, Rosa; Marisa I, Brusca; Pedro, Hecht; María E, Mateu.

    2014-12-01

    Full Text Available Los brackets ortodoncicos contribuyen al acumulo de placa bacteriana en las superficies dentarias, debido a que dificultan la higiene oral. A diferencia de los brackets convencionales, los brackets autoligables no requieren elementos adicionales para sujetar los arcos, lo cual favoreceria la higiene [...] dentaria. El objetivo del presente trabajo fue comparar la respuesta gingival en pacientes ortodoncicos, utilizando brackets autoligables y brackets convencionales. Se estudiaron 22 pacientes, entre 16 y 30 anos, divididos en dos grupos: A, tratado con brackets autoligables, Sistema Damon) y B, tratado con brackets convencionales, Tecnica de Roth. Durante el tratamiento, se evaluaron los Indices de Placa (IP), Indice Gingival (IG) y Profundidad de Sondaje (PS) y se tomaron muestras subgingivales de las piezas 14/24 para su observacion microbiologica. En la evaluacion estadistica no se encontraron diferencias estadisticamente significativa entre los grupos A y B; p>0.05 (de los rangos con signo) y ni en los IP, IG y PS en los diferentes tiempos evaluados (Analisis de varianza de Friedman), sin embargo se observa un aumento en los indices a los 14 dias, sobre todo en autoligables. Los microorganismos se presentaron en cantidad y calidad compatible con salud el dia 0, 28 y 56; a partir del dia 14 predomina microbiota compatible con gingivitis para ambos grupos. En las muestras estudiadas el tratamiento ortodoncicos produce incremento de placa bacteriana y respuesta gingival inflamatoria, pero con terapia basica adecuada puede mantenerse la salud gingivo-lperiodontal. Los brackets autoligables y los o convencionales, produjeron respuesta gingival similar. Abstract in english Orthodontic brackets contribute to the accumulation of bacterial plaque on tooth surfaces because they hinder oral hygiene. In contrast to conventional brackets, self-ligating brackets do not require additional parts to support the arches, thus improving dental hygiene. The aim of this study was to [...] compare the gingival response in orthodontic patients wearing self-ligating or conventional brackets. A sample of 22 patients aged 16 to 30 years was divided into two groups: Group A, treated with selfligating brackets (Damon system) and Group B, treated with conventional brackets (Roth technique). The following were assessed during the treatment: Plaque Index (PI), Gingival Index (GI) and Probing Depth (PD), and sub-gingival samples were taken from teeth 14/24 for microbiological observation. No statistically significant difference was found between Groups A and B; p>0.05 (sign-ranked) or between PI, GI and PD at the different times (Friedman's Analysis of Variance), even though the indices were found to increase at 14 days, particularly for self-ligating brackets. The quantity and quality of microorganisms present were compatible with health on days 0, 28 and 56. As from day 14 there is a predominance of microbiota compatible with gingivitis in both groups. In the samples studied, orthodontic treatment increases bacterial plaque and inflammatory gingival response, but gingival-periodontal health can be maintained with adequate basic therapy. Self-ligating and conventional brackets produced similar gingival response.

  1. Effects of modifying the bonding protocol on the shear bond strength of metallic and ceramic orthodontic brackets.

    Science.gov (United States)

    Fernandes, Thais Maria Friere; Janson, Guilherme; Somensi, Joyce; Pinzan, Arnaldo; Francisconi, Paulo Afonso Silveira; Sathler, Renata; Henriques, Jose Fernando Castanha

    2012-01-01

    The purpose of this study was to evaluate the in vitro shear bond strength and failure site of metallic and ceramic orthodontic brackets with modified bonding protocols. Sixty bovine mandibular incisors with similar anatomy were selected and divided into six groups (n = 10). In the first protocol, metallic and ceramic brackets were bonded according to the manufacturers' directions (controls); in the second protocol, the step of photocuring with the primer agent was eliminated; and in the third protocol, the primer agent was applied on the tooth and on the bracket base, followed by application of the composite adhesive on the bracket base, with one-step photocure. The same orthodontic adhesive was used for all groups. Shear bond strengths were measured and adhesive remnant index scores (ARI) were determined after bracket failure. The results demonstrated similar shear bond strengths in the protocols but presented significantly greater values for the metallic groups (two-way ANOVA, P adhesion of the brackets. PMID:22313980

  2. Enamel Surface Roughness after Debonding of Orthodontic Brackets and Various Clean-Up Techniques

    Directory of Open Access Journals (Sweden)

    Farzaneh Ahrari

    2013-01-01

    Full Text Available Objective: This study aimed to evaluate enamel roughness after adhesive removal using different burs and an Er:YAG laser.Materials and Methods: The buccal surfaces of forty human premolars were sealed by two layers of nail varnish, except for a circular area of 3 mm in diameter on the middle third. The enamel surfaces were initially subjected to profilometry analysis and four parameters of surface irregularity (Ra, Rq, Rt and Rz were recorded. Following bracket bonding and debonding, adhesive remnants were removed by tungsten carbide burs in low- or high- speed handpieces (group 1 and 2, respectively, an ultrafine diamond bur (group 3 or an Er:YAG laser (250 mJ, long pulse, 4 Hz (group 4, and surface roughness parameters were measured again. Then, the buccal surfaces were polished and the third profilometry measurements were performed.Results: The specimens that were cleaned with a low speed tungsten carbide bur showed no significant difference in surface irregularity between the different treatment stages (p>0.05. Surface roughness increased significantly after clean-up with the diamond bur and the Er:YAG laser (p<0.01. In comparison between groups, adhesive removal with tungsten carbide burs at slow- or high-speed handpieces produced the lowest, while enamel clean-up with the Er:YAG laser caused the highest values of roughness measurements (P<0.05.Conclusion: Under the study conditions, application of the ultrafine diamond bur or the Er:YAG laser caused irreversible enamel damage on tooth surface, and thus these methods could not be recommended for removing adhesive remnants after debonding of orthodontic brackets.

  3. Oral bacterial adhesion forces to biomaterial surfaces constituting the bracket-adhesive-enamel junction in orthodontic treatment.

    Science.gov (United States)

    Mei, Li; Busscher, Henk J; van der Mei, Henny C; Chen, Yangxi; de Vries, Joop; Ren, Yijin

    2009-08-01

    Bacterial adhesion to biomaterial surfaces constituting the bracket-adhesive-enamel junction represents a growing problem in orthodontics, because bacteria can adversely affect treatment by causing demineralization of the enamel surface around the brackets. It is important to know the forces with which bacteria adhere to the surfaces of these junction materials, as the strength of these forces will determine how easy it will be to remove the bacteria. We compared the adhesion forces of five initially colonizing and four cariogenic strains of bacteria to an orthodontic adhesive, stainless steel, and enamel, with and without a salivary conditioning film. Adhesion forces were determined using atomic force microscopy and a bacterial probe. In the absence of a salivary conditioning film, the strongest bacterial adhesion forces occurred to the adhesive surface (-2.9 to -6.9 nN), while adhesion forces to the enamel surfaces were lowest (-0.8 to -2.7 nN). In the presence of a salivary conditioning film, adhesion forces were reduced strongly, to less than 1 nN, and the differences between the various materials were reduced. Generally, however, initial colonizers of dental hard surfaces presented stronger adhesion forces to the different materials (-4.7 and -0.6 nN in the absence and presence of a salivary conditioning film, respectively) than cariogenic strains (-1.8 and -0.5 nN). PMID:19627354

  4. Shear Bond Strength of Orthodontic Brackets Fixed with Remineralizing Adhesive Systems after Simulating One Year of Orthodontic Treatment

    Science.gov (United States)

    Bezerra, Gisele Lima; Torres, Carlos Rocha Gomes; Tonetto, Mateus Rodrigues; Borges, Alvaro Henrique; Kuga, Milton Carlos; Bandeca, Matheus Coelho; Firoozmand, Leily Macedo

    2015-01-01

    The objective of this study is to assess, in vitro, the shear bond strength of orthodontic brackets fixed with remineralizing adhesive systems submitted to thermomechanical cycling, simulating one year of orthodontic treatment. Sixty-four bovine incisor teeth were randomly divided into 4 experimental groups (n = 16): XT: Transbond XT, QC: Quick Cure, OL: Ortholite Color, and SEP: Transbond Plus Self-Etching Primer. The samples were submitted to thermomechanical cycling simulating one year of orthodontic treatment. Shear bond strength tests were carried out using a universal testing machine with a load cell of 50?KgF at 0.5?mm/minute. The samples were examined with a stereomicroscope and a scanning electron microscope (SEM) in order to analyze enamel surface and Adhesive Remnant Index (ARI). Kruskal-Wallis and Mann-Whitney (with Bonferroni correction) tests showed a significant difference between the studied groups (p < 0.05). Groups XT, QC, and SEP presented the highest values of adhesive resistance and no statistical differences were found between them. The highest frequency of failures between enamel and adhesive was observed in groups XT, QC, and OL. Quick Cure (QC) remineralizing adhesive system presented average adhesive resistance values similar to conventional (XT) and self-etching (SEP) adhesives, while remineralizing system (OL) provided the lowest values of adhesive resistance. PMID:26380371

  5. Orthodontic brackets in high field MR imaging: experimental evaluation of magnetic field interactions at 3.0 tesla; Kieferorthopaedische Brackets in der Hochfeld-Magnetresonanz-Tomographie: Experimentelle Beurteilung magnetischer Anziehungs- und Rotationskraefte bei 3 Tesla

    Energy Technology Data Exchange (ETDEWEB)

    Kemper, J.; Adam, G. [Klinik und Poliklinik fuer Diagnostische und Interventionelle Radiologie, Universitaetsklinikum Eppendorf, Hamburg (Germany); Klocke, A.; Kahl-Nieke, B. [Poliklinik fuer Kieferorthopaedie, Universitaetsklinikum Eppendorf, Hamburg (Germany)

    2005-12-15

    Purpose: To evaluate static magnetic field interactions for 32 commonly used orthodontic brackets in a 3.0 T magnetic resonance imaging (MRI) system. Materials and methods: 32 orthodontic brackets consisting of a steel alloy (n=27), a cobalt-chromium alloy (n=2), ceramic (n=1), ceramic with a steel slot (n=1), and titanium (n=1) from 13 different manufacturers were tested for magnetic field interactions in a static magnetic field at 3.0 T (Gyroscan Intera 3.0 T, Philips Medical Systems, Best, Netherlands). The magnetic deflection force F{sub Z} [mN] was evaluated by determining the deflection angle {beta}[ ] using the established deflection angle test according to the ASTM guidelines. The magnetic-field-induced rotational force F{sub rot} or torque was qualitatively determined using a 5-point grading scale (0: no torque; +4: very strong torque). Results: In 18 of the 32 brackets, the deflection angle {beta} was found to be > 45 and the translational force exceeded the gravitational force F{sub G} on the particular bracket (F{sub Z}: 1.2-45.7 mN). The translational force F{sub Z} was found to be up to 68.5 times greater than the gravitational force F{sub G} (F{sub Z}/F{sub G}: 1.4-68.5). The rotational force F{sub rot} was correspondingly high (+3/+4) for those brackets. For the remaining 14 objects, the deflection angles were < 45 and the torque measurements ranged from 0 to +2. The static magnetic field did not affect the titanium bracket and the ceramic bracket. No measurable translational and rotational forces were found. (orig.)

  6. Shear bond strength of orthodontic brackets to enamel under different surface treatment conditions

    Scientific Electronic Library Online (English)

    Matheus Melo, Pithon; Márlio Vinícius de, Oliveira; Antonio Carlos de Oliveira, Ruellas; Ana Maria, Bolognese; Fábio Lourenço, Romano.

    2007-04-01

    Full Text Available The purpose of the present study was to evaluate the shear bond strength to enamel and the adhesive remnant index (ARI) of both metallic and polycarbonate brackets bonded under different conditions. Ninety bovine permanent mandibular incisors were embedded in acrylic resin using PVC rings as molds a [...] nd assigned to 6 groups (n=15). In Groups 1 (control) and 3, metallic and polycarbonate orthodontic brackets were, respectively, bonded to the enamel surfaces using Transbond XT composite according to the manufacturer's recommendations. In Groups 2 and 4, both types of brackets were bonded to enamel with Transbond XT composite, but XT primer was replaced by the OrthoPrimer agent. In Groups 5 and 6, the polycarbonate bracket bases were sandblasted with 50-mm aluminum-oxide particle stream and bonded to the enamel surfaces prepared under the same conditions described in Groups 3 and 4, respectively. After bonding, the specimens were stored in distilled water at 37ºC for 24 hours and then submitted to shear bond strength test at a crosshead speed of 0.5 mm/min. The results (MPa) showed no statistically significant difference between Groups 4 and 6 (p>0.05). Likewise, no statistically significant differences (p>0.05) were found among Groups 1, 2, and 5, although their results were significantly lower than those of Groups 4 and 6 (p

  7. Reduction in static friction by deposition of a homogeneous diamond-like carbon (DLC) coating on orthodontic brackets.

    Science.gov (United States)

    Akaike, Shun; Hayakawa, Tohru; Kobayashi, Daishiro; Aono, Yuko; Hirata, Atsushi; Hiratsuka, Masanori; Nakamura, Yoshiki

    2015-01-01

    In orthodontics, a reduction in static friction between the brackets and wire is important to enable easy tooth movement. The aim of this study was to examine the effects of a homogeneous diamond-like carbon (DLC) coating on the whole surfaces of slots in stainless steel orthodontic brackets on reducing the static friction between the brackets and the wire. The DLC coating was characterized using Raman spectroscopy, surface roughness and contact angle measurements, and SEM observations. Rectangular stainless steel and titanium-molybdenum alloy wires with two different sizes were employed, and the static friction between the brackets and wire was measured under dry and wet conditions. The DLC coating had a thickness of approximately 1.0 ?m and an amorphous structure was identified. The results indicated that the DLC coating always led to a reduction in static friction. PMID:26632239

  8. Comparative in vitro study of the shear bond strength of brackets bonded with restorative and orthodontic resins

    OpenAIRE

    Hassan Isber; Aldrieli Regina Ambrosio; Paulo Eduardo Guedes Carvalho; Karyna Martins do Valle-Corotti; Danilo Furquim Siqueira

    2011-01-01

    The aim of this study was to evaluate the shear bond strength of brackets bonded with different restorative systems and compare it with that afforded by an established orthodontic bonding system. Seventy human bicuspids were used, divided into five different groups with 14 teeth each. Whereas a specific orthodontic bonding resin (TransbondTM XT) was used in the control group, the restorative systems Charisma, Tetric Ceram, TPH Spectrum and Z100 were used in the other four groups. Seven days a...

  9. Shear bond strength of orthodontic brackets bonded using halogen light and light-emitting diode at different debond times

    OpenAIRE

    Rebeca Di Nicoló; Maria Amelia Maximo Araujo; Levy Anderson César Alves; Rodrigo Othavio de Assunção e Souza; Daniel Maranha da Rocha

    2010-01-01

    The aim of this in vitro study was to compare the photoactivation effects of QTH (Quartz-Tungsten-Halogen) and LED (Light-Emitting Diode) on the SBS (Shear Bond Strength) of orthodontic brackets at different debond times. Seventy-two bovine lower incisors were randomly divided into two groups according to the photoactivation system used (QTH or LED). The enamel surfaces were conditioned with Transbond self-etching primer, and APC (Adhesive Pre-Coated) brackets were used in all specimens. Grou...

  10. Comparison of frictional resistance between self-ligating and conventional brackets tied with elastomeric and metal ligature in orthodontic archwires

    Scientific Electronic Library Online (English)

    Vanessa Vieira, Leite; Murilo Baena, Lopes; Alcides, Gonini Júnior; Marcio Rodrigues de, Almeida; Sandra Kiss, Moura; Renato Rodrigues de, Almeida.

    2014-06-01

    Full Text Available OBJETIVO: comparar a resistência ao atrito entre braquetes autoligáveis e braquetes convencionais, variando o tipo de fio. MÉTODOS: foram usados braquetes incisivos Abzil Kirium Capelozza e Easy Clip. Uma ligadura elastomérica ou um fio ligável de 0,010" foi usado para ligação do fio no braque [...] te Abzil. Três tipos de ligas de fio ortodôntico foram avaliadas: fio de NiTi de 0,016"; fio de NiTi de 0,016" x 0,022"; e fio de aço de 0,019" x 0,025". Dez observações foram feitas para cada combinação "braquete-fio-inclinação". Os braquetes foram montados em um aparelho especial, posicionados a 90° em relação ao fio, e testados em duas inclinações. O teste de atrito foi realizado na máquina universal de ensaios, a 5mm/min e com 10mm de deslocamento. As médias (em MPa) foram submetidas aos testes ANOVA e de Tukey, a 5% de significância. As superfícies dos fios e dos braquetes foram observadas no MEV. RESULTADOS: o braquete com amarrilhos metálicos (16,48 ± 8,31MPa) apresentou médias mais altas que o braquete com ligaduras elastoméricas (4,29 ± 2,16MPa) e o braquete autoligável (1,66 ± 1,57) (p 0,05). Nenhuma diferença estatística (p > 0,05) foi encontrada entre inclinações de zero (7,76 ± 8,46) e cinco (7,19 ± 7,93) graus. Concluão: o atrito foi influenciado pelo tipo de braquete e sistemas de ligaduras. Diferentes aspectos morfológicos foram observados para os braquetes e fios estudados. Abstract in english OBJECTIVE: To compare the frictional resistance between self-ligating and conventional brackets tied to different types of wire. MATERIAL AND METHODS : Abzil Kirium Capelozza (Pattern I) and Easy Clip (Roth prescription) incisor brackets were used. An elastomeric ligature or a ligating wire 0. [...] 10-in was used to ligate the wire to the Abzil bracket. Three types of orthodontic archwire alloys were assessed: 0.016-in NiTi wire, 0.016 x 0.021-in NiTi wire and 0.019 x 0.025-in steel wire. Ten observations were carried out for each bracket-archwire angulation combination. Brackets were mounted in a special appliance, positioned at 90 degrees in relation to the wire and tested in two angulations. Frictional test was performed in a Universal Testing Machine at 5 mm/min and 10 mm of displacement. The means (MPa) were submitted to ANOVA and Tukey's test set at 5% of significance. The surfaces of wires and brackets were observed at SEM. RESULTS: Steel-tied brackets (16.48 ± 8.31) showed higher means of frictional resistance than elastomeric-tied brackets (4.29 ± 2.16 ) and self-ligating brackets (1.66 ± 1.57) (P 0.05). No statistical differences (P > 0.05) were found between zero (7.76 ± 8.46) and five-degree (7.19 ± 7.93) angulations. CONCLUSIONS: Friction was influenced not only by the type of bracket, but also by the ligating systems. Different morphological aspects were observed for the brackets and wires studied

  11. Recycling stainless steel orthodontic brackets with Er:YAG laser – An environmental scanning electron microscope and shear bond strength study

    Science.gov (United States)

    Chacko, Prince K; Kodoth, Jithesh; John, Jacob; Kumar, Kishore

    2013-01-01

    Aim: To determine the efficiency of erbium: Yttrium aluminum garnet (Er:YAG) laser with Environmental Scanning Electron Microscope (ESEM) and shear bond strength analysis as a method of recycling stainless steel orthodontic brackets and compare with other methods of recycling. Materials and Methods: Eighty samples of extracted premolar teeth bonded to SS brackets were tested for rebonded shear bond strength after recycling by four methods and compared with a control group of 20 samples. These 80 samples were randomized into four groups which were recycled by four methods, namely, sandblasting, thermal method, adhesive grinding by tungsten carbide bur, and Er: YAG laser method. After recycling, ESEM and shear bond strength analysis were used to analyze the efficiency of the recycling methods Results: Er: YAG laser group was found to be having the greatest bond strength among the recycled brackets (8.33±2.51 followed by the sandblasting at 6.12±1.12 MPa, thermal and electropolishing at 4.44±0.95 MPa, and lastly the adhesive grinding method at 3.08±1.07 MPa. The shear bond strength of Er: YAG laser group was found to be having no statistically significant difference with that of the control group (P>0.05 and had statistical signifance with sandblasting, thermal and electropolishing and adhesive grinding groups at P>0.001. ESEM analysis showed complete removal of adhesive from the brackets recycled with Er: YAG laser which mimicked that of the control group. Conclusion: Er: YAG laser (2940 nm) was found to be the most efficient method for recycling, followed by the sandblasting, thermal, and the tungsten carbide methods, which had the least shear bond strength value and is not fit for clinical usage. PMID:24987647

  12. Alterations in plaque accumulation and gingival inflammation promoted by treatment with self-ligating and conventional orthodontic brackets

    Scientific Electronic Library Online (English)

    Mauricio de Almeida, Cardoso; Patrícia Pinto, Saraiva; Liliana Ávila, Maltagliati; Fernando Kleinübing, Rhoden; Carla Cristina Alvarenga, Costa; David, Normando; Leopoldino, Capelozza Filho.

    2015-04-01

    Full Text Available OBJETIVO: o objetivo do presente estudo foi avaliar, comparativamente, a resposta periodontal durante o tratamento ortodôntico realizado com braquetes autoligáveis e convencionais. MÉTODOS: dezesseis indivíduos, leucodermas, em dentição permanente, de ambos os sexos, com idades de 12 a 16 anos, for [...] am selecionados. Oito foram tratados com braquetes convencionais instalados na arcada inferior, e braquetes autoligáveis na arcada superior. Os outros oito indivíduos receberam braquetes autoligáveis na arcada inferior e braquetes convencionais na arcada superior. Os pacientes receberam materiais e instruções sobre higiene bucal. O índice de placa visível (IPV), o índice de sangramento gengival (ISG) e o nível de inserção clínica (NIC) foram avaliados logo após a instalação do aparelho e 30, 60 e 180 dias mais tarde. Para comparar as diferenças entre os grupos (braquetes autoligáveis e convencionais), foi utilizado o teste Mann-Whitney; para analisar o NIC em cada local de cada dente, foi utilizada a análise de variância de duas vias, seguida do teste de Tukey, com nível de significância a 5%. RESULTADOS: não houve alteração significativa nos parâmetros avaliados (IPV, ISG e NIC), em nenhum dos dois sistemas. CONCLUSÃO: a resposta periodontal ao tratamento ortodôntico não apresentou diferenças significativas, para nenhuma das variáveis analisadas, entre os indivíduos tratados com braquetes autoligáveis passivos e braquetes convencionais, os quais receberam instruções quanto à adequada higienização bucal e foram submetidos ao monitoramento das condições periodontais. Abstract in english OBJECTIVE: The aim of the present study was to evaluate, comparatively, the periodontal response during orthodontic treatment performed with self-ligating and conventional brackets. METHODS: Sixteen Caucasian individuals of both sexes, aged between 12 and 16 years old and in permanent dentition wer [...] e selected. Eight individuals were treated with conventional brackets installed on the lower dental arch and self-ligating brackets on the upper arch. Another eight individuals received self-ligating brackets in the lower arch and conventional brackets in the upper arch. The subjects received material and instructions for oral hygiene. Visible plaque index (VPI), gingival bleeding index (GBI) and clinical attachment level (CAL) were evaluated just after installation of orthodontic appliances, and 30, 60 and 180 days later. Mann-Whitney test was used to compare differences between groups (self-ligating and conventional), two-way ANOVA followed by Tukey's test was used to assess CAL at each site of each tooth. Significance level was set at 5%. RESULTS: No significant changes were found with regard to the assessed parameters (VPI, GBI and CAL) in either one of the systems. CONCLUSION: No significant changes were found with regard to the periodontal response to orthodontic treatment for the variables assessed and between subjects receiving passive self-ligating and conventional brackets. All individuals had received oral hygiene instructions and had their periodontal conditions monitored.

  13. Effect of toothbrushing with different manual toothbrushes on the shear bond strength of orthodontic brackets

    Scientific Electronic Library Online (English)

    Guilherme José Pimentel Lopes de, Oliveira; Chaine, Pavone; Maurício Ribeiro, Costa; Rosemary Adriana Chiérici, Marcantonio.

    2010-09-01

    Full Text Available The aim of this study was to evaluate the effect of brushing with a Colgate 360º or Oral B Indicator 35 toothbrush on the shear bond strength of orthodontic brackets bonded to extracted human teeth. The bristle wear and bristle tip morphology were also examined after simulated tooth-brushing. Orthod [...] ontic brackets (Roth-P/1st and 2nd premolar S/D- Slot 0.18") were bonded (Transbond XT®) to the smoothest surface of each of 45 extracted human molar and premolar teeth. Test specimens were randomly divided into three groups: Group 1, control group with no brushing; Group 2, brushing with the Oral B Indicator 35; Group 3, brushing with the Colgate 360º. Samples were adapted to a machine that simulated tooth-brushing. The bond strength of each bracket to each tooth was assessed with a mechanical testing machine. The bristle wear and bristle tip morphology indices were also assessed. Statistically significant differences were defined for p

  14. Microleakage under Orthodontic Metal Brackets Bonded with Three Different Bonding Techniques with/without Thermocycling

    Directory of Open Access Journals (Sweden)

    Berahman Sabzevari

    2013-12-01

    Full Text Available Introduction: The aim of this study was to compare the microleakage of beneath the orthodontic brackets bonded with 3 different bonding techniques and evaluate the effect of thermocycling. Methods: One hundred and twenty premolars were randomly divided into 6 groups, received the following treatment: group 1: 37% phosphoric acid gel+Unite primer+Unite adhesive, group 2: 37% phosphoric acid gel+ Transbond XT primer+Transbond XT adhesive, group 3: Transbond plus Self Etching Primer (TSEP+Transbond XT adhesive. Groups 4, 5, and 6 were similar to groups 1, 2, and 3, respectively. Evaluation of microleakage was done following to thermocycling test. After bonding, the specimens were sealed with nail varnish except for 1 mm around the brackets and then stained with 0.5% basic fuchsine. The specimens were sectioned at buccolingual direction in 2 parallel planes and evaluated under a stereomicroscope to determine the amount of microleakage at bracket-adhesive and adhesive-enamel interfaces from gingival and occlusal margins. Results: Microleakage was observed in all groups, and increased significantly after thermocycling at some interfaces of Unite adhesive group and conventional etching+Transbond XT adhesive group, but the increase was not significant in any interface of TSEP group. With or without thermocycling, TSEP displayed more microleakage than other groups. In most groups, microleakage at gingival margin was significantly higher than occlusal margin. Conclusion: Thermocycling and type of bonding technique significantly affect the amount of microleakage.

  15. Effects of high-speed curing devices on shear bond strength and microleakage of orthodontic brackets.

    Science.gov (United States)

    James, Jeffrey W; Miller, Barbara H; English, Jeryl D; Tadlock, Larry P; Buschang, Peter H

    2003-05-01

    This study evaluated the shear-peel bond strength and mode of bond failure of 3 curing devices (plasma arc light, argon laser, and conventional halogen light) and 2 orthodontic bracket adhesives with different filler contents (Transbond XT and Adhesive Precoated [APC]). Observations of microleakage were also reported. Ninety human adolescent premolars were randomly divided into 6 groups, and standardized brackets were bonded according to the manufacturers' recommendations. The plasma arc light produced significantly (P =.006) higher bond strength than did the halogen light or the argon laser when Transbond was used. When APC was used, the plasma arc light and the halogen light produced similar results, and they both produced significantly (P =.015) higher bond strengths than did the argon laser. Overall, the APC showed substantially less variation in bond strength than did the Transbond. Although all curing methods showed significant microleakage (P curing lights occurred only when APC was used. Microscopic evaluations demonstrated that 95% of the specimens failed for adhesion at the bracket or tooth surface; the argon laser produced the highest adhesive remnant index scores. On the basis of bond strength and microleakage results, the plasma arc light was comparable with or superior to the other curing devices, depending on the adhesive used. PMID:12750676

  16. Comparison of friction produced by two types of orthodontic bracket protectors

    Scientific Electronic Library Online (English)

    Steyner de Lima, Mendonça; Otávio José, Praxedes Neto; Patricia Teixeira de, Oliveira; Patricia Bittencourt Dutra dos, Santos; Fábio Henrique de Sá Leitão, Pinheiro.

    2014-01-01

    Full Text Available INTRODUÇÃO: o aparelho ortodôntico fixo é considerado um fator causador de traumas na mucosa bucal. Com o intuito de controlar o desconforto no tecido mole, diversos ortodontistas recomendam a utilização de uma pequena quantidade de cera utilidade sobre os braquetes como forma de proteção. Esse es [...] tudo teve como objetivo avaliar, in vitro, o atrito gerado por dois tipos de protetores de braquetes (protetor de acetato e de resina - PPA e PRT) durante os estágios iniciais do tratamento ortodôntico. MÉTODOS: o atrito gerado pelos protetores no fio ortodôntico foi avaliado em unidades de teste de modelos experimentais. Esses modelos foram ligados a uma máquina de ensaios mecânicos que simulava o alinhamento do canino superior. A comparação intergrupos foi realizada pela ANOVA, com nível de significância de 5%. RESULTADOS: a fricção apresentada pelo grupo PRT foi estatisticamente maior do que a do grupo controle ao nível de 6mm. Para o atrito máximo, a média do grupo PRT foi estatisticamente maior do que a dos grupos controle e PPA. CONCLUSÃO: o protetor de acetato demonstrou não interferir no atrito entre o fio e a ranhura do braquete ortodôntico. Abstract in english INTRODUCTION: Fixed orthodontic appliances have been regarded as a common causative factor of oral lesions. To manage soft tissue discomfort, most orthodontists recommend using a small amount of utility wax over the brackets in order to alleviate trauma. This in vitro study aimed at evaluating fri [...] ction generated by two types of bracket protectors (customized acetate protector [CAP] and temporary resin protector [TRP]) during the initial stages of orthodontic treatment. METHODS: An experimental model (test unit) was used to assess friction. In order to measure the friction produced in each test, the model was attached to a mechanical testing machine which simulated maxillary canines alignment. Intergroup comparison was carried out by one-way ANOVA with level of significance set at 5%. RESULTS: The friction presented by the TRP group was statistically higher than that of the control group at 6 mm. It was also higher than in the control and CAP groups in terms of maximum friction. CONCLUSION: The customized acetate protector (CAP) demonstrated not to interfere in friction between the wire and the orthodontic bracket slot.

  17. Comparison of shear bond strength of orthodontics brackets on composite resin restorations with different surface treatments

    Scientific Electronic Library Online (English)

    Alexandre Antonio, Ribeiro; Ariane Vicente de, Morais; Daniel Paludo, Brunetto; Antonio Carlos de Oliveira, Ruellas; Monica Tirre Souza de, Araujo.

    2013-08-01

    Full Text Available INTRODUÇÃO: frequentemente, os pacientes ortodônticos apresentam restaurações de resina composta; no entanto, existem poucos estudos que avaliam a melhor forma de colagem ortodôntica nessa situação. OBJETIVO: o objetivo do presente trabalho foi avaliar a força adesiva de braquetes ortodônticos em re [...] staurações resinosas com tratamento de superfície. MÉTODOS: foram utilizados 51 incisivos inferiores bovinos divididos aleatoriamente em três grupos. No grupo controle (GC), os braquetes foram colados em esmalte dentário; nos grupos experimentais com tratamento (GCT) e sem tratamento (GST), os braquetes foram colados em restauração de resina previamente realizada, diferenciando-se pelo tratamento de superfície com broca diamantada. Os dentes foram incluídos em tubos de PVC com resina acrílica autopolimerizável. O ensaio de cisalhamento foi executado em máquina universal de ensaios Emic. Os grupos foram submetidos à ANOVA com pós-teste de Tukey para verificação da diferença estatística entre os grupos (? = 0,05). RESULTADOS: GC (6,62MPa) e GCT (6,82MPa) apresentaram resultados semelhantes, enquanto o GST (5,07MPa) obteve resultados estatisticamente menores (p Abstract in english INTRODUCTION: Orthodontic patients frequently present composite resin restorations, however there are few studies that evaluate the best way for orthodontic bonding in this situation. OBJECTIVE: The objective of this work was to evaluate the bond strength of orthodontic brackets in resin restoration [...] s with surface treatment. METHODS: Fifty one bovine lower incisors were randomly divided into three groups. On the control group (CG) the brackets were bonded to dental enamel; on experimental groups, brackets were bonded to resin restoration with diamond drill treatment (EGT) and with no treatment (EGN). The teeth were placed in PVC tubes with autopolymerized acrylic resin. The shear test was performed in EMIC universal testing machine. The groups were submitted to ANOVA analysis of variance with Tukey post test to verify the statistical difference between groups (? = 0.05). RESULTS: CG (6.62 MPa) and EGT (6.82 MPa) groups presented similar results, while EGN (5.07 MPa) obtained statistically lower results (p

  18. Effect of Fast Curing Lights, Argon Laser, and Plasma Arc on Bond Strengths of Orthodontic Brackets: An In Vitro Study

    Directory of Open Access Journals (Sweden)

    M. Hashem-Hoseini

    2008-12-01

    Full Text Available Objective: Nowadays light-cured composites are used widely by orthodontists to bond brackets. As these composites require 20-40 seconds time per tooth to be light cured, more chair-time in needed compared to self-cured composites. In recent years, the argon laser and plasma arc lights have been introduced in dentistry to reduce this curing time. The purpose of this study was to compare bond strength of brackets bonded with the argon la-ser and plasma arc light with those bonded with the conventional halogen light.Materials and Methods: Fifty-one intact human premolars were randomly divided into three groups of 17 teeth each. Stainless steel twin premolar brackets (018- in Dyna lock, 3M Unitek were bonded to the teeth using one of these curing devices in each group: the halogen unit (Coltolux 75, Switzerland, the argon laser unit (Bo-5, Iran , and the plasma arc unit (Remecure 15, Belgium. The orthodontic adhesive was the same in the three groups (Transbond XT, 3M Unitek. After thermal cycling, the diametral tensilebond strength of specimens was measured using a debonding plier in a Zwick Universal Testing machine (Z/100, Germany.Results: The mean bond strengths was 17.344 MPa (SD=4.567 for halogen 19.172 MPa(SD=6.328 for laser and 19.322 MPa (SD=4.036 for plasma arc groups. No statistically significant difference existed in the mean bond strengths among three groups.Conclusion: Argon laser lights, significantly reducing the curing time of orthodonticbrackets without affecting bond strength, have the potential to be considered as advanta-geous alternatives to conventional halogen light.

  19. A comparative study on time efficiency management of self ligating brackets with conventional ligating brackets on orthodontic subjects in North Karnataka

    OpenAIRE

    Smita B. Patil; M.B. Halkati; Amit Shaikh; Srinivas Ambarkar; Shakeel Galgali

    2014-01-01

    Background: Self-Ligating brackets were originally designed with the intention to reduce the time needed to change wires compared with the use of wire ligatures. However, the advent of elastomeric ligatures meant that this perceived advantage was diminished. Objective: To compare aligning efficiency, rate of retraction and torque expression of Self Ligating bracket (SLB) system with Conventional Pre adjusted Edgewise bracket (CLB) system. Materials and Methods: Twelve patients were selected a...

  20. Analysis of Shear Bond Strength and Morphology of Er:YAG Laser-Recycled Ceramic Orthodontic Brackets

    OpenAIRE

    Han, Ruo-qiao; Yang, Kai; Ji, Ling-fei; Ling, Chen

    2016-01-01

    Objective. The aim of this study was to compare the recycling of deboned ceramic brackets via an Er:YAG laser or via the traditional chairside processing methods of flaming and sandblasting; shear bond strength and morphological changes were evaluated in recycled brackets versus new brackets. Materials and Methods. 3M Clarity Self-Ligating Ceramic Brackets with a microcrystalline base were divided into groups subjected to flaming, sandblasting, or exposure to an Er:YAG laser. New ceramic brac...

  1. Assessment of the dimensions and surface characteristics of orthodontic wires and bracket slots

    Scientific Electronic Library Online (English)

    Gabriel Schmidt, Dolci; Ana Maria, Spohr; Eduardo Rigon, Zimmer; Ernani Menezes, Marchioro.

    2013-04-01

    Full Text Available OBJETIVO: o objetivo desse estudo é avaliar as dimensões e as características superficiais de fios retangulares e slots de braquetes de diferentes marcas comerciais. MÉTODOS: trinta braquetes metálicos (0,022" x 0,028" e 0,022" x 0,030") foram divididos em três grupos: Grupo DYN/3M = Dyna-Lock, 3M/U [...] nitek, aço inoxidável (AI); Grupo STD/MO = Slim Morelli (AI); e Grupo NiFree/MO = Slim Morelli (Ni-Free). Já os fios retangulares (0,019" x 0,025"), de aço inoxidável, foram divididos em 2 grupos: Grupo MO = Morelli; Grupo 3M = 3M/Unitek. As mensurações dos slots dos braquetes e dos fios foram realizadas por dois métodos: (a) microscopia eletrônica de varredura (MEV), e (b) projeção de perfil. A análise da topografia superficial foi realizada qualitativamente, baseada em imagens microscópicas (MEV) e/ou por meio de um rugosímetro. Os resultados quantitativos foram submetidos à análise de variância (ANOVA) com o teste de Tukey (p Abstract in english OBJECTIVE: The purpose of this study was to evaluate the dimensions and surface characteristics of orthodontic wires and bracket slots of different commercial brands. METHODS: Thirty metallic brackets (0.022 x 0.028-in and 0.022 x 0.030-in) were divided in three groups: DYN/3M group = Dyna-Lock, 3M/ [...] Unitek (stainless steel, or SS); STD/MO group = Slim Morelli (SS); and Ni-Free/MO group = Slim Morelli (Ni-Free). The stainless steel wires (0.019 x 0.025in) were divided into two groups: MO group = Morelli; and 3M group = 3M/Unitek. The bracket and wire measurements were done by two methods: (a) Surface Electron Microscopy (SEM), and (b) Profile projection. The surface analysis was done qualitatively, based on SEM images and/or by a rugosimeter. The quantitative results were analyzed by ANOVA with Tukey's test (p

  2. The effect of argon laser irradiation on demineralization resistance of human enamel adjacent to orthodontic brackets: an in vitro study.

    Science.gov (United States)

    Noel, Lloyd; Rebellato, Joe; Sheats, Rose D

    2003-06-01

    Argon lasers, because of their significant timesavings over conventional curing lights, have been investigated for use in bonding orthodontic brackets. They are also being investigated for their ability to confer demineralization resistance on enamel, which is of great interest in orthodontics. A two-part in vitro study on 86 human posterior teeth was conducted to determine the effects of a five-second argon laser exposure on shear bond strength and to evaluate the effects of a five- and 10-second argon laser exposure (250 mW) on demineralization of enamel surrounding orthodontic brackets after exposure to an artificial caries bath. Brackets cured with the argon laser for five seconds yielded mean bond strengths similar to those attained with a 40-second conventional light-cured control (n = 13 per group, 20.4 vs 17.8 MPa). Brackets cured with the argon laser for 10 seconds resulted in significantly lower mean lesion depth when compared with a visible light control (n = 20 per group, 107.8 vs 137.2 microm, P = .038). There were no statistically significant differences in lesion depth between the five-second argon laser and the visible light control groups. Overall, there was a 15% and 22% reduction in lesion depths for the five- and 10-second group, respectively. Poor correlations were found between the clinical appearance of decalcifications and their lesion depth. Argon lasers used for bonding orthodontic brackets would save a significant amount of chair time while possibly conferring demineralization resistance upon the enamel. PMID:12828433

  3. Comparative in vitro study of the shear bond strength of brackets bonded with restorative and orthodontic resins

    Directory of Open Access Journals (Sweden)

    Hassan Isber

    2011-02-01

    Full Text Available The aim of this study was to evaluate the shear bond strength of brackets bonded with different restorative systems and compare it with that afforded by an established orthodontic bonding system. Seventy human bicuspids were used, divided into five different groups with 14 teeth each. Whereas a specific orthodontic bonding resin (TransbondTM XT was used in the control group, the restorative systems Charisma, Tetric Ceram, TPH Spectrum and Z100 were used in the other four groups. Seven days after bonding the brackets to the samples, shear forces were applied under pressure in a universal testing machine. The data collected was evaluated using the ANOVA test and, when a difference was identified, the Tukey test was applied. A 5% level of significance was adopted. The mean results of the shear bond strength tests were as follows: Group 1 (Charisma, 14.98 MPa; Group 2 (Tetric Ceram, 15.16 MPa; Group 3 (TPH, 17.70 MPa; Group 4 (Z100, 13.91 MPa; and Group 5 or control group (TransbondTM XT, 17.15 MPa. No statistically significant difference was found among the groups. It was concluded that all tested resins have sufficient bond strength to be recommended for bonding orthodontic brackets.

  4. Comparative in vitro study of the shear bond strength of brackets bonded with restorative and orthodontic resins

    Scientific Electronic Library Online (English)

    Hassan, Isber; Aldrieli Regina, Ambrosio; Paulo Eduardo Guedes, Carvalho; Karyna Martins do, Valle-Corotti; Danilo Furquim, Siqueira.

    2011-02-01

    Full Text Available The aim of this study was to evaluate the shear bond strength of brackets bonded with different restorative systems and compare it with that afforded by an established orthodontic bonding system. Seventy human bicuspids were used, divided into five different groups with 14 teeth each. Whereas a spec [...] ific orthodontic bonding resin (TransbondTM XT) was used in the control group, the restorative systems Charisma, Tetric Ceram, TPH Spectrum and Z100 were used in the other four groups. Seven days after bonding the brackets to the samples, shear forces were applied under pressure in a universal testing machine. The data collected was evaluated using the ANOVA test and, when a difference was identified, the Tukey test was applied. A 5% level of significance was adopted. The mean results of the shear bond strength tests were as follows: Group 1 (Charisma), 14.98 MPa; Group 2 (Tetric Ceram), 15.16 MPa; Group 3 (TPH), 17.70 MPa; Group 4 (Z100), 13.91 MPa; and Group 5 or control group (TransbondTM XT), 17.15 MPa. No statistically significant difference was found among the groups. It was concluded that all tested resins have sufficient bond strength to be recommended for bonding orthodontic brackets.

  5. Comparative in vitro study of the shear bond strength of brackets bonded with restorative and orthodontic resins.

    Science.gov (United States)

    Isber, Hassan; Ambrosio, Aldrieli Regina; Carvalho, Paulo Eduardo Guedes; Valle-Corotti, Karyna Martins do; Siqueira, Danilo Furquim

    2011-01-01

    The aim of this study was to evaluate the shear bond strength of brackets bonded with different restorative systems and compare it with that afforded by an established orthodontic bonding system. Seventy human bicuspids were used, divided into five different groups with 14 teeth each. Whereas a specific orthodontic bonding resin (Transbond™ XT) was used in the control group, the restorative systems Charisma, Tetric Ceram, TPH Spectrum and Z100 were used in the other four groups. Seven days after bonding the brackets to the samples, shear forces were applied under pressure in a universal testing machine. The data collected was evaluated using the ANOVA test and, when a difference was identified, the Tukey test was applied. A 5% level of significance was adopted. The mean results of the shear bond strength tests were as follows: Group 1 (Charisma), 14.98 MPa; Group 2 (Tetric Ceram), 15.16 MPa; Group 3 (TPH), 17.70 MPa; Group 4 (Z100), 13.91 MPa; and Group 5 or control group (Transbond™ XT), 17.15 MPa. No statistically significant difference was found among the groups. It was concluded that all tested resins have sufficient bond strength to be recommended for bonding orthodontic brackets. PMID:21359451

  6. Microhardness of Enamel Adjacent to Orthodontic Brackets After CO2 Laser Irradiation and Fluoride Application

    Scientific Electronic Library Online (English)

    Leonardo Pucci, Stangler; Fabio Lourenco, Romano; Mariana Umekita, Shirozaki; Rodrigo, Galo; Alessandra Marques Correa, Afonso; Maria Cristina, Borsatto; Mirian Aiko Nakane, Matsumoto.

    2013-09-01

    Full Text Available Este estudo avaliou a eficácia do laser de CO2, associado ou não à aplicação de flúor na microdureza superficial do esmalte dentário adjacente a bráquetes ortodônticos. Foram selecionados 15 molares humanos, dos quais 30 fragmentos de esmalte com 4 mm2 foram obtidos. Os fragmentos foram incluídos em [...] tubos de PVC, contendo resina acrílica, preparados usando lixas d'água e discos de feltro e alumina. Bráquetes ortodônticos cortados ao meio foram colados no esmalte e 3 leituras de microdureza foram realizadas na superfície adjacente: inicial, após desafio cariogênico e final. Os espécimes foram divididos em 3 grupos (n=10): Grupo C - Controle, Grupo L - irradiado com laser de CO2 e Grupo FL - aplicação tópica de flúor e irradiação com laser de CO2. Após leitura inicial, os espécimes foram colocados em solução desmineralizadora por 32 h e a segunda leitura foi realizada para verificar se desmineralização foi uniforme em todos os grupos. Após os tratamentos, os espécimes foram submetidos a ciclagem DES-RE durante 8 dias seguida da leitura da microdureza superficial final. Os dados foram analisdos estatisticamente utilizando ANOVA e o teste de Duncan (?=0,05). Na mensuração final o grupo FL obteve maior valor de microdureza que os grupos C e L (p Abstract in english This study evaluated the effectiveness of carbon dioxide (CO2) laser combined or not with fluoride application on the surface microhardness of enamel adjacent to orthodontic brackets. Fifteen human molars were selected from which 30 enamel fragments measuring 4 mm2 were obtained. The fragments were [...] embedded in PCV tubes with acrylic resin and prepared using water abrasive paper, felt disks and alumina. Orthodontic brackets cut in half were bonded to enamel and 3 microhardness readings were performed on the adjacent surface, as follows: initial, after cariogenic challenge and final. The specimens were divided into the following 3 groups (n=10): Group C: control, Group L: irradiated with CO2 laser, and Group FL: topical fluoride application and CO2 laser irradiation. After initial reading, the specimens were placed in a demineralizing solution for 32 h and the second reading was to verify if demineralization was uniform in all groups. After the treatments, the specimens were submitted to DES-RE cycling for 8 days followed by final surface microhardness reading. The data were analyzed statistically using ANOVA and Duncan test (?=0.05). At the final measurement Group FL obtained higher microhardness value than Groups C and L (p

  7. Diode-pumped solid-state laser for bonding orthodontic brackets: effect of light intensity and light-curing time.

    Science.gov (United States)

    Kim, Young-Oh; Park, Soo-Byung; Son, Woo-Sung; Ko, Ching-Chang; García-Godoy, Franklin; Kim, Hyung-Il; Kwon, Yong Hoon

    2011-09-01

    This study evaluated the shear bond strength (SBS) of orthodontic brackets bonded to teeth using a diode-pumped solid state (DPSS) laser of 473 nm with various light intensity and light-curing settings. For the study, a total of 150 extracted human teeth were divided into ten groups. In the control group, the brackets were bonded to the teeth using a quartz-tungsten-halogen (QTH) light with an intensity of 900 mW/cm(2). In the experimental groups, the brackets were bonded using a DPSS laser with three different light intensities and light-curing times. The same bracket type and adhesive were used in all groups throughout the study. Statistical analysis was performed to compare the SBS, and adhesive remnant index (ARI) among the groups. As results, brackets bonded using the DPSS laser with an intensity of 700 mW/cm(2) for 40 s (totally) showed a slightly higher SBS (12.2 ± 1.8 MPa) than that of those bonded using a QTH light (control; 11.6 ± 1.6 MPa). The SBS values linearly increased with increasing energy density (light intensity × light-curing time) of the DPSS laser (R = 0.95, p light-curing conditions. A comparison of the ARI scores among the groups suggested a similar bracket failure mode. PMID:20532581

  8. Effects of two soft drinks on shear bond strength and adhesive remnant index of orthodontic metal brackets.

    Directory of Open Access Journals (Sweden)

    Soodabeh Sadat Sajadi

    2014-08-01

    Full Text Available Bond failure of brackets during orthodontic treatment is a common problem; which results in treatment interference, increased treatment time and prolonged clinical time for rebonding of failed brackets. The purpose of this study was to evaluate the effects of Coca-Cola and a non-alcoholic beer on the shear bond strength and adhesive remnant index (ARI of orthodontic metal brackets in vitro.Eighty intact human premolars were divided into two experimental groups of Coca-Cola and non-alcoholic beer (Istak, and a control group of artificial saliva. Over a period of thirty days, the test groups were immersed in the respective soft drinks for 5 minutes, twice a day. For the remainder of the time, they were kept in artificial saliva at 37°C. The control group was stored in artificial saliva during the experiment. All samples were subjected to shearing forces using Universal Testing Machine. ARI was determined with a stereomicroscope at ×12 magnification. The data of shear bond strength were statistically analyzed by one-way ANOVA and Tukey's Post-Hoc test and the data of ARI scores were analyzed by Kruskal-Wallis test.No significant difference was observed in ARIs of the three groups (P? 0.552. The shear bond strength of Coke group was significantly lower than that of the two other groups (P? 0.035; but there was no significant difference between the shear bond strength of Istak and the control group (P? 0.999.Coca-Cola decreased the shear bond strength of orthodontic brackets.

  9. Shear bond strength of orthodontic brackets bonded using halogen light and light-emitting diode at different debond times

    Directory of Open Access Journals (Sweden)

    Rebeca Di Nicoló

    2010-03-01

    Full Text Available The aim of this in vitro study was to compare the photoactivation effects of QTH (Quartz-Tungsten-Halogen and LED (Light-Emitting Diode on the SBS (Shear Bond Strength of orthodontic brackets at different debond times. Seventy-two bovine lower incisors were randomly divided into two groups according to the photoactivation system used (QTH or LED. The enamel surfaces were conditioned with Transbond self-etching primer, and APC (Adhesive Pre-Coated brackets were used in all specimens. Group I was cured with QTH for 20 s and Group II with LED for 10 s. Both groups were subdivided according to the different experimental times after bonding (immediately, 24 h and 7 days. The specimens were tested for SBS and the enamel surfaces were analyzed according to the Adhesive Remnant Index (ARI. The statistical analysis included the Tukey's test to evaluate the main effects of photoactivation and debond time on SBS. The Chi-square test was used to compare the ARI values found for each group, and no statistically significant difference was observed. The debond time of 7 days for QTH photoactivation showed statistically greater values of SBS when compared to the immediate and 24 h periods. There was no statistically significant difference between the QTH and LED groups immediately and after the 24 h period. In conclusion, bonding orthodontic brackets with LED photoactivation for 10 s is suggested because it requires a reduced clinical chair time.

  10. Shear bond strength of orthodontic brackets bonded using halogen light and light-emitting diode at different debond times

    Scientific Electronic Library Online (English)

    Rebeca, Di Nicoló; Maria Amelia Maximo de, Araujo; Levy Anderson César, Alves; Rodrigo Othavio de Assunção e, Souza; Daniel Maranha da, Rocha.

    2010-03-01

    Full Text Available The aim of this in vitro study was to compare the photoactivation effects of QTH (Quartz-Tungsten-Halogen) and LED (Light-Emitting Diode) on the SBS (Shear Bond Strength) of orthodontic brackets at different debond times. Seventy-two bovine lower incisors were randomly divided into two groups accord [...] ing to the photoactivation system used (QTH or LED). The enamel surfaces were conditioned with Transbond self-etching primer, and APC (Adhesive Pre-Coated) brackets were used in all specimens. Group I was cured with QTH for 20 s and Group II with LED for 10 s. Both groups were subdivided according to the different experimental times after bonding (immediately, 24 h and 7 days). The specimens were tested for SBS and the enamel surfaces were analyzed according to the Adhesive Remnant Index (ARI). The statistical analysis included the Tukey's test to evaluate the main effects of photoactivation and debond time on SBS. The Chi-square test was used to compare the ARI values found for each group, and no statistically significant difference was observed. The debond time of 7 days for QTH photoactivation showed statistically greater values of SBS when compared to the immediate and 24 h periods. There was no statistically significant difference between the QTH and LED groups immediately and after the 24 h period. In conclusion, bonding orthodontic brackets with LED photoactivation for 10 s is suggested because it requires a reduced clinical chair time.

  11. Biodegradação de braquetes ortodônticos: análise por microscopia eletrônica de varredura Analysis of biodegradation of orthodontic brackets using scanning electron microscopy

    Directory of Open Access Journals (Sweden)

    Luciane Macedo de Menezes

    2010-06-01

    Full Text Available OBJETIVO: analisar, por meio de microscopia eletrônica de varredura, as alterações químicas e estruturais de braquetes metálicos submetidos a um processo de biodegradação in vitro. MÉTODOS: a amostra foi dividida em dois grupos, de acordo com a marca comercial dos acessórios - Grupo A = Dyna-Lock, 3M/Unitek (AISI 303 e Grupo B = LG Edgewise Standard, American Orthodontics (AISI 316L. Os corpos de prova, aparelhos ortodônticos simulados, permaneceram imersos em solução salina (0,05% por um período de 60 dias, a 37ºC, sob agitação. As alterações decorrentes da exposição dos acessórios à solução salina foram investigadas através da observação com microscópio eletrônico de varredura (MEV e análise da composição química (EDX, realizadas antes e após o período de imersão (T0 e T5, respectivamente. RESULTADOS: em T5, houve formação de produtos de corrosão sobre a superfície dos braquetes, especialmente no Grupo A, além disso, houve alterações na composição da liga metálica dos braquetes de ambos os grupos, sendo que, no Grupo A, houve redução dos íons ferro e cromo e, no Grupo B, redução de íons cromo. CONCLUSÃO: os acessórios do Grupo A apresentaram-se menos resistentes à biodegradação in vitro, o que poderia estar associado ao tipo de aço utilizado em sua fabricação (AISI 303.OBJECTIVES: The purpose of this study was to analyze, with the aid of scanning electron microscopy (SEM, the chemical and structural changes in metal brackets subjected to an in vitro biodegradation process. METHODS: The sample was divided into three groups according to brackets commercial brand names, i.e., Group A = Dyna-Lock, 3M/Unitek (AISI 303 and Group B = LG standard edgewise, American Orthodontics (AISI 316L. The specimens were simulated orthodontic appliances, which remained immersed in saline solution (0.05% for a period of 60 days at 37°C under agitation. The changes resulting from exposure of the brackets to the saline solution were investigated by microscopic observation (SEM and chemical composition analysis (EDX, performed before and after the immersion period (T0 and T5, respectively. RESULTS: The results showed, at T5, the formation of products of corrosion on the surface of the brackets, especially in Group A. In addition, there were changes in the composition of the bracket alloy in both groups, whereas in group A there was a reduction in iron and chromium ions, and in Group B a reduction in chromium ions. CONCLUSIONS: The brackets in Group A were less resistant to in vitro biodegradation, which might be associated with the type of steel used by the manufacturer (AISI 303.

  12. A comparative study on time efficiency management of self ligating brackets with conventional ligating brackets on orthodontic subjects in North Karnataka

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    Smita B. Patil

    2014-01-01

    Full Text Available Background: Self-Ligating brackets were originally designed with the intention to reduce the time needed to change wires compared with the use of wire ligatures. However, the advent of elastomeric ligatures meant that this perceived advantage was diminished. Objective: To compare aligning efficiency, rate of retraction and torque expression of Self Ligating bracket (SLB system with Conventional Pre adjusted Edgewise bracket (CLB system. Materials and Methods: Twelve patients were selected and divided into two groups treated with self ligating brackets (SLB, n=6 and conventional ligating brackets (CLB, n=6. The brackets used were 0.22 slot McLaughlin Bennet Trevesi (MBT prescription. Aligning was evaluated with 0.14 Niti followed by 19X25 Heat Activated Ni Ti and then 19X25 stainless steel wires for retraction within 4 months. The rate of retraction was evaluated per month and torque loss after space closure was also estimated. Results: Alignment Efficiency shows significant changes with SLB compared to CLB and also save more than 30% of chair side time during wire adjustments while rate of en masse retraction in SLB shows statistically non significance as compared to CLB system. In case of upper incisor changes when compared between two groups showed less torque loss in SLB than CLB although which was statistically no significant but % difference show SLB have better improvement result than CLB.

  13. Evaluation of different LED light-curing devices for bonding metallic orthodontic brackets

    Scientific Electronic Library Online (English)

    Corina Maia de Souza, Pinto; José Tarcísio Lima, Ferreira; Mírian Aiko Nakane, Matsumoto; Maria Cristina, Borsatto; Raquel Assed Bezerra da, Silva; Fábio Lourenço, Romano.

    Full Text Available O objetivo deste estudo foi avaliar a influência de diferentes aparelhos de luz tipo LED na colagem de bráquetes ortodônticos, através do teste de resistência ao cisalhamento e do Índice de Remanescente do Adesivo (IRA). Coroas de 60 incisivos bovinos receberam a colagem de bráquetes com compósito T [...] ransbond XT. A amostra foi dividida em 4 grupos (n=15) de acordo com os seguintes tipos de fotoativação: HL: controle, luz halógena; OR= Ortholux LED; UL= Ultraled XP e RD= Radii LED. Todas as fotoativações foram realizadas por 40 s. O teste de resistência ao cisalhamento foi realizado em máquina universal de ensaios mecânicos à velocidade de 0,5 mm/min. Os dados foram analisados estatisticamente pelo ANOVA e teste de Tukey. Os escores do IRA foram avaliados em lupa estereoscópica e analisados estatisticamente pelo teste de Kruskal-Wallis. O nível de significância de 5% foi adotado para todas as análises. Os valores médios (MPa) e o desvio-padrão do teste de resistência ao cisalhamento foram 9,82 (3,28), 12,70 (3,35), 9,04 (2,80) e 11,22 (2,36) para o grupo HL, OR, UL e RD, respectivamente. O grupo OR apresentou os maiores valores médios de resistência ao cisalhamento. O grupo HL diferiu significativamente (p0,05). Quanto ao escores do IRA, nenhuma diferença estatística significante foi observada (p>0,05) entre os grupos. Concluiu-se que as unidades de luz Ortholux LED e Radii LED proporcionaram maiores valores de resistência adesiva aos bráquetes. Abstract in english The aim of this study was to assess the influence of different light-emitting diodes (LED) light-curing devices for bonding orthodontic brackets, using the shear bond strength and analysis of adhesive remnant index (ARI). Crowns from 60 bovine incisors received brackets bonded with Transbond XT. Spe [...] cimens were divided into 4 groups (n=15) according to the light-curing procedures: HL = control, halogen light; OR = Ortholux LED; UL = Ultraled XP, and RD = Radii LED. All light-curing procedures were performed for 40 s. Shear bond strength test was evaluated using an universal testing machine at a crosshead speed of 0.5 mm/min. Data were analyzed statistically by ANOVA and Tukey's test. The ARI scores were evaluated with a stereoscopic magnifying glass and analyzed statistically by Kruskal-Wallis test. A significance level of 5% was set for all analyses. Shear bond strength means in MPa and standard deviations were 9.82 (3.28), 12.70 (3.35), 9.04 (2.80) and 11.22 (2.36) for HL, OR, UL and RD, respectively. OR presented the highest shear bond strength mean value. HL differed significantly (p0.05). Regarding the ARI scores, no statistically significant difference was observed (p>0.05) among the groups. In conclusion, Ortholux LED and Radii LED units provided the highest values of bracket adhesive strength.

  14. A comparison of shear bond strengths of orthodontic brackets using various light sources, light guides, and cure times.

    Science.gov (United States)

    Evans, Larry James; Peters, Charles; Flickinger, Craig; Taloumis, Louis; Dunn, William

    2002-05-01

    The objective of this study was to evaluate the effects of different cure times, light sources, and light guides on shear bond strength of orthodontic brackets bonded with Transbond XT (3M Unitek, Monrovia, Calif) to bovine enamel. Specifically, the Power Slot (Reliance Orthodontic Products, Itasca, Ill) light guide was placed on 4 visible light sources to compare shear bond strengths and recommended cure times with the light guides provided with each light source. We randomly divided 240 bovine mandibular incisors into 16 groups; each group consisted of 15 teeth mounted in an acrylic block. Each group of teeth was polymerized with a specific light and light guide combination. Eight groups were sheared after 5 minutes and the remaining 8 groups after 24 hours. After bonding, all brackets were subjected to a shear force with a testing machine. Overall, there was a significant increase in bond strengths of the 24-hour groups compared with the 5-minute shearing groups. However, there were no statistical differences (P =.05) within the 24-hour test groups or the 5-minute test groups. The results of this study indicate that, compared with standard light guides, the Power Slot and the Turbo Tip (Ormco Sybron Dental Specialties, Orange, Calif) light guides can significantly reduce the curing times (10 seconds per bracket; 5 seconds each from mesial and distal) without affecting their shear bond strengths. Therefore, the Power Slot and the Turbo Tip light guides with their collimation of visible light to increase its intensity can be recommended as advantageous alternatives for curing composite resins for orthodontic bonding procedures. PMID:12045769

  15. Evaluation of Self-Etching Adhesive and Er:YAG Laser Conditioning on the Shear Bond Strength of Orthodontic Brackets

    OpenAIRE

    Rosalía Contreras-Bulnes; Scougall-Vilchis, Rogelio J.; Laura E. Rodríguez-Vilchis; Claudia Centeno-Pedraza; Oscar F. Olea-Mejía; María del Carmen Z. Alcántara-Galena

    2013-01-01

    The purpose of this study was to evaluate the shear bond strength, the adhesive remnant index scores, and etch surface of teeth prepared for orthodontic bracket bonding with self-etching primer and Er:YAG laser conditioning. One hundred and twenty bovine incisors were randomly divided into four groups. In Group I (Control), the teeth were conditioned with 35% phosphoric acid for 15 seconds. In Group II the teeth were conditioned with Transbond Plus SEP (5?sec); III and IV were irradiated with...

  16. Comparison of shear bond strength of orthodontic brackets bonded using two different hydrophilic primers: An in vitro study

    Directory of Open Access Journals (Sweden)

    M Kumaraswamy Anand

    2014-01-01

    Full Text Available Context: Salivary control and maintenance of a dry operating field is a prime requisite of orthodontic bonding. Moisture insensitive primer (MIP with a clinical significant bond strength values have a better edge over the conventional hydrophobic bonding systems. Aim: The aim of this study is to investigate the effectiveness of two hydrophilic primers with respect to conventional hydrophobic primer by comparing their shear bond strength (SBS and adhesive-failure locations after contamination with saliva and saliva substitute. Materials and Methods: A total of 150 extracted human premolars were randomly divided into five group s ; Group A (Transbond MIP/saliva substitute, Group B (Opal Primo/saliva substitute, Group C (Transbond MIP/natural saliva, Group D (Opal Primo/natural saliva, control group - Group E (Transbond XT/dry, adhesive-Transbond XT used for all five groups and bonded using stainless steel brackets. Shear forces were applied to the samples with a universal testing machine. SBSs was measured in megapascals. The mode of bond failure was determined using the adhesive remnant index (ARI. Results: The mean SBS produced by Transbond MIP was higher than Opal Primo, which was statistically significant according to one-way analysis of variance. Both the tested groups showed lesser bond strength values than Transbond XT (the control. ARI scores revealed that there was no statistically significant difference in the site of bond failure between study groups. ARI scores were found to be lower for study groups suggesting adhesive failure, compared to higher ARI scores for the control group suggesting cohesive failure. Conclusion: Transbond XT adhesive with Transbond MIP or Opal Primo have clinically acceptable bond strength in wet fields. Opal Primo is a viable option to use as a hydrophilic primer clinically.

  17. Influence of surface treatment on shear bond strength of orthodontic brackets

    Scientific Electronic Library Online (English)

    Ione Helena Vieira Portella, Brunharo; Daniel Jogaib, Fernandes; Mauro Sayão de, Miranda; Flavia, Artese.

    2013-06-01

    Full Text Available INTRODUÇÃO: foram avaliadas as forças de cisalhamento após colagem de braquetes ortodônticos em superfícies resinosas microparticuladas ou micro-híbridas, após diferentes tratamentos de superfície. MÉTODOS: foram utilizados 280 corpos de prova, divididos em grupos de 10 elementos cada, sendo 140 pre [...] enchidos com resina microparticulada Durafill e 140 com resina micro-híbrida Charisma. Os tratamentos de superfície envolveram: ácido fosfórico, ácido fluorídrico, jato de bicarbonato de sódio, jato de óxido de alumínio, pedra e broca. A silanagem foi utilizada em metade dos grupos. O cisalhamento foi realizado com a máquina universal de testes EMIC DL 10000 MF, com célula de 10kg e velocidade de 0,5mm/min. As comparações entre as forças de cisalhamento foram obtidas por meio da análise de variância, e o grau de interação entre os tipos de compósito e o preparo de superfície foram obtidos por meio de uma regressão multivariada. RESULTADOS: as médias e desvios-padrão foram: jato de bicarbonato = 11,27 ± 2,78; broca = 9,26 ± 3,01; pedra = 7,95 ± 3,67; jato de óxido de alumínio = 7,04 ± 3,21; ácido fosfórico = 5,82 ± 1,90; ácido fluorídrico = 4,54 ± 2,87; e sem preparo = 2,75 ± 1,49. Um acréscimo de 1,94MPa foi obtido com o uso do compósito Charisma. A silanagem reduziu em 0,68MPa as médias do compósito Charisma, e aumentou o Durafill com uso do jato de bicarbonato (0,83), broca (0,98) e pedra (0,46). CONCLUSÃO: os preparos com jato de bicarbonato, broca e pedra obtiveram médias de forças apropriadas para colagem. O compósito Charisma apresentou forças de maior intensidade que as da resina Durafill. Abstract in english INTRODUCTION: The shear bond strength of orthodontic brackets bonded to micro-hybrid and micro-particulate resins under different surface treatment methods was assessed. METHODS: Two hundred and eighty test samples were divided into 28 groups (n = 10), where 140 specimens were filled with Durafill m [...] icro-particulate resin and 140 with Charisma composite. In 140 samples, a coupling agent (silane) was applied. The surface treatment methods were: Phosphoric and hydrofluoric acid etching, sodium bicarbonate and aluminum oxide blasting, stone and burs. A Universal Instron Machine was used to apply an occlusal shear force directly to the resin composite bracket surface at a speed of 0.5 mm/min. The means were compared using analysis of variance and multivariate regression to assess the interaction between composites and surface treatment methods. RESULTS: Means and standard deviations for the groups were: Sodium bicarbonate jet 11.27±2.78; burs 9.26±3.01; stone 7.95±3.67; aluminum oxide blasting 7.04±3.21; phosphoric acid 5.82±1.90; hydrofluoric acid 4.54±2.87, and without treatment 2.75±1.49. An increase of 1.94 MPa in shear bond strength was seen in Charisma groups. Silane agent application reduced the Charisma shear bond strength by 0.68 Mpa, but increased Durafill means for bicarbonate blasting (0.83), burs (0.98) and stone drilling (0.46). CONCLUSION: The sodium bicarbonate blasting, burs and stone drilling methods produced adequate shear bond strength and may be suitable for clinical use. The Charisma micro hybrid resin composite showed higher shear bond means than Durafill micro particle composite.

  18. Bacterial adhesion forces and biofilm prevention on orthodontic materials

    OpenAIRE

    Mei, Li,

    2011-01-01

    Bacterial adhesion and biofilm formation cause a variety of serious problems during orthodontic treatment, such as enamel demineralization and soft tissue inflammation. Understanding bacterial adhesion forces to orthodontic materials is an important challenge in both clinical and fundamental orthodontics and allows for the development of preventive measures. The thesis investigated the adhesion forces of oral bacterial strains to orthodontic materials using atomic force microscopy (AFM). This...

  19. Effect of laser-assisted bleaching with Nd:YAG and diode lasers on shear bond strength of orthodontic brackets.

    Science.gov (United States)

    Mirhashemi, Amirhossein; Emadian Razavi, Elham Sadat; Behboodi, Sara; Chiniforush, Nasim

    2015-12-01

    The aim of the present study was to assess the effect of laser-assisted bleaching with neodymium:yttrium-aluminum-garnet (Nd:YAG) and diode lasers on shear bond strength (SBS) of orthodontic brackets. One hundred and four extracted human premolars were randomly divided into four groups: group 1: No bleaching applied (control group); group 2: Teeth bleached with 40 % hydrogen peroxide; group 3: Teeth treated with 30 % hydrogen peroxide activated with Nd:YAG laser (1064 nm, 2.5 W, 25 Hz, pulse duration of 100 ?s, 6 mm distance); and group 4: Teeth treated with 30 % hydrogen peroxide activated with diode laser (810 nm, 1 W, CW, 6 mm distance). Equal numbers of teeth in groups 2, 3, and 4 were bonded at start, 1 h, 24 h, and 1 week after bleaching. A universal testing machine measured the SBS of the samples 24 h after bonding. After bracket debonding, the amount of residual adhesive on the enamel surface was observed under a stereomicroscope to determine the adhesive remnant index (ARI) scores. The SBS in the unbleached group was significantly higher than that in the bleached groups bonded immediately and 1 h after laser-assisted bleaching (P?brackets seems to increase quickly within an hour after laser-assisted bleaching and 24 h after conventional bleaching. Thus, this protocol can be recommended if it is necessary to bond the brackets on the same day of bleaching. PMID:26319247

  20. Comparison of Shear Bond Strength of Orthodontic Brackets Bonded to Enamel Prepared By Er:YAG Laser and Conven-tional Acid-Etching

    Directory of Open Access Journals (Sweden)

    M.H. Hosseini

    2012-01-01

    Full Text Available Introduction: The purpose of this study was to compare shear bond strength (SBS of orthodontic brackets bonded to enamel prepared by Er:YAG laser with two different powers and conventional acid-etching.Materials and Methods: Forty-five human premolars extracted for orthodontic purposes were randomly assigned to three groups based on conditioning method: Group 1- conventional etching with 37% phosphoric acid; Group 2- irradiation with Er:YAG laser at 1 W; and Group 3- irradiation with Er:YAG laser at 1.5 W. Metal brackets were bonded on prepared enamel using a light-cured composite. All groups were subjected to thermocycling process. Then, the specimens mounted in auto-cure acryle and shear bond strength were measured using a universal testing machine with a crosshead speed of 0.5 mm per second. After debonding, the amount of resin remaining on the teeth was determined using the adhesive remnant index (ARI scored 1 to 5. One-way analysis of variance was used to compare shear bond strengths and the Kruskal-Wallis test was performed to evaluate differences in the ARI for different etching types.Results: The mean and standard deviation of conventional acid-etch group, 1W laser group and 1.5W laser group was 3.82 ± 1.16, 6.97 ± 3.64 and 6.93 ± 4.87, respectively.Conclusion: The mean SBS obtained with an Er:YAG laser operated at 1W or 1.5W is approximately similar to that of conventional etching. However, the high variability of values in bond strength of irradiated enamel should be considered to find the appropriate parameters for applying Er:YAG laser as a favorable alternative for surface conditioning.

  1. Comparison of the shear bond strengths of conventional mesh bases and sandblasted orthodontic bracket bases

    Scientific Electronic Library Online (English)

    Isabel Cristina Prado Torres, Lugato; Lilian Maria Brisque, Pignatta; Flávia de Moraes, Arantes; Eduardo César Almada, Santos.

    2009-12-01

    Full Text Available This study aimed to compare in vitro the shear bond strength between metallic brackets (Abzil) with conventional mesh bases and metallic brackets with bases industrially sandblasted with aluminum oxide using three adhesive systems, in order to assess the influence of sandblasting on adhesiveness and [...] to compare 3 different bonding systems. Two hundred and forty bovine incisors were used and randomly divided into 6 groups (40 teeth in each group), according to the bracket base and to the bonding system. The brackets were direct-bonded in bovine teeth with 3 adhesive systems: System A - conventional TransbondTM XT (3M - Unitek); System B - TransbondTM Plus Self Etching Primer + TransbondTM XT (3M - Unitek) and System C - Fuji ORTHO LC resin-reinforced glass ionomer cement in capsules (GC Corp.). Shear bond strength tests were performed 24 hours after bonding, in a DL-3000 universal testing machine (EMIC), using a load cell of 200 kgf and a speed of 1 mm/min. The results were submitted to statistical analysis and showed no significant difference between conventional and sandblasted bracket bases. However, comparison between the bonding systems presented significantly different results. System A (14.92 MPa) and system C (13.24 MPa) presented statistically greater shear bond strength when compared to system B (10.66 MPa). There was no statistically significant difference between system A and system C.

  2. Evaluation of Self-Etching Adhesive and Er:YAG Laser Conditioning on the Shear Bond Strength of Orthodontic Brackets

    Science.gov (United States)

    Contreras-Bulnes, Rosalía; Scougall-Vilchis, Rogelio J.; Rodríguez-Vilchis, Laura E.; Centeno-Pedraza, Claudia; Olea-Mejía, Oscar F.; Alcántara-Galena, María del Carmen Z.

    2013-01-01

    The purpose of this study was to evaluate the shear bond strength, the adhesive remnant index scores, and etch surface of teeth prepared for orthodontic bracket bonding with self-etching primer and Er:YAG laser conditioning. One hundred and twenty bovine incisors were randomly divided into four groups. In Group I (Control), the teeth were conditioned with 35% phosphoric acid for 15 seconds. In Group II the teeth were conditioned with Transbond Plus SEP (5?sec); III and IV were irradiated with the Er:YAG 150?mJ (11.0?J/cm2), 150?mJ (19.1?J/cm2), respectively, at 7–12?Hz with water spray. After surface preparation, upper central incisor stainless steel brackets were bonded with Transbond Plus Color Change Adhesive. The teeth were stored in water at 37°C for 24 hours and shear bond strengths were measured, and adhesive remnant index (ARI) was determined. The conditioned surface was observed under a scanning electron microscope. One-way ANOVA and chi-square test were used. Group I showed the significantly highest values of bond strength with a mean value of 8.2 megapascals (MPa). The lesser amount of adhesive remnant was found in Group III. The results of this study suggest that Er:YAG laser irradiation could not be an option for enamel conditioning. PMID:24228014

  3. Avaliação da superfície da porcelana após a descolagem de braquetes ortodônticos Porcelain surface evaluation after debonding of orthodontic brackets

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    André Moreira Mattos

    2006-10-01

    Full Text Available OBJETIVO: o objetivo deste trabalho foi avaliar a influência do tempo de condicionamento ácido em superfície de porcelana e o estado desta após a descolagem de braquetes ortodônticos. METODOLOGIA: foram utilizadas 20 amostras de porcelana feldspática para esmalte (Duceram-LFC divididas em 2 grupos de acordo com o tempo de condicionamento com ácido fluorídico 10% (15 segundos e 1 minuto. Após o ataque ácido, foi aplicado silano (3M Scotchbond, adesivo resinoso (Optibond Solo Plus e resina (Fill Magic nestas superfícies. A descolagem foi realizada através de força de cisalhamento numa máquina universal de ensaios (DL 500 - EMIC calibrada com velocidade fixa de 0,5mm/minuto. O índice do adesivo remanescente (ARI nas superfícies cerâmicas e o estado destas após a remoção dos braquetes foram avaliados através de fotos digitais. RESULTADOS: no grupo 15 segundos, a força de adesão média foi de 3,63MPa, significantemente inferior à do grupo 1 minuto, que foi de 7,18MPa (pAIM: the aim of this study was to evaluate the influence of acid conditioning time in porcelain surface and its characteristics after debonding of orthodontic brackets. METHODS: twenty samples of feldspathic porcelain for enamel (Duceram-LFC were divided in 2 groups according with the amount of time of acid conditioning with hydrofluoric acid 10% (15 seconds and 1 minute. After acid etching, it was applied silane (3M Scotchbond, adhesive (Optibond Solo Plus and resin (Fill Magic in these surfaces. The debonding was done with shear strength through a universal testing machine (DL 500 - EMIC calibrated with a fixed speed of 0.5mm/minute. The adhesive remnant index (ARI in the porcelain surfaces and their characteristics after removal of the brackets were evaluated through digital pictures. RESULTS: in the 15 seconds group, the mean bond strength was 3.63Mpa, significantly lower than the 1 minute group, that was 7.18Mpa (p<0.0001. All fractures during debonding were cohesive in the composite resin layer (70% or bond between the bracket and the resin (30%. In relation to the ARI analysis, the Chi-square test showed no statistically significant difference between both groups. CONCLUSION: conditioning with hydrofluoric acid 10% for 1 minute, followed by the application of silane, adhesive and resin was considered the best porcelain preparation method before orthodontic bonding.

  4. Avaliação in vitro da liberação de níquel por braquetes metálicos / In vitro nickel release from metallic orthodontic brackets

    Scientific Electronic Library Online (English)

    Marina Lara, Sória; Luciane, Menezes; Berenice, Dedavid; Marçal, Pires; Susana, Rizzatto; Luiz Cesar da, Costa Filho.

    2005-06-01

    Full Text Available O aço inoxidável austenítico é utilizado para confecção de dispositivos ortodônticos e contém cerca de 8-10% de níquel em sua composição, metal este responsável por reações alérgicas de hipersensibilidade. Acredita-se que a liberação de níquel dos dispositivos metálicos pode provocar dermatites de c [...] ontato em pacientes suscetíveis. Este estudo laboratorial avaliou a influência de três variáveis na liberação de níquel: 1) o tipo de liga do braquete; 2) o tipo de solução de imersão e 3) o esforço mecânico nas canaletas dos braquetes de aço inoxidável austenítico. Foram avaliados seis grupos experimentais e dois grupos controles. As amostras foram imersas em tubos de ensaio contendo saliva artificial ou solução salina, sendo mantidas sob agitação e temperatura constante (37ºC). A quantidade de níquel presente nas soluções foi avaliada com espectrofotômetro de absorção atômica (Varian - Spectra A55) em dois momentos: após uma semana e após duas semanas. Os resultados revelaram que os braquetes de aço inoxidável com baixo teor de níquel apresentaram menor liberação deste elemento. Foi possível constatar que o tipo de solução alterou o padrão de liberação de níquel pelos dispositivos avaliados. O esforço mecânico aplicado sobre os braquetes de aço inoxidável austenítico não alterou a quantidade de níquel liberada. Abstract in english Austenitic stainless steel is frequently used to fabricate orthodontic appliances, which contains 8-10% of nickel. Such metal is responsible for hypersensitivity allergic reactions. Thus, nickel release of orthodontic appliances may be responsible for contact dermatitis in sensitive patients. This s [...] tudy assessed the influence of three variables in nickel release of metal brackets: 1) type of metal alloy; 2) type of solution used for immersion; and 3) mechanical stress. Six experimental and two control groups were assessed. The specimens were immersed in saline solution or artificial saliva, maintained in constant agitation in controlled temperature environment (37ºC). Nickel present in solutions was measured with atomic spectroscopy (Varian-Spectra A55) in two moments: after one and after two weeks. The results showed that brackets made of low nickel contend alloy released less nickel than standard ones. It was possible to notice that the type of solution alters the pattern of nickel release. Mechanical stress applied in the slots of standard brackets did not influence nickel release.

  5. Influência da secção transversa de fios ortodônticos na fricção superficial de braquetes autoligados / Influence of the cross-section of orthodontic wires on the surface friction of self-ligating brackets

    Scientific Electronic Library Online (English)

    Roberta, Buzzoni; Carlos N., Elias; Daniel J., Fernandes; José Augusto M., Miguel.

    2011-08-01

    Full Text Available OBJETIVO: o objetivo do presente trabalho foi determinar a força de atrito estático entre braquetes de aço inoxidável autoligados com sistema de fechamento resiliente e fios ortodônticos redondos e retangulares do mesmo material. MÉTODOS: empregaram-se 30 braquetes referentes aos caninos superiores [...] divididos em 6 grupos formados por braquetes autoligados Smartclip, In-Ovation R e convencionais Gemini amarrados com ligaduras elásticas. A hipótese testada neste trabalho foi quanto à possibilidade dos braquetes autoligados ativos serem suscetíveis à elevação da força de atrito com o aumento e alteração da secção transversal dos fios ortodônticos. Os ensaios foram realizados com tração de 30s em fios de aço inoxidável 0,020" e 0,019"X0,025" na máquina de ensaios Emic DL 10000, com uma célula de carga de 20 newtons. Cada conjunto braquete/fio foi responsável pela geração de quatro corpos de prova, totalizando 120 leituras. As comparações entre as médias foram realizadas através da Análise de Variância (one way ANOVA) com correções pelo coeficiente de Bonferroni. RESULTADOS E CONCLUSÃO: os braquetes autoligados apresentaram maior força de atrito do que os braquetes convencionais amarrados com ligaduras elásticas. O grupo Smartclip foi o mais efetivo no controle do atrito (p Abstract in english OBJECTIVES: The purpose of this study was to assess the surface friction produced by self-ligating stainless steel brackets equipped with a resilient closure system and compare the friction generated during traction of round and rectangular orthodontic wires made from the same material. METHODS: Thi [...] rty maxillary canine brackets were divided into six groups comprising SmartClip and In-Ovation R self-ligating brackets, and conventional Gemini brackets tied with elastomeric ligatures. This investigation tested the hypothesis that self-ligating brackets are susceptible to increases in friction that are commensurate with increases and changes in the cross-section of orthodontic wires. Traction was performed with the aid of thirty segments of 0.020" and 0.019" x 0.025" stainless steel wires in an EMIC DL 10000 testing machine with a 2N load cell. Each set of bracket/wire generated four samples, totaling 120 readings. Comparisons between means were performed using analysis of variance (one way ANOVA) corrected with the Bonferroni coefficient. RESULTS AND CONCLUSION: The self-ligating brackets exhibited lower friction than conventional brackets tied with elastomeric ligatures. The SmartClip group was the most effective in controlling friction (p

  6. Are torque values of preadjusted brackets precise?

    Scientific Electronic Library Online (English)

    Alessandra Motta, Streva; Flávio Augusto, Cotrim-Ferreira; Daniela Gamba, Garib; Paulo Eduardo Guedes, Carvalho.

    2011-08-01

    Full Text Available OBJECTIVE: The aim of the present study was to verify the torque precision of metallic brackets with MBT prescription using the canine brackets as the representative sample of six commercial brands. MATERIAL AND METHODS: Twenty maxillary and 20 mandibular canine brackets of one of the following comm [...] ercial brands were selected: 3M Unitek, Abzil, American Orthodontics, TP Orthodontics, Morelli and Ortho Organizers. The torque angle, established by reference points and lines, was measured by an operator using an optical microscope coupled to a computer. The values were compared to those established by the MBT prescription. RESULTS: The results showed that for the maxillary canine brackets, only the Morelli torque (-3.33º) presented statistically significant difference from the proposed values (-7º). For the mandibular canines, American Orthodontics (-6.34º) and Ortho Organizers (-6.25º) presented statistically significant differences from the standards (-6º). Comparing the brands, Morelli presented statistically significant differences in comparison with all the other brands for maxillary canine brackets. For the mandibular canine brackets, there was no statistically significant difference between the brands. CONCLUSIONS: There are significant variations in torque values of some of the brackets assessed, which would clinically compromise the buccolingual positioning of the tooth at the end of orthodontic treatment.

  7. Are torque values of preadjusted brackets precise?

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    Alessandra Motta Streva

    2011-08-01

    Full Text Available OBJECTIVE: The aim of the present study was to verify the torque precision of metallic brackets with MBT prescription using the canine brackets as the representative sample of six commercial brands. MATERIAL AND METHODS: Twenty maxillary and 20 mandibular canine brackets of one of the following commercial brands were selected: 3M Unitek, Abzil, American Orthodontics, TP Orthodontics, Morelli and Ortho Organizers. The torque angle, established by reference points and lines, was measured by an operator using an optical microscope coupled to a computer. The values were compared to those established by the MBT prescription. RESULTS: The results showed that for the maxillary canine brackets, only the Morelli torque (-3.33º presented statistically significant difference from the proposed values (-7º. For the mandibular canines, American Orthodontics (-6.34º and Ortho Organizers (-6.25º presented statistically significant differences from the standards (-6º. Comparing the brands, Morelli presented statistically significant differences in comparison with all the other brands for maxillary canine brackets. For the mandibular canine brackets, there was no statistically significant difference between the brands. CONCLUSIONS: There are significant variations in torque values of some of the brackets assessed, which would clinically compromise the buccolingual positioning of the tooth at the end of orthodontic treatment.

  8. Corrosion Inhibitory Ability of Ocimum Sanctum Linn (Tulsi Rinse on Ion Release from Orthodontic Brack-ets in Some Mouthwashes: An Invitro Study

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    Roopal Patel, Sheron Bhanat, Dolly Patel, Bhadra Shah

    2014-01-01

    Full Text Available Introduction: In the oral environment, orthodontic appliances are exposed to potentially damaging physical and chemical agents which may cause metallic corrosion. Corrosion will occur continuously in mouth, due to release of irons with abrasion by food, liquids etc. The purpose of this study was to measure the amount of metal ion release from orthodontic brackets when kept in different mouthwashes and effect of tulsi rinse on ion release when combined with different mouthwashes. Methods: Three hundred and twenty stainless steel brackets (0.022” were divided randomly into 8 equal groups and immersed in Mouthwash-A and, Mouthwash-B and mouthwash-C and distilled deionized water. These mouthwashes and distilled deionized water were all sepa-rately mixed with tulsi rinse and incubated at 37°C for 45 days. Nickel, Chromium, iron, copper and manganese released from the orthodontic brackets were measured with an inductively coupled plasma spectrometer. Results: Ion release in deionized water was higher (p<0.05 than in the 3 mouthwashes. Higher ion release was also found with Mouthwash-B compared with other 2 mouthwashes. There is no difference (p>0.05 in nickel, chromium, iron and copper ion release in the Mouthwash-A and Mouthwash-C. Tulsi rinse showed significant reduction (p<0.05 in all ion release in 3 mouthwashes used along with distilled deionzed water group. Conclusion: If ion release is concerned, Mouthwash-C mixed with tulsi rinse might be better option than Mouthwash-A as well as Mouthwash-B for orthodontic patients with stainless steel brackets.

  9. Properties of Composite Materials Used for Bracket Bonding

    Scientific Electronic Library Online (English)

    Ana Caroline Silva, Gama; Andre Guaraci de Vito, Moraes; Lilyan Cardoso, Yamasaki; Alessandro Dourado, Loguercio; Ceci Nunes, Carvalho; Jose, Bauer.

    2013-06-01

    Full Text Available O objetivo desse estudo foi avaliar a resistência ao cisalhamento no esmalte, resistência flexural, módulo flexural, tensão de contração de polimerização de duas resinas flow e uma resina ortodôntica. Os bráquetes ortodônticos foram colados em 45 pré-molares humanos e divididos: Transbond XT, Filtek [...] Z-350 flow, Opallis flow e testado para resistência ao cisalhamento (n=15). Para a resistência e módulo flexural espécimes foram confeccionados e testados sob flexão. Para o teste de tensão de contração de polimerização, espécimes cilíndricos foram confeccionados e monitorados com um extensômetro (Instron). Os dados foram submetidos aos testes ANOVA a um critério e Tukey (?=0,05) para contraste de média. (n=15). A resistência de união das resinas flow foram significantemente menos que o da resina ortodôntica (p>0,05). A resistência flexural não demonstrou diferença significante entre os grupos testados (p>0,05). O módulo flexural da resina ortodôntica foi significantemente maior que o grupo das resinas flow (p Abstract in english The purpose of this study was to evaluate in vitro the shear bond strength to enamel, flexural strength, flexural modulus, and contraction stress of one orthodontic composite and two flowable composites. Orthodontic brackets were bonded to 45 human maxillary premolars with the composites Transbond X [...] T, Filtek Z-350 flow and Opallis flow and tested for shear bond strength. For measurement of flexural strength and flexural modulus, specimens were fabricated and tested under flexion. For the contraction stress test, cylindrical specimens were tested and an extensometer determined the height of the specimens. The data were subjected to one-way ANOVA and Tukey's test (?=0.05). The shear bond strength values were significantly lower (p0.05) while the flexural modulus was significantly higher (p

  10. Streptococcus mutans counts in plaque adjacent to orthodontic brackets bonded with resin-modified glass ionomer cement or resin-based composite

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    Solange Machado Mota

    2008-03-01

    Full Text Available This study investigated the number of Streptococcus mutans CFU (colony forming units in the saliva and plaque adjacent to orthodontic brackets bonded with a glass ionomer cement - GIC (Fuji Ortho or a resin-based composite - RC (Concise. Twenty male and female patients, aged 12 to 20 years, participated in the study. Saliva was collected before and after placement of appliances. Plaque was collected from areas adjacent to brackets and saliva was again collected on the 15th, 30th, and 45th day after placement. On the 30th day, 0.4% stannous fluoride gel was applied for 4 minutes. No significant modification in the number of Streptococcus mutans CFU in saliva was observed after placement of the fixed orthodontic appliances. On the 15th day, the percentage of Streptococcus mutans CFU in plaque was statistically lower in sites adjacent to GIC-bonded brackets (mean = 0.365 than in those adjacent to RC-bonded brackets (mean = 0.935. No evidence was found of a contribution of GIC to the reduction of CFU in plaque after the 15th day. Topical application of stannous fluoride gel on the 30th day reduced the number of CFU in saliva, but not in plaque. This study suggests that the antimicrobial activity of GIC occurs only in the initial phase and is not responsible for a long-term anticariogenic property.

  11. Effect of Ascorbic Acid on Shear Bond Strength of Orthodontic Brackets Bonded with Resin-modified Glass-ionomer Cement to Bleached Teeth

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    Behnam Khosravanifard

    2012-04-01

    Full Text Available Background and aims. Bleaching can considerably reduce shear bond strength (SBS of orthodontic brackets bonded with composite adhesives. Application of antioxidants is a method to reverse the negative effect of bleaching on compositeto-enamel bond. However, the efficacy of antioxidants in increasing the SBS of brackets bonded using resin-modified glassionomer cement (RMGIC has not been studied, which was the aim of this study. Materials and methods. Fifty freshly extracted human maxillary first premolars were bleached with 35% hydrogen peroxide (Pola Office Bleaching, SDI. Sodium ascorbate 10% was applied to the experimental specimens (n=25. All the specimens were etched with 37% phosphoric acid (Ivoclar/Vivadent and bonded using RMGIC (Fuji Ortho LC, GC. The specimens were subjected to incubation (37°C, 24h and thermocycling (1000 cycles, 5-55°C, dwell time = 1 min. The SBS was measured at 0.5 mm/min debonding crosshead speed. The adhesive remnant index (ARI was scored under ×10 magnification. Data were analyzed using Mann-Whitney U test, one- and independent-samples t-test, and Fisher’s exact test (?=0.05. Results. The mean SBS of experimental and control groups were 11.97 ± 4.49 and 7.7 ± 3.19 MPa, respectively. The difference was statistically significant (P=0.000 by t-test. SBS of both control (P=0.014 and experimental (P=0.000 groups were significantly higher than the minimum acceptable SBS of 6 MPa, according to one-sample t-test. Conclusion. Application of ascorbic acid can guarantee a strong bond when RMGIC is to be used. However, RMGIC might tolerate the negative effect of bleaching with minimum SA treatments (or perhaps without treatments, which deserves further studies.

  12. Conforto e fonação com a nova geração de bráquetes ortodônticos linguais individualizados Comfort and phonation with new generation of individualized lingual orthodontics brackets

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    Adriano Marotta Araújo

    2009-12-01

    Full Text Available TEMA: recentemente o número de pacientes desejando um tratamento ortodôntico e estético ao mesmo tempo aumentou consideravelmente. A técnica lingual oferece a opção mais estética de tratamento ortodôntico, pois os bráquetes ficam invisíveis colados na superfície lingual dos dentes e os lábios não ficam protuberantes. Apesar da grande vantagem estética, essa terapia possui desvantagens como restrição no conforto oral, na fala, na higiene, irritações na língua, restrição no espaço da língua e dificuldades na alimentação. Para amenizar essas desvantagens uma nova geração de bráquetes linguais otimizados ao máximo através da individualização das bases dos bráquetes, da posição de colagem e dos fios utilizados no tratamento ortodôntico foi desenvolvida recentemente. OBJETIVO: realizar uma revisão sistemática da literatura para verificar a adaptação do paciente a diferentes dispositivos ortodônticos linguais e a influência desses dispositivos no conforto e na fala, principalmente. CONCLUSÃO: atualmente a literatura suporta que os bráquetes linguais de última geração individualizados por computador proporcionam maior conforto e facilidade na fonação quando comparados aos bráquetes tradicionais da técnica lingual. No entanto, o sucesso na terapia requer orientações detalhadas sobre o potencial de restrição do conforto oral, articulação de palavras, mastigação e higiene oral, independente do sistema de bráquetes a ser utilizado.BACKGROUND: the number of patients desiring an orthodontic and esthetic treatment at the same time recently increased considerably. The lingual technique offers the most aesthetic orthodontic treatment option because the brackets are invisible on the lingual surface of the teeth and the lips are not protruding. Despite the aesthetic advantage, this therapy has disadvantages such as restriction in oral comfort, in speech, in oral hygiene, injuries in the tongue and difficulties for eating. To improve these disadvantages, a new generation of lingual brackets optimized to the maximum through the individualization of the bases, the position of the bracket and wires used in orthodontic treatment have been recently developed. PURPOSE: to make a systematically review of literature to verify the patient's adaptation to different lingual orthodontic devices and the influence of these appliance in comfort and speech, as well. CONCLUSION: the literature currently supports that the latest generation of lingual individualized brackets provides greater comfort and speech easiness when compared to the traditional lingual technique brackets. However, success in therapy requires detailed guidelines on the potential for restriction of the oral comfort, word articulation, chewing and oral hygiene, regardless of the bracket system to be used.

  13. Influence of bleaching and desensitizing gel on bond strength of orthodontic brackets

    Scientific Electronic Library Online (English)

    Fernanda Alves Rodrigues, Britto; Adriana Simoni, Lucato; Heloisa Cristina, Valdrighi; Sílvia Amélia Scudeler, Vedovello.

    2015-04-01

    Full Text Available OBJETIVO: o objetivo do presente estudo foi avaliar, in vitro, a influência do gel clareador e da utilização de dessensibilizante na resistência adesiva de braquetes cerâmicos colados ao esmalte bovino. MÉTODOS: cem incisivos bovinos foram aleatoriamente divididos em cinco grupos (n = 20). Grupo 1, [...] sem clareamento (controle); Grupo 2, clareamento com peróxido de hidrogênio a 35%; Grupo 3, clareamento com peróxido de hidrogênio a 35%, sendo três aplicações de 15 minutos cada, e aplicação do dessensibilizante por 10 minutos; Grupo 4, clareamento com peróxido de hidrogênio a 35% durante 40 minutos; Grupo 5, clareamento com peróxido de hidrogênio a 35% durante 40 minutos e aplicação do dessensibilizante durante 10 minutos. Os braquetes foram colados sete dias após o clareamento e submetidos ao teste de resistência ao cisalhamento após 24 horas, a uma velocidade de compressão de 1mm/minuto. Após a fratura, avaliava-se o braquete, com lupa estereoscópica, com magnificação de 40x, e o Índice de Remanescente Adesivo (IRA). Os dados de resistência ao cisalhamento (MPa) foram submetidos à análise de variância e ao teste de Tukey, com nível de significância de 5%. RESULTADOS: os resultados mostraram que as amostras do Grupo 5 apresentaram resistência de união significativamente superior à dos grupos 1, 2 e 4, mas sem diferença do Grupo 3. Não houve diferença significativa entre a resistência de união dos demais grupos. O Índice de Remanescente Adesivo mostrou predominância do escore 3, ou seja, toda resina permaneceu aderida ao esmalte, para todos os grupos. CONCLUSÃO: pôde-se concluir que o clareamento com peróxido de hidrogênio a 35%, com cálcio associado à aplicação do dessensibilizante, produziu maior resistência dos braquetes ao esmalte bovino. Abstract in english OBJECTIVE: The objective of this study was to assess, in vitro, the influence of bleaching gel and the use of desensitizing agent over bond strength of ceramic brackets bonded to bovine enamel. METHODS: One hundred bovine incisors were selected and randomly divided into five groups (n = 20): Group [...] 1, control group (without bleaching); Group 2, bleached with 35% hydrogen peroxide; Group 3, bleached with 35% hydrogen peroxide (three applications, 15 minutes each) and desensitizing agent applied for 10 minutes; Group 4, bleached with 35% hydrogen peroxide for 40 minutes; Group 5, bleached with 35% hydrogen peroxide for 40 minutes with desensitizing agent applied for 10 minutes. Brackets were bonded 7 days after bleaching and submitted to shear bond strength test after 24 hours at a compression rate of 1 mm/minute. After fracture, the adhesive remnant index (ARI) was assessed under stereoscopic at 40 x magnification. Shear strength data (MPa) were submitted to one-way ANOVA and Tukey's test with significance level set at 5%. RESULTS: Group 5 (29.33 MPa) showed significantly higher bond strength than Group 1 (19.19 MPa), Group 2 (20.59 MPa) and Group 4 (23.25 MPa), but with no difference in comparison to Group 3. There was no significant difference among the other groups. The adhesive remnant index showed predominance of score 3, that is, all resin remained adhered to enamel for all groups. CONCLUSION: Bleaching with 35% hydrogen peroxide with calcium associated with desensitizing agent application produced higher bond strength values of brackets bonded to bovine enamel.

  14. In vitro corrosion of metallic orthodontic brackets: influence of artificial saliva with and without fluorides

    Scientific Electronic Library Online (English)

    Mônica Pereira, Saporeti; Enio Tonani, Mazzieiro; Wisley Falcco, Sales.

    2012-12-01

    Full Text Available OBJETIVO: este estudo in vitro verificou a resistência à corrosão de braquetes metálicos, avaliando-se os aspectos superficiais em microscopia eletrônica de varredura (MEV) e os componentes residuais formados. MÉTODOS: a amostra consistiu de 17 conjuntos de braquetes de quatro diferentes ligas metál [...] icas: titânio, cobalto-cromo, aço inoxidável com baixa concentração de níquel e com cobertura de nitreto de titânio (TiN). Doze conjuntos foram submetidos à corrosão por imersão em 50ml de saliva artificial (pH 6,5) e 4 em saliva (pH 6,5) contendo flúor (2g/l), todos sob temperatura de 37ºC, e analisados após 7, 9 e 11 semanas. Uma montagem foi mantida como controle. As análises consistiram na avaliação qualitativa da corrosão por meio das imagens obtidas no MEV, na avaliação semiquantitativa da composição química dos resíduos superficiais por meio de MEV-EDS e da quantidade de íons liberados nas salivas na avaliação da espectrofotometria de absorção atômica. RESULTADOS: os resultados demonstraram que os braquetes com liga de titânio puro e os de aço com baixa concentração de níquel foram superiores em relação à resistência à corrosão. A liga de cobalto-cromo foi a que apresentou maior corrosão. Na presença do flúor, observaram-se maiores alterações em todas as ligas, com destaque para as de aço cobertos com TiN e as de cobalto-cromo. CONCLUSÃO: apesar de se observar a corrosão no MEV, a espectrofotometria mostrou baixo desprendimento de íons nas salivas artificiais, porém a presença do flúor interferiu negativamente na resistência à corrosão. Abstract in english OBJECTIVE: This in vitro study verified the resistance to corrosion of metallic brackets, evaluating the superficial aspects in scanning electron microscopy (SEM) and the residual components. METHODS: The sample consisted of 17 sets of brackets of four different metallic alloys: Titanium, Cobalt-Chr [...] omium, Stainless steel with low nickel concentration and with titanium nitride coating (NiTi). Twelve sets were submitted to corrosion by immersion in 50 ml of artificial saliva (pH 6.5) and four in saliva (pH 6.5) containing fluoride (2 g/l), all at a temperature of 37 ºC and analyzed after 7, 9 and 11 weeks. One was kept as control set. The analysis consisted in qualitative evaluation of the corrosion by the images obtained on the SEM, in semi-quantitative evaluation of chemical composition of the surface residue by SEM-EDS and the amount of ions released in saliva on evaluation of atomic absorption spectrophotometry. RESULTS: The results showed that the pure titanium brackets and the ones with low nickel concentration were superior regarding resistance to corrosion. The cobalt-chromium alloy showed the greatest corrosion. In the presence of fluoride, it was observed greater variation in all alloys, especially in the ones of NiTi coated steel and the ones of cobalt-chromium. CONCLUSION: Although observed corrosion on the SEM, the spectrophotometry showed low ions release in the artificial saliva, however, the presence of fluoride negatively affected the corrosion resistance.

  15. An overview of orthodontic material degradation in oral cavity

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    Chaturvedi T

    2010-01-01

    Full Text Available Various types of metallic orthodontic appliances are used in the management of malocclusion. These appliances are placed in oral environnent under many stresses and variations such as masticatory forces, appliance loading, temperature fluctuations, varieties of ingested food and saliva. These metals undergo electrochemical reactions with the oral environment resulting in dissolution or formation of chemical compounds. Various microorganisms and many aggressive ions containing oral environment can cause material degradation (corrosion and its associated problems during long time exposure. Orthodontic alloys must have excellent corrosion resistance to the oral environment, which is highly important for biocompatibility as well as for orthodontic appliance durability. This article reviews various aspects of corrosion (surface degradation of orthodontic alloys. It explores the emerging research strategies for probing the biocompatibility of materials. During orthodontic treatment, use of nickel free, better corrosion resistance alloys and less use of fluoride containing toothpaste or gel is expected.

  16. Effect of fluoridated milk on enamel demineralization adjacent to fixed orthodontic appliances

    DEFF Research Database (Denmark)

    Sköld-Larsson, Kerstin; Sollenius, Ola; Karlsson, Lena; Petersson, Lars G; Twetman, Svante

    2012-01-01

    Abstract Objective. To investigate the effect of daily intake of fluoridated milk on enamel demineralization adjacent to fixed orthodontic brackets assessed with quantitative light-induced fluorescence (QLF). Materials and methods. Sixty-four healthy adolescents (13-18 years) undergoing orthodontic....... Conclusion. Daily intake of fluoridated milk may aid remineralization of white spot lesions adjacent to fixed orthodontic appliances....

  17. Effectiveness of Mouth Washes on Streptococci in Plaque around Orthodontic Appliances

    OpenAIRE

    Mohammad Hosein Kalantar Motamedi; Masoomeh Amani; Houshang Emami; Seyed Hadi Sajjadi; Hossein Rastgariyan; Mahmood Ghasemi; Behnam Khosravani Fard

    2010-01-01

    Background and Purpose. Fixed orthodontics may be associated with accumulation of Mutans Streptococci (MS), enamel demineralization, and an increased number of carious lesions, predominantly in sites adjacent to brackets. This study was undertaken to assess the effectiveness of Listerine, Oral-B, and Ortho-kin on the accumulation of MS in plaque around orthodontic brackets. Materials and Methods A double-blind randomized cross-over clinical trial on 25 orthodontic patients, classified into 6...

  18. Effect of self-etching primer/adhesive and conventional bonding on the shear bond strength in metallic and ceramic brackets

    OpenAIRE

    Mirzakouchaki, Behnam; Kimyai, Soodabeh; Hydari, Mahboubeh; Shahrbaf, Shirin; Mirzakouchaki-Boroujeni, Parvin

    2011-01-01

    Introduction: Bracket debonding from the tooth surface is a common problem in fixed orthodontics. The aims of the present study were to assess the bond strength and failure sites in two ways of bonding technique, with metallic and ceramic brackets. Material and Methods: One hundred premolars were assigned to 4 groups of 25 each: Group A, metallic brackets/ conventional procedure; Group B, metallic brackets/Transbond XT; Group C, ceramic brackets/conventional procedure; and Grou...

  19. Influência da secção transversa de fios ortodônticos na fricção superficial de braquetes autoligados Influence of the cross-section of orthodontic wires on the surface friction of self-ligating brackets

    Directory of Open Access Journals (Sweden)

    Roberta Buzzoni

    2011-08-01

    Full Text Available OBJETIVO: o objetivo do presente trabalho foi determinar a força de atrito estático entre braquetes de aço inoxidável autoligados com sistema de fechamento resiliente e fios ortodônticos redondos e retangulares do mesmo material. MÉTODOS: empregaram-se 30 braquetes referentes aos caninos superiores divididos em 6 grupos formados por braquetes autoligados Smartclip, In-Ovation R e convencionais Gemini amarrados com ligaduras elásticas. A hipótese testada neste trabalho foi quanto à possibilidade dos braquetes autoligados ativos serem suscetíveis à elevação da força de atrito com o aumento e alteração da secção transversal dos fios ortodônticos. Os ensaios foram realizados com tração de 30s em fios de aço inoxidável 0,020" e 0,019"X0,025" na máquina de ensaios Emic DL 10000, com uma célula de carga de 20 newtons. Cada conjunto braquete/fio foi responsável pela geração de quatro corpos de prova, totalizando 120 leituras. As comparações entre as médias foram realizadas através da Análise de Variância (one way ANOVA com correções pelo coeficiente de Bonferroni. RESULTADOS E CONCLUSÃO: os braquetes autoligados apresentaram maior força de atrito do que os braquetes convencionais amarrados com ligaduras elásticas. O grupo Smartclip foi o mais efetivo no controle do atrito (pOBJECTIVES: The purpose of this study was to assess the surface friction produced by self-ligating stainless steel brackets equipped with a resilient closure system and compare the friction generated during traction of round and rectangular orthodontic wires made from the same material. METHODS: Thirty maxillary canine brackets were divided into six groups comprising SmartClip and In-Ovation R self-ligating brackets, and conventional Gemini brackets tied with elastomeric ligatures. This investigation tested the hypothesis that self-ligating brackets are susceptible to increases in friction that are commensurate with increases and changes in the cross-section of orthodontic wires. Traction was performed with the aid of thirty segments of 0.020" and 0.019" x 0.025" stainless steel wires in an EMIC DL 10000 testing machine with a 2N load cell. Each set of bracket/wire generated four samples, totaling 120 readings. Comparisons between means were performed using analysis of variance (one way ANOVA corrected with the Bonferroni coefficient. RESULTS AND CONCLUSION: The self-ligating brackets exhibited lower friction than conventional brackets tied with elastomeric ligatures. The SmartClip group was the most effective in controlling friction (p <0.01. The hypothesis under test was confirmed to the extent that the traction performed with rectangular 0.019" x 0.025" cross-section wires resulted in higher friction forces than those observed in the 0.020" round wire groups (p<0.01. The SmartClip system was more effective even when the traction produced by rectangular wires was compared with the In-Ovation R brackets combined with round wires (p<0.01.

  20. Estudo comparativo de seis tipos de braquetes ortodônticos quanto à força de adesão / A comparative study of six types of orthodontic brackets with regard to bond strength

    Scientific Electronic Library Online (English)

    Leonardo de Aquino, Fleischmann; Márcio Costa, Sobral; Gildo Coelho, Santos Júnior; Fernando, Habib.

    2008-08-01

    Full Text Available INTRODUÇÃO: a realização de um diagnóstico acurado, assim como a correta seleção de materiais, especificamente dos braquetes, são requisitos importantes para o êxito da terapia ortodôntica. OBJETIVOS: investigar a influência de variados tipos de desenho da base de braquetes na força de adesão. METOD [...] OLOGIA: seis modelos foram avaliados mediante ensaio de cisalhamento - Discovery (Dentaurum) - metálico com retenções por laser e 13,12mm² de área da base; Monobloc (Morelli) - metálico em corpo único com protuberâncias e 10,22mm² de área; Edgewise Standard (Ortho Organizers) - metálico com base MIM (Metal Injection Molding) e 12,02mm² de área; Illusion Plus (Ortho Organizers) - porcelana com sulcos de retenção e 13,49mm² de área; Composite (Morelli) - policarbonato com protuberâncias para retenção mecânica e 14,68mm² de área; e Edgewise Standard (Morelli) - metálico com tela de retenção e 14,31mm² de área. Os braquetes foram colados em dentes bovinos (incisivos) com o sistema adesivo Fill Magic Ortodôntico (Vigodent), para a realização do teste. O ensaio foi executado em uma máquina de ensaios universal (EMIC), e a força de adesão foi computada, no momento da cisão, pelo software TESC, versão 3.01, medida em Newtons (N) e em Megapascal (Mpa). RESULTADOS E CONCLUSÕES: não houve diferença estatística entre os braquetes testados, sendo que o grupo que apresentou a maior média de força de adesão foi o Discovery com 10,12Mpa. Abstract in english INTRODUCTION: An accurate diagnosis as well as the correct selection of materials, brackets in particular, are important pre-requisites for success in orthodontic therapy. AIM: The aim of this study was to examine the influence of various brackets-base designs on bond strength. METHODS: Six models w [...] ere evaluated by a test of sheer bond strength: Discovery (Dentaurum) - metallic with laser grooves and 13.12mm² of base area; Monobloc (Morelli) - metallic one-piece with raised bumps and 10.22mm² of area; Edgewise Standard (Ortho Organizers) - metallic with MIM (Metal Injection Molding) and 12.02mm² of area; Illusion Plus (Ortho Organizers) - ceramic with retention ridges and 13.49mm² of area; Composite (Morelli) - polycarbonate with raised bumps for mechanical retention with 14.68mm² of area; and Edgewise Standard (Morelli) - metallic with single mesh and 14.31mm² of area. The brackets were bonded on bovine teeth with Fill Magic Ortodôntico (Vigodent) bond agent, for testing. The study was conduced in a universal test machine (EMIC), and the bond strength was recorded at the moment of split by TESC software, 3.01 version; it was calculated in newtons (N) and megapascal (Mpa). RESULTS AND CONCLUSIONS: No statistical difference among tested brackets was found, and the group with the greatest average bond strength was Discovery with 10,12Mpa.

  1. Estudo comparativo de seis tipos de braquetes ortodônticos quanto à força de adesão A comparative study of six types of orthodontic brackets with regard to bond strength

    Directory of Open Access Journals (Sweden)

    Leonardo de Aquino Fleischmann

    2008-08-01

    Full Text Available INTRODUÇÃO: a realização de um diagnóstico acurado, assim como a correta seleção de materiais, especificamente dos braquetes, são requisitos importantes para o êxito da terapia ortodôntica. OBJETIVOS: investigar a influência de variados tipos de desenho da base de braquetes na força de adesão. METODOLOGIA: seis modelos foram avaliados mediante ensaio de cisalhamento - Discovery (Dentaurum - metálico com retenções por laser e 13,12mm² de área da base; Monobloc (Morelli - metálico em corpo único com protuberâncias e 10,22mm² de área; Edgewise Standard (Ortho Organizers - metálico com base MIM (Metal Injection Molding e 12,02mm² de área; Illusion Plus (Ortho Organizers - porcelana com sulcos de retenção e 13,49mm² de área; Composite (Morelli - policarbonato com protuberâncias para retenção mecânica e 14,68mm² de área; e Edgewise Standard (Morelli - metálico com tela de retenção e 14,31mm² de área. Os braquetes foram colados em dentes bovinos (incisivos com o sistema adesivo Fill Magic Ortodôntico (Vigodent, para a realização do teste. O ensaio foi executado em uma máquina de ensaios universal (EMIC, e a força de adesão foi computada, no momento da cisão, pelo software TESC, versão 3.01, medida em Newtons (N e em Megapascal (Mpa. RESULTADOS E CONCLUSÕES: não houve diferença estatística entre os braquetes testados, sendo que o grupo que apresentou a maior média de força de adesão foi o Discovery com 10,12Mpa.INTRODUCTION: An accurate diagnosis as well as the correct selection of materials, brackets in particular, are important pre-requisites for success in orthodontic therapy. AIM: The aim of this study was to examine the influence of various brackets-base designs on bond strength. METHODS: Six models were evaluated by a test of sheer bond strength: Discovery (Dentaurum - metallic with laser grooves and 13.12mm² of base area; Monobloc (Morelli - metallic one-piece with raised bumps and 10.22mm² of area; Edgewise Standard (Ortho Organizers - metallic with MIM (Metal Injection Molding and 12.02mm² of area; Illusion Plus (Ortho Organizers - ceramic with retention ridges and 13.49mm² of area; Composite (Morelli - polycarbonate with raised bumps for mechanical retention with 14.68mm² of area; and Edgewise Standard (Morelli - metallic with single mesh and 14.31mm² of area. The brackets were bonded on bovine teeth with Fill Magic Ortodôntico (Vigodent bond agent, for testing. The study was conduced in a universal test machine (EMIC, and the bond strength was recorded at the moment of split by TESC software, 3.01 version; it was calculated in newtons (N and megapascal (Mpa. RESULTS AND CONCLUSIONS: No statistical difference among tested brackets was found, and the group with the greatest average bond strength was Discovery with 10,12Mpa.

  2. Prototype of a new tip developed to be coupled to dental light-curing units for optimizing bonding of orthodontic brackets and accessories

    Scientific Electronic Library Online (English)

    Sergio Luiz, Mota Júnior; Márcio José da Silva, Campos; Marco Abdo, Gravina; Marcelo Reis, Fraga; Robert Willer Farinazzo, Vitral.

    2013-12-01

    Full Text Available OBJETIVO: desenvolver uma nova ponteira para ser acoplada aos aparelhos fotopolimerizadores utilizados para colagem de braquetes e acessórios ortodônticos, e testar sua da efetividade em ensaio mecânico in vitro. A ponteira é espelhada na superfície interna e baseia-se em conceitos físicos de refraç [...] ão e reflexão de luz. Apresenta como principal vantagem o menor tempo clínico durante o procedimento de colagem, reduzindo a possibilidade de contaminação durante o processo. MÉTODOS: por meio de ensaio de resistência ao cisalhamento e determinação do índice remanescente de adesivo (IRA), testou-se a ponteira desenvolvida em 120 corpos de prova. A amostra foi dividia em dois grupos. No grupo 1, foi utilizado aparelho fotopolimerizador de fonte de luz halógena e, no grupo 2, fonte de LED. Cada grupo foi subdividido. Nos subgrupos H1 e L1, utilizou-se a ponteira convencional. Nos subgrupos H2 e L2 a colagem foi feita utilizando a ponteira desenvolvida para a polimerização do material de colagem. RESULTADOS: os valores dos testes de cisalhamento e IRA para os subgrupos foram comparados entre si. Os resultados mostraram que não houve diferença estatisticamente significativa para o ensaio de resistência ao cisalhamento (p > 0,05) nem para o IRA (p > 0,05) entre os subgrupos. CONCLUSÃO: os testes de ensaio mecânico, assim como a análise do IRA, mostraram que a nova ponteira desenvolvida cumpriu os requisitos necessários à colagem dos acessórios ortodônticos, e que o tempo de colagem foi reduzido pela metade, sendo necessária uma só incidência. Abstract in english OBJECTIVE: development of a new device to be coupled to light-curing units for bonding orthodontic brackets and accessories, and test its efficacy in an in vitro mechanical trial. The inner surface of the device is mirrored and is based on physical concepts of light refraction and reflection. The ma [...] in advantage of such device is the reduced clinical time needed for bonding and the low possibility of contamination during the process. METHODS: One hundred and twenty specimens were used for testing the shear bond strength of brackets bonded with the device. The Adhesive Remnant Index (ARI) was also determined. The sample was divided into 2 groups. In group 1 a halogen light-curing unit was used while in group 2 a led light-curing unit was used. Each group was then subdivided. In subgroups H1 and L1, a conventional light guide rod was used while in subgroups H2 and L2 bonding was performed with the mirrored device coupled to the tip of the guide light rod. RESULTS: The values obtained for the shear bond strength and the ARI in the subgroups were compared. Results showed that there was no statistically significant difference for the shear strength (p > 0.05) and the ARI (p > 0.05) between the subgroups. CONCLUSION: The tests of mechanical trials and the ARI analysis showed that the new device fulfilled the requirements for bonding orthodontic accessories, and that the time for bonding was reduced to half, being necessary only one light exposure.

  3. Friction between different wire bracket combinations in artificial saliva: an in vitro evaluation

    Directory of Open Access Journals (Sweden)

    Tatiana Kelly da Silva Fidalgo

    2011-02-01

    Full Text Available OBJECTIVE: The objective this work was to assess the friction coefficient between brackets and wires of different materials under conditions simulating the oral environment. MATERIAL AND METHODS: Stainless steel (SS and titanium-molybdenum alloy (TMA wires of 0.019x0.025-in diameter (American Orthodontics and polycarbonate bracket (American Orthodontics, ceramic bracket (American Orthodontics, and metal bracket (3M Unitek with slots of 0.022x0.030-in were used. The friction coefficient was assessed by means of mechanical traction with the system immersed in artificial saliva. The mean roughness of both wire surface and bracket slots was evaluated by using a surface profilometer. RESULTS: The system using TMA wire and polycarbonate bracket had the highest roughness (p<0.05. SS wire with ceramic bracket had the highest friction coefficient, whereas the use of metallic bracket yielded the lowest (p<0.05. However, it was observed a statistically significant difference in the system using TMA wire and ceramic bracket compared to that using TMA wire and polycarbonate bracket (p=0.038. CONCLUSIONS: Ceramic brackets in association with SS wire should be judiciously used, since this system showed a high friction coefficient.

  4. Evaluation of shear bond strength of orthodontic brackets bonded on the tooth surface after internal bleaching / Avaliação da resistência ao cisalhamento de briquettes ortodônticos colados na superfície dentária após clareamento interno

    Scientific Electronic Library Online (English)

    Nadia de Souza, FERREIRA; Patrícia Campos Ferreira da, ROSA; Raffaela Di Iorio Jeronymo, FERREIRA; Marcia Carneiro, VALERA.

    2014-06-01

    Full Text Available Introdução : O apelo estético de pacientes que possuem dentes escurecidos é grande, pois atualmente os padrões estéticos se tornaram rigorosos e muitos pacientes antes ou durante o tratamento ortodôntico, realizam o procedimento de clareamento dental. Objetivo: Avaliar a adesão de braquetes or [...] todônticos em molares humanos que receberam clareamento interno. Material e método: Quarenta coroas de molares humanos foram divididas em quatro grupos, de acordo com o agente clareador utilizado: SP) perborato de sódio + água; SP) peróxido de carbamida; CP+SP) peróxido de carbamida + perborato de sódio; Cont) água (grupo controle). Os agentes clareadores colocados no interior das câmaras pulpares foram substituídos a cada 7 dias por 2 semanas, e a colagem dos braquetes foi efetuada após 30 dias do final do clareamento. O teste de resistência ao cisalhamento foi realizado em máquina de ensaios universal (Emic). Resultado: O teste estatístico ANOVA com nível de significância de 5% (p > 0,05), mostrou que não houve diferença estatística significante entre os grupos (p = 0,1214). Conclusão: Concluiu-se que os diferentes agentes clareadores estudados não interferem na resistência de adesão dos braquetes ao esmalte dentário e a colagem dos braquetes 30 dias após o clareamento interno é um procedimento seguro. Abstract in english Introduction: There is great demand for esthetic treatment by patients who have discolored teeth, because currently aesthetic standards have become stricter and many patients have tooth bleaching procedures performed before or during orthodontic treatment. Objective: To evaluate the bonding of [...] orthodontic brackets to human molars after internal tooth bleaching. Material and method: Forty molars were divided into four groups according to the bleaching agent used: PS) sodium perborate + water; PC) carbamide peroxide; PC + PS) carbamide peroxide + sodium perborate; Cont) water (control group). Bleaching agents placed inside the pulp chambers were replaced every 7 days for 2 weeks, and the brackets were bonded 30 days after the end of bleaching. The shear strength test was performed in a universal testing machine (Emic). Result: ANOVA with a significance level of 5% (p > 0.05), showed no statistically significant difference between groups (p = 0.1214). Conclusion: It was concluded that the different bleaching agents studied did not interfere with the bond strength of brackets to enamel and bonding the brackets 30 days after internal bleaching is a safe procedure.

  5. Frictional resistance of self-ligating versus conventional brackets in different bracket-archwire-angle combinations

    Directory of Open Access Journals (Sweden)

    Maria Regina Guerra MONTEIRO

    2014-06-01

    Full Text Available Objective: To compare the influence of archwire material (NiTi, beta-Ti and stainless steel and brackets design (self-ligating and conventional on the frictional force resistance. Material and Methods: Two types of brackets (self-ligating brackets - Smartclip, 3M/Unitek - and conventional brackets - Gemini, 3M/Unitek with three (0, 5, and 10 degrees slot angulation attached with elastomeric ligatures (TP Orthodontics were tested. All brackets were tested with archwire 0.019"x0.025" nickel-titanium, beta-titanium, and stainless steel (Unitek/3M. The mechanical testing was performed with a universal testing machine eMIC DL 10000 (eMIC Co, Brazil. The wires were pulled from the bracket slots at a cross-head speed of 3 mm/min until 2 mm displacement. Results: Self-ligating brackets produced significantly lower friction values compared with those of conventional brackets. Frictional force resistance values were directly proportional to the increase in the bracket/ wire angulation. With regard to conventional brackets, stainless steel wires had the lowest friction force values, followed by nickel-titanium and beta-titanium ones. With regard to self-ligating brackets, the nickel-titanium wires had the lowest friction values, significantly lower than those of other materials. Conclusion: even at different angulations, the self-ligating brackets showed significantly lower friction force values than the conventional brackets. Combined with nickel-titanium wires, the self-ligating brackets exhibit much lower friction, possibly due to the contact between nickel-titanium clips and wires of the same material.

  6. Clinical evaluation of the failure rates of metallic brackets

    Scientific Electronic Library Online (English)

    Fábio Lourenço, Romano; Américo Bortolazzo, Correr; Lourenço, Correr-Sobrinho; Maria Beatriz Borges de Araújo, Magnani; Antônio Carlos de Oliveira, Ruellas.

    2012-04-01

    Full Text Available OBJECTIVES: The aim of this study was to evaluate in vivo the bonding of metallic orthodontic brackets with different adhesive systems. MATERIAL AND METHODS: Twenty patients (10.5-15.1 years old) who had sought corrective orthodontic treatment at a University Orthodontic Clinic were evaluated. Brack [...] ets were bonded from the right second premolar to the left second premolar in the upper and lower arches using: Orthodontic Concise, conventional Transbond XT, Transbond XT without primer, and Transbond XT associated with Transbond Plus Self-etching Primer (TPSEP). The 4 adhesive systems were used in all patients using a split-mouth design; each adhesive system was used in one quadrant of each dental arch, so that each group of 5 patients received the same bonding sequence. Initial archwires were inserted 1 week after bracket bonding. The number of bracket failures for each adhesive system was quantified over a 6-month period. RESULTS: The number of debonded brackets was: 8- Orthodontic Concise, 2- conventional Transbond XT, 9- Transbond XT without primer, and 1- Transbond XT + TPSEP. By using the Kaplan-Meier methods, statistically significant differences were found between the materials (p=0.0198), and the Logrank test identified these differences. Conventional Transbond XT and Transbond XT + TPSEP adhesive systems were statistically superior to Orthodontic Concise and Transbond XT without primer (p

  7. Friction between different wire bracket combinations in artificial saliva: an in vitro evaluation

    Scientific Electronic Library Online (English)

    Tatiana Kelly da Silva, Fidalgo; Matheus Melo, Pithon; José Vinicius Bolognesi, Maciel; Ana Maria, Bolognese.

    2011-02-01

    Full Text Available OBJECTIVE: The objective this work was to assess the friction coefficient between brackets and wires of different materials under conditions simulating the oral environment. MATERIAL AND METHODS: Stainless steel (SS) and titanium-molybdenum alloy (TMA) wires of 0.019x0.025-in diameter (American Orth [...] odontics) and polycarbonate bracket (American Orthodontics), ceramic bracket (American Orthodontics), and metal bracket (3M Unitek) with slots of 0.022x0.030-in were used. The friction coefficient was assessed by means of mechanical traction with the system immersed in artificial saliva. The mean roughness of both wire surface and bracket slots was evaluated by using a surface profilometer. RESULTS: The system using TMA wire and polycarbonate bracket had the highest roughness (p

  8. Frictional resistance of self-ligating versus conventional brackets in different bracket-archwire-angle combinations

    Scientific Electronic Library Online (English)

    Maria Regina Guerra, MONTEIRO; Licinio Esmeraldo da, SILVA; Carlos Nelson, ELIAS; Oswaldo de Vasconcellos, VILELLA.

    2014-06-01

    Full Text Available Objective: To compare the influence of archwire material (NiTi, beta-Ti and stainless steel) and brackets design (self-ligating and conventional) on the frictional force resistance. Material and Methods: Two types of brackets (self-ligating brackets - Smartclip, 3M/Unitek - and conventional brack [...] ets - Gemini, 3M/Unitek) with three (0, 5, and 10 degrees) slot angulation attached with elastomeric ligatures (TP Orthodontics) were tested. All brackets were tested with archwire 0.019"x0.025" nickel-titanium, beta-titanium, and stainless steel (Unitek/3M). The mechanical testing was performed with a universal testing machine eMIC DL 10000 (eMIC Co, Brazil). The wires were pulled from the bracket slots at a cross-head speed of 3 mm/min until 2 mm displacement. Results: Self-ligating brackets produced significantly lower friction values compared with those of conventional brackets. Frictional force resistance values were directly proportional to the increase in the bracket/ wire angulation. With regard to conventional brackets, stainless steel wires had the lowest friction force values, followed by nickel-titanium and beta-titanium ones. With regard to self-ligating brackets, the nickel-titanium wires had the lowest friction values, significantly lower than those of other materials. Conclusion: even at different angulations, the self-ligating brackets showed significantly lower friction force values than the conventional brackets. Combined with nickel-titanium wires, the self-ligating brackets exhibit much lower friction, possibly due to the contact between nickel-titanium clips and wires of the same material.

  9. A bracket design proposal for the first molar

    Directory of Open Access Journals (Sweden)

    Roberto Scalon

    2010-07-01

    Full Text Available Introduction: The advent of bracket bonding simplified the assembly of orthodontic braces, besides giving more comfort to the patient and decreasing the risk of decalcification. However, there is no first molar bracket with accessory tube and hooks in the market, except for the convertible type.Objective:To present a patent for utility model of a bracket Roth prescription, Straight-Wire technique for first molar, in order to facilitate orthodontic treatment where there is a need for placing accessories in second molars.Material and methods:This patent consists of a molar bracket for bonding, which contains a retentive base for this, similar to the bracket used in the Edgewise technique,with fins for placing alastic or metal ligature,but containing pre-angles and torques as the tubes of the molar Straight-Wire technique with Roth prescription.It also includes an accessory tube for placing arches or cantilevers and hooks for placing elastics.Results and conclusion:With this bracket design proposal it is possible to obtain an accessory that facilitates the inclusion of the second molar in the assembly of the orthodontic brace without the use of bands.Moreover, this bracket has fins for placing ligatures,accessory tube for placing arches or cantilevers and hooks for placing elastics.

  10. Hypersensitivity to conventional and to nickel-free orthodontic brackets / Hipersensibilidade a bráquetes ortodônticos convencionais e a bráquetes "nickel-free"

    Scientific Electronic Library Online (English)

    Mariele Cristina Garcia, Pantuzo; Elton Gonçalves, Zenóbio; Helenice de Andrade, Marigo; Madelon Aparecida Fernandes, Zenóbio.

    2007-12-01

    Full Text Available Este trabalho teve como objetivo avaliar a capacidade alergênica provocada pelos bráquetes ortodônticos, comparando a sensibilidade cutânea provocada pelos metais presentes nos bráquetes metálicos convencionais com a provocada por bráquetes com baixa concentração de níquel ("nickel-free"). A amostra [...] foi selecionada dos 400 pacientes em tratamento da clínica de Ortodontia da Pontifícia Universidade Católica de Minas Gerais (Belo Horizonte, MG, Brasil), no período compreendido entre o início de 2002 e o final de 2003. A amostra consistiu de 58 pacientes (30 homens e 28 mulheres), com idades variando de 11 a 30 anos, os quais eram portadores de aparelho ortodôntico fixo Morelli® em ambos os arcos. Estes pacientes foram diagnosticados quanto à sensibilidade ao níquel, por meio da aplicação do "patch test" com sulfato de níquel a 5%. Em uma segunda fase, trinta dias após o "patch test", comparou-se a sensibilidade cutânea provocada pelos metais presentes nos bráquetes convencionais e nos "Nickel Free", por meio de um teste de sensibilidade cutânea utilizando-se dois tipos de corpos-de-provas, em formato de disco, com a mesma composição destes bráquetes. A área de eleição para realização deste teste foi a parte interna do antebraço, sendo aplicados vinte corpos-de-prova de cada experimento (referente a uma boca completa de bráquetes). Dos 58 pacientes avaliados, 16 deles foram sensíveis ao "patch test" com sulfato de níquel a 5%. Dentre estes 16 pacientes, 12 deles desenvolveram reação alérgica ao Experimento 1 (corpo-de-prova com níquel), enquanto que no Experimento 2 (corpo-de-prova "Niquel Free") apenas 5 pacientes apresentaram sensibilidade a esta amostra. O teste de McNemar revelou que os corpos-de-prova "nickel-free" provocaram menor reação alérgica quando comparados aos convencionais (p = 0.016). Abstract in english The aim of this study was to evaluate the allergenic potential of orthodontic brackets, comparing the cutaneous sensitivity provoked by metals present in conventional metallic brackets to that provoked by brackets with a low concentration of nickel, known as "nickel-free". A sample was selected from [...] 400 patients undergoing treatment in the orthodontic clinic of the Pontifical Catholic University of Minas Gerais (Belo Horizonte, MG, Brazil), in the period from the beginning of 2002 to the end of 2003. A cutaneous sensitivity patch test containing 5% nickel sulphate was used in 58 patients (30 males and 28 females), aged between 11 and 30, which were using fixed appliances with Morelli® brackets in both arches. In a second phase, 30 days later, a comparative test of cutaneous sensitivity was applied to the whole sample with two types of test specimens, in the form of a disc. Two alloys were tested: discs composed of the alloy used in the construction of conventional brackets and discs composed of a nickel-free alloy. The internal part of the forearm was chosen for testing, and 20 test specimens of each experiment (corresponding to the twenty brackets of a complete fixed appliance) were applied. Of the 58 patients evaluated, 16 patients were sensitive to the patch test with 5% nickel sulphate. Out of these 16 patients, 12 developed an allergic reaction to experiment 1 (test specimen with nickel), while in experiment 2, only 5 patients showed sensitivity to that sample. The McNemar test revealed that the nickel-free test specimens provoked less allergic reaction when compared with the conventional alloy (p = 0.016).

  11. Effect of Fast Curing Lights, Argon Laser, and Plasma Arc on Bond Strengths of Orthodontic Brackets: An In Vitro Study

    OpenAIRE

    M. Hashem-Hoseini; H. Mahmood-Hashemi; F. Soltan-Moradi; Hooshmand, T.; I.HARIRIAN; Motahhary, P.; J. Chalipa

    2008-01-01

    Objective: Nowadays light-cured composites are used widely by orthodontists to bond brackets. As these composites require 20-40 seconds time per tooth to be light cured, more chair-time in needed compared to self-cured composites. In recent years, the argon laser and plasma arc lights have been introduced in dentistry to reduce this curing time. The purpose of this study was to compare bond strength of brackets bonded with the argon la-ser and plasma arc light with those bonded with the conve...

  12. Biodegradação de braquetes ortodônticos: análise por microscopia eletrônica de varredura Analysis of biodegradation of orthodontic brackets using scanning electron microscopy

    OpenAIRE

    Luciane Macedo de Menezes; Rodrigo Matos de Souza; Gabriel Schmidt Dolci; Berenice Anina Dedavid

    2010-01-01

    OBJETIVO: analisar, por meio de microscopia eletrônica de varredura, as alterações químicas e estruturais de braquetes metálicos submetidos a um processo de biodegradação in vitro. MÉTODOS: a amostra foi dividida em dois grupos, de acordo com a marca comercial dos acessórios - Grupo A = Dyna-Lock, 3M/Unitek (AISI 303) e Grupo B = LG Edgewise Standard, American Orthodontics (AISI 316L). Os corpos de prova, aparelhos ortodônticos simulados, permaneceram imersos em solução salina (0,05%) por um ...

  13. Orthodontic brackets removal under shear and tensile bond strength resistance tests – a comparative test between light sources

    International Nuclear Information System (INIS)

    We have investigated if a new LEDs system has enough efficient energy to promote efficient shear and tensile bonding strength resistance under standardized tests. LEDs 470 ± 10 nm can be used to photocure composite during bracket fixation. Advantages considering resistance to tensile and shear bonding strength when these systems were used are necessary to justify their clinical use. Forty eight human extracted premolars teeth and two light sources were selected, one halogen lamp and a LEDs system. Brackets for premolar were bonded through composite resin. Samples were submitted to standardized tests. A comparison between used sources under shear bonding strength test, obtained similar results; however, tensile bonding test showed distinct results: a statistical difference at a level of 1% between exposure times (40 and 60 seconds) and even to an interaction between light source and exposure time. The best result was obtained with halogen lamp use by 60 seconds, even during re-bonding; however LEDs system can be used for bonding and re-bonding brackets if power density could be increased

  14. Biodegradação de braquetes ortodônticos: avaliação da liberação iônica in vitro Biodegradation of orthodontic brackets: in vitro ion release

    OpenAIRE

    Gabriel Schmidt Dolci; Luciane Macedo de Menezes; Rodrigo Matos de Souza; Berenice Anina Dedavid

    2008-01-01

    OBJETIVO: avaliar, in vitro, a biodegradação de aparelhos ortodônticos simulados constituídos de braquetes e fios de aço inoxidável. METODOLOGIA: a amostra foi dividida em 2 grupos, de acordo com a marca dos braquetes usados: grupo A - Dyna-Lock, 3M/Unitek (AISI 303); e grupo B - LG Edgewise Standard, American Orthodontics (AISI 316L). Os corpos-de-prova permaneceram incubados em solução salina (0,05%) a 36ºC, sob agitação por um período de até 60 dias. A análise da liberação iônica foi reali...

  15. Avaliação da influência dos tipos de tratamento superficial da porcelana glazeada na colagem de braquetes ortodônticos / Evaluation of the influence of porcelain conditioning techniques in orthodontic brackets bonding

    Scientific Electronic Library Online (English)

    Camila Belo, Falcão; Adriano Marques, Brito; Fernando Jorge Mendes, Ahid.

    2009-06-01

    Full Text Available OBJETIVO: o objetivo deste trabalho foi avaliar a influência do tipo de tratamento superficial da porcelana na resistência adesiva da colagem de braquetes ortodônticos e o modo de fratura após a descolagem. METODOLOGIA:foram confeccionados 80 corpos-de-prova de porcelana, divididos em quatro grupos [...] (n = 18) de acordo com os diferentes tratamentos de superfície: (G1) ponta diamantada; (G2) ponta diamantada e silano; (G3) ácido hidrofluorídrico e (G4) ácido hidrofluorídrico e silano. Após o preparo das superfícies, braquetes Edgewise (Morelli) foram colados com resina (Transbond XT, 3M) e submetidos ao teste de cisalhamento. Os resultados foram avaliados estatisticamente pelo teste de Kruskal-Wallis. RESULTADO: o grupo G1 apresentou uma média de resistência de 3,35, o G2 3,97, o G3 2,56 e o G4 3,10. CONCLUSÃO: constatou-se que não houve diferença estatisticamente significativa na resistência adesiva do braquete entre os tipos de tratamentos estudados (p > 0,05) e os modos de fratura ocorreram, em sua grande maioria, na interface braquete/resina. Este estudo indica que todos os tipos de tratamentos apresentados são eficientes para a colagem. Abstract in english AIM: The aim of this study was to evaluate the influence of various porcelain surface treatments on the strength of orthodontic brackets bonded to porcelain and the fracture mode after debonding. METHODS: Eighty samples of porcelain were randomly divided into four groups according to their surface p [...] reparation, as follows: (G1) diamond bur, (G2) diamond bur with silane, (G3) hydrofluoridic acid and (G4) hydrofluoridic acid with silane. After surface treatment the Edgewise brackets (Morelli) were bonded with resin (Transbond XT, 3M) and sheared off. The Kruskal-Wallis statistical test were applied on the data. RESULTS: There were no statistically significant differences in bond strength between the groups (p > 0.05) and the fracture mode in most of the porcelain occurred in the composite/bracket interface. The G1 had an resistance average of 3.35, G2 = 3.97, G3 = 2.56 and G4 = 3.10.

  16. Avaliação da influência dos tipos de tratamento superficial da porcelana glazeada na colagem de braquetes ortodônticos Evaluation of the influence of porcelain conditioning techniques in orthodontic brackets bonding

    Directory of Open Access Journals (Sweden)

    Camila Belo Falcão

    2009-06-01

    Full Text Available OBJETIVO: o objetivo deste trabalho foi avaliar a influência do tipo de tratamento superficial da porcelana na resistência adesiva da colagem de braquetes ortodônticos e o modo de fratura após a descolagem. METODOLOGIA:foram confeccionados 80 corpos-de-prova de porcelana, divididos em quatro grupos (n = 18 de acordo com os diferentes tratamentos de superfície: (G1 ponta diamantada; (G2 ponta diamantada e silano; (G3 ácido hidrofluorídrico e (G4 ácido hidrofluorídrico e silano. Após o preparo das superfícies, braquetes Edgewise (Morelli foram colados com resina (Transbond XT, 3M e submetidos ao teste de cisalhamento. Os resultados foram avaliados estatisticamente pelo teste de Kruskal-Wallis. RESULTADO: o grupo G1 apresentou uma média de resistência de 3,35, o G2 3,97, o G3 2,56 e o G4 3,10. CONCLUSÃO: constatou-se que não houve diferença estatisticamente significativa na resistência adesiva do braquete entre os tipos de tratamentos estudados (p > 0,05 e os modos de fratura ocorreram, em sua grande maioria, na interface braquete/resina. Este estudo indica que todos os tipos de tratamentos apresentados são eficientes para a colagem.AIM: The aim of this study was to evaluate the influence of various porcelain surface treatments on the strength of orthodontic brackets bonded to porcelain and the fracture mode after debonding. METHODS: Eighty samples of porcelain were randomly divided into four groups according to their surface preparation, as follows: (G1 diamond bur, (G2 diamond bur with silane, (G3 hydrofluoridic acid and (G4 hydrofluoridic acid with silane. After surface treatment the Edgewise brackets (Morelli were bonded with resin (Transbond XT, 3M and sheared off. The Kruskal-Wallis statistical test were applied on the data. RESULTS: There were no statistically significant differences in bond strength between the groups (p > 0.05 and the fracture mode in most of the porcelain occurred in the composite/bracket interface. The G1 had an resistance average of 3.35, G2 = 3.97, G3 = 2.56 and G4 = 3.10.

  17. Shear bond strength and debonding characteristics of metal and ceramic brackets bonded with conventional acid-etch and self-etch primer systems: An in-vivo study

    Science.gov (United States)

    Mirzakouchaki, Behnam; Sharghi, Reza; Shirazi, Samaneh; Moghimi, Mahsan; Shahrbaf, Shirin

    2016-01-01

    Background Different in-vitro studies have reported various results regarding shear bond strength (SBS) of orthodontic brackets when SEP technique is compared to conventional system. This in-vivo study was designed to compare the effect of conventional acid-etching and self-etching primer adhesive (SEP) systems on SBS and debonding characteristics of metal and ceramic orthodontic brackets. Material and Methods 120 intact first maxillary and mandibular premolars of 30 orthodontic patients were selected and bonded with metal and ceramic brackets using conventional acid-etch or self-etch primer system. The bonded brackets were incorporated into the wire during the study period to simulate the real orthodontic treatment condition. The teeth were extracted and debonded after 30 days. The SBS, debonding characteristics and adhesive remnant indices (ARI) were determined in all groups. Results The mean SBS of metal brackets was 10.63±1.42 MPa in conventional and 9.38±1.53 MPa in SEP system, (P=0.004). No statistically significant difference was noted between conventional and SEP systems in ceramic brackets. The frequency of 1, 2 and 3 ARI scores and debonding within the adhesive were the most common among all groups. No statistically significant difference was observed regarding ARI or failure mode of debonded specimens in different brackets or bonding systems. Conclusions The SBS of metal brackets bonded using conventional system was significantly higher than SEP system, although the SBS of SEP system was clinically acceptable. No significant difference was found between conventional and SEP systems used with ceramic brackets. Total SBS of metal brackets was significantly higher than ceramic brackets. Due to adequate SBS of SEP system in bonding the metal brackets, it can be used as an alternative for conventional system. Key words:Shear bond strength, Orthodontic brackets, Adhesive remnant index, self-etch. PMID:26855704

  18. Coated Rectangular Composite Archwires: A Comparison Of Self-Ligating And Conventional Bracket Systems During Sliding Mechanics

    Science.gov (United States)

    Woods, David Keith

    The purpose of this study was to analyze the resistance to sliding of coated rectangular fiber reinforced composite archwires using various brackets systems and second-order bracket angulations. Resistance to sliding was investigated for eight bracket systems: six self-ligating brackets (four passive and two passive-active) and two conventional brackets. A rectangular fiber reinforced composite archwire of 0.019 x 0.025-in dimension from BiomersRTM SimpliClear was drawn through a three-bracket model system at ten millimeters per minute for 2.5 millimeters. For each bracket, the resistance to sliding was measured at four bracket angulations (0°, 2.5°, 5°, and 10°) in a dry state at room temperature. The fiber reinforced composite archwire produced the lowest sliding resistance with the passive self-ligating bracket system (Damon DQ) at each bracket angulation tested. Overall, self-ligating bracket systems generated lower sliding resistance than conventionally ligated systems, and one passive/active self-ligating bracket system (In-Ovation-R). There was a significant increase in resistance to sliding as bracket angulation increased for all bracket systems tested. Microscopic analysis revealed increased perforation of the archwire coating material as bracket angulations were increased. Our findings show that the rectangular fiber reinforced composite archwire may be acceptable for sliding mechanics during the intermediate stages of orthodontic tooth movement, however more long-term studies are needed.

  19. Evaluation of the influence of dental bleaching with 35% hydrogen peroxide in orthodontic bracket shear bond strength

    Scientific Electronic Library Online (English)

    Marcus Vinicius Neiva Nunes do, Rego; Roanselli Marllon Lima dos, Santos; Leanne Matias Portela, Leal; Carlos Gustavo Silva, Braga.

    2013-04-01

    Full Text Available OBJETIVO: o propósito do presente estudo in vitro foi avaliar a resistência de união de braquetes colados em pré-molares previamente submetidos ao clareamento com peróxido de hidrogênio a 35%. MÉTODOS: foram estudados 21 dentes pré-molares hígidos, divididos aleatoriamente em três grupos (n = 7). O [...] grupo I (G1) incluiu os dentes que não foram submetidos ao clareamento. As superfícies de esmalte dos grupos II (G2) e III (G3) foram submetidas ao processo de clareamento com peróxido de hidrogênio a 35% (Whiteness HP Maxx). No grupo II (G2), após o clareamento, os dentes foram armazenados por 24 horas em água destilada a 37ºC e, em seguida, braquetes metálicos para pré-molares foram colados utilizando resina Transbond XT (3M). O grupo III (G3) também foi submetido ao mesmo procedimento, sete dias após o clareamento. Após a colagem, todos os dentes foram armazenados em água destilada a 37ºC por 24 horas. Todos os grupos foram submetidos ao teste de tração utilizando-se máquina universal de ensaios Emic DL2000 a uma velocidade 0,5mm/min. RESULTADOS E CONCLUSÃO: a resistência à descolagem dos braquetes foi comparada entre os grupos por meio da utilização do teste não paramétrico Kruskall Wallis (p Abstract in english OBJECTIVE: The purpose of this study was to evaluate, in vitro, the bond strength of brackets bonded to premolars previously subjected to bleaching with a 35% hydrogen peroxide. METHODS: Twenty one healthy premolars were selected and randomly divided into three groups (n = 7). Group I (G1) included [...] teeth that were not submitted to bleaching. The enamel surfaces of Groups II (G2) and III (G3) were submitted to a bleaching process with 35% hydrogen peroxide (Whiteness HP Maxx). On Group II (G2), after bleaching, the teeth were stored for 24 hours in distilled water at 98.6 ºF, and then, premolar metallic brackets were bonded using Transbond XT (3M) resin. Group III (G3) was submitted to the same procedure seven days after bleaching. After bonding, all teeth were stored in distilled water at 98.6 ºF for 24 hours. All groups were submitted to a traction test using an EMIC DL2000 universal testing machine at a speed of 0.5 mm/min. RESULTS AND CONCLUSION: The bracket resistance to debonding was compared between the groups by the Kruskal-Wallis nonparametric test (p

  20. Resistência à remoção de braquetes ortodônticos sob ação de diferentes cargas contínuas / Shear bond strength of orthodontic brackets using different static loading application

    Scientific Electronic Library Online (English)

    Carla, Giannini; Paulo Afonso Silveira, Francisconi.

    2008-06-01

    Full Text Available OBJETIVO: testar se existe alteração na resistência adesiva de dois cimentos utilizados na colagem de acessórios ortodônticos ao esmalte dentário bovino, sendo um de polimerização química (Concise ortodôntico) e outro fotopolimerizável (Transbond XT), após a aplicação de cargas contínuas. METODOLOGI [...] A: foram utilizados para este estudo 80 dentes bovinos e 80 braquetes metálicos. O esmalte bovino foi condicionado com ácido fosfórico a 37% por 1 minuto e depois lavado e seco. A aplicação dos adesivos, manipulação e aplicação dos dois cimentos foram feitas de acordo com as instruções dos fabricantes. Após 24 horas, todos os braquetes foram submetidos a cargas contínuas de 30g, 70g e 120g, menos o grupo controle, que não recebeu carga alguma. Os espécimes ficaram imersos em água filtrada por 28 dias dentro de uma estufa a 37°C. Depois deste período, as amostras foram submetidas a testes de cisalhamento em uma Máquina de Ensaios Universal Kratos. Os resultados foram registrados e enviados para análise estatística. CONCLUSÕES: (1) o cimento Concise apresentou maior resistência à remoção que o cimento Transbond XT para todas as cargas utilizadas, (2) não houve diferença estatisticamente significante na resistência adesiva frente às três cargas utilizadas para os dois cimentos testados; (3) no momento da fratura, conforme ocorreu o aumento da carga, a porcentagem de fratura do esmalte diminuiu para o Concise, ao contrário do cimento Transbond XT, onde a porcentagem de fratura de esmalte se manteve constante com o aumento das cargas. Abstract in english AIM: The purpose of this study was to test differences on bond strength between auto-cured (Concise) and light-cured (Transbond XT) cements after static loading and shear test. METHODS: Eighty bovine teeth and metallic orthodontic brackets (Morelli Ortodontia Braquete Edgewise/Rickets) were tested a [...] fter static loads of 30, 70 and 120grs. Bovine enamel was conditioned with 37% phosphoric acid gel for one minute, rinsed and dried. Adhesives were applied and brackets were bonded according to manufacturer’s instructions. Cement thickness was standardized with the use of a heavier Gilmore needle. After 24 hours, half of the specimens were submitted to the static loads of 30, 70 and 120grs. Control group remained unloaded. Then, specimens were immersed in distilled water for 28 days at 37ºC. Afterwards, orthodontic brackets were attached to a loop wire and submitted to a shear force (Máquina de Ensaios Kratos Universal Kratos) under a crosshead speed of 0.5mm/min and load cell of 500Kgf. A two-way ANOVA test (alpha = 0.05) was used to detect significant interactions between cements and static loads. CONCLUSIONS: (1) The Concise cement showed more statistically significant bond strength values than the Transbond XT cement for all static loads; (2) No statistically significant differences were observed regarding static loads for all cements tested and (3) Higher static loads provided less enamel fracture in the Concise group after shear test, whereas in the Transbond XT the rate of enamel fracture remained unchanged regardless of previous load applied.

  1. Quantitative analysis of S. mutans and S. sobrinus cultivated independently and adhered to polished orthodontic composite resins

    OpenAIRE

    Ulises Velazquez-Enriquez; Rogelio Jose Scougall-Vilchis; Rosalia Contreras-Bulnes; Jaime Flores-Estrada; Shinsuke Uematsu; Ryozo Yamaguchi

    2012-01-01

    In Orthodontics, fixed appliances placed in the oral cavity are colonized by microorganisms. OBJECTIVE: The purpose of this study was to quantitatively determine the independent bacterial colonization of S. mutans and S. sobrinus in orthodontic composite resins. MATERIAL AND METHODS: Seven orthodontic composite adhesives for bonding brackets were selected and classified into 14 groups; (GIm, GIs) Enlight, (GIIm, GIIs) Grengloo, (GIIIm, GIIIs) Kurasper F, (GIVm, GIVs) BeautyOrtho Bond, (GVm, G...

  2. O efeito do jateamento do esmalte na força de adesão na colagem de braquetes The effect of air abrasion in enamel adhesion of orthodontic bracket

    Directory of Open Access Journals (Sweden)

    Carla D'Agostini Derech

    2008-06-01

    Full Text Available OBJETIVO: o propósito deste estudo in vitro foi avaliar o efeito do jateamento com óxido de alumínio na adesão de braquetes ortodônticos e compará-lo à tradicional técnica de condicionamento ácido do esmalte. METODOLOGIA: foram utilizados 80 dentes bovinos distribuídos aleatoriamente entre quatro grupos, sendo que a superfície do esmalte foi tratada da seguinte maneira: grupo 1 (somente jateamento com óxido de alumínio, grupo 2 (profilaxia com pedra-pomes e condicionamento com ácido, grupo 3 (jateamento com óxido de alumínio e condicionamento ácido e grupo 4 (somente condicionamento ácido. Após, foi aplicado sistema adesivo e o braquete colado com resina. Os corpos-de-prova foram submetidos ao teste de cisalhamento e análise do IAR. Aos resultados foram aplicados o teste de variância múltipla (ANOVA e a comparação entre pares (Tukey. Para a análise do IAR foi aplicado o teste Qui-quadrado. RESULTADOS: o grupo 1 apresentou a menor resistência ao cisalhamento (3,6MPa e o 3 a maior (13,27MPa. A análise Qui-quadrado do IAR demonstrou que o tratamento da superfície do esmalte tem influência sobre a quantidade de remanescente de resina sobre o esmalte e os grupos 3 e 4 apresentaram a maior quantidade de resina aderida. CONCLUSÕES: o jateamento de óxido de alumínio não deve ser o único procedimento utilizado no preparo da superfície do esmalte na colagem de braquetes, porém, quando associado ao condicionamento ácido, mostrou-se eficaz no aumento da retenção entre esmalte e resina. Novos estudos são necessários visando menor dano do esmalte e adesão satisfatória.AIM: The purpose of this study in vitro was to evaluate the effect of the air abrasion with Al-oxide in the adhesion of orthodontic brackets and compare with traditional technique of acid conditioning of the enamel. METHODS: Eighty bovine teeth distributed randomly between four groups had been used and the surface of the enamel was prepared in the following way: group 1 (only air abrasion, group 2 (enamel pumiced and acid conditioning, group 3 (air abrasion and acid conditioning and group 4 (only acid conditioning. After, adhesive system was applied and bracket was bonded with resin. Shear bond was assessed and analysis of the IAR was performed. Test of multiple variance (ANOVA and the comparison between pairs had been applied (Tukey on the results. For the analysis of the IAR the Qui-square test was applied. RESULTS: Group 1 presented the lowest shear strength (3,6MPa and 3 the greater (13,27MPa. The Qui-square analysis of the IAR demonstrated that the treatment of the enamel surface has influence on the amount of resin remainder on the enamel and groups 3 and 4 had presented the biggest amount of adhered resin. CONCLUSIONS: The air abrasion doesn’t have to be the only procedure used in the preparation of the enamel surface in the brackets bonding, however, when associated to the acid conditioning it revealed efficient in adhesion increase. New studies are necessary aiming at lesser damage of the enamel and satisfactory adhesion.

  3. Interferência dos diferentes glazeamentos na colagem de bráquetes ortodônticos em superfícies cerâmicas / Effects of the different glazed ceramic surfaces on the bond of orthodontic brackets

    Scientific Electronic Library Online (English)

    A. C, Dalvi; A. M, Bolognese.

    2010-06-01

    Full Text Available Foram avaliadas diferentes formas de glazeamento da superfície de porcelana quanto à resistência ao cisalhamento de bráquetes metálicos colados com diferentes cimentos. Quarenta e dois corpos de prova de metalocerâmica foram confeccionados (2 controles) e divididos em quatro grupos de acordo com o t [...] ipo de glazeamento, com camada extra de glaze (G) ou auto-glazeados (AG), e o cimento utilizado, resina fotopolimerizável (r) ou ionômero de vidro resinosos (i), formando os seguintes grupos: Gr, Gi, AGr e AGi com 10 corpos de prova cada grupo. Todas as superfícies dos corpos de prova receberam tratamento com ácido fosfórico 35% por 30 s seguidos de uma camada de silano. Quarenta bráquetes metálicos foram colados. Os corpos de prova foram submetidos a termociclagem e ao teste de resistência ao cisalhamento com uma máquina universal de ensaios mecânicos. Uma amostra de cada grupo após descolagem, remoção da resina e polimento, foi avaliado em microscópio eletrônico de varredura. O índice de fratura coesiva da porcelana foi também avaliado. Os resultados mostram valores acima da média aceitável na literatura para todos os grupos, sendo que o grupo AGr apresentou valor menor (10,38 MPa) e estatisticamente significativo em relação aos demais. A análise no microscópio eletrônico de varredura mostrou que as superfícies, após polimento, não readquirem as características de antes da colagem, apesar de se apresentarem aceitáveis clinicamente. Houve fratura da porcelana em todos os grupos. Conclui-se que é possível se conseguir colagem adequada de bráquetes metálicos em superfícies metalocerâmicas auto-glazeadas e com camada extra de glaze, preservando-o, não necessitando reconhecer previamente a forma de glazeamento. Abstract in english Different glazing techniques for porcelain surface were evaluated in terms of shear bond strength of metallic brackets bonded with different cements. Forty-two metal-ceramic samples were made (2 controls) and then divided into four groups according to type of glazing technique, either using extra gl [...] aze layer (G) or self-glazing material (SG), and type of adhesive material, that is, self-curing resin (r) or resin glass-ionomer cement (i), thus forming the following groups: Gr, Gi, SGr, and SGi with 10 samples each. The whole surface of all samples was treated with 35% phosphoric acid for 30 s, followed by application of silane layer. Forty metallic brackets were bonded. The samples were submitted to thermocycling process and shear bond strength test with a universal testing machine. After bracket debonding, removal of resin, and polishing, one sample from each group was evaluated with a scanning electron microscope (SEM). The index of cohesive porcelain fracture was also assessed. The results show that all the groups had, on average, values higher than those found in the literature, with AGr presenting the lowest value (10.38 MPa) compared to other groups. SEM analysis showed that the porcelain surfaces did not recover their original characteristics before the bracket debonding procedure, although they were considered acceptable for clinical use. Porcelain fracture was observed in all groups. One can conclude that it is possible to bond metallic brackets adequately to metal-ceramic porcelain surfaces previously treated with either self-glazing material or extra glaze layer without having to recognise the glazing technique originally employed.

  4. Interferência dos diferentes glazeamentos na colagem de bráquetes ortodônticos em superfícies cerâmicas Effects of the different glazed ceramic surfaces on the bond of orthodontic brackets

    Directory of Open Access Journals (Sweden)

    A. C Dalvi

    2010-06-01

    Full Text Available Foram avaliadas diferentes formas de glazeamento da superfície de porcelana quanto à resistência ao cisalhamento de bráquetes metálicos colados com diferentes cimentos. Quarenta e dois corpos de prova de metalocerâmica foram confeccionados (2 controles e divididos em quatro grupos de acordo com o tipo de glazeamento, com camada extra de glaze (G ou auto-glazeados (AG, e o cimento utilizado, resina fotopolimerizável (r ou ionômero de vidro resinosos (i, formando os seguintes grupos: Gr, Gi, AGr e AGi com 10 corpos de prova cada grupo. Todas as superfícies dos corpos de prova receberam tratamento com ácido fosfórico 35% por 30 s seguidos de uma camada de silano. Quarenta bráquetes metálicos foram colados. Os corpos de prova foram submetidos a termociclagem e ao teste de resistência ao cisalhamento com uma máquina universal de ensaios mecânicos. Uma amostra de cada grupo após descolagem, remoção da resina e polimento, foi avaliado em microscópio eletrônico de varredura. O índice de fratura coesiva da porcelana foi também avaliado. Os resultados mostram valores acima da média aceitável na literatura para todos os grupos, sendo que o grupo AGr apresentou valor menor (10,38 MPa e estatisticamente significativo em relação aos demais. A análise no microscópio eletrônico de varredura mostrou que as superfícies, após polimento, não readquirem as características de antes da colagem, apesar de se apresentarem aceitáveis clinicamente. Houve fratura da porcelana em todos os grupos. Conclui-se que é possível se conseguir colagem adequada de bráquetes metálicos em superfícies metalocerâmicas auto-glazeadas e com camada extra de glaze, preservando-o, não necessitando reconhecer previamente a forma de glazeamento.Different glazing techniques for porcelain surface were evaluated in terms of shear bond strength of metallic brackets bonded with different cements. Forty-two metal-ceramic samples were made (2 controls and then divided into four groups according to type of glazing technique, either using extra glaze layer (G or self-glazing material (SG, and type of adhesive material, that is, self-curing resin (r or resin glass-ionomer cement (i, thus forming the following groups: Gr, Gi, SGr, and SGi with 10 samples each. The whole surface of all samples was treated with 35% phosphoric acid for 30 s, followed by application of silane layer. Forty metallic brackets were bonded. The samples were submitted to thermocycling process and shear bond strength test with a universal testing machine. After bracket debonding, removal of resin, and polishing, one sample from each group was evaluated with a scanning electron microscope (SEM. The index of cohesive porcelain fracture was also assessed. The results show that all the groups had, on average, values higher than those found in the literature, with AGr presenting the lowest value (10.38 MPa compared to other groups. SEM analysis showed that the porcelain surfaces did not recover their original characteristics before the bracket debonding procedure, although they were considered acceptable for clinical use. Porcelain fracture was observed in all groups. One can conclude that it is possible to bond metallic brackets adequately to metal-ceramic porcelain surfaces previously treated with either self-glazing material or extra glaze layer without having to recognise the glazing technique originally employed.

  5. Avaliação do uso do Self Etching Primer na colagem de braquetes ortodônticos metálicos Assessment of the Self-Etching Primer on bonding of metallic orthodontic brackets

    Directory of Open Access Journals (Sweden)

    Adriane Regina Sponchiado

    2005-06-01

    Full Text Available Nesta pesquisa laboratorial foi avaliada a resistência de união ao cisalhamento de braquetes metálicos colados ao esmalte dentário bovino, utilizando um sistema adesivo convencional, composto de ácido fosfórico + primer + resina adesiva, e de um sistema SEP (self-etching primer que combina ácido e primer em uma única solução, avaliado em ambiente seco e úmido (com água. Quarenta e oito incisivos inferiores bovinos foram divididos em três grupos de 16 unidades, que foram assim preparados: grupo 1 (controle ácido fosfórico 37% + primer + resina Transbond XT; o grupo 2 Transbond Plus Self Etching Primer em ambiente seco + resina Transbond XT e no grupo 3 o Transbond Plus Self Etching Primer foi aplicado em ambiente úmido com água + Transbond XT. Efetuada a colagem, procedeu-se o ensaio mecânico em uma máquina Instron, a uma velocidade de 1mm/min. As médias da resistência de união ao cisalhamento encontradas foram: 9,29MPa para o grupo 1; 10,57MPa para o grupo 2 e 7,45MPa para o grupo 3, sendo que os três grupos apresentaram resistência compatível com o uso clínico. Não houve diferença estatisticamente significante entre o sistema convencional e o SEP em ambiente seco, nem em ambiente úmido. Houve redução significativa na resistência de união ao cisalhamento para o SEP em ambiente úmido quando comparado ao SEP em ambiente seco. Concluímos que o Transbond Plus Self Etching Primer apresenta resistência de união ao esmalte similar ao ácido fosfórico 37% + primer, sendo indicado para uso clínico na colagem de braquetes ortodônticos.This research evaluated the shear bond strength of metallic brackets bonded to bovine teeth, using conventional adhesive system consisting of phosphoric acid + primer + adhesive resin, and a system SEP (self-etching primer that combines acid and primer in one solution. The SEP system was evaluated in either dry and moist (water environments. Forty-eight lower bovine incisors teeth were divided in three groups of sixteen units each one, prepared as following: group 1(control phosphoric acid 37% + primer + Transbond XT resin; group 2 Transbond Plus Self Etching Primer in dry environment + Transbond XT resin, and group 3 the Transbond Plus Self Etching Primer applied in moist environment + Transbond XT.After bonding, the mechanical test was performed with an Instron machine (crosshead speed of 1mm/min. The shear bond strength were: 9,29 MPa for group 1;10,57 MPa for group 2 and 7,45 MPa for group 3.All groups showed clinical acceptable resistance. There wasn't significant difference between conventional system and the SEP in dry environment, neither in moist environment. However, there was a significant reduction in the shear bond strength for the SEP in moist environment when compared with SEP in dry environment. It was concluded that Transbond + Self Etching Primer showed shear bond strength to enamel similar to phosphoric acid 37% + primer, therefore it is indicated to clinically bond orthodontic brackets.

  6. Avaliação do Índice de Remanescente Adesivo utilizando braquetes com e sem tratamento na base e a interação com três sistemas de colagem Evaluation of Adhesive Remnant Index using conventional mesh bases and sandblasted orthodontic bracket bases and three bonding systems

    Directory of Open Access Journals (Sweden)

    Lilian Maria Brisque Pignatta

    2009-02-01

    Full Text Available OBJETIVO: avaliar o Índice de Remanescente Adesivo (IRA em dentes bovinos após a descolagem de braquetes com e sem tratamento na base. METODOLOGIA: foram utilizados três sistemas de colagem ortodôntica para os dois padrões de base. Os dentes bovinos foram divididos em seis grupos de 40, de acordo com a base do braquete e o sistema de colagem. Vinte e quatro horas após a colagem foram realizados os testes de compressão em uma máquina de ensaios. A avaliação do IRA foi realizada em um estereomicroscópio por três examinadores calibrados. Foi utilizado o teste não paramétrico de Kruskal-Wallis, seguido do método de Dunn, para fazer as comparações múltiplas entre todos os grupos. RESULTADOS E CONCLUSÕES: observou-se que o tratamento das bases dos braquetes com óxido de alumínio não foi determinante para o aumento da adesividade entre o braquete e o adesivo. O grupo em que se utilizou braquetes com tratamento na base e adesivo TXT (3M-Unitek + Transbond Plus SEP (3M-Unitek apresentou a maior parte das fraturas na interface dente-adesivo (escore 4.AIM: To assess the Adhesive Remnant Index (ARI in bovine teeth after debonding mesh bases and sandblasted orthodontic bracket bases. METHODS: Were used three bonding systems for the two standards of base. The bovine teeth were divided into 6 groups of 40, according to the bracket base and to the bonding system. Twenty four hours after bonding they had been carried through shear bond strength tests in a universal testing machine. The assessment of ARI was performed in a stereomicroscopy by three calibrated examiners. It was used the non-parametric Kruskall-Wallis test, followed by Dunn's method, to do the multiple comparisons among all groups. RESULTS AND CONCLUSIONS: It was observed that the aluminum oxide sandblasting bracket bases was not determinative to the increase of the adhesiveness between bracket and adhesive. The group where it was used sandblasted orthodontic bracket bases and bonding system TXT (3M-Unitek + Transbond Plus SEP (3M-Unitek presented the majority of the failures at the teeth-adhesive interface (score 4.

  7. Effect of light-curing units in shear bond strength of metallic brackets: an in vitro study

    OpenAIRE

    Luciana Borges Retamoso; Niége Michelle Lazzari Onofre; Luciane Hann; Ernani Menezes Marchioro

    2010-01-01

    OBJECTIVES: To determine the influence of the light curing units on the shear bond strength of orthodontic brackets. MATERIAL AND METHODS: Seventy-two premolars were divided into six groups (n=12): Group I: brackets bonded with Transbond and polymerization with halogen light; Group II: Transbond and LED; Group III: Fuji Ortho and halogen light; Group IV: Fuji Ortho and LED; Group V: Fuji Ortho, without acid and halogen light; Group VI: Fuji Ortho, without acid and LED. The groups were tested ...

  8. Evaluación in vitro de la resistencia friccional entre brackets cerámicos y arcos de acero inoxidable con y sin recubrimiento vítreo aplicado por el método Sol-Gel / In vitro evaluation of frictional resistance between ceramic brackets and orthodontic steel wires with and without glass coatings applied by Sol-Gel method

    Scientific Electronic Library Online (English)

    Luz Adriana, Rendón Arias; Gustavo Adolfo, Cano Correa; Alejandro, peláez Vargas; Pedro M, Jaramillo Vallejo; Claudia, García Garcia; Yessid, Montoya Góez.

    2008-12-01

    Full Text Available INTRODUCCIÓN: comparar la resistencia friccional estática y dinámica in vitro entre brackets cerámicos y alambres de acero inoxidable con recubrimiento vítreo aplicado por el método Sol-Gel y sin él. MÉTODOS: se prepararon 58 alambres de acero inoxidable AISI 304 de 0.016 x 0.016 con recubrimiento v [...] ítreo aplicado por Sol-Gel y sin él. Posteriormente se evaluó la resistencia a la fricción estática y dinámica in vitro de los alambres sobre brackets cerámicos de zafiro monocristalino y se caracterizaron las superficies en contacto por microscopia óptica y electrónica de barrido (SEM). RESULTADOS: se encontraron diferencias estadísticamente significativas entre ambos grupos tanto para la fuerza de fricción estática (p = 0,000) como dinámica (p = 0,001). El grupo de los alambres recubiertos presentó una fuerza de fricción estática y dinámica mayor (estática: 1,78 ± 0,44 N, dinámica: 1,75 ± 0,49 N) que el grupo sin recubrimientos (estática: 1,37 ± 0,31 N, dinámica: 1,41 ± 0,27 N). La caracterización por SEM mostró que se producen defectos superficiales en los recubrimientos después de las pruebas de fricción. CONCLUSIÓN: los recubrimientos evaluados no mostraron mejor comportamiento friccional sobre brackets de zafiro monocristalino cuando son comparados con el grupo control. Abstract in english INTRODUCTION: to compare the in vitro static and dynamic frictional resistance between ceramic brackets and stainless steel wires with and without glass coatings applied by sol-gel method. METHODS: 58 commercial stainless steel orthodontic wires AISI 304 (0.016 x 0.016 inch) were prepared with and w [...] ithout vitreous coating applied by Sol- Gel method. The in vitro static and dynamic frictional resistance of the wires on the mono-crystalline ceramic brackets were evaluated; also, the wire surfaces were characterized by means of Optical Microscopy and scanning electronic microscopy (SEM). RESULTS: statistically significant differences were found between both groups under static (p = 0.000) as well as dynamic (p = 0.001) friction test. The friction values found in the coated group were higher (Static friction: 1.78 ± 0.44 N, Dynamic friction: 1.75 ± 0.49 N) than the group with no coating (Static friction: 1.37 ± 0.31 N, Dynamic friction: 1.41 ± 0.27 N). Characterization by SEM showed surface defects in both groups after the friction tests. CONCLUSION: the evaluated coatings did not perform better in terms of frictional behavior on sapphire mono-crystalline ceramic brackets when compared with the control group.

  9. Application of particle-induced X-ray emission, backscattering spectrometry and scanning electron microscopy in the evaluation of orthodontic materials

    International Nuclear Information System (INIS)

    The focus of this investigation was on orthodontic materials used in the manufacture of dental brackets. The properties of these dental materials are subjected to various physical parameters such as elongation, yield strength and elasticity that justify their application. In turn, these parameters depend on the quantitative elemental concentration distribution (QECD) in the materials used in the manufacture. For compositional analysis, proton-induced X-ray emission (PIXE), backscatter spectrometry (BS) and scanning electron microscopy (SEM) were applied. QECD analysis was performed to correlate the physical parameters with the composition and to quantify imperfections in the materials. PIXE and BS analyses were performed simultaneously with a 3 MeV proton beam while electrons accelerated at 25 keV were used for the SEM analysis. From the QECDs it was observed that: (1) the major elements Cr, Fe and Ni were homogeneously distributed in the orthodontic plate; (2) the distribution of Mo and O correlated with one another; (3) there was a spread of Cr around regions of high C concentration; and, (4) areas of high concentrations of Mo and O corresponded to a decrease in C concentrations. Elemental concentration correlations are shown to indicate the similarities and differences in the ease of formation of phases, based on the tangent of linearity. (author)

  10. Fracture strength of different soldered and welded orthodontic joining configurations with and without filling material

    Scientific Electronic Library Online (English)

    Jens Johannes, Bock; Jacqueline, Bailly; Christian Ralf, Gernhardt; Robert Andreas Werner, Fuhrmann.

    2008-10-01

    Full Text Available The aim of this study was to compare the mechanical strength of different joints made by conventional brazing, TIG and laser welding with and without filling material. Five standardized joining configurations of orthodontic wire in spring hard quality were used: round, cross, 3 mm length, 9 mm lengt [...] h and 7 mm to orthodontic band. The joints were made by five different methods: brazing, tungsten inert gas (TIG) and laser welding with and without filling material. For the original orthodontic wire and for each kind of joint configuration or connecting method 10 specimens were carefully produced, totalizing 240. The fracture strengths were measured with a universal testing machine (Zwick 005). Data were analyzed by ANOVA (p=0.05) and Bonferroni post hoc test (p=0.05). In all cases, brazing joints were ruptured on a low level of fracture strength (186-407 N). Significant differences between brazing and TIG or laser welding (p

  11. Avaliação da resistência ao cisalhamento de braquetes colados com resinas ortodônticas fluoretadas Evaluation of shear bond strength of brackets bonded with orthodontic fluoride-releasing composite resins

    Directory of Open Access Journals (Sweden)

    Marcia Cristina Rastelli

    2010-06-01

    Full Text Available OBJETIVO: avaliar a resistência ao cisalhamento de braquetes metálicos colados com resinas que contêm flúor, comparando-as a uma resina convencional; e analisar a quantidade de adesivo remanescente na superfície do esmalte. MÉTODOS: sessenta pré-molares foram divididos aleatoriamente em 3 grupos: Grupo I - Concise (3M, Grupo II - Ultrabond (Aditek do Brasil e Grupo III - Rely-a-Bond (Reliance. Após a colagem dos braquetes, as amostras foram termocicladas (500 ciclos nas temperaturas de 5°C e 55°C. Após 48 horas, foram submetidas aos ensaios mecânicos de cisalhamento na direção oclusocervical, com velocidade de carga de 0,5mm/min, em uma máquina MTS 810. RESULTADOS: foram observadas resistências médias ao cisalhamento de 24,54±6,98MPa para o Grupo I, de 11,53±6,20MPa para o Grupo II e de 16,46±5,72MPa para o Grupo III. A Análise de Variância determinou diferença estatística entre as médias de resistência ao cisalhamento entre os grupos (p OBJECTIVE: To evaluate the shear bond strength of stainless steel brackets bonded with fluoride releasing composite resins, comparing them with a conventional resin and to analyze the amount of resin left on the enamel surface. METHODS: Sixty premolars were randomly divided into three groups: Group I - Concise (3M, Group II - Ultrabond (Aditek do Brasil and Group III - Rely-a-Bond (Reliance. After bonding, the samples were thermocycled (500 cycles at 5ºC and 55ºC temperatures. After 48 hours they were subjected to shear bond strength testing, in the occluso-gingival direction, using an MTS 810 Universal Testing Machine with load speed of 0.5 mm/min. RESULTS: The results demonstrated a mean shear bond strength of 24.54 ± 6.98 MPa for Group I, 11.53 ± 6.20 MPa for Group II, and 16.46 ± 5.72 MPa for Group III. Analysis of Variance (ANOVA determined a statistical difference in the mean shear bond strengths between groups (p < 0.001. The Tukey test evidenced that the averages of the three groups were significantly different (p < 0.05, with the highest values for Group I and the lowest for Group II. The Kruskal-Wallis test did not show significant differences in the amount of resin left on the enamel in any of the three groups (p = 0.361. CONCLUSION: All materials exhibited adequate adhesive bond strength for clinical use. Concise exhibited the highest degree of shear bond strength but no significant differences were found in Adhesive Remnant Index (ARI between the groups.

  12. Nanoparticles in orthodontics, a review of antimicrobial and anti-caries applications.

    Science.gov (United States)

    Borzabadi-Farahani, Ali; Borzabadi, Ebrahim; Lynch, Edward

    2014-08-01

    Nanoparticles (NPs) are insoluble particles smaller than 100 nm in size. In order to prevent microbial adhesion or enamel demineralization in orthodontic therapy, two broad strategies have been used. These are incorporating certain NPs into orthodontic adhesives/cements or acrylic resins (nanofillers, silver, TiO2, SiO2, hydroxyapatite, fluorapatite, fluorohydroxyapatite) and coating surfaces of orthodontic appliances with NPs (i.e. coating bracket surfaces with a thin film of nitrogen-doped TiO2). Although the use of NPs in orthodontics can offer new possibilities, previous studies investigated the antimicrobial or physical characteristic over a short time span, i.e. 24 hours to a few weeks, and the limitations of in vitro studies should be recognized. Information on the long-term performance of orthodontic material using nanotechnology is lacking and necessitates further investigation and so do possible safety issues (toxicity), which can be related to the NP sizes. PMID:24325608

  13. Plaque accumulation and Streptococcus mutans levels around self-ligating bracket clips and elastomeric modules: A randomized controlled trial

    Directory of Open Access Journals (Sweden)

    Dhaval Fadia

    2015-01-01

    Full Text Available Aim: To determine the effect of two different ligating systems that is, elastomeric modules and self-ligating (SL bracket systems (Smartclip - 3M Unitek with respect to harboring bacterial plaque in fixed orthodontic treatment. Objectives: To assess, evaluate, and compare the amount of plaque accumulation and Streptococcus mutans colonization around elastomeric ligation and SL clips in the smart clip appliance. Materials and Methods: A total of 111 orthodontic patients scheduled for fixed orthodontic treatments were selected for this split maxillary arch study. All the patients were bonded with smart-clip (3M Unitek SL brackets, and the wire was placed into the bracket slots, on the randomly selected hemi arch, elastomeric modules were placed for the study to be conducted. Microbial and periodontal plaque accumulation was recorded at 3-time intervals post ligation. Plaque index-by Silness and Loe, modified Quigely Hein index, bleeding on probing were evaluated, and biofilm was collected from the tooth surface after 30 days and placed in petri dishes containing Mitis Salivarius agar for bacterial culturing. Result: It was observed that the side where ligation was done with elastomeric modules accumulated more plaque and increase in S. mutans colony forming units as compared to the side without external ligation (P < 0.05. Conclusion: Reduced bacterial colonization and better plaque control was seen with SL orthodontic bracket appliance system as compared to conventional ligation method.

  14. Comparative bond strength of brackets cured using a pulsed xenon curing light with 2 different light-guide sizes.

    Science.gov (United States)

    Oesterle, Larry J; Newman, Sheldon M; Shellhart, W Craig

    2002-09-01

    Light curing of composite resin material beneath orthodontic brackets is common in clinical orthodontics. Experiences with composite resins and high-intensity lights indicate some advantages to staged curing of the composite. In this study, the shear/peel bond strength of orthodontic brackets bonded to bovine enamel and cured with a pulsed xenon plasma arc light was compared with that of bonds cured with a conventional tungsten-quartz-halogen light and a nonpulsed xenon plasma arc light. The pulsed light provided less light energy than the nonpulsed lights. A small and a larger light-guide tip were used with the pulsed xenon plasma arc light. Three different orthodontic composite resin adhesives were tested with each light. The pulsed xenon plasma arc light resulted in either the same or decreased shear/peel bond strength when compared with the nonpulsed lights. There appeared to be no advantage to the use of a pulsed xenon plasma arc light in bonding orthodontic brackets. Results from using either a small or a large light-guide tip varied with the adhesive tested. PMID:12226604

  15. Evaluación in vitro de la resistencia friccional entre brackets cerámicos y arcos de acero inoxidable con y sin recubrimiento vítreo aplicado por el método Sol-Gel In vitro evaluation of frictional resistance between ceramic brackets and orthodontic steel wires with and without glass coatings applied by Sol-Gel method

    Directory of Open Access Journals (Sweden)

    Luz Adriana Rendón Arias

    2008-12-01

    Full Text Available INTRODUCCIÓN: comparar la resistencia friccional estática y dinámica in vitro entre brackets cerámicos y alambres de acero inoxidable con recubrimiento vítreo aplicado por el método Sol-Gel y sin él. MÉTODOS: se prepararon 58 alambres de acero inoxidable AISI 304 de 0.016 x 0.016 con recubrimiento vítreo aplicado por Sol-Gel y sin él. Posteriormente se evaluó la resistencia a la fricción estática y dinámica in vitro de los alambres sobre brackets cerámicos de zafiro monocristalino y se caracterizaron las superficies en contacto por microscopia óptica y electrónica de barrido (SEM. RESULTADOS: se encontraron diferencias estadísticamente significativas entre ambos grupos tanto para la fuerza de fricción estática (p = 0,000 como dinámica (p = 0,001. El grupo de los alambres recubiertos presentó una fuerza de fricción estática y dinámica mayor (estática: 1,78 ± 0,44 N, dinámica: 1,75 ± 0,49 N que el grupo sin recubrimientos (estática: 1,37 ± 0,31 N, dinámica: 1,41 ± 0,27 N. La caracterización por SEM mostró que se producen defectos superficiales en los recubrimientos después de las pruebas de fricción. CONCLUSIÓN: los recubrimientos evaluados no mostraron mejor comportamiento friccional sobre brackets de zafiro monocristalino cuando son comparados con el grupo control.INTRODUCTION: to compare the in vitro static and dynamic frictional resistance between ceramic brackets and stainless steel wires with and without glass coatings applied by sol-gel method. METHODS: 58 commercial stainless steel orthodontic wires AISI 304 (0.016 x 0.016 inch were prepared with and without vitreous coating applied by Sol- Gel method. The in vitro static and dynamic frictional resistance of the wires on the mono-crystalline ceramic brackets were evaluated; also, the wire surfaces were characterized by means of Optical Microscopy and scanning electronic microscopy (SEM. RESULTS: statistically significant differences were found between both groups under static (p = 0.000 as well as dynamic (p = 0.001 friction test. The friction values found in the coated group were higher (Static friction: 1.78 ± 0.44 N, Dynamic friction: 1.75 ± 0.49 N than the group with no coating (Static friction: 1.37 ± 0.31 N, Dynamic friction: 1.41 ± 0.27 N. Characterization by SEM showed surface defects in both groups after the friction tests. CONCLUSION: the evaluated coatings did not perform better in terms of frictional behavior on sapphire mono-crystalline ceramic brackets when compared with the control group.

  16. Influência do agente clareador peróxido de carbamida a 10% na resistência mecânica da colagem de braquetes ortodônticos Influence of 10% carbamide peroxide gel on the shear bond strength of orthodontic brackets

    Directory of Open Access Journals (Sweden)

    Edgard Norões R. da Matta

    2005-04-01

    Full Text Available O propósito deste estudo in vitro foi determinar a influência do agente clareador peróxido de carbamida a 10% na resistência mecânica da colagem de braquetes ortodônticos. Foram estudados três grupos denominados G1 (não submetido ao clareamento, G2 (com clareamento e colagem realizada 1 semana após e G3 (com clareamento e colagem realizada 24h após. O teste de cisalhamento foi conduzido na máquina de ensaios mecânicos Emic, com a velocidade de deformação de 0,5 mm/min.A resitência ao cisalhamento em relação à área de colagem foi calculada para cada dente e expressa em MPa. Os resultados mostraram aumento estatisticamente significante (pThe purpose of this in vitro study was to determine the influence of 10% carbamide peroxide gel on the shear bond strength of orthodontic brackets. Three group were studied: G1 (without bleaching, G2 (bleaching and bonding after 1 week and G3 (bleaching and bonding after 24h. The shear test was conduced in a Emic testing machine with a crosshead speed of 0,5 mm/min. The shear bond strength was calculated for each tooth and expressed in MPa. The results show enhance statistical significant (p<0,001 on the shear bond strength after bleaching and encreased with the time interval between bleaching and bonding, significantily.

  17. A study in vitro on radiation effects by Er:YAG laser combined with the fluorine therapy in the acid resistance of the dental enamel submitted to orthodontical brackets

    International Nuclear Information System (INIS)

    Several researches have been demonstrating an increase in the resistance acid of the enamel surface when irradiated by some lasers types as Nd:YAG, C02, Er:YAG, and others, mainly when combined with the fluoride therapy after the irradiation of the laser. This study in vitro used the laser of Er:YAG which density of energy of 8.1 J/cm2 on the enamel about of orthodontical brackets of teeth extracted pre-molars. These teeth were then submitted to a rich way in S. mutans for twenty one days. The cases were analyzed: (1) enamel surface without any treatment, (2) enamel surface without any irradiation laser, but with therapy with acidulated phosphate fluoride, (3) enamel surface irradiated with laser of Er:YAG and (4) enamel surface irradiated by laser of Er:YAG and with application of acidulated phosphate fluoride. The results were analyzed through optical microscopy and scanning electron microscopy. The morphologic changes observed to the scanning electron microscopy suggest increase in the acid resistance of the enamel surface. However, to the optical microscopy, it was still possible to visualize undesirable white stains in the surface of the enamel. (author)

  18. Biocompatibilidade dos materiais em Ortodontia: mito ou realidade? Biocompatibility of orthodontic materials: myth or reality?

    Directory of Open Access Journals (Sweden)

    Luciane Macedo de Menezes

    2009-04-01

    Full Text Available O objetivo deste trabalho é apresentar uma revisão sobre os conceitos relacionados à biocompatibilidade dos materiais empregados em Ortodontia. Fatos relacionados às reações de hipersensibilidade aos diversos materiais ortodônticos são discutidos, sendo apresentadas as condutas recomendáveis nestas situações.The aim of this paper is to present a review on the biocompatibility of orthodontic materials. Hypersensitivity reactions to these materials are discussed and the recommended conduct in this kind of situation are presented.

  19. Comparison of Antibacterial Effects of ZnO and CuO Nanoparticles Coated Brackets against Streptococcus Mutans

    Directory of Open Access Journals (Sweden)

    Baratali Ramazanzadeh

    2015-09-01

    Full Text Available Statement of the Problem: During the orthodontic treatment, microbial plaques may accumulate around the brackets and cause caries, especially in high-risk patients. Finding ways to eliminate this microbial plaque seems to be essential. Purpose: The aim of this study was to compare the antibacterial effects of nano copper oxide (CuO and nano zinc oxide (ZnO coated brackets against Streptococcus mutans (S.mutans in order to decrease the risk of caries around the orthodontic brackets during the treatment. Materials and Method: Sixty brackets were coated with nanoparticles of ZnO (n=20, CuO (n=20 and CuO-ZnO (n=20. Twelve uncoated brackets constituted the control group. The brackets were bonded to the crowns of extracted premolars, sterilized and prepared for antimicrobial tests (S.mutans ATCC35668. The samples taken after 0, 2, 4, 6 and 24 hours were cultured on agar plates. Colonies were counted 24 hours after incubation. One-way ANOVA and Tukey tests were used for statistical analysis. Results: In CuO and CuO-ZnO coated brackets, no colony growth was seen after two hours. Between 0-6 hours, the mean colony counts were not significantly different between the ZnO and the control group (p>0.05. During 6-24 hours, the growth of S.mutans was significantly reduced by ZnO nanoparticles in comparison with the control group (p< 0.001. However, these bacteria were not totally eliminated. Conclusion: CuO and ZnO-CuO nanoparticles coated brackets have better antimicrobial effect on S.mutans than ZnO coated brackets.

  20. A clinical trial comparing the failure rates of two orthodontic bonding systems.

    Science.gov (United States)

    Trimpeneers, L M; Dermaut, L R

    1996-11-01

    A clinical trial was carried out to compare the failure rates of a visible light-cured fluoride-releasing material with a chemically cured adhesive. Fifty patients were used for the trial and 762 brackets were bonded in a split-mouth experimental design. Bracket failures were reported over the full period of orthodontic treatment. Statistical data analysis was carried out by means of chi 2 tests. The results of this study indicate that brackets, bonded with a chemically cured material (Lee Insta-bond, Lee Pharmaceuticals, EI Monte, Calif.), showed significantly fewer failures than brackets bonded with the light-cured material (Orthon, Orthon Dental Inc., Victoria, Canada). When the site of bond failure was evaluated in an overall manner, there were significantly more lower than upper, and more posterior than anterior bond failures. PMID:8922515

  1. Avaliação da atividade antimicrobiana de adesivo ortodôntico associado a verniz de clorexidina e timol na colagem de braquetes Evaluation of antimicrobial activity of orthodontic adhesive associated with chlorhexidine-thymol varnish in bracket bonding

    Directory of Open Access Journals (Sweden)

    Carolina Freire de Carvalho Calabrich

    2010-08-01

    Full Text Available OBJETIVO: avaliar a atividade antimicrobiana da associação de um adesivo ortodôntico com um verniz de clorexidina e timol. MÉTODOS: foram utilizados 32 pré-molares humanos divididos em 4 grupos. O grupo 1 consistiu do grupo controle, no qual o adesivo utilizado para a colagem do braquete não estava associado a nenhum agente antimicrobiano. Os grupos 2, 3 e 4 foram colados com um sistema adesivo associado a um verniz de clorexidina e timol. Os grupos 3 e 4 foram armazenados em água por 7 dias e 30 dias, respectivamente, enquanto os corpos de prova do grupo 2 foram, logo depois da colagem, colocados em ágar semeado com Streptococcus mutans por 48h a 37ºC. RESULTADOS: os grupos experimentais, com exceção do grupo controle, apresentaram atividade antimicrobiana com tendência de redução do seu potencial de ação com maior tempo de imersão em água. CONCLUSÃO: a associação do verniz de clorexidina a um sistema adesivo utilizado em Ortodontia apresenta-se vantajosa pela sua atividade antimicrobiana.OBJECTIVE: To assess the antimicrobial activity resulting from the association of an orthodontic adhesive with chlorhexidine-thymol varnish. METHODS: Thirty-two extracted human premolars were used, divided into four groups. In Group 1, the control group, the adhesive used to bond the bracket was not associated with any antimicrobial agent. Groups 2, 3 and 4 were bonded with an adhesive system associated with chlorhexidine-thymol varnish. Groups 3 and 4 were stored in water for 7 days and 30 days, respectively, while the specimens from group 2 were, soon after bonding, placed on agar seeded with Streptococcus mutans for 48 hours, at 37º C. RESULTS: The experimental groups, with the exception of the control group, showed antimicrobial activity whose action tended to decline commensurately with the amount of time that they remained immersed in water. CONCLUSIONS: The association of chlorhexidine-thymol varnish with an adhesive system used in orthodontics proved to be advantageous due to its antimicrobial activity.

  2. Staining of esthetic brackets by plaque disclosing solutions

    Scientific Electronic Library Online (English)

    Luiza Novelino Acatauassú, Ismael; Mauro de Amorim Acatauassú, Nunes; Ana Maria Novelino Acatauassú, Nunes; Rogério Heládio Lopes, Motta; Ana Paula Dias, Demasi; Flávia Martão, Flório.

    2014-04-01

    Full Text Available AIM: To evaluate the staining of esthetic orthodontic brackets by plaque disclosing solutions. METHODS: Two types of brackets manufactured by GAC/DENTSPLY(r) were evaluated: ceramic (n=30) and polycarbonate (n=30). The brackets were divided into 6 groups. Two control groups (n=6) were immersed [...] in absolute ethanol: GI - ceramic brackets and GII - polycarbonate brackets. Four experimental groups (n=12) were immersed in different plaque disclosing solutions: GIII (ceramic brackets) and GIV (polycarbonate brackets) were immersed in Replak(r); GV (ceramic brackets) and GVI (polycarbonate brackets) were immersed in Replasul "S"(r). Relative quantitative analysis of the influence of plaque disclosing tablets on bracket staining was performed using reflectance spectrophotometry of stain deposition. Exploratory analysis of the data was performed using Analysis of Variance (ANOVA) in a 2x2 factorial setup (bracket x immersion) with additional treatments (controls). RESULTS: The results demonstrated that the ceramic brackets presented the highest amount of staining when Replasul "S"(r) was used (pd"0.05). However, when Replak(r) was used, no statistically significant difference was found in comparison with the control group (p>0.05). For polycarbonate brackets, staining was detected for both disclosing solutions (p>0.05). CONCLUSIONS: The disclosing solutions caused stain formation on polycarbonate brackets and, under the tested conditions, use of Replak(r) on ceramic brackets did not cause staining.

  3. Influência do tempo pós-fixação na resistência ao cisalhamento de bráquetes colados com diferentes materiais Influence of post-fixation time on shear bond strength of brackets fixed with different bonding materials

    Directory of Open Access Journals (Sweden)

    Lourenço CORRER SOBRINHO

    2002-03-01

    Full Text Available Este estudo avaliou a resistência ao cisalhamento da união, nos tempos pós-fixação de 10 minutos e 24 horas, de quatro materiais para colagem de bráquetes e os tipos de falhas na fratura. Foram utilizados 64 pré-molares humanos recém-extraídos embutidos em resina. As faces vestibulares de 32 pré-molares foram condicionadas com ácido fosfórico a 35%, por 30 segundos e em 16 deles, os bráquetes foram colados com Concise Ortodôntico (3M e nos demais com resina composta Z100 (3M. Em 32 dentes, os bráquetes foram colados sem condicionamento do esmalte, com ionômeros de vidro Fuji I (GC e Fuji Ortho LC (GC. Após a fixação, 32 corpos-de-prova foram armazenados em água destilada a 37ºC, por 10 minutos e o restante por 24 horas e submetidos ao teste de cisalhamento numa máquina com velocidade de 0,5 mm/min. Os resultados submetidos à ANOVA e ao teste de Tukey (5% mostraram que os maiores valores de resistência ao cisalhamento aos 10 minutos e 24 horas foram observados com o Concise Ortodôntico, com diferença estatística significativa em relação ao Fuji Ortho LC, Z100 e Fuji I. Nenhuma diferença estatística foi observada entre Fuji Ortho LC, Z100 e Fuji I. Os autores concluíram que o Concise Ortodôntico apresentou maiores valores de resistência ao cisalhamento em relação aos outros materiais, nos tempos de 10 minutos e 24 horas, os valores obtidos no período de 24 horas foram superiores em relação aos de 10 minutos, para todos materiais e um grande número de falhas adesivas foi observada para o Fuji I, Concise Ortodôntico e Z100.The purpose of this study was to evaluate the shear bond strength of four bonding materials for brackets, 10 minutes and 24 hours after their fixation, as well as the kinds of fracture observed. The buccal surfaces of 32 premolars were etched for 30 seconds with 35% phosphoric acid, and brackets were bonded using Orthodontic Concise (3M and Z100 (3M. In other 32 premolars, brackets were bonded with Fuji I (GC and Fuji Ortho LC (GC on the buccal surfaces, without acid etching. After the bonding procedures, 32 samples were stored in distilled water at 37ºC for 10 minutes, and 32 samples were stored at the same temperature for 24 hours. The samples were then submitted to shear bond strength testing in an Instron testing machine, at a crosshead speed of 0.5 mm/min. The results were submitted to ANOVA and Tukey’s test (p < 0.05. The results indicated that, for 10 minutes and 24 hours, Orthodontic Concise showed shear bond strength values (6.22 and 7.73 MPa, respectively higher than Fuji Ortho LC (3.32 and 5.10 MPa, Z100 (2.72 and 4.51 MPa and Fuji I (2.52 and 4.54 MPa. No statistical difference was verified between Fuji Ortho LC, Z100 and Fuji I (p < 0.05. In conclusion, Orthodontic Concise showed better shear bond strength values than the other three bonding materials, for both 10-minute and 24-hour storage periods; the shear bond strength averages were higher for the storage time of 24 hours, for all tested materials, and a great number of adhesive fractures were observed in the specimens which received Fuji I, Orthodontic Concise and Z100.

  4. A study on the frictional changes of steel bracket on the stainless steel wire during sliding

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    Shiva Alavi

    2010-01-01

    Full Text Available Introduction: Though sliding techniques are quite common in orthodontics, the produced friction however hampers ideal movement of teeth. Increased friction not only necessitates a greater orthodontic force but also results in anchorage loss. The aim of this study was to evaluate frictional changes of steel brackets on stainless steel wires while sliding. Materials and Methods: In this experimental study a total of 69 stainless steel brackets (Dentaurum with 0.018 inch slots were randomly divided into three groups of 23 brackets. With each group either 0.016 or 0.016 × 0.016 or 0.016 × 0.022 inch steel wires of the same company (Dentaurum were used in combination with brackets. There were 5 slots on each piece and every slot was 1mm apart from the next. Therefore each piece of wire was pulled via Dartec machine in every bracket slot with an average speed of 0.5mm/min in five sections. The amounts of friction were recorded. The collected data were then compared with repeated measurement ANOVA and paired sample T-test.(? = 0.05 Three brackets were randomly examined under scanning electron microscope (SEM at the beginning and after the first, the third and the fifth tractions.Results: Repeated measurement ANOVA showed statistical significant differences in static and kinetic frictions between first to fifth tractions in three sizes of wires. Based on paired sample t-test, significant differences were seen between first traction and the others. However, differences between the third and the forth, the third and the fifth and the forth and the fifth tractions were not significant between the three sizes of wires and the two kinds of frictions.Conclusion: It seems that friction would decrease during sliding of steel brackets on steel wires. Diameter and cross section of wires would have little effect on friction. Key words: Frictional changes, Sliding, Static friction, Kinetic friction.

  5. Improvement in adhesion of the brackets to the tooth by sandblasting treatment.

    Science.gov (United States)

    Espinar-Escalona, Eduardo; Barrera-Mora, José María; Llamas-Carreras, José María; Solano-Reina, Enrique; Rodríguez, D; Gil, F J

    2012-02-01

    In oral orthodontic treatments, achievement of a good adhesion between brackets and teeth surfaces is essential. One way to increase adhesion is to apply a surface treatment of teeth facing surfaces through the projection of abrasive particles to produce a surface roughness which improves adhesion of the bracket to the tooth, because of the significantly increased contact between the two surfaces. The effect on adhesion through the use of this technique in different types of brackets, as well as through the use of different blasting particles, however, is yet not well described. In this study we have included three types of brackets which are commonly used in orthodontic therapies (two of them a mesh-type and the third one a micro-milled type) with a contact surface area of 11.16, 8.85 and 6.89 mm(2) respectively. These brackets were used combined with a sandblasting treatment with two different types of abrasive particles, alumina (Al(2)O(3)) and silicon carbide (SiC) and applied to natural teeth in vitro. The abrasive particles used are bio-compatible and usually used in achieving increased roughness for improved adherence in biomedical materials. Sandblasting was performed at 2 bars for 2 s; three particle sizes were used: 80, 200 and 600 ?m. Non-blasted samples were used as control. Each of the pieces were cemented to natural teeth with a self-curing composite. Samples were stored in physiologic serum at 5°C temperature. Tensile tests were performed with a universal testing machine. Brackets treated with sandblasted particles were measured to have an increased adhesion as compared to the control sample. The highest bond strength was measured for samples sandblasted with alumina particles of 80 and 200 ?m combined with micro-milled brackets. The recorded stresses did not exceed the tensile strength of tooth enamel. PMID:22143910

  6. [Adult orthodontic technique: development and challenge].

    Science.gov (United States)

    Li, Song; Zhou, Jiemin; Ren, Chaochao

    2013-12-01

    Orthodontic treatments have increasingly become accepted by adults. However, the treatment therapies and philosophies for adults and adolescents have numerous differences. Orthodontic treatment for adults requires more careful planning, flexible management, interdisciplinary cooperation, and rational expectations. New techniques, such as mini-screw implants, invisalign, and self-ligating brackets, have recently been used to update treatments and widen the application of adult orthodontics by improving the treatment results. However, orthodontists still face a number of risks and challenges. PMID:24437283

  7. Avaliação da resistência ao cisalhamento de braquetes colados com resinas ortodônticas fluoretadas / Evaluation of shear bond strength of brackets bonded with orthodontic fluoride-releasing composite resins

    Scientific Electronic Library Online (English)

    Marcia Cristina, Rastelli; Ulisses, Coelho; Emígdio Enrique Orellana, Jimenez.

    2010-06-01

    Full Text Available OBJETIVO: avaliar a resistência ao cisalhamento de braquetes metálicos colados com resinas que contêm flúor, comparando-as a uma resina convencional; e analisar a quantidade de adesivo remanescente na superfície do esmalte. MÉTODOS: sessenta pré-molares foram divididos aleatoriamente em 3 grupos: Gr [...] upo I - Concise (3M), Grupo II - Ultrabond (Aditek do Brasil) e Grupo III - Rely-a-Bond (Reliance). Após a colagem dos braquetes, as amostras foram termocicladas (500 ciclos) nas temperaturas de 5°C e 55°C. Após 48 horas, foram submetidas aos ensaios mecânicos de cisalhamento na direção oclusocervical, com velocidade de carga de 0,5mm/min, em uma máquina MTS 810. RESULTADOS: foram observadas resistências médias ao cisalhamento de 24,54±6,98MPa para o Grupo I, de 11,53±6,20MPa para o Grupo II e de 16,46±5,72MPa para o Grupo III. A Análise de Variância determinou diferença estatística entre as médias de resistência ao cisalhamento entre os grupos (p Abstract in english OBJECTIVE: To evaluate the shear bond strength of stainless steel brackets bonded with fluoride releasing composite resins, comparing them with a conventional resin and to analyze the amount of resin left on the enamel surface. METHODS: Sixty premolars were randomly divided into three groups: Group [...] I - Concise (3M), Group II - Ultrabond (Aditek do Brasil) and Group III - Rely-a-Bond (Reliance). After bonding, the samples were thermocycled (500 cycles) at 5ºC and 55ºC temperatures. After 48 hours they were subjected to shear bond strength testing, in the occluso-gingival direction, using an MTS 810 Universal Testing Machine with load speed of 0.5 mm/min. RESULTS: The results demonstrated a mean shear bond strength of 24.54 ± 6.98 MPa for Group I, 11.53 ± 6.20 MPa for Group II, and 16.46 ± 5.72 MPa for Group III. Analysis of Variance (ANOVA) determined a statistical difference in the mean shear bond strengths between groups (p

  8. Comparison of frictional resistance of esthetic and semi-esthetic self-ligating brackets

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    M S Kannan

    2015-01-01

    Full Text Available Aim: The frictional resistance encountered during sliding mechanics has been well established in the orthodontic literature, and it consists of complex interactions between the bracket, archwire, and method of ligation the claim of reduced friction with self-ligating brackets is often cited as a primary advantage over conventional brackets. This study was done to compare and evaluate the frictional forces generated between fully esthetic brackets and semi-aesthetic self-ligating brackets, which are of passive form and SEM (scanning electron microscope study of the Brackets after Frictional evaluation. Materials and Methods: Two types of self-ligating esthetic brackets, Damon clear (Ormco made of fully ceramic and Opal (Ultradent Products, USA and, Two types of self-ligating semi-esthetic brackets, Clarity SL (3M Unitek and Damon 3 (Ormco both of which are made of ceramic with metal slot. Arch wires with different dimensions and quality 17 × 25, 19 × 25 Titanium Molybdenum Alloy (TMA and 17 × 25, 19 × 25 stainless steel that came from plain strands of wire were used for frictional comparison test. The brackets used in this study had 0.022 × 0.028 inch slot. Results: The statistical tests showed significantly smaller amount of kinetic frictional forces is generated by Damon 3 (semi-esthetic self-ligating brackets. For each wire used, Damon 3 displayed significantly lower frictional forces (P ≤ 0.05 than any of the self-ligating system, followed by Opal (fully esthetic self-ligating brackets which generated smaller amount of frictional forces but relatively on the higher side when compared with Damon 3. Damon clear (fully esthetic self-ligating brackets generated the maximum amount of kinetic forces with all types of wire dimensions and properties when compared to the other three types of self-ligating system. Clarity SL (semi-esthetic self-ligating brackets generated smaller amount of frictional forces when compared with Damon clear and relatively higher amount of frictional forces when compared to Opal and Damon 3

  9. Antimicrobial and fluoride release capacity of orthodontic bonding materials

    Scientific Electronic Library Online (English)

    Erika Machado, Caldeira; Amanda, Osorio; Edna Lucia Couto, Oberosler; Delmo Santiago, Vaitsman; Daniela Sales, Alviano; Matilde da Cunha Goncalves, Nojima.

    2013-07-01

    Full Text Available OBJECTIVE: The aim of this study was to evaluate the antimicrobial and fluoride releasing capacity of 3 bonding materials. MATERIAL AND METHODS: Thirty nine specimens with standardized surface smoothness and dimensions were prepared. The antimicrobial capacity of the materials against S. mutans, [...] L. casei and C. albicans was evaluated by determining the percentage of growth inhibition of these microorganisms in an inoculated medium, obtained by optical density readouts on a spectrophotometer. The potential to interfere in microbial growth on the surface of the studied materials was observed by means of scanning electron microscopy (SEM). The fluoride release capacity in ultrapure water for 14 days was analyzed by means of ion chromatography. RESULTS: The PLUS group presented the highest percentage of microbial inhibition and the most contamination-free surface. The FUJI group presented the best fluoride release capacity. CONCLUSIONS: The TransbondTM Plus Color Change was the one that presented the best general behavior considering the evaluated aspects.

  10. An innovative approach for investigating the ceramic bracket-enamel interface - optical coherence tomography and confocal microscopy

    Science.gov (United States)

    Romînu, Roxana Otilia; Sinescu, Cosmin; Romînu, Mihai; Negrutiu, Meda; Laissue, Philippe; Mihali, Sorin; Cuc, Lavinia; Hughes, Michael; Bradu, Adrian; Podoleanu, Adrian

    2008-09-01

    Bonding has become a routine procedure in several dental specialties - from prosthodontics to conservative dentistry and even orthodontics. In many of these fields it is important to be able to investigate the bonded interfaces to assess their quality. All currently employed investigative methods are invasive, meaning that samples are destroyed in the testing procedure and cannot be used again. We have investigated the interface between human enamel and bonded ceramic brackets non-invasively, introducing a combination of new investigative methods - optical coherence tomography (OCT) and confocal microscopy (CM). Brackets were conventionally bonded on conditioned buccal surfaces of teeth The bonding was assessed using these methods. Three dimensional reconstructions of the detected material defects were developed using manual and semi-automatic segmentation. The results clearly prove that OCT and CM are useful in orthodontic bonding investigations.

  11. DAS?s incisal and occlusal window transfer tray for indirect bonding in lingual orthodontics

    Directory of Open Access Journals (Sweden)

    Surya Kanta Das

    2013-01-01

    Full Text Available This bracket transfer tray is so designed in such a way that the excess composite flash during indirect bracket bonding is pushed in the incisal and occlusal direction only so that it can easily be removed by rotary instruments. In lingual orthodontics, where accessing the gingival and interdental areas with rotary instruments is very difficult, this transfer tray system is helpful for easy flash removal and simple clinical maneuver. Additional silicon putty material is used to make this tray that has a palatal strip, a labial/bucal strip with incisal and occlusal stops and interbracket connectors.

  12. Analysis of mesiodistal angulations of preadjusted brackets

    Scientific Electronic Library Online (English)

    Marcos Rogério de, MENDONÇA; Ana Caroline Gonçales, VERRI; Aubrey Fernando, FABRE; Osmar Aparecido, CUOGHI.

    2014-08-21

    Full Text Available Manufacturers offer various prescriptions of preadjusted brackets for use in the “straight-wire” orthodontic technique. However, the need to incorporate bends in the rectangular wires during orthodontic finishing has led to concerns regarding the type of prescription chosen and the credibility of in [...] formation provided by the manufacturer. The aim of this study was to compare the slot angulations of Roth prescription preadjusted metallic brackets for the maxillary left central incisor and maxillary left canine. For each tooth type, 10 brackets of three commercial brands (GAC, Forestadent and Morelli) were selected. Two individual metal matrices for brackets and tooth positioning were made for each group of teeth. Captured images were obtained by standardized ortho-radial photography with a digital camera. Images were exported and analyzed with the Image J software package. One-way ANOVA and Tukey statistical analyses were performed at the 5% significance level. For brackets of the maxillary left central incisor, differences in mean angulation were observed between the Morelli and GAC groups (p

  13. Potential application of shape memory plastic as elastic material in clinical orthodontics.

    Science.gov (United States)

    Nakasima, A; Hu, J R; Ichinose, M; Shimada, H

    1991-06-01

    Polynorbornen, a shape memory plastic developed in Japan, has a glass transitional point of 35 degrees C. Once the environmental temperature exceeds the critical point, this plastic will begin to display an elastic property, then return to its original shape, if deformed. We examined whether the force generated during the elastic phase of polynorbornen could be used to displace human teeth. We found that the shape memory plastic wire of 1 mm in diameter stretched to two to three times of its original length at a temperature of 50 degrees C and a speed of 0.5 mm/sec would exert a relatively stable continuous light force of 119-156 g to move the teeth. This new material, compared with conventional elastic modules used in orthodontic therapy, exhibited a lesser degree of force degradation at a body temperature of 37 degrees C for a long period, and can be manufactured to near the tooth colour required. These advantages make feasible clinical application of the shape memory plastic in orthodontics. PMID:1936135

  14. Influence of lingual bracket position on microbial and periodontal parameters in vivo

    Directory of Open Access Journals (Sweden)

    Maria Francesca Sfondrini

    2012-06-01

    Full Text Available OBJECTIVE: Lingual orthodontics is becoming more popular in dental practice. The purpose of the present investigation was to compare plaque formation on teeth bonded with the same bracket onto buccal or lingual surface, with non-bonded control teeth, via an in vivo growth experiment over a 30-day period. MATERIAL AND METHODS: A randomized controlled trial with split-mouth design was set up enrolling 20 dental students. Within each subject sites with buccal and lingual brackets and control sites were followed. Clinical periodontal parameters (periodontal pocket depth: PPD; bleeding on probing: BOP were recorded at baseline and on days 1, 7 and 30. Microbiological samples were taken from the brackets and the teeth on days 1, 7 and 30 to detect colony-forming units (CFU. Total CFU, streptococci CFU and anaerobe CFU were measured. RESULTS: No significant differences (P>0.05 were found between buccal and lingual brackets in terms of clinical periodontal parameters and microbiological values. Conclusion: Bracket position does not have significant impact on bacterial load and on periodontal parameters.

  15. Experiense with remineraling means in patients undergoing orthodontic treatment

    Directory of Open Access Journals (Sweden)

    Stepanova Ye.A.

    2011-03-01

    Full Text Available In patients undergoing orthodontic treatment using bracket-technology a high risk of caries development. The algorithm of preventive interventions for the prevention of hair demineralization of enamel of the teeth

  16. Comparison of static friction with self-ligating, modified slot design and conventional brackets

    Scientific Electronic Library Online (English)

    Raquel Morais, Castro; Perrin, Smith Neto; Martinho Campolina Rebello, Horta; Matheus Melo, Pithon; Dauro Douglas, Oliveira.

    2013-07-01

    Full Text Available OBJECTIVE: To compare the static frictional forces generated at the bracket/wire interface of stainless steel brackets with different geometries and angulations, combined with orthodontic wires of different diameters. MATERIAL AND METHODS: The frictional forces were evaluated with three differe [...] nt types of metal brackets: a passive self-ligating (SmartClipTM, 3M/Unitek, Monrovia, USA), with a modified slot design (Mini Uni TwinTM, 3M/Unitek, Monrovia, USA) and conventional (Kirium, Abzil, São José do Rio Preto, Brazil). The samples were mounted in a testing device with three different angulations and tested with 0.014" and 0.018" stainless steel wires (American Orthodontics, Sheboygan, USA). The static frictional force was measured using a universal testing machine (DL 500, EMIC®, São José dos Pinhais, Brazil) with a crosshead speed of 1 mm/min. Statistical analysis was performed by two-way ANOVA followed by Bonferroni's post hoc test. RESULTS: There was a significant difference (p

  17. Rapid orthodontics

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    A Bhagyalakshmi

    2012-01-01

    Full Text Available Every orthodontic patient requires that the treatment be completed in a short duration. During orthodontic treatment, wearing of orthodontic braces, besides being unaesthetic will also restrict patients from eating certain food; it would also make it difficult for patient to maintain good oral hygiene. Because of these reasons many patients decline for orthodontic treatment. But recently there are many techniques in orthodontics like distraction osteogenesis, corticotomy, etc. where treatment can be completed in a very short duration when compared to conventional treatment. This article discusses one of such technique known as "Wilkodontics" which helps in faster orthodontic tooth movement, thus helping the clinician to complete the treatment at the earliest.

  18. Clinical comparison between a modified light-curing denture base resin and a conventional composite resin for orthodontic bonding.

    Science.gov (United States)

    Rizzo, Lucia; Cacciafesta, Vittorio; Melsen, Birte

    2003-01-01

    The purpose of this in vivo study was to evaluate and compare the bond failure rate of a modified visible light-cured denture base resin (Triad VLC Provisional Material; Dentsply International Inc., York, PA) with that of a conventional visible light-cured composite resin (Transbond XT; 3M/Unitek, Monrovia, CA) for the bonding of orthodontic brackets. Both adhesives were used in each patient following a split-mouth design. Thirty-five consecutive patients with fixed appliances were included in the study, and the performance of 655 stainless steel brackets was evaluated: 325 brackets were bonded with the modified Triad VLC resin and 330 were bonded with Transbond XT resin. The incidence and site of bond failures were recorded over a period of 12 months. The overall failure rate of Triad VLC (4.3%) was not significantly different (p>0.05) from that of Transbond XT (3.6%). No significant differences in the failure rates of upper and lower arches within each material or between the two materials were found (p>0.05). Transbond XT showed a significantly higher failure rate (pmaterial for direct bonding of orthodontic brackets. PMID:12887574

  19. Motivational Goal Bracketing

    DEFF Research Database (Denmark)

    Nafziger, Julia; Koch, Alexander

    It is a puzzle why people often evaluate consequences of choices separately (narrow bracketing) rather than jointly (broad bracketing). We study the hypothesis that a present-biased individual, who faces two tasks, may bracket his goals narrowly for motivational reasons. Goals motivate because they...... tasks. Narrow goals have a stronger motivational force and thus can be optimal. In particular, if one task outcome becomes known before working on the second task, narrow bracketing is always optimal....

  20. Fixed orthodontic appliances cause pain and disturbance in somatosensory function

    DEFF Research Database (Denmark)

    Shen, Huijie; Shao, Sheng; Zhang, Jinglu; Wang, Zhendong; Lv, Dong; Chen, Wenjing; Svensson, Peter; Wang, Kelun

    2016-01-01

    This study aimed to assess the short-term effects of orthodontic pain on quantitative sensory testing (QST) in subjects receiving fixed orthodontic treatment. Twenty patients and 12 healthy volunteers (as controls) participated. All 20 patients had bonded AO self-ligating brackets, with a 0...... results suggest clear signs of sensitization of the trigeminal nociceptive system up to 1 month after force application and orthodontic pain. Quantitative assessment of somatosensory function may help to provide a better understanding and profiling of the underlying neurobiological mechanisms related to...... orthodontic pain....

  1. Avaliação da resistência à tração de artifícios ortodônticos - braquete, botão e tela - colados em pré-molares com resina autopolimerizável. estudo "in vitro" / Evaluation of the resistance to traction of orthodontic devices - bracket, bouton and frame - bonded in premolar with autopolimerizable resin. "in vitro" study

    Scientific Electronic Library Online (English)

    Walter Leal de, Moura; Thaís Cristina Araújo, Moreira; João Batista Mendes, Teles.

    2004-06-01

    Full Text Available Retenção dentária é a condição fisiopatológica em que o dente, uma vez chegado o seu momento fisiológico de erupção, apresenta algum impedimento para realizá-lo. O tratamento, com envolvimento cirúrgico-ortodôntico, visa deslocar o elemento dental para a correta posição na arcada dentária, sem causa [...] r danos aos elementos dentais adjacentes, restabelecendo a estética e a função. A colagem direta de botões e braquetes ortodônticos para tração de dentes inclusos transformou-se na técnica preferida, pois exige menor extensão cirúrgica e remoção de tecido para acesso à coroa dental. A pesquisa objetivou analisar a intensidade da força aplicada ao conjunto dente/artifício/fio de amarrilho, pelo tracionamento, e observar o local do rompimento. Utilizaram-se 45 pré-molares, conservados em soro fisiológico 0,9%, que foram divididos em 3 grupos (15 com braquetes, 15 com botões e 15 com telas). Os dentes foram fixados em canos de PVC preenchidos com resina acrílica e os acessórios fixados ao dente com resina autopolimerizável. Após a colagem dos acessórios ortodônticos, os dentes voltaram a ser conservados em soro fisiológico e o teste realizado após 72 horas, com a utilização de um sensor de força e um programa de computador (Logger Pro). Com os resultados, observou-se que o braquete resistiu a uma força média de 36,0N, sendo a junção fio/braquete o local menos resistente; o botão resistiu a uma força média de 41,2N, a junção fio/botão ortodôntico foi o local menos resistente e a tela resistiu a uma força média de 28,8N, sendo a junção dente/tela o local menos resistente. Abstract in english Restrained is the tooth which, reached its physiological moment of eruption, shows some obstruction to accomplish it. The treatment, with orthodontic-surgical involvement, type drives at to dislocate the dental element for right position in the dental arch, without to cause damages for adjacent dent [...] al element, re-establishing the aesthetics and function. Therefore, the direct bonding of orthodontic bracket and bouton for retained teeth traction became the preferred technic for, besides more clear, it demands smaller surgical amplitude and tissue removal to grant access to the dental crown. The research intended analyse the intensity of applied force to the entirety teeth/device/tie-wire, tractioning through, and to observe the splot rupture. Maked use of 45 premolar, conserved in 0.9%¹ physiological serum, that was divided into three groups (15 with brackets, 15 with boutons and 15 with frames). The tooth was filled in PVC pipe filled with acrylic resin and the devices was bonded to the teeth with autopolimerizable resin. After the bonding realization of the orthodontic devices, the tooth was be preserved in physiological serum and the tests was be realized after 72 hours of the bonding by means of a computer program. The bracket endured to medium force of 36,0N, being the junction wire-device the spot less resistant; the bouton endured to medium force of 41,2N, the juncion wire-bouton was the plot less resistant and the frame was endured to medium force of 28,8N, being the junction teeth/frame the plot less resistant.

  2. Avaliação da resistência à tração de artifícios ortodônticos - braquete, botão e tela - colados em pré-molares com resina autopolimerizável. estudo "in vitro" Evaluation of the resistance to traction of orthodontic devices - bracket, bouton and frame - bonded in premolar with autopolimerizable resin. "in vitro" study

    Directory of Open Access Journals (Sweden)

    Walter Leal de Moura

    2004-06-01

    Full Text Available Retenção dentária é a condição fisiopatológica em que o dente, uma vez chegado o seu momento fisiológico de erupção, apresenta algum impedimento para realizá-lo. O tratamento, com envolvimento cirúrgico-ortodôntico, visa deslocar o elemento dental para a correta posição na arcada dentária, sem causar danos aos elementos dentais adjacentes, restabelecendo a estética e a função. A colagem direta de botões e braquetes ortodônticos para tração de dentes inclusos transformou-se na técnica preferida, pois exige menor extensão cirúrgica e remoção de tecido para acesso à coroa dental. A pesquisa objetivou analisar a intensidade da força aplicada ao conjunto dente/artifício/fio de amarrilho, pelo tracionamento, e observar o local do rompimento. Utilizaram-se 45 pré-molares, conservados em soro fisiológico 0,9%, que foram divididos em 3 grupos (15 com braquetes, 15 com botões e 15 com telas. Os dentes foram fixados em canos de PVC preenchidos com resina acrílica e os acessórios fixados ao dente com resina autopolimerizável. Após a colagem dos acessórios ortodônticos, os dentes voltaram a ser conservados em soro fisiológico e o teste realizado após 72 horas, com a utilização de um sensor de força e um programa de computador (Logger Pro. Com os resultados, observou-se que o braquete resistiu a uma força média de 36,0N, sendo a junção fio/braquete o local menos resistente; o botão resistiu a uma força média de 41,2N, a junção fio/botão ortodôntico foi o local menos resistente e a tela resistiu a uma força média de 28,8N, sendo a junção dente/tela o local menos resistente.Restrained is the tooth which, reached its physiological moment of eruption, shows some obstruction to accomplish it. The treatment, with orthodontic-surgical involvement, type drives at to dislocate the dental element for right position in the dental arch, without to cause damages for adjacent dental element, re-establishing the aesthetics and function. Therefore, the direct bonding of orthodontic bracket and bouton for retained teeth traction became the preferred technic for, besides more clear, it demands smaller surgical amplitude and tissue removal to grant access to the dental crown. The research intended analyse the intensity of applied force to the entirety teeth/device/tie-wire, tractioning through, and to observe the splot rupture. Maked use of 45 premolar, conserved in 0.9%¹ physiological serum, that was divided into three groups (15 with brackets, 15 with boutons and 15 with frames. The tooth was filled in PVC pipe filled with acrylic resin and the devices was bonded to the teeth with autopolimerizable resin. After the bonding realization of the orthodontic devices, the tooth was be preserved in physiological serum and the tests was be realized after 72 hours of the bonding by means of a computer program. The bracket endured to medium force of 36,0N, being the junction wire-device the spot less resistant; the bouton endured to medium force of 41,2N, the juncion wire-bouton was the plot less resistant and the frame was endured to medium force of 28,8N, being the junction teeth/frame the plot less resistant.

  3. Orthodontic forces generated by a simulated archwire appliance evaluated by the finite element method.

    Science.gov (United States)

    Fotos, P G; Spyrakos, C C; Bernard, D O

    1990-01-01

    The finite element method has been used to determine the stress distribution generated by the initial placement of a simulated preset bracket-type orthodontic appliance utilizing titanium-nickel alloy archwire. PMID:2256565

  4. Effectiveness of Mouth Washes on Streptococci in Plaque around Orthodontic Appliances.

    Science.gov (United States)

    Fard, Behnam Khosravani; Ghasemi, Mahmood; Rastgariyan, Hossein; Sajjadi, Seyed Hadi; Emami, Houshang; Amani, Masoomeh; Motamedi, Mohammad Hosein Kalantar

    2011-01-01

    Background and Purpose. Fixed orthodontics may be associated with accumulation of Mutans Streptococci (MS), enamel demineralization, and an increased number of carious lesions, predominantly in sites adjacent to brackets. This study was undertaken to assess the effectiveness of Listerine, Oral-B, and Ortho-kin on the accumulation of MS in plaque around orthodontic brackets. Materials and Methods A double-blind randomized cross-over clinical trial on 25 orthodontic patients, classified into 6 groups was done to assess MS in plaque and saliva with the side specific modified Strip-Mutans technique and the plaque (PI) was measured before and after rinsing using 3 types of commercial mouth-rinses. A washout period (3 weeks) was awaited between using each mouth-rinse and the data was analyzed via Wilcoxon and Kruskal Wallis statistical tests. Results. This study of 25 patients, 5 men and 20 women, with an average age of 19 ± 6/3 assessed the effectiveness of mouth-rinses on MS. Our results showed that Ortho-kin had a better effect than Oral-B and Listerine (P Listerine on plaque accumulation (P < 0/001). Conclusion. Ortho-kin showed better effects on decreasing MS and PI because it contained chlorhexidine. PMID:21991490

  5. Frictional Resistance of Three Types of Ceramic Brackets

    Directory of Open Access Journals (Sweden)

    Claire L Williams

    2014-01-01

    Full Text Available Objectives: To investigate the static frictional resistance at the bracket/archwire interface in two recently introduced bracket systems and compare them to conventional ceramic and conventional metal bracket systems. Three variables were considered including the bracket system, archwire type and archwire angulation. Material and Methods: Four bracket systems were tested in vitro: Self ligating ceramic, ceramic with metal slot and module, conventional ceramic with module and conventional metal with module. A specially constructed jig and an Instron testing machine were used to measure the static frictional resistance for 0.014 inches round and 0.018 x 0.025 inches rectangular stainless steel wires at 0° and 7° angulations. Main outcome measures: static frictional force at the bracket/archwire interface; recorded and measured in units of force (Newtons. Results: Self ligating ceramic and metal slot ceramic bracket systems generated significantly less static frictional resistance than conventional ceramic bracket systems with the wire at both angulations (P < 0.05. Changing the wire from 0.014 round to 0.018 x 0.025 rectangular wire significantly increased frictional forces for metal slot ceramic and conventional metal bracket systems (P < 0.01. Increasing wire angulation significantly increased frictional resistance at the bracket/archwire interface for all four types of bracket systems tested (P < 0.001. Conclusions: Compared to conventional ceramic, self ligating ceramic and metal slot ceramic bracket systems should give improved clinical performance, matching that of conventional metal brackets.

  6. Force loss in archwire-guided tooth movement of conventional and self-ligating brackets.

    Science.gov (United States)

    Montasser, Mona A; El-Bialy, Tarek; Keilig, Ludger; Reimann, Susanne; Jäger, Andreas; Bourauel, Christoph

    2014-02-01

    This study aimed to investigate the differences in the force loss during simulated archwire-guided canine retraction between various conventional and self-ligating brackets. Three types of orthodontic brackets have been investigated experimentally using a biomechanical set-up: 1. conventional ligating brackets (Victory Series and Mini-Taurus), 2. self-ligating brackets (SmartClip: passive self-ligating bracket, and Time3 and SPEED: active self-ligating brackets), and 3. a conventional low-friction bracket (Synergy). All brackets had a nominal 0.022? slot size. The brackets were combined with three rectangular 0.019×0.025? archwires: 1. Remanium (stainless steel), 2. Nitinol SE (nickel-titanium alloy, NiTi), and 3. Beta III Titanium (titanium-molybdenum alloy). Stainless steel ligatures were used with the conventional brackets. Archwire-guided tooth movement was simulated over a retraction path of up to 4mm using a superelastic NiTi coil spring (force: 1 N). Force loss was lowest for the Victory Series and SmartClip brackets in combination with the steel guiding archwire (35 and 37.6 per cent, respectively) and highest for the SPEED and Mini-Taurus brackets in combination with the titanium wire (73.7 and 64.4 per cent, respectively). Force loss gradually increased by 10 per cent for each bracket type in combination with the different wires in the following sequence: stainless steel, Nitinol, and beta-titanium. Self-ligating brackets did not show improved performance compared with conventional brackets. There was no consistent pattern of force loss when comparing conventional and self-ligating brackets or passive and active self-ligating brackets. PMID:23382468

  7. A study in vitro on radiation effects by Er:YAG laser combined with the fluorine therapy in the acid resistance of the dental enamel submitted to orthodontical brackets; Um estudo in vitro sobre os efeitos da irradiacao pelo laser de Er:YAG combinado com a terapia com fluor na resistencia acida do esmalte de dentes submetidos a aparelho ortodontico fixo

    Energy Technology Data Exchange (ETDEWEB)

    Yoshiyasu, Roseli Y.A

    2001-07-01

    Several researches have been demonstrating an increase in the resistance acid of the enamel surface when irradiated by some lasers types as Nd:YAG, C0{sub 2}, Er:YAG, and others, mainly when combined with the fluoride therapy after the irradiation of the laser. This study in vitro used the laser of Er:YAG which density of energy of 8.1 J/cm{sup 2} on the enamel about of orthodontical brackets of teeth extracted pre-molars. These teeth were then submitted to a rich way in S. mutans for twenty one days. The cases were analyzed: (1) enamel surface without any treatment, (2) enamel surface without any irradiation laser, but with therapy with acidulated phosphate fluoride, (3) enamel surface irradiated with laser of Er:YAG and (4) enamel surface irradiated by laser of Er:YAG and with application of acidulated phosphate fluoride. The results were analyzed through optical microscopy and scanning electron microscopy. The morphologic changes observed to the scanning electron microscopy suggest increase in the acid resistance of the enamel surface. However, to the optical microscopy, it was still possible to visualize undesirable white stains in the surface of the enamel. (author)

  8. Generalized Moshinsky bracket recurrence relations

    International Nuclear Information System (INIS)

    Recurrence relations for generalized Talmi-Moshinsky brackets are derived. These relations permit the generation of transformation brackets once appropriate starting brackets are determined. The savings in computer time, when compared with generating brackets individually, is at least a factor of 10 for brackets with radial quantum numbers as large as 9 and angular quantum numbers as large as 2. (author)

  9. Nd:YAG Laser-aided ceramic brackets debonding: Effects on shear bond strength and enamel surface

    Energy Technology Data Exchange (ETDEWEB)

    Han Xianglong [State Key Laboratory of Oral Diseases, Sichuan University, Chengdu 610041 (China); Department of Orthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu 610041 (China); Liu Xiaolin [Department of Orthodontics, Stomatology Hospital, Dalian University, Dalian 116021 (China); Bai Ding [State Key Laboratory of Oral Diseases, Sichuan University, Chengdu 610041 (China); Department of Orthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu 610041 (China)], E-mail: baiding88@hotmail.com; Meng Yao; Huang Lan [Department of Orthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu 610041 (China)

    2008-11-15

    In order to evaluate the efficiency of Nd:YAG laser-aided ceramic brackets debonding technique, both ceramic brackets and metallic brackets were bonded with orthodontic adhesive to 30 freshly extracted premolars. The specimens were divided into three groups, 10 in each, according to the brackets employed and the debonding techniques used: (1) metallic brackets with shear debonding force, (2) ceramic brackets with shear debonding force, and (3) ceramic brackets with Nd:YAG laser irradiation. The result showed that laser irradiation could diminish shear bond strength (SBS) significantly and produce the most desired ARI scores. Moreover, scanning electron microscopy investigation displayed that laser-aided technique induced little enamel scratch or loss. It was concluded that Nd:YAG laser could facilitate the debonding of ceramic brackets and diminish the amount of remnant adhesive without damaging enamel structure.

  10. Shear bond strength of metallic and ceramic brackets using color change adhesives

    Scientific Electronic Library Online (English)

    Aisha de Souza Gomes, Stumpf; Carlos, Bergmann; José Renato, Prietsch; Juliane, Vicenzi.

    2013-04-01

    Full Text Available OBJETIVO: determinar a resistência adesiva à tração de braquetes ortodônticos usando resinas coloridas que se propõem a ajudar na remoção do excesso de material adesivo e compará-las com um adesivo tradicional. MÉTODOS: Noventa braquetes metálicos e 90 cerâmicos foram colados com dois adesivos color [...] idos e com um adesivo tradicional em incisivos inferiores bovinos, sendo aplicada tração com uma máquina de ensaios universal. Após a descolagem, os dentes foram observados em microscópio para a determinação do índice de adesivo remanescente (ARI). RESULTADOS: a análise estatística (testes ANOVA, de Tukey e de Kruskall-Wallis) demonstrou que a força de união média foi significativa entre os adesivos usados. Os ARIs mais comuns foram aqueles onde o adesivo permaneceu no esmalte. CONCLUSÃO: a resistência adesiva foi similar entre braquetes metálicos e cerâmicos quando o mesmo adesivo foi usado. Os resultados do ARI demonstraram que esses adesivos são seguros, mesmo com o uso de braquetes cerâmicos. A resistência adesiva foi muito baixa para Ortodontia no grupo colado com Ortho Lite Cure. Abstract in english OBJECTIVE: To determine the shear bond strength of orthodontic brackets using color change adhesives that are supposed to aid in removing excess of bonding material and compare them to a traditional adhesive. METHODS: Ninety metallic and ninety ceramic brackets were bonded to bovine incisors using t [...] wo color change adhesives and a regular one. A tensile stress was applied by a universal testing machine. The teeth were observed in a microscope after debonding in order to determine the Adhesive Remnant Index (ARI). RESULTS: The statistical analysis (ANOVA, Tukey, and Kruskall-Wallis tests) demonstrated that the mean bond strength presented no difference when metallic and ceramic brackets were compared but the bond resistance values were significantly different for the three adhesives used. The most common ARI outcome was the entire adhesive remaining on the enamel. CONCLUSIONS: The bond strength was similar for metallic and ceramic brackets when the same adhesive system was used. ARI scores demonstrated that bonding with these adhesives is safe even when ceramic brackets were used. On the other hand, bond strength was too low for orthodontic purposes when Ortho Lite Cure was used.

  11. Bond strength of different bracket bonding materials to the enamel subjected to thermal cycling / Resistência de união de diferentes materiais de colagem de bráquetes ao esmalte submetidos à ciclagem térmica

    Scientific Electronic Library Online (English)

    Alcir, ROSOLEN; Enrico Coser, BRIDI; Roberta Tarkany, BASTING.

    2015-03-01

    Full Text Available OBJETIVO: Avaliar in vitro a resistência de união por cisalhamento de bráquetes ortodônticos metálicos ao esmalte utilizando diferentes materiais para colagem em função da quantidade de ciclos térmicos. MÉTODOS: Foram avaliados um sistema de união com resina composta fluida (Transbond XT/3M Unitek) [...] e um ionômero de vidro modificado por resina (Fuji Ortho LC/GC America Inc.). Oitenta pré-molares humanos hígidos foram aleatoriamente divididos em oito grupos experimentais (n=10), de acordo com os tipos de material e quantidade de ciclos térmicos: zero, 1000, 2000 e 3000 ciclos. A colagem dos bráquetes foi realizada na face vestibular dos dentes. Após 24 horas, foram submetidos à ciclagem térmica com temperaturas de imersão entre 5ºC e 55ºC por 15 segundos. Os testes de resistência de união foram feitos em máquina de ensaios universal com ponta tipo cinzel com velocidade de 0,5 mm/min. Os dados foram submetidos à ANOVA a dois critérios. RESULTADOS: Não houve diferença na resistência de união entre bráquetes e o esmalte em função do número de ciclos térmicos (p = 0,873). Houve diferença significativa na resistência de união proporcionada entre os materiais para colagem (p = 0,022), sendo que valores significativamente superiores foram obtidos com a utilização do Transbond XT, independentemente do número de ciclos térmicos. CONCLUSÃO: A quantidade de ciclos térmicos não influenciou significativamente a resistência de união dos materiais. Transbond XT mostrou maior resistência de união do que o cimento Fuji Ortho LC, independentemente da quantidade de ciclos térmicos. Abstract in english OBJECTIVE: The aim of this study was to evaluate in vitro the shear bond strength of metallic orthodontic brackets to enamel using different bonding materials followed by thermal cycling. METHODS: A fluid composite resin (Transbond XT / 3M Unitek) and a resin-modified glass ionomer (Fuji Ortho LC / [...] GC America Inc.) were evaluated. Eighty sound human premolars were randomly divided into eight experimental groups (n = 10), according to the material used and the number of thermal cycles: zero, 1000, 2000 and 3000 cycles. Bracket bonding was performed on the buccal surface of the teeth. After 24 hours, they were subjected to thermal cycling at temperatures ranging between 5° C and 55° C for 15 seconds each immersion. Shear bond strength was performed using a universal testing machine with a chisel-type tip at a speed of 0.5 mm / min. The bond strength data was analyzed using two-way ANOVA. RESULTS: No difference on shear bond strength was observed regarding the number of thermal cycles for each specimen (p = 0.873). A significant difference was found in shear bond strength between the bonding materials (p = 0.022), with significantly higher values for Transbond XT regardless of the number of thermal cycles. CONCLUSION: The number of thermal cycles did not significantly affect the bond strength of the adhesive materials investigated. The bonding agent Transbond XT showed higher bond strength than Fuji Ortho LC regardless of the number of thermal cycles.

  12. Using Little's Irregularity Index in orthodontics: outdated and inaccurate?

    LENUS (Irish Health Repository)

    Macauley, Donal

    2012-12-01

    Little\\'s Irregularity Index (LII) was devised to objectively score mandibular incisor alignment for epidemiological studies but has been extended to assess the relative performance of orthodontic brackets, retainer or treatment modalities. Our aim was to examine the repeatability and precision of LII measurements of four independent examiners on the maxillary arch of orthodontic patients. The hypothesis was that the reproducibility of individual contact point displacement measurements, used to calculate the LII score, are inappropriate.

  13. DESIGN OPTIMIZATION OF TORQUE ARM BRACKET

    Directory of Open Access Journals (Sweden)

    Pankaj D. Shende

    2014-11-01

    Full Text Available The focus of this project is to investigate how a crack propagates and grows in a typical direction of Torque arm bracket. The finite element program and the crack growth program will be used to simulate crack growth and to compute the stresses and the stress-intensity factor. Aspecific bracket design was selected and a corner crack was investigated. This configuration was used since the engineers often detect this type of crack in brackets. The stress near the crack tip is compared against the yield strength of the material. The Mode I stress-intensity factor is compared against the material’s fracture toughness. The results show that the bracket can tolerate small cracks in the structure. The fatigue strength of the structure is recommended to be assessed in the future.

  14. Effect of Adhesive Type on the Shear Bond Strength of Metal Brackets to Two Ceramic Substrates

    Directory of Open Access Journals (Sweden)

    Mohammad Sadegh Ahmad Akhoundi

    2014-04-01

    Full Text Available Increased number of adult patients requesting orthodontic treatment result in bonding bracket to ceramic restorations more than before. The aim of this study was to evaluate and compare the shear bond strength of orthodontic brackets bonded to two types of ceramic bases with conventional orthodontic bonding resin and a new nano-filled composite resin.Twenty four feldespathic porcelain and 24 lithium disilicate ceramic disks were fabricated. All of the samples were conditioned by sandblasting, hydrofluoric acid and silane. Maxillary incisor metal brackets were bonded to half of the disks in each group by conventional orthodontic bonding resin and the other half bonded with a nano-filled composite. The samples then were thermocycled for 2000 cycle between 5-55° C. Shear bond strength was measured and the mode of failure was examined. Randomly selected samples were also evaluated by SEM.The lowest bond strength value was found infeldespathic ceramic bonded by nano-filled composite (p<0.05. There was not any statistically significant difference between other groups regarding bond strength. The mode of failure in the all groups except group 1 was cohesive and porcelain damages were detected.Since less damages to feldspathic porcelain was observed when the nano-filled composite was used to bond brackets, the use of nano-filled composite resins can be suggested for bonding brackets to feldspathic porcelain restorations.

  15. Improvement in adhesion of the brackets to the tooth by sandblasting treatment

    OpenAIRE

    Espinar, Eduardo; J. Barrera; Llamas, José María; Solano, E.; Rodríguez Rius, Daniel; Gil Mur, Francisco Javier

    2011-01-01

    In oral orthodontic treatments, achievement of a good adhesion between brackets and teeth surfaces is essential. One way to increase adhesion is to apply a surface treatment of teeth facing surfaces through the projection of abrasive particles to produce a surface roughness which improves adhesion of the bracket to the tooth, because of the significantly increased contact between the two surfaces. The effect on adhesion through the use of this technique in different ty...

  16. Adjunctive orthodontic treatment with lingual orthodontic system.

    Science.gov (United States)

    Kafle, D; Humagain, M; Upadhaya, C

    2011-01-01

    The lingual orthodontic therapy though started in 1972, could not be popular till the beginning of 1990. In Nepal it does not have a history of more than a year. It is started in Dhulikhel Hospital for the first time in Nepal. Usually orthodontic therapy is meant for putting braces on the labial surface of the teeth which is called labial orthodontic system. Lingual orthodontic system is a purely invisible kind of orthodontic therapy in which braces are placed behind the teeth. The advantages of lingual orthodontic therapy are: invisibility, better biomechanics and improved patient compliance. On the other hand it is difficult to master and costlier than labial orthodontics. We have presented six adjunctive orthodontic cases treated by lingual system with the same end result comparable to labial orthodontic system. PMID:22710545

  17. Dental Extrusion with Orthodontic Miniscrew Anchorage: A Case Report Describing a Modified Method

    Science.gov (United States)

    Horliana, Ricardo Fidos; Horliana, Anna Carolina Ratto Tempestini; Wuo, Alexandre do Vale; Perez, Flávio Eduardo Guillin; Abrão, Jorge

    2015-01-01

    In recent years, the skeletal anchorage through miniscrews has expanded the treatment options in orthodontics (Yamaguchi et al., 2012). We hereby present a modified method for tooth extrusion for cases where crown-lengthening surgery is contraindicated for aesthetic reasons. This modified method uses three orthodontic appliances: a mini-implant, an orthodontic wire, and a bracket. The aim of this case report was to increase the length of the clinical crown of a fractured tooth (tooth 23) by means of an orthodontic extrusion with the modified method of Roth and Diedrich. PMID:25713739

  18. Morphological characterization of as-received and in vivo orthodontic stainless steel archwires.

    Science.gov (United States)

    Daems, Julie; Celis, Jean-Pierre; Willems, Guy

    2009-06-01

    This study was undertaken to evaluate the material degradation of clinical bracket-archwire-contacting surfaces after in vivo orthodontic use. Twenty-four stainless steel multiloop edgewise archwires with two different cross sections (0.016 x 0.016 and 0.016 x 0.022 inches) were used for at least 6 months in the mouths of 14 patients. The surfaces of both as-received (cross-section of 0.016 x 0.016, 0.016 x 0.022, and 0.017 x 0.025 inches) and the in vivo wires were examined using scanning electron microscopy. The as-received wires exhibited an inhomogeneous surface with different surface irregularities resulting from the manufacturing process. For the in vivo archwires, an increase in the variety, type, and number of surface irregularities were observed. Crevice corrosion occurred not only at surface irregularities formed during manufacturing and orthodontic handling but also at the bracket-archwire-contacting surfaces and at the archwire surfaces coated with plaque and food remnants. This corrosion may be linked to the formation of a micro-environment at these locations. In addition, a limited number of signs of degradation induced during in vivo testing due to wear and friction were observed. PMID:19188281

  19. Poisson Brackets of Orthogonal Polynomials

    CERN Document Server

    Cantero, M J; Cantero, Maria Jose; Simon, Barry

    2006-01-01

    For the standard symplectic forms on Jacobi and CMV matrices, we compute Poisson brackets of OPRL and OPUC, and relate these to other basic Poisson brackets and to Jacobians of basic changes of variable.

  20. Correlates of Narrow Bracketing

    DEFF Research Database (Denmark)

    Koch, Alexander; Nafziger, Julia

    We examine whether different phenomena of narrow bracketing can be traced back to some common characteristic and whether and how different phenomena are related. We find that making dominated lottery choices or ignoring the endowment when making risky choices are related phenomena and are both as...

  1. Influence of surface treatments on bond strength of metal and ceramic brackets to a novel CAD/CAM hybrid ceramic material.

    Science.gov (United States)

    Elsaka, Shaymaa E

    2016-01-01

    This study evaluated the effect of four different surface treatments methods on the shear bond strength (SBS) of ceramic and metal brackets to Vita Enamic (VE) CAD/CAM hybrid ceramic. A total of 240 plates (10 mm × 10 mm × 3 mm) were cut from VE ceramic blocks and divided into two groups. In each group, four subgroups were prepared by hydrofluoric acid (HF); phosphoric acid (H3PO4); diamond ceramic grinding bur; and silica coating using CoJet system (CJ). Maxillary central incisor metal (Victory Series) and ceramic (Clarity) brackets were bonded with light-cure composite and then stored in artificial saliva for 1 week and thermocycled. The SBS test was performed, and the failure types were classified with adhesive remnant index scores. Surface morphology of the ceramic was characterized after treatment using a scanning electron microscope. Data were analyzed using two-way ANOVA, Tukey HSD test, and Weibull analysis. SBS was significantly affected by the type of bracket and by type of treatment (P  HF > Bur > H3PO4. Ceramic bracket showed higher SBS compared to metal bracket. Adhesive failures between the ceramic and composite resin were the predominant mode of failure in all groups. Surface treatment of VE CAD/CAM hybrid ceramic with silica coating enhanced the adhesion with ceramic and metal brackets. PMID:25585677

  2. Plasma arc curing lights for orthodontic bonding.

    Science.gov (United States)

    Klocke, Arndt; Korbmacher, Heike M; Huck, Lothar G; Kahl-Nieke, Bärbel

    2002-12-01

    Xenon plasma arc lights were introduced recently for light-cured orthodontic bonding. Compared with a conventional tungsten-quartz-halogen light source, these high-intensity lights promise a dramatic reduction in curing time. The purpose of this in vitro investigation was to evaluate bond strength with 2 commercially available plasma arc lights and reduced curing intervals. Brackets were bonded to 150 extracted human teeth (75 premolars, 75 incisors) with a composite adhesive. Intervals of 2 and 6 seconds were used for curing with the plasma arc lights; a control group was bonded with a halogen light source and 20 seconds of light exposure per bracket. Bond strength testing was performed with a universal testing machine. A substantial reduction in curing time was possible with both plasma arc units. Significantly lower bond strength values were found for premolar brackets bonded with plasma arc curing lights and the shortest curing interval of 2 seconds compared with the longer curing time of 6 seconds or the standard curing time with the halogen light. Although 2 seconds of curing might be adequate to achieve acceptable bond strength values for the incisors, the Weibull analysis indicated a higher probability of bond failure for premolar brackets in particular. Six seconds of curing time is recommended for bonding stainless steel brackets with xenon plasma arc light sources. PMID:12490876

  3. Impact of brackets on smile esthetics: laypersons and orthodontists perception

    Scientific Electronic Library Online (English)

    Seandra Cordeiro de, Oliveira; Rachel D' Aurea, Furquim; Adilson Luiz, Ramos.

    2012-10-01

    Full Text Available OBJETIVO: esse estudo analisou a influência dos aparelhos ortodônticos na estética do sorriso em avaliação por adolescentes, adultos e ortodontistas. MÉTODOS: foram utilizadas fotografias faciais do sorriso de uma jovem mulher, usando-se as seguintes combinações: aparelho ortodôntico de metal com li [...] gaduras de diferentes cores (verde, vermelho e cinza); aparelho ortodôntico cerâmico (ligadura transparente); e sem aparelho - resultando em cinco fotografias de 15x20cm. Para a avaliação das fotografias, 16 adolescentes leigos, 16 adultos leigos e 16 ortodontistas foram selecionados de forma randômica. As fotografias foram aleatoriamente organizadas em um álbum, acompanhadas de uma escala visual analógica (EVA) para o registro das notas. As notas das duas avaliações de cada grupo (adolescentes, adultos e ortodontistas) foram submetidas à análise de erro (teste pareado de Wilcoxon) e comparação múltipla de grupos pelo teste de Kruskal-Wallis com significância de 5%. RESULTADOS: ortodontistas, adultos e adolescentes concordaram em suas opiniões, porém, os ortodontistas deram notas menores em suas avaliações. Pôde ser observado que os braquetes cerâmicos foram mais aceitos, considerando-se a estética do sorriso, uma vez que os braquetes metálicos tiveram as menores notas. CONCLUSÃO: ortodontistas, adultos e adolescentes parecem preferir soluções estéticas durante o tratamento ortodôntico. Abstract in english OBJECTIVE: This study evaluated the influence of orthodontic appliances on smile esthetics assessed by lay adolescents, lay adults and orthodontists. METHODS: A facial photograph of a smiling young woman was used under the following conditions: With metal orthodontic brackets ligated by different el [...] astic ligature colors (green, red and gray), with ceramic bracket brackets (transparent elastic ligature) and without brackets, totaling five 15 x 20 cm pictures. For the photograph assessment, 16 lay adolescents, 16 lay adults and 16 orthodontists were randomly selected. The photographs were randomly arranged in an album, followed by a visual analog scale (VAS) for the scores registration. Scores in both evaluations of each group of evaluators (adolescents, adults and orthodontists) were submitted to error analysis by WILCOXON test and multiple comparison among groups performed by Kruskal - Wallis at 5% significance. RESULTS: Orthodontists, adults and adolescents agreed in their opinions, although the orthodontists gave lower scores in their assessments. It could be observed that ceramic brackets were more acceptable concerning the smile esthetics, whereas the metal brackets received the lowest scores. CONCLUSION: Orthodontists, adults and even adolescents seem to prefer esthetic solutions during orthodontic treatment.

  4. Development and evaluation of a reinforced polymeric biomaterial for use as an orthodontic wire

    Science.gov (United States)

    Zufall, Scott William

    Composite archwires have the potential to provide esthetic and functional improvements over conventional wires. As part of an ongoing effort to bring these materials into general use, composite wires were fabricated using a photo-pultrusion manufacturing technique, and subsequently coated with a 10 mum layer of poly(chloro-p-xylylene). Coated and uncoated composites were subjected to several different evaluations to assess their ability to perform the functions of an orthodontic archwire. An investigation of the viscoelastic behavior of uncoated composite wires was conducted at a physiological temperature of 37°C using a bend stress relaxation test. Over 90 day testing periods, energy losses increased with decreasing reinforcement levels from to 8% of the initial wire stress. Final viscous losses were 1% for all reinforcement levels. Relaxed elastic moduli for the composite wires were comparable to the reported elastic moduli of conventional orthodontic wires that are typically used for initial and intermediate alignment procedures. Frictional characteristics were evaluated in passive and active configurations for uncoated composite wires against three contemporary orthodontic brackets. Kinetic coefficients of friction were the same for all wire-bracket combinations tested and were slightly lower than the reported coefficients of other initial and intermediate alignment wires. Wear patterns on the wires, which were largely caused by sharp leading edges of the bracket slots, were characteristic of plowing and cutting wear behaviors. This wear caused glass fibers to be released from the surface of the wires, presenting a potential irritant. Coated composite wires were subjected to the same frictional analysis as the uncoated wires. A mathematical model of the archwire-bracket system was derived using engineering mechanics, and used to define a coefficient of binding. The coating increased the frictional coefficients of the wires by 72%, yet the binding coefficient was unchanged. When frictional data for initial and intermediate alignment wires were compared, the coated composites had higher friction than all but one couple. However, binding coefficients were comparable. Glass fibers were contained for all testing conditions, although the coating was often damaged by plowing or cutting wear. Overall, the coating improved the clinical acceptability of the composite wires.

  5. Lingual Orthodontics simplified : Incognito -customization perfected

    Directory of Open Access Journals (Sweden)

    Haroutioun Dedeyan

    2013-01-01

    Full Text Available Esthetic orthodontics is the need of the hour, fuelled by the increasing number of adult patients seeking orthodontic treatment. Alternatives to labial appliance include clear aligners and lingual appliance. Conventional lingual treatment is laborious in terms of laboratory setup and manual dexterity of the operator, coupled with less than optimum treatment results. Customization of the appliance to meet varied requirements of each patient due to highly variable lingual morphology within and amongst patients is the key to successful treatment in lingual orthodontics. Efforts at bracket base customization using intra-oral jigs and laboratory setups are fraught with unavoidable errors affecting treatment outcome. With the advent of computer-aided design and computer-aided manufacturing (CAD/CAM technology the Eldorado of true customization is now a reality. This paper introduces the Incognito Appliance System based on custom-made brackets and custom-made series of pre-bent wires using state of art CAD/CAM manufacturing procedures.

  6. Quantitative analysis of S. mutans and S. sobrinus cultivated independently and adhered to polished orthodontic composite resins

    Scientific Electronic Library Online (English)

    Ulises, Velazquez-Enriquez; Rogelio Jose, Scougall-Vilchis; Rosalia, Contreras-Bulnes; Jaime, Flores-Estrada; Shinsuke, Uematsu; Ryozo, Yamaguchi.

    2012-10-01

    Full Text Available In Orthodontics, fixed appliances placed in the oral cavity are colonized by microorganisms. OBJECTIVE: The purpose of this study was to quantitatively determine the independent bacterial colonization of S. mutans and S. sobrinus in orthodontic composite resins. MATERIAL AND METHODS: Seven orthodont [...] ic composite adhesives for bonding brackets were selected and classified into 14 groups; (GIm, GIs) Enlight, (GIIm, GIIs) Grengloo, (GIIIm, GIIIs) Kurasper F, (GIVm, GIVs) BeautyOrtho Bond, (GVm, GVs) Transbond CC, (GVIm, GVIs) Turbo Bond II, (GVIIm, GVIIs) Blugloo. 60 blocks of 4x4x1 mm of each orthodontic composite resin were made (total 420 blocks), and gently polished with sand-paper and ultrasonically cleaned. S. mutans and S. sobrinus were independently cultivated. For the quantitative analysis, a radioactive marker was used to codify the bacteria (³H) adhered to the surface of the materials. The blocks were submerged in a solution with microorganisms previously radiolabeled and separated (210 blocks for S. mutans and 210 blocks for S. sobrinus) for 2 hours at 37ºC. Next, the blocks were placed in a combustion system, to capture the residues and measure the radiation. The statistical analysis was calculated with the ANOVA test (Sheffè post-hoc). RESULTS: Significant differences of bacterial adhesion were found amongst the groups. In the GIm and GIs the significant lowest scores for both microorganisms were shown; in contrast, the values of GVII for both bacteria were significantly the highest. CONCLUSIONS: This study showed that the orthodontic composite resin evaluated in the GIm and GIs, obtained the lowest adherence of S. mutans and S. sobrinus, which may reduce the enamel demineralization and the risk of white spot lesion formation.

  7. Quantitative analysis of S. mutans and S. sobrinus cultivated independently and adhered to polished orthodontic composite resins

    Directory of Open Access Journals (Sweden)

    Ulises Velazquez-Enriquez

    2012-10-01

    Full Text Available In Orthodontics, fixed appliances placed in the oral cavity are colonized by microorganisms. OBJECTIVE: The purpose of this study was to quantitatively determine the independent bacterial colonization of S. mutans and S. sobrinus in orthodontic composite resins. MATERIAL AND METHODS: Seven orthodontic composite adhesives for bonding brackets were selected and classified into 14 groups; (GIm, GIs Enlight, (GIIm, GIIs Grengloo, (GIIIm, GIIIs Kurasper F, (GIVm, GIVs BeautyOrtho Bond, (GVm, GVs Transbond CC, (GVIm, GVIs Turbo Bond II, (GVIIm, GVIIs Blugloo. 60 blocks of 4x4x1 mm of each orthodontic composite resin were made (total 420 blocks, and gently polished with sand-paper and ultrasonically cleaned. S. mutans and S. sobrinus were independently cultivated. For the quantitative analysis, a radioactive marker was used to codify the bacteria (³H adhered to the surface of the materials. The blocks were submerged in a solution with microorganisms previously radiolabeled and separated (210 blocks for S. mutans and 210 blocks for S. sobrinus for 2 hours at 37ºC. Next, the blocks were placed in a combustion system, to capture the residues and measure the radiation. The statistical analysis was calculated with the ANOVA test (Sheffè post-hoc. RESULTS: Significant differences of bacterial adhesion were found amongst the groups. In the GIm and GIs the significant lowest scores for both microorganisms were shown; in contrast, the values of GVII for both bacteria were significantly the highest. CONCLUSIONS: This study showed that the orthodontic composite resin evaluated in the GIm and GIs, obtained the lowest adherence of S. mutans and S. sobrinus, which may reduce the enamel demineralization and the risk of white spot lesion formation.

  8. Cellulose Nanofibre Mesh for Use in Dental Materials

    OpenAIRE

    Anthony J. Ireland; Stephen A. Boyd; Bo Su; Sandy, Jonathan R.

    2012-01-01

    The aim of this study was to produce a 3D mesh of defect free electrospun cellulose acetate nanofibres and to use this to produce a prototype composite resin containing nanofibre fillers. This might find use as an aesthetic orthodontic bracket material or composite veneer for restorative dentistry. In this laboratory based study cellulose acetate was dissolved in an acetone and dimethylacetamide solvent solution and electrospun. The spinning parameters were optimised and lithium chloride adde...

  9. Femtosecond laser etching of dental enamel for bracket bonding.

    Science.gov (United States)

    Kabas, Ayse Sena; Ersoy, Tansu; Gülsoy, Murat; Akturk, Selcuk

    2013-09-01

    The aim is to investigate femtosecond laser ablation as an alternative method for enamel etching used before bonding orthodontic brackets. A focused laser beam is scanned over enamel within the area of bonding in a saw tooth pattern with a varying number of lines. After patterning, ceramic brackets are bonded and bonding quality of the proposed technique is measured by a universal testing machine. The results are compared to the conventional acid etching method. Results show that bonding strength is a function of laser average power and the density of the ablated lines. Intrapulpal temperature changes are also recorded and observed minimal effects are observed. Enamel surface of the samples is investigated microscopically and no signs of damage or cracking are observed. In conclusion, femtosecond laser exposure on enamel surface yields controllable patterns that provide efficient bonding strength with less removal of dental tissue than conventional acid-etching technique. PMID:24045693

  10. Mechanical properties of a new thermoplastic polymer orthodontic archwire

    Energy Technology Data Exchange (ETDEWEB)

    Varela, Juan Carlos; Velo, Marcos [Grupo de investigación en Ortodoncia, Facultad de Odontología, Universidad Santiago de Compostela, Santiago de Compostela (Spain); Espinar, Eduardo; Llamas, Jose Maria [Grupo de investigación en Ortodoncia, Facultad de Odontología, Universidad de Sevilla (Spain); Rúperez, Elisa; Manero, Jose Maria [Dept. C. Materiales e Ing. Metalúrgica, Universitat Politècnica de Catalunya, Centre de Recerca Nanoenginyeria, Member of Biomedical Research Networking Center in Bioengineering, Biomaterials and Nanomedicine, CIBER-BBN (Spain); Javier Gil, F., E-mail: francesc.xavier.gil@upc.edu [Dept. C. Materiales e Ing. Metalúrgica, Universitat Politècnica de Catalunya, Centre de Recerca Nanoenginyeria, Member of Biomedical Research Networking Center in Bioengineering, Biomaterials and Nanomedicine, CIBER-BBN (Spain)

    2014-09-01

    A new thermoplastic polymer for orthodontic applications was obtained and extruded into wires with round and rectangular cross sections. We evaluated the potential of new aesthetic archwire: tensile, three point bending, friction and stress relaxation behaviour, and formability characteristics were assessed. Stresses delivered were generally slightly lower than typical beta-titanium and nickel-titanium archwires. The polymer wire has good instantaneous mechanical properties; tensile stress decayed about 2% over 2 h depending on the initial stress relaxation for up to 120 h. High formability allowed shape bending similar to that associated with stainless steel wires. The friction coefficients were lower than the metallic conventional archwires improving the slipping with the brackets. This new polymer could be a good candidate for aesthetic orthodontic archwires. - Highlights: • A new thermoplastic polymer for orthodontic applications was obtained. • This polymer could be a good candidate for aesthetic orthodontic archwires. • The polymer has good mechanical properties as orthodontic wire coating. • The friction coefficients were lower than the metallic archwires improving the slipping with the brackets. • High formability allowed shape bending similar to that associated with stainless steel wires.

  11. Effect of Activation Mode on Shear Bond Strength of Metallic Brackets

    Scientific Electronic Library Online (English)

    Americo Bortolazzo, Correr; Ana Rosa, Costa; Adriana Simoni, Lucato; Silvia Amelia, Vedovello; Heloisa Cristina, Valdrighi; Mario, Vedovello Filho; Lourenco, Correr-Sobrinho.

    2013-09-01

    Full Text Available O objetivo deste estudo foi avaliar a resistência de união ao cisalhamento (RUC) de braquetes ortodônticos metálicos colados ao dente bovino utilizando resinas compostas ativadas por luz ou quimicamente ativadas. Cento e vinte incisivos mandibulares bovinos foram divididos em 6 grupos (n=20), de aco [...] rdo com o material de colagem: Transbond XT (T); Enforce Dual (ED); Enforce químico (EC); Enforce ativado por luz (EL); Concise Ortodontico (C); e RelyX Unicem Capsula (UN). Braquetes metálicos foram posicionados e firmemente colados aos dentes. A ativação por luz para os grupos T, ED, EL e UN foi realizada em quatro exposições, sendo uma em cada lado do braquete, para um tempo total de exposição de 20 s usando o aparelho XL2500 (3M ESPE). Os grupos EC e C foram ativados quimicamente. Após, todas as amostras foram armazenadas em água deionizada a 37 °C por 24 h. O teste de resistência de união ao cisalhamento foi realizado após o período de armazenagem, à velocidade de 1 mm/minuto. Os dados foram submetidos à Análise de Variância e ao teste de Tukey (?=0,05). O índice de remanescente adesivo (IRA) foi avaliado em aumento de 8x. O valor de RUC (MPa) do grupo C (17,72±4,45) foi significantemente maior do que o de outros grupos (p Abstract in english The aim of this study was to evaluate the shear bond strength (SBS) of metallic orthodontic brackets bonded to bovine teeth using light-activated or chemically activated composite resins. One hundred and twenty bovine mandibular incisors were divided into 6 groups (n=20), according to the bonding ma [...] terials: Transbond XT (T); Enforce Dual (ED); Enforce chemical (EC); Enforce Light-activated (EL); Concise Orthodontic (C); and RelyX Unicem Capsule (UN). Metallic brackets were positioned and firmly bonded to the teeth. Light-activation for T, ED, EL and UN was carried out with four exposures on each side of the bracket with 20 s total exposure times using XL2500 (3M ESPE). EC and C were chemically cured. Next, all specimens were stored in deionized water at 37 °C for 24 h. The shear bond strength was carried out at a crosshead speed of 1.0 mm/min. Data were subjected to one-way ANOVA and Tukey's test (?=0.05). The adhesive remnant index (ARI) was evaluated at 8× magnification. C (17.72±4.45) presented significantly higher SBS means (in MPa) than the other groups (p

  12. Orthodontic treatment of an anterior openbite with the aid of corticotomy procedure: Case report

    OpenAIRE

    Ali S. Aljhani; Aldrees, Abdullah M

    2010-01-01

    This case report illustrates the orthodontic treatment combined with the corticotomy technique in an adult patient to accelerate tooth movement and shorten the treatment time. The patient was a 22-year-old woman with an anterior open bite and flared and spaced upper and lower incisors. First, fixed orthodontic appliances (bidimensional edgewise brackets) were bonded, and a week later buccal and lingual corticotomy with alveolar augmentation procedure in the maxillary arch from the first molar...

  13. Halogen light versus LED for bracket bonding: shear bond strength

    Scientific Electronic Library Online (English)

    Paulo Eduardo Guedes, Carvalho; Valdemir Muzulon dos, Santos; Hassan, Isber; Flávio Augusto, Cotrim-Ferreira.

    2013-02-01

    Full Text Available INTRODUÇÃO: os aparelhos de fotopolimerização por LED buscam proporcionar uma luz ativadora fria, que possibilite protocolos de polimerização do material com menor tempo de duração. OBJETIVO: avaliar a resistência à tração da colagem de braquetes, utilizando três tipos de aparelhos fotoativadores: u [...] m de luz halógena (Optilight Plus - Gnatus) e outros dois de LED (Optilight CL - Gnatus; e Elipar Freelight - 3M/Espe). RESULTADOS: comparando os resultados por meio da análise de variância, o aparelho de LED Gnatus apresentou comportamento estatístico inferior em relação às outras fontes de luz, quando ativado por tempo reduzido. Já quando foi utilizado o tempo de 40 segundos, os resultados de polimerização foram compatíveis com as demais fontes avaliadas. O aparelho que apresentou melhor desempenho médio foi o de luz halógena, seguido pelo LED 3M/Espe. CONCLUSÃO: concluiu-se que os LEDs podem ser indicados na prática ortodôntica, uma vez que seja utilizado um protocolo de aplicação da luz com tempo de ativação de 40 segundos. Abstract in english INTRODUCTION: LED light-curing devices seek to provide a cold light activator which allows protocols of material polymerization with shorter duration. OBJECTIVE: The present study aimed to evaluate the shear bond strength of bracket bonding using three types of light-curing devices: One with halogen [...] light (Optilight Plus - Gnatus) and two with LEDs (Optilight CL - Gnatus and Elipar Freelight - 3M/ESPE). RESULTS: Comparing the results by analysis of variance, the Gnatus LED device showed an inferior statistical behavior in relation to other light sources, when activated by a short time. But, when it was used for 40 seconds, the polymerization results were consistent with the other evaluated sources. The device with the best average performance was the halogen light, followed by the 3M/ESPE LED. CONCLUSION: It was concluded that the LEDs may be indicated in orthodontic practice, as long as a protocol is used for the application of light with the activation time of 40 seconds.

  14. Shear bond strength of new and recycled brackets to enamel

    Scientific Electronic Library Online (English)

    Stenyo Wanderley, Tavares; Simonides, Consani; Darcy Flávio, Nouer; Maria Beatriz Borges de Araújo, Magnani; Paulo Roberto Aranha, Nouer; Laura Moura, Martins.

    Full Text Available O objetivo deste estudo foi avaliar in vitro a resistência ao cisalhamento de bráquetes reciclados. Foram utilizados 50 pré-molares humanos, extraídos com finalidade ortodôntica, nos quais foi feita a colagem de bráquetes (S2C-03Z; Dental Morelli, Brasil) com resina composta quimicamente ativada (Co [...] ncise Ortodôntico; 3M, EUA). Os dentes foram divididos aleatoriamente em 5 grupos (n=10). No grupo I (controle), os bráquetes colados permaneceram fixados até o momento do teste de cisalhamento (ou seja, não foram feitos procedimentos de remoção e nova colagem dos bráquetes). Nos grupos II, III e IV, os bráquetes foram removidos e reutilizados após reciclagem com jateamento de óxido de alumínio (90 µm), desgaste com ponta abrasiva de carboneto de silício ou processo industrial por uma empresa especializada (Abzil-Lancer, Brasil), respectivamente. No grupo V, os bráquetes foram removidos e bráquetes novos foram colados sobre o esmalte. Os ensaios de cisalhamento foram realizados numa máquina Instron com velocidade de 0,5 mm/min e os resultados foram submetidos à análise de variância e teste de Tukey com nível de significância de 5 %. Não houve diferença estatisticamente significante (p>0,05) entre os bráquetes do grupo controle (0,52 kgf/mm²), reciclados com óxido de alumínio (0,34 kgf/mm²) e bráquetes novos colados sobre o esmalte onde anteriormente havia bráquetes fixados (0,43 kgf/mm²). Bráquetes reciclados pela empresa especializada (0,28 kgf/mm²) e pelo desgaste com carboneto de silício (0,14 kgf/mm²) apresentaram os menores valores de resistência ao cisalhamento, com diferença estatisticament significante (p Abstract in english The purpose of this study was to evaluate in vitro the shear bond strength of recycled orthodontic brackets. S2C-03Z brackets (Dental Morelli, Brazil) were bonded to the buccal surfaces of 50 extracted human premolars using Concise Orthodontic chemically cured composite resin (3M, USA). The teeth we [...] re randomly assigned to 5 groups (n=10), as follows. In group I (control), the bonded brackets remained attached until shear testing (i.e., no debonding/rebonding). In groups II, III and IV, the bonded brackets were detached and rebonded after recycling by 90-mum particle aluminum oxide blasting, silicon carbide stone grinding or an industrial process at a specialized contractor company (Abzil-Lancer, Brazil), respectively. In group V, the bonded brackets were removed and new brackets were bonded to the enamel surface. Shear bond strength was tested in an Instron machine at a crosshead speed of 0.5 mm/min. Data were analyzed statistically by ANOVA and Tukey's test at 5% significance level. There was no statistically significant difference (p>0.05) between the control brackets (0.52 kgf/mm²), brackets recycled by aluminum oxide blasting (0.34 kgf/mm²) and new brackets attached to previously bonded teeth (0.43 kgf/mm²). Brackets recycled by the specialized company (0.28 kgf/mm²) and those recycled by silicon carbide stone grinding (0.14 kgf/mm²) showed the lowest shear strength means and differed statistically from control brackets (0.52 kgf/mm²) (p

  15. Evaluation In Vitro of Frictional Resistance of Self-Ligating Esthetic and Conventional Brackets / Evaluación In Vitro de la Resistencia Friccional en Brackets de Autoligado Estéticos y Convencionales

    Scientific Electronic Library Online (English)

    Maria Rita Danelon do, Amaral; Perrim Smith, Neto; Matheus Melo, Pithon; Dauro Douglas, Oliveira.

    2014-09-01

    Full Text Available El objetivo fue evaluar la resistencia a la fricción producida en de brackets de autoligado estéticos y convencionales durante la simulación mecánica de deslizamiento ortodóncico. Se utilizaron cuatro tipos diferentes de soportes: 3 de tipo autoligado de diferentes marcas (Clarity SL, 3M Unitek; Dam [...] on 3®, Ormco Corporation; In-Ovation C®, GAC International), además de brackets estéticos convencionales (Radiance®, American Orthodontics) asociado con ligaduras elásticas convencionales (Sani-tie®, GAC International) y ligaduras de baja fricción (Slide®, Leone). Para simular la mecánica de deslizamiento, se utilizaron alambres de acero inoxidable con un espesor de 0,018" y 0,017"x0.025" (GAC Internacional). Cinco grupos (n = 10) fueron sometidos a cinco pruebas mecánicas consecutivas en una máquina de prueba universal modelo Emic DL ® 500. Los resultados mostraron niveles bajos de fricción en todos brackets de autoligado probados y con el uso de alambre de 0.018" (p0,05). Por otra parte, los brackets estéticos convencionales asociados con ligaduras convencionales resultaron tener una mayor resistencia a la fricción con ambos alambres probados (p>0,05). Todos los brackets de autoligado presentan niveles de fricción más bajo que los accesorios convencionales. El brackets activo de autoligado In-Ovation C, demostró un mayor grado de fuerza friccional cuando se asocia con alambre rectangular. La ligadura Slide® puede ser una alternativa al uso de brackets de autoligado. Abstract in english The objective of this study was to evaluate the frictional resistance created in self-ligating esthetic and conventional brackets during simulated orthodontic sliding mechanics. Four different types of brackets were used: 3 self-ligating type of different brands (Clarity SL, 3M Unitek; Damon 3®, Orm [...] co Corporation; In-Ovation C®, GAC International), in addition to conventional esthetic brackets (Radiance®, American Orthodontics) associated with conventional elastic ligatures (Sani-tie®, GAC International) and low friction ligatures (Slide®, Leone). To simulate sliding mechanics, stainless steel wires with thicknesses of 0.018" and 0.017"x0.025" (GAC International) were used. Five groups (n=10) were submitted to five consecutive mechanical tests in a universal test machine model Emic® DL 500. The results showed low frictional levels in all tested self-ligating brackets and with use of 0.018" wire (p0.05). Moreover, conventional esthetic brackets associated with conventional ligatures resulted in greater frictional resistance with both wires tested (p>0.05). All the self-ligating brackets presented lower frictional levels than the conventional accessories. Active self-ligating bracket In-Ovation C, demonstrated higher degree of frictional force when associated with rectangular wire. The Slide® ligature may be an alternative to the use of self-ligating brackets.

  16. Corticotomy-assisted orthodontics

    OpenAIRE

    Cano, J.; Campo, Julián; Bonilla, Elena; Colmenero Ruiz, César

    2012-01-01

    The use of orthodontic treatment in adult patients is becoming more common and these patients have different requirements specially regarding duration of treatment and facial and dental aesthetics. Alveolar corticotomy is an effective means of accelerating orthodontic treatment. This literature revision include an historical background, biological and orthodontic fundamentals and the most significant clinical applications of this technique. Orthodontic treatment time is reduced with this tech...

  17. Effect of light-curing units in shear bond strength of metallic brackets: an in vitro study

    Directory of Open Access Journals (Sweden)

    Luciana Borges Retamoso

    2010-02-01

    Full Text Available OBJECTIVES: To determine the influence of the light curing units on the shear bond strength of orthodontic brackets. MATERIAL AND METHODS: Seventy-two premolars were divided into six groups (n=12: Group I: brackets bonded with Transbond and polymerization with halogen light; Group II: Transbond and LED; Group III: Fuji Ortho and halogen light; Group IV: Fuji Ortho and LED; Group V: Fuji Ortho, without acid and halogen light; Group VI: Fuji Ortho, without acid and LED. The groups were tested to shear strength in a universal testing machine at a crosshead speed of 0.5 mm/min. Data were analyzed statistically by ANOVA and Tukey's test. RESULTS: The composite resin presented higher shear bond strength than the resin-modified glass ionomer cement (p0.05. CONCLUSION: The shear bond strength was influenced by the material but not by the light-curing unit. The use of LED reduced the experimental time by approximately 60%, with the same curing efficiency.

  18. Effect of light-curing units in shear bond strength of metallic brackets: an in vitro study

    Scientific Electronic Library Online (English)

    Luciana Borges, Retamoso; Niége Michelle Lazzari, Onofre; Luciane, Hann; Ernani Menezes, Marchioro.

    2010-02-01

    Full Text Available OBJECTIVES: To determine the influence of the light curing units on the shear bond strength of orthodontic brackets. MATERIAL AND METHODS: Seventy-two premolars were divided into six groups (n=12): Group I: brackets bonded with Transbond and polymerization with halogen light; Group II: Transbond and [...] LED; Group III: Fuji Ortho and halogen light; Group IV: Fuji Ortho and LED; Group V: Fuji Ortho, without acid and halogen light; Group VI: Fuji Ortho, without acid and LED. The groups were tested to shear strength in a universal testing machine at a crosshead speed of 0.5 mm/min. Data were analyzed statistically by ANOVA and Tukey's test. RESULTS: The composite resin presented higher shear bond strength than the resin-modified glass ionomer cement (p0.05). CONCLUSION: The shear bond strength was influenced by the material but not by the light-curing unit. The use of LED reduced the experimental time by approximately 60%, with the same curing efficiency.

  19. A study of a novel aesthetic archwire on its frictional properties and its applications to orthodontics

    OpenAIRE

    Chai Kiat Chng; Kelvin Foong; Narayan Gandedkar; Yiong Huak Chan; Chong Lin Chew

    2014-01-01

    Objectives: To compare sliding friction of prototype 0.018-inch fiber-reinforced polymer composite (FRPC) archwire with 0.018-inch nickel titanium archwire using various bracket-arch wire combinations. Materials and Methods: Two wires were tested against four different brackets (3M Gemini Twin bracket; 3M Clarity metal-reinforced ceramic bracket; Ormco Inspire ICE ceramic bracket; and 3M SmartClip) using the Universal testing machine to study and compare frictional characteristics. Results: T...

  20. The spectrum of Apert syndrome: phenotype, particularities in orthodontic treatment, and characteristics of orthognathic surgery

    Directory of Open Access Journals (Sweden)

    Ehmer Ulrike

    2007-02-01

    Full Text Available Abstract In the PubMed accessible literature, information on the characteristics of interdisciplinary orthodontic and surgical treatment of patients with Apert syndrome is rare. The aim of the present article is threefold: (1 to show the spectrum of the phenotype, in order (2 to elucidate the scope of hindrances to orthodontic treatment, and (3 to demonstrate the problems of surgery and interdisciplinary approach. Children and adolescents who were born in 1985 or later, who were diagnosed with Apert syndrome, and who sought consultation or treatment at the Departments of Orthodontics or Craniomaxillofacial Surgery at the Dental School of the University Hospital of Münster (n = 22; 9 male, 13 female were screened. Exemplarily, three of these patients (2 male, 1 female, seeking interdisciplinary (both orthodontic and surgical treatment are presented. Orthodontic treatment before surgery was performed by one experienced orthodontist (AH, and orthognathic surgery was performed by one experienced surgeon (UJ, who diagnosed the syndrome according to the criteria listed in OMIM™. In the sagittal plane, the patients suffered from a mild to a very severe Angle Class III malocclusion, which was sometimes compensated by the inclination of the lower incisors; in the vertical dimension from an open bite; and transversally from a single tooth in crossbite to a circular crossbite. All patients showed dentitio tarda, some impaction, partial eruption, idopathic root resorption, transposition or other aberrations in the position of the tooth germs, and severe crowding, with sometimes parallel molar tooth buds in each quarter of the upper jaw. Because of the severity of malocclusion, orthodontic treatment needed to be performed with fixed appliances, and mainly with superelastic wires. The therapy was hampered with respect to positioning of bands and brackets because of incomplete tooth eruption, dense gingiva, and mucopolysaccharide ridges. Some teeth did not move, or moved insufficiently (especially with respect to rotations and torque irrespective of surgical procedures or orthodontic mechanics and materials applied, and without prognostic factors indicating these problems. Establishing occlusal contact of all teeth was difficult. Tooth movement was generally retarded, increasing the duration of orthodontic treatment. Planning of extractions was different from that of patients without this syndrome. In one patient, the sole surgical procedure after orthodontic treatment with fixed appliances in the maxilla and mandible was a genioplasty. Most patients needed two- jaw surgery (bilateral sagittal split osteotomy [BSSO] with mandibular setback and distraction in the maxilla. During the period of distraction, the orthodontist guided the maxilla into final position by means of bite planes and intermaxillary elastics. To our knowledge, this is the first article in the PubMed accessible literature describing the problems with respect to interdisciplinary orthodontic and surgical procedures. Although the treatment results are not perfect, patients undergoing these procedures benefit esthetically to a high degree. Patients need to be informed with respect to the different kinds of extractions that need to be performed, the increased treatment time, and the results, which may be reached using realistic expectations.

  1. Finite element modeling of superelastic nickel-titanium orthodontic wires.

    Science.gov (United States)

    Naceur, Ines Ben; Charfi, Amin; Bouraoui, Tarak; Elleuch, Khaled

    2014-11-28

    Thanks to its good corrosion resistance and biocompatibility, superelastic Ni–Ti wire alloys have been successfully used in orthodontic treatment. Therefore, it is important to quantify and evaluate the level of orthodontic force applied to the bracket and teeth in order to achieve tooth movement. In this study, three dimensional finite element models with a Gibbs-potential-based-formulation and thermodynamic principles were used. The aim was to evaluate the influence of possible intraoral temperature differences on the forces exerted by NiTi orthodontic arch wires with different cross sectional shapes and sizes. The prediction made by this phenomenological model, for superelastic tensile and bending tests, shows good agreement with the experimental data. A bending test is simulated to study the force variation of an orthodontic NiTi arch wire when it loaded up to the deflection of 3 mm, for this task one half of the arch wire and the 3 adjacent brackets were modeled. The results showed that the stress required for the martensite transformation increases with the increase of cross-sectional dimensions and temperature. Associated with this increase in stress, the plateau of this transformation becomes steeper. In addition, the area of the mechanical hysteresis, measured as the difference between the forces of the upper and lower plateau, increases. PMID:25458153

  2. Orthodontic loading of titanium miniplates in dogs

    DEFF Research Database (Denmark)

    Cornelis, Marie; Vandergugten, S; Mahy, P; De Clerck, H J; Lengelé, B; D'Hoore, W; Nyssen-Behets, C

    2008-01-01

    OBJECTIVES: The objectives of this animal study were to evaluate if orthodontic loading has an impact on osseointegration of screws supporting miniplates, and to describe the histological components of the bone-screw interface. MATERIALS AND METHODS: Eighty orthodontic miniplates were placed in the jaws of 10 dogs. After 2 weeks, a 125 g force was applied between the miniplates of one upper quadrant of each dog and between those of the controlateral lower quadrant. The others, nonloaded miniplat...

  3. Desmistificando os braquetes autoligáveis / Demystifying self-ligating brackets

    Scientific Electronic Library Online (English)

    Renata, Sathler; Renata Gonçalves, Silva; Guilherme, Janson; Nuria Cabral Castello, Branco; Marcelo, Zanda.

    2011-04-01

    Full Text Available Atualmente, os braquetes autoligáveis têm sido associados a tratamentos mais rápidos e eficazes, o que desperta a curiosidade em compará-los ao sistema convencional. Ao contrário dos braquetes tradicionais, os autoligáveis não necessitam de ligaduras, sejam elásticas ou metálicas. A literatura é far [...] ta em concluir que essa característica diminui, ostensivamente, a resistência do atrito durante as mecânicas de deslize. Além disso, existem alegações sobre a dimimuição da necessidade de extrações e de expansão maxilar com o uso desses acessórios. Portanto, o objetivo dessa revisão de literatura foi buscar os mais novos estudos a respeito dos aparelhos autoligáveis atualmente utilizados nos tratamentos ortodônticos, confirmando ou retificando as especulações vigentes. Abstract in english Currently self-ligating brackets have been associated to faster and more efficient treatments, which arouse the curiosity to compare them to the conventional system. Unlike traditional appliances, self-ligating brackets do not require elastomeric or metal ligatures. The literature is abundant in con [...] cluding that this feature decreases, ostensibly, the friction resistance during the sliding mechanics. Moreover, there are reports on minimizing the need of extractions and maxillary expansion using these accessories. Therefore, the purpose of this literature review was to seek the newest studies about the self-ligating brackets currently used in orthodontic treatments, confirming or correcting current speculations.

  4. Indirect orthodontic bonding - a modified technique for improved efficiency and precision

    Scientific Electronic Library Online (English)

    Lincoln Issamu, Nojima; Adriele Silveira, Araújo; Matheus, Alves Júnior.

    2015-06-01

    Full Text Available INTRODUÇÃO: a técnica de colagem indireta prioriza a otimização do procedimento de montagem do aparelho fixo na clínica ortodôntica, assegurando, entre outras, vantagens relacionadas à precisão no posicionamento dos braquetes. Nesse procedimento clínico laboratorial, o material e o método de confec [...] ção da moldeira de transferência são determinantes no quesito precisão. OBJETIVO: este artigo descreve uma técnica de colagem indireta simples, eficiente e reprodutível, para que o procedimento possa ser realizado com sucesso. Variáveis que exercem influência sobre o procedimento são analisadas e discutidas, a fim de auxiliar o profissional a adotar, de forma rotineira, a técnica de colagem indireta em sua prática clínica. Abstract in english INTRODUCTION: The indirect bonding technique optimizes fixed appliance installation at the orthodontic office, ensuring precise bracket positioning, among other advantages. In this laboratory clinical phase, material and methods employed in creating the transfer tray are decisive to accuracy. OBJEC [...] TIVE: This article describes a simple, efficient and reproducible indirect bonding technique that allows the procedure to be carried out successfully. Variables influencing the orthodontic bonding are analyzed and discussed in order to aid professionals wishing to adopt the indirect bonding technique routinely in their clinical practice.

  5. Moshinsky brackets for light nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Znojil, M.

    1977-01-01

    A new formula for calculation of the Moshinsky brackets is derived. As its consequence, simple formulas for the angle-averaged Pauli projector matrix elements and for the transformed two-particle oscillator wave functions are given. (AIP)

  6. Orthodontic Implants: Concepts for the Orthodontic Practitioner

    Science.gov (United States)

    Elias, Carlos Nelson; de Oliveira Ruellas, Antônio Carlos; Fernandes, Daniel Jogaib

    2012-01-01

    Orthodontic implants have become a reliable method in orthodontic practice for providing temporary additional anchorage. These devices are useful to control skeletal anchorage in less compliant patients or in cases where absolute anchorage is necessary. There are a great number of advantages in this new approach which include easy insertion, decreased patient discomfort, low price, immediate loading, reduced diameter, versatility in the forces to be used, ease of cleaning, and ease of removal. However, a proper management of the screws by the practitioner is necessary in order to increase the success rate of the technique. The purpose of this paper is to update practitioners on the current concepts of orthodontic implants and orthodontic mechanics. PMID:23209470

  7. Effect of different enamel conditionings on the bond strength of glass ionomer cement and ceramic brackets

    Scientific Electronic Library Online (English)

    Dauro Douglas, Oliveira; Thomas Gerard, Bradley; Matheus Melo, Pithon; Mariele Cristina Garcia, Pantuzo; Emílio, Akaki; Virendra, Dhuru.

    2014-12-01

    Full Text Available Aim: To evaluate the effect of different enamel conditionings on the shear bond strength (SBS) and bond failure patterns of a resin modified glass ionomer cement (RMGIC) used to bond ceramic brackets. Methods: 105 human premolars extracted for orthodontic reasons were divided into 7 groups according [...] to the enamel surface treatments: conditioners (35% phosphoric acid and 10% polyacrylic acid), type of adhesive (Transbond(r) and Fuji Ortho LC Capsule(r)), washing time and drying of the surface. Results: A significant p0.05) to the group that had brackets bonded with composite resin. The two groups that had enamel prepared with polyacrylic acid and brackets bonded with GIC on a wet surface showed significantly lower shear bond strength than the control group (p

  8. Improvement of orthodontic friction by coating archwire with carbon nitride film

    Energy Technology Data Exchange (ETDEWEB)

    Wei Songbo [State Key Laboratory of Tribology, Tsinghua University, Beijing 100084 (China); Shao Tianmin, E-mail: shaotm@mail.tsinghua.edu.cn [State Key Laboratory of Tribology, Tsinghua University, Beijing 100084 (China); Ding Peng [Department of Orthodontics, Peking University School and Hospital of Stomatology, Beijing 100081 (China)

    2011-10-01

    In order to reduce frictional resistance between archwire and bracket during orthodontic tooth movement, carbon nitride (CNx) thin films were deposited on the surface of archwires with ion beam assisted deposition (IBAD). The energy-dispersive X-ray spectrometer (EDS) analysis showed that the CNx film was successfully deposited on the surface of the orthodontic wires. X-ray photoelectron spectroscopy (XPS) analysis suggested that the deposited CNx film was sp{sup 2} carbon dominated structures, and diversiform bonds (N-C, N{identical_to}C, et al.) coexisted in the film. The friction tests indicated that the CNx film significantly reduced the wire-bracket friction both in ambient air and in artificial saliva. The sp{sup 2}C rich structure of the CNx film as well as its protection function for the archwire was responsible for the low friction of the wire-bracket sliding system.

  9. Improvement of orthodontic friction by coating archwire with carbon nitride film

    International Nuclear Information System (INIS)

    In order to reduce frictional resistance between archwire and bracket during orthodontic tooth movement, carbon nitride (CNx) thin films were deposited on the surface of archwires with ion beam assisted deposition (IBAD). The energy-dispersive X-ray spectrometer (EDS) analysis showed that the CNx film was successfully deposited on the surface of the orthodontic wires. X-ray photoelectron spectroscopy (XPS) analysis suggested that the deposited CNx film was sp2 carbon dominated structures, and diversiform bonds (N-C, N?C, et al.) coexisted in the film. The friction tests indicated that the CNx film significantly reduced the wire-bracket friction both in ambient air and in artificial saliva. The sp2C rich structure of the CNx film as well as its protection function for the archwire was responsible for the low friction of the wire-bracket sliding system.

  10. Evaluation of shear bond strength of different treatments of ceramic bracket surfaces Avaliação da resistência ao cisalhamento de diferentes tratamentos na superfície de braquetes cerâmicos

    Directory of Open Access Journals (Sweden)

    Patrícia Helou Ramos Andrade

    2012-08-01

    Full Text Available OBJECTIVE: To evaluate the bonding strength of the ceramic bracket and composite resin restoration interface, using four types of treatment on the base of the bracket. METHODOLOGY: 48 photoactivated composite resin discs were used (FiltekTM Z250 contained in specimens and divided into 4 groups of 12 specimens for each group according to the type of treatment performed on the base of the brackets. Once the brackets were bonded, the specimens were subjected to shear stress carried out in a universal testing machine (MTS: 810 Material Test System calibrated with a fixed speed of 0.5 mm / minute. The values obtained were recorded and compared by means of appropriate statistical tests - analysis of variance and then Tukey's test. RESULTS AND CONCLUSIONS: The surfaces of ceramic brackets conditioned with 10% hydrofluoric acid for 1 minute, followed by aluminum oxide blasting, 50µ, after silane application and primer application, was considered the best method to prepare surfaces of ceramic brackets prior to orthodontic esthetic bonding.OBJETIVO: avaliar a resistência à união da interface entre braquete cerâmico e restauração de resina composta, empregando quatro tipos de tratamento na base do braquete. MÉTODOS: foram utilizados 48 discos de resina fotoativada (Filtek® Z250 incluídos em corpos de prova, divididos em quatro grupos, com 12 espécimes em cada grupo, de acordo com o tipo de tratamento realizado na base do braquete. Uma vez colados os braquetes, os corpos de prova foram submetidos à tensão de cisalhamento, realizado numa máquina universal de ensaios (MTS: 810 Material Test System calibrada com velocidade fixa de 0,5mm/min. Os valores obtidos foram registrados e comparados por meio de médias, utilizando-se testes estatísticos adequados (análise de Variância e, posteriormente, teste de Tukey. RESULTADOS E CONCLUSÕES: o condicionamento das superfícies dos braquetes cerâmicos com ácido hidrofluorídrico a 10% por 1 minuto, seguido do jateamento com óxido de alumínio com 50um de tamanho, e posterior aplicação do silano e, depois, aplicação de adesivo, foi considerado o melhor método para o preparo de superfícies de braquetes cerâmicos previamente à colagem estética ortodôntica.

  11. Glass transition and degree of conversion of a light-cured orthodontic composite

    Directory of Open Access Journals (Sweden)

    Michela M. D. S. Sostena

    2009-12-01

    Full Text Available OBJECTIVE: This study evaluated the glass transition temperature (Tg and degree of conversion (DC of a light-cured (Fill Magic versus a chemically cured (Concise orthodontic composite. MATERIAL AND METHODS: Anelastic relaxation spectroscopy was used for the first time to determine the Tg of a dental composite, while the DC was evaluated by infrared spectroscopy. The light-cured composite specimens were irradiated with a commercial LED light-curing unit using different exposure times (40, 90 and 120 s. RESULTS: Fill Magic presented lower Tg than Concise (35-84ºC versus 135ºC, but reached a higher DC. CONCLUSIONS: The results of this study suggest that Fill Magic has lower Tg than Concise due to its higher organic phase content, and that when this light-cured composite is used to bond orthodontic brackets, a minimum energy density of 7.8 J/cm² is necessary to reach adequate conversion level and obtain satisfactory adhesion.

  12. Comparison between two methods for resin removing after bracket debonding

    Directory of Open Access Journals (Sweden)

    Rodrigo De Marchi

    2012-12-01

    Full Text Available OBJECTIVE: The aim of this study was to assess - using scanning electron microscopy (SEM - the effectiveness of two abrasive discs, one made from silicon and one from aluminum oxide, in removing adhesive remnants (AR after debonding orthodontic brackets. METHODS: Ten randomly selected bovine teeth were used, i.e., 2 in the control group, and the other 8 divided into two groups, which had orthodontic brackets bonded to their surface with Concise Orthodontic Adhesive (3M. The following methods were employed - in one single step - to remove AR after debracketing: Group A, Optimize discs (TDV and Group B, Onegloss discs (Shofu, used at low speed. After removing the AR with the aforementioned methods, the teeth were prepared to undergo SEM analysis, and photographs were taken of the enamel surface with 50x magnification. Six examiners evaluated the photographs applying the Zachrisson and Årtun enamel surface index (ESI system (1979. RESULTS: Group A exhibited minor scratches on the enamel surface as well as some AR in some of the photographs, while Group B showed a smoother surface, little or no AR and some abrasion marks in the photographs. No statistically significant differences were found between the two methods and the control group. CONCLUSIONS: The two abrasive discs were effective in removing the AR after bracket debonding in one single step.OBJETIVO: o objetivo deste trabalho foi avaliar, por microscopia eletrônica de varredura, a eficácia de dois discos abrasivos de silicone e óxido de alumínio para a remoção da resina remanescente após a descolagem de braquetes ortodônticos. MÉTODOS: foram utilizados 10 dentes bovinos selecionados aleatoriamente, sendo 2 para o grupo controle e os demais divididos em dois grupos, os quais receberam colagem de braquetes ortodônticos com resina ortodôntica Concise (3M. Os métodos de remoção da resina após a descolagem dos acessórios ortodônticos em apenas uma etapa foram: Grupo A - disco Optimize (TDV; e Grupo B - disco Onegloss (Shofu, empregados em baixa rotação. Após a remoção da resina remanescente pelos métodos mencionados, os dentes foram preparados para serem submetidos à análise em microscopia eletrônica de varredura, obtendo-se fotografias da superfície do esmalte com aumento de 50X. Seis examinadores avaliaram as fotografias seguindo a escala de avaliação de Zachrisson e Arthun (1979. RESULTADOS: no Grupo A, observou-se pequenos arranhões na superfície do esmalte, bem como pouco remanescente de resina em algumas das fotografias; enquanto, no Grupo B, observou-se maior lisura, pouco ou nenhum remanescente de resina e alguns riscos nas fotografias. Não houve diferença estatisticamente significativa entre os dois métodos avaliados e o grupo controle. CONCLUSÃO: os dois discos abrasivos mostraram-se eficientes para remoção da resina remanescente após a descolagem de braquete em única etapa.

  13. Relationship between friction force and orthodontic force at the leveling stage using a coated wire

    Scientific Electronic Library Online (English)

    Masaki, MURAYAMA; Yasuhiro, NAMURA; Takahiko, TAMURA; Hiroaki, IWAI; Noriyoshi, SHIMIZU.

    2013-12-01

    Full Text Available The relationship between orthodontic force and friction produced from an archwire and brackets affects the sliding of the wire in the leveling stage. Objective: The purpose of this study was to evaluate the relationship between force and friction in a small esthetic nickel-titanium (Ni-Ti) wire. [...] Material and Methods: Five esthetic wires (three coated and two plated) and two small, plain Ni-Ti wires (0.012 and 0.014 inches) were used. We performed a three-point bending test according to ISO 15841 and the drawing test with a dental arch model designed with upper linguoversion of the lateral incisor in the arch (displacements of 0.5, 1.0, 2.0 and 3.0 mm), and evaluated the relationship between them. Results: Unloading bending forces of all wires at displacements of less than 1.0 mm were larger than friction forces, but all friction forces at displacements exceeding 2.0 mm were larger than unloading bending forces. The arch likely expands when displacement from the proximal brackets exceeds 1.0 mm. The friction force of a martensite 0.014-inch Ni-Ti wire was significantly greater than those of the other esthetic and austenitic wires. Conclusions: A wire with the smallest possible friction force should be used in cases with more than 1.0 mm displacement.

  14. How Is the Enamel Affected by Different Orthodontic Bonding Agents and Polishing Techniques?

    Science.gov (United States)

    Heravi, Farzin; Shafaee, Hooman; Abdollahi, Mojtaba; Rashed, Roozbeh

    2015-01-01

    Objectives: The objective of this study was to assess the effect of new bonding techniques on enamel surface. Materials and Methods: Sixty upper central incisors were randomly divided into two equal groups. In the first group, metal brackets were bonded using TransbondXT and, in the second group, the same brackets were bonded with Maxcem Elite. The shear bond strength (SBS) of both agents to enamel was measured and the number and length of enamel cracks before bonding, after debonding and after polishing were compared. The number of visible cracks and the adhesive remnant index (ARI) scores in each group were also measured. Results: There were significantly more enamel cracks in the Transbond XT group after debonding and polishing compared to the Maxcem Elite group. There was no significant difference in the length of enamel cracks between the two groups; but, in each group, a significant increase in the length of enamel cracks was noticeable after debonding. Polishing did not cause any statistically significant change in crack length. The SBS of Maxcem Elite was significantly lower than that of Transbond XT (95% confidence interval). Conclusion: Maxcem Elite offers clinically acceptable bond strength and can thus be used as a routine adhesive for orthodontic purposes since it is less likely to damage the enamel. PMID:26622271

  15. How Is the Enamel Affected by Different Orthodontic Bonding Agents and Polishing Techniques?

    Directory of Open Access Journals (Sweden)

    Farzin Heravi

    2015-10-01

    Full Text Available Objectives: The objective of this study was to assess the effect of new bonding techniques on enamel surface.Materials and Methods: Sixty upper central incisors were randomly divided into two equal groups. In the first group, metal brackets were bonded using Trans- bondXT and, in the second group, the same brackets were bonded with MaxcemElite. The shear bond strength (SBS of both agents to enamel was measured and the number and length of enamel cracks before bonding, after debonding and after polishing were compared. The number of visible cracks and the adhesive remnant index (ARI scores in each group were also measured.Results: There were significantly more enamel cracks in the Transbond XT group after debonding and polishing compared to the Maxcem Elite group. There was no significant difference in the length of enamel cracks between the two groups; but, in each group, a significant increase in the length of enamel cracks was noticeable after debonding. Polishing did not cause any statistically significant change in crack length. The SBS of Maxcem Elite was significantly lower than that of Transbond XT (95% confidence interval.Conclusion: Maxcem Elite offers clinically acceptable bond strength and can thus be used as a routine adhesive for orthodontic purposes since it is less likely todamage the enamel.

  16. Relationship between friction force and orthodontic force at the leveling stage using a coated wire

    Directory of Open Access Journals (Sweden)

    Masaki MURAYAMA

    2013-12-01

    Full Text Available The relationship between orthodontic force and friction produced from an archwire and brackets affects the sliding of the wire in the leveling stage. Objective: The purpose of this study was to evaluate the relationship between force and friction in a small esthetic nickel-titanium (Ni-Ti wire. Material and Methods: Five esthetic wires (three coated and two plated and two small, plain Ni-Ti wires (0.012 and 0.014 inches were used. We performed a three-point bending test according to ISO 15841 and the drawing test with a dental arch model designed with upper linguoversion of the lateral incisor in the arch (displacements of 0.5, 1.0, 2.0 and 3.0 mm, and evaluated the relationship between them. Results: Unloading bending forces of all wires at displacements of less than 1.0 mm were larger than friction forces, but all friction forces at displacements exceeding 2.0 mm were larger than unloading bending forces. The arch likely expands when displacement from the proximal brackets exceeds 1.0 mm. The friction force of a martensite 0.014-inch Ni-Ti wire was significantly greater than those of the other esthetic and austenitic wires. Conclusions: A wire with the smallest possible friction force should be used in cases with more than 1.0 mm displacement.

  17. Biodegradation of orthodontic appliances and their effects on the blood level of nickel and chromium. Master's thesis

    Energy Technology Data Exchange (ETDEWEB)

    Barrett, R.D.

    1990-05-01

    Austenitic stainless steels containing approximately 18 percent chromium and 8 percent nickel for orthodontic bands, brackets and wires is universally used in orthodontic practices. With the introduction of nickel-titanium alloys as orthodontic archwires in the 1970's an additional source of patient exposure to metal corrosion products has been introduced. Since the oral environment is particularly ideal for the biodegradation of metals due to its ionic, thermal, microbiologic and enzymatic properties some level of patient exposure to the corrosion products of these alloys is assured.

  18. Orthodontic treatment of an anterior openbite with the aid of corticotomy procedure: Case report.

    Science.gov (United States)

    Aljhani, Ali S; Aldrees, Abdullah M

    2011-04-01

    This case report illustrates the orthodontic treatment combined with the corticotomy technique in an adult patient to accelerate tooth movement and shorten the treatment time. The patient was a 22-year-old woman with an anterior open bite and flared and spaced upper and lower incisors. First, fixed orthodontic appliances (bidimensional edgewise brackets) were bonded, and a week later buccal and lingual corticotomy with alveolar augmentation procedure in the maxillary arch from the first molar to the contralateral first molar, and from canine to canine in the mandibular arch was performed. Orthodontic therapy proceeded with frequent activation of the appliances to retract the incisors every 2 weeks. The total treatment time was 5 months and no adverse effects were observed at the end of active treatment. The addition of the decortication procedure to the conventional orthodontic therapy decreased the duration of treatment significantly. Successful closure of the anterior open bite with adequate overbite and interdigitation of the teeth were achieved. PMID:24151417

  19. Degradation of orthodontic wires under simulated cariogenic and erosive conditions

    Scientific Electronic Library Online (English)

    Laura Cavalcante Lima, JABER; José Augusto, RODRIGUES; Flávia Lucisano Botelho, AMARAL; Fabiana Mantovani Gomes, FRANÇA; Roberta Tarkany, BASTING; Cecilia Pedroso, TURSSI.

    2014-08-04

    Full Text Available This study examined the effect of cariogenic and erosive challenges (CCs and ECs, respectively) on the degradation of copper-nickel-titanium (CuNiTi) orthodontic wires. Sixty wire segments were divided into four treatment groups and exposed to CCs, ECs, artificial saliva, or dry storage (no-treatmen [...] t control). CC and EC were simulated using a demineralizing solution (pH 4.3) and a citric acid solution (pH 2.3), respectively. Following treatment, the average surface roughness (Ra) of the wires was assessed, and friction between the wires and a passive self-ligating bracket was measured. CuNiTi wires subjected to ECs exhibited significantly higher Ra values than did those that were stored in artificial saliva. In contrast, surface roughness was not affected by CCs. Finally, friction between the treated wires and brackets was not affected by ECs or CCs. Our results indicate that CuNiTi orthodontic wires may suffer degradation within the oral cavity, as ECs increased the surface roughness of these wires. However, rougher surfaces did not increase friction between the wire and the passive self-ligating bracket.

  20. A comparative evaluation of the shear bond strength of five different orthodontic bonding agents polymerized using halogen and light-emitting diode curing lights: An in vitro investigation

    Directory of Open Access Journals (Sweden)

    Sujoy Banerjee

    2011-01-01

    Full Text Available Purpose: With the introduction of photosensitive (light-activated restorative materials in orthodontics, various methods have been suggested to enhance the polymerization of the materials used, including use of more powerful light curing devices. Bond strength is an important property and determines the amount of force delivered and the treatment duration. Many light-cured bonding materials have become popular but it is the need of the hour to determine the bonding agent that is the most efficient and has the desired bond strength. Aim: To evaluate and compare the shear bond strengths of five different orthodontic light cure bonding materials cured with traditional halogen light and low-intensity light-emitting diode (LED light curing unit. Materials and Methods: 100 human maxillary premolar teeth, extracted for orthodontic purpose, were used to prepare the samples. 100 maxillary stainless steel bicuspid brackets of 0.018 slot of Roth prescription, manufactured by D-tech Company, were bonded to the prepared tooth surfaces of the mounted samples using five different orthodontic bracket bonding light-cured materials, namely, Enlight, Fuji Ortho LC (resin-modified glass ionomer cement, Orthobond LC, Relybond, and Transbond XT. The bond strength was tested on an Instron Universal testing machine (model no. 5582. Results: In Group 1 (halogen group, Enlight showed the highest shear bond strength (16.4 MPa and Fuji Ortho LC showed the least bond strength (6.59 MPa (P value 0.000. In Group 2 (LED group, Transbond showed the highest mean shear bond strength (14.6 MPa and Orthobond LC showed the least mean shear bond strength (6.27 MPa (P value 0.000. There was no statistically significant difference in the shear bond strength values of all samples cured using either halogen (mean 11.49 MPa or LED (mean 11.20 MPa, as the P value was 0.713. Conclusion: Polymerization with both halogen and LED resulted in shear bond strength values which were above the clinically acceptable range given by Reynolds. The LED light curing units produced comparable shear bond strength to that of halogen curing units.

  1. A influência da variação da curvatura da base do braquete em uma união ortodôntica submetida a diferentes cargas, através do método dos elementos finitos The influence of the variation of the bracket base curvature in a bonded orthodontic attachment submitted by different load cases using the finite element method

    Directory of Open Access Journals (Sweden)

    Cláudio Pereira Viana

    2005-06-01

    Full Text Available Este trabalho procurou avaliar, através do Método dos Elementos Finitos, a resistência ao deslocamento de quatro diferentes bases de braquetes "straight-wire" (Morelli, Unitek, A-Company e Abzil-Lancer na aplicação de forças de torção e cisalhamento, correlacionando essa resistência à melhor adaptação das bases à superfície vestibular dentária. As curvaturas das bases de braquetes utilizados no presente estudo foram descritas em um estudo prévio, enquanto o contorno dentário foi obtido a partir do escaneamento e cálculo da curvatura média vestibular do canino inferior de uma amostra de 30 indivíduos brasileiros. Empregou-se a análise tridimensional por Elementos Finitos da interface esmalte vestibular/cimento/base do braquete para cada marca testada. Forças de 1N, promovendo deslocamento lateral e torção, foram aplicadas no centro da base do braquete e observou-se a distribuição desses esforços sobre os modelos assim como as tensões normais e de cisalhamento geradas. Os resultados mostraram que a base que melhor se adaptou à superfície vestibular construída foi a da marca Unitek, seguida pela marca A-Company, Abzil-Lancer e Morelli. As deformações sofridas pelos braquetes foram inversamente proporcionais à adaptação à superfície dentária. Os maiores picos de tensão localizaram-se nas proximidades do ponto de aplicação da força. A interface adesivo/esmalte foi mais sujeita à falha na adesão que a interface braquete/adesivo. A força de cisalhamento demonstrou ser mais provável de causar falha na adesão quando comparada à força de torção.The objective of this study was to evaluate the adaptability of the four straight-wire brackets bases (Morelli, Unitek, A-Company and Abzil-Lancer to facial surface of a lower canine. The lower canine facial curvature data to be used in the three-dimensional finite element model were established by 30 Brazilian adult individuals and the brackets bases curvature used were described in a prior study. The three-dimensional finite element analysis of the interface enamel/cement/base of bracket for each tested mark was used. Loads of 1N promoting lateral displacement and torsion had been applied in the center of the base of brackets and the distribution of these efforts on the models was observed as well as the normal and shear tensions generated. The results had shown that the base that better fit to facial surface was the one from Unitek, followed by the A-Company, Abzil-Lancer and Morelli.The brackets deformations were inversely proportional to its adaptation.The biggest peaks of tensions had been situated near to the point of force application. The cement/enamel interface was more likely to fail in the adhesion that the bracket/cement interface. The torsion load was less likely to cause damage in the adhesion when compared with the shear load.

  2. Northcroft lecture: how has the spectrum of orthodontics changed over the past decades?

    Science.gov (United States)

    Melsen, Birte

    2011-06-01

    Three aspects have had a significant impact on orthodontics during the last few decades: the appliances being used, the anchorage being used and finally the distribution of patients being treated. Firstly, the marketing of appliances is increasingly leading the orthodontist to outsource important aspects of treatment such as wirebending and bracket positioning. Brackets and wires are being presented as the solution to all problems and metaphysical terms such as 'intelligent design,' 'working brackets' and 'intelligent wires' are dominating advertising and reducing the impact of evidence-based treatment approaches. Secondly, the introduction of skeletal anchorage has potentially widened the spectrum of orthodontics, allowing for treatments that could not be done with conventional appliances. Biomechanical knowledge is, however, mandatory if we agree that the system should not be abused. Thirdly, the orthodontic population comprises an increasing number of adult patients, many of whom are characterized by a degenerated dentition. The treatment of these patients requires a thorough knowledge not only of biomechanics but also of the reaction of the periodontal tissues to various types of loading. They can be treated only with custom-made appliances adapting the force systems and magnitude to the patient-specific treatment goal. In summary, the orthodontic world is being split between 'appliance-driven fast-food orthodontics' where the results to a large extent are dependent on both growth and function and 'orthodontist-driven' 'slow-food' treatments attempting to push the limits of the possible in relation to complicated problems and reversal of degeneration in adult patients. The latter treatments are performed with individualized appliances adapting the force system to the patient. This paper will attempt to summarize the bearing of these factors on present orthodontics. PMID:21677105

  3. The assessment of orthodontic bonding defects: optical coherence tomography followed by three-dimensional reconstruction

    Science.gov (United States)

    Rominu, R.; Sinescu, C.; Rominu, M.; Negrutiu, M.; Petrescu, E.; Pop, D.; Podoleanu, A. Gh.

    2011-10-01

    Orthodontic bonding is a simple yet important procedure that can influence the outcome of treatment in case it is performed incorrectly. An orthodontic treatment shadowed by repeated bonding failures can become unduly long and will decrease patient trust and compliance. Optical coherence tomography has been widely used in ophtalmology but is relatively new to dentistry. Using OCT one can detect aerial inclusions within the orthodontic adhesive or even identify incongruence between the bracket base and the tooth surface. The aim of our study was to identify bonding defects and reconstruct them three-dimensionally in order to be able to characterize them more accurately. We bonded 30 sound human permanent teeth with ceramic orthodontic brackets using a no-mix self-curing orthodontic adhesive. Prior to bonding all teeth were stored in tap water at 4°C and then professionally cleaned with rotary brushes and pumice. The samples were processed by the same person and the rotary brushes were changed after every fifth tooth. All interfaces were investigated by means of OCT and 4 defects were found. Subsequently, the defects were reconstructed threedimensionally using an open-source program. By identifying and reconstructing bonding defects we could assess the quality of the bonding procedure. Since bonding tends to be more accurate in vitro where the environmental conditions are close to ideal, it is probable that defects found in vivo be even greater in number, which leads to the conclusion that this type of investigation is potentially valuable.

  4. A hierarchy of Poisson brackets

    CERN Document Server

    Pavelka, Michal; Esen, Ogul; Grmela, Miroslav

    2015-01-01

    The vector field generating reversible time evolution of macroscopic systems involves two ingredients: gradient of a potential (a covector) and a degenerate Poisson structure transforming the covector into a vector. The Poisson structure is conveniently expressed in Poisson brackets, its degeneracy in their Casimirs (i.e. potentials whose gradients produce no vector field). In this paper we investigate in detail hierarchies of Poisson brackets, together with their Casimirs, that arise in passages from more to less detailed (i.e. more macroscopic) descriptions. In particular, we investigate the passage from mechanics of particles (in its Liouville representation) to the reversible kinetic theory and the passage from the reversible kinetic theory to the reversible fluid mechanics. From the physical point of view, the investigation includes binary mixtures and two-point formulations suitable for describing turbulent flows. From the mathematical point of view, we reveal the Lie algebra structure involved in the p...

  5. Comparison Of Bond Strength Of Orthodontic Molar Tubes Using Different Enamel Etching Techniques And Their Effect On Enamel

    International Nuclear Information System (INIS)

    In fixed orthodontic treatment, brackets and tubes are used for transferring orthodontic forces to the teeth. Those attachments were welded to cemented bands. Fifty years ago, direct bonding of brackets and other attachments has become a common technique in fixed orthodontic treatment. Orthodontists used to band teeth, especially molars and second premolars, to avoid the need for re bonding accessories in these regions of heavy masticatory forces. However, it is a known fact that direct bonding saves chair time as it does not require prior band selection and fitting, has the ability to maintain good oral hygiene, improve esthetics and make easier attachment to crowded and partially erupted teeth. Moreover, when the banding procedure is not performed with utmost care it can damage periodontal and/or dental tissues. Molar tubes bonding decreases the chance of decalcification caused by leakage beneath the bands. Since molar teeth are subjected to higher masticatory impact, especially lower molars, it would be convenient to devise methods capable of increasing the efficiency of their traditional bonding. These methods may include variation in bond able molar tube material, design, bonding materials and etching techniques. For achieving successful bonding, the bonding agent must penetrate the enamel surface; have easy clinical use, dimensional stability and enough bond strength. Different etching techniques were introduced in literature to increase the bond strength which includes: conventional acid etching, sandblasting and laser etching techniques. The process of conventional acid etching technique was invented In (1955) as the surface of enamel has great potential for bonding by micromechanical retention, to form ‘the mechanical lock‘. The primary effect of enamel etching is to increase the surface area. However, this roughens the enamel microscopically and results in a greater surface area on which to bond. By dissolving minerals in enamel, etchants remove the outer 10 micrometers on the enamel surface. The purpose of acid etching is to remove the smear layer and create an irregular surface by preferentially dissolving hydroxyapatite crystals on the outer surface. This topography will facilitate penetration of the fluid adhesive components into the irregularities. After polymerization, the adhesive is locked as proved by Dr. Bounocore into the surface and contributes to micromechanical retention. Sandblasting was introduced in orthodontics in an attempt to achieve proper etching for the enamel surface which would result in a better bond strength through aluminum oxide particles that are emitted from a specific hand piece at a high speed which produce roughness in enamel surfaces. Another method of increasing bond strength is by using an adhesion promoter. The expression 'adhesion promoter' was first used in connection with certain molecules which could achieve chemical bonding in dental structures. The word laser is an acronym for Light Amplification by Stimulated Emission of Radiation. The introduction of laser has revolutionized the bonding procedure. The first laser introduced was the helium-neon laser followed by Nd;YAG and CO2 laser. Then the erbium family(Er;YAG and Er;Cr;YSSG) was introduced to dentistry. It has some advantages such as having no vibration or heat and producing a surface which is acid resistant by altering the calcium to phosphor ratio and formation of less soluble compounds. These characteristics make the erbium family more popular in orthodontics. If laser can achieve the above-mentioned function of acid etching, and even produce a favorable surface for bonding to a restorative material, it may be a viable alternative to acid etching. Although there are studies that have evaluated the effect of laser etching on bond strength, still further studies are needed for evaluating the shear bond strength of orthodontic molar tubes bonded to enamel prepared by the new Er;Cr;YSSG laser, sandblasting versus the conventional acid etching technique

  6. Avaliação da resistência ao cisalhamento de braquetes da técnica lingual colados sobre superfície cerâmica Evaluation of shear strength of lingual brackets bonded to ceramic surfaces

    Directory of Open Access Journals (Sweden)

    Michele Balestrin Imakami

    2011-06-01

    Full Text Available OBJETIVO: avaliar a resistência ao cisalhamento de braquetes metálicos (American Orthodontics utilizados na técnica lingual, colados em facetas de cerâmica. MÉTODOS: foram utilizados 40 corpos de prova divididos em quatro grupos de 10, de acordo com o material de colagem e do preparo da porcelana: Grupo I -resina Sondhi Rapid-Set e ácido fluorídrico; Grupo II -resina Sondhi Rapid-Set e óxido de alumínio; Grupo III -resina Transbond XT e ácido fluorídrico; e Grupo IV -resina Transbond XT e óxido de alumínio. Previamente à colagem, os braquetes foram preparados com base de resina de carga pesada (Z-250 e as facetas de cerâmica receberam aplicação de silano. O teste de cisalhamento foi realizado por uma máquina de ensaios Kratos à uma velocidade de 0,5mm/min. RESULTADOS: os resultados obtidos foram analisados estatisticamente através do teste de Tukey (pOBJECTIVE: The aim of this study was to evaluate the shear strength of lingual metal brackets (American Orthodontics bonded to ceramic veneers. METHODS: A total of 40 specimens were divided into four groups of 10, according to bonding material and ceramics preparation: Group I -Sondhi Rapid-Set resin and Hydrofluoric acid, Group II -Sondhi Rapid-Set resin and aluminum oxide, Group III -Transbond XT resin and Hydrofluoric acid, and Group IV -Transbond XT resin and aluminum oxide. Prior to bonding, the brackets were prepared with heavy-duty resin base (Z-250 and the ceramic veneers were treated with silane. The shear test was conducted with a Kratos testing machine at a speed of 0.5 mm/min. RESULTS: The results were statistically analyzed by the Tukey test (p<0.05 and showed a statistically significant difference between groups I (2.77 MPa and IV (6.00 MPa, and between groups III (3.33 MPa and IV. CONCLUSION: In conclusion, the bonding of lingual brackets to ceramic surfaces exhibited greater shear strength when aluminum oxide was used in association with the two resins utilized in this study, although Transbond XT showed greater shear strength than Sondhi Rapid-Set.

  7. Long-term fluoride release from resin-reinforced orthodontic cements following recharge with fluoride solution

    Scientific Electronic Library Online (English)

    Rogério Lacerda dos, Santos; Matheus Melo, Pithon; Delmo Santiago, Vaitsman; Mônica Tirre de Souza, Araújo; Margareth Maria Gomes de, Souza; Matilde Gonçalves da Cunha, Nojima.

    Full Text Available O objetivo deste estudo foi testar a hipótese que não há diferença no desempenho dos cimentos de ionômero de vidro reforçados com resina entre si quanto à liberação de flúor antes e após recarga com flúor. Os materiais foram divididos em 5 grupos: 2 cimentos de ionômero de vidro reforçados com resin [...] a utilizados para cimentação de bandas ortodônticas: Grupo FOB (Fuji Ortho Band) e Grupo MCB (Multi-Cure Glass Ionomer Orthodontic Band Cement); 2 cimentos de ionômero de vidro reforçados com resina e 1 compósito utilizados para colagem de bráquetes ortodônticos: Grupo OGLC (Ortho Glass LC), Grupo FOLC (Fuji Ortho LC); e Grupo TXT (Transbond XT), respectivamente. A liberação de flúor foi medida durante 60 dias, através de eletrodo íon seletivo conectado a um analisador de íons. Após 4 semanas, os corpos de prova foram expostos a solução de fluoreto de sódio à 0,221%. Os resultados evidenciaram que os cimentos atingiram o pico máximo de liberação de flúor com 24 h após presa inicial. Não houve diferença estatisticamente significante entre a quantidade de flúor liberado após as recargas de fluoreto de sódio entre os grupos FOB e OGLC do 31° ao 36° dia (p>0.05). Concluindo os cimentos FOB e OGLC apresentaram maior capacidade de captação e liberação de flúor comparada aos outros CIVRRs. Abstract in english The aim of this study was to test the hypothesis that there is no difference in the fluoride release behavior of resin-reinforced glass ionomer cements before or after fluoride recharge. The materials were divided into 5 groups: 2 resin-reinforced glass ionomer cements used for attaching orthodontic [...] bands, that is, group FOB (Fuji Ortho Band) and group MCB (Multi-Cure Glass Ionomer Orthodontic Band Cement); 2 resin-reinforced glass ionomer cements and a composite used for bonding orthodontic brackets, that is, group OGLC (Ortho Glass LC), group FOLC (Fuji Ortho LC), and group TXT (Transbond XT), respectively. Fluoride release was measured during a 60-day period by using selective ion electrodes connected to an ionic analyser. After 4 weeks, the samples were exposed to 0.221% sodium fluoride solution. The results showed that cements achieved a maximum fluoride release 24 h after initial setting. No statistically significant differences were observed between groups FOB and OGLC regarding the amount of released fluoride following fluoride recharge from day 31 to day 36 (p>0.05). In conclusion, FOB and OGLC cements showed a higher capacity of capturing and releasing fluoride compared to the other cements studied.

  8. Effect of dental bleaching after bracket bonding and debonding using three different adhesive systems

    Scientific Electronic Library Online (English)

    Lucianna de Oliveira, Gomes; Paula, Mathias; Patricia, Rizzo; Telma Martins de, Araújo; Maria Cristina Teixeira, Cangussu.

    2013-04-01

    Full Text Available OBJETIVO: o objetivo desse estudo foi avaliar a influência da colagem e descolagem de braquetes ortodônticos no clareamento caseiro, considerando três diferentes sistemas adesivos. MÉTODOS: quarenta e quatro incisivos bovinos foram divididos em quatro grupos, de acordo com o sistema adesivo utilizad [...] o para colagem dos braquetes. Após a descolagem dos braquetes, os dentes foram pigmentados por 96 horas e depois clareados com peróxido de carbamida a 10% por 6 horas diárias, durante duas semanas. Foram realizadas fotografias digitais padronizadas nos tempos: T0 (inicial); T1 (após descolagem); T2 (após pigmentação); T3, T4 e T5 representando 1, 7 e 14 dias de clareamento. Testes de repetitividade e de estabilidade foram realizados para avaliar a acurácia do método. As imagens foram avaliadas pelo software Adobe Photoshop 7.0, considerando os parâmetros de cor (L*a*b*) e a diferença total de cor adaptada para esse estudo (?;E'). RESULTADOS: os resultados do presente estudo (ANOVA e Tukey; p Abstract in english OBJECTIVE: To evaluate the influence of bonding and debonding of orthodontic brackets on dental in-home bleaching, taking into account three different adhesive systems. METHODS: Forty-four bovine incisors were divided into four groups according to the primer system used for orthodontic bracket bondi [...] ng. Following the debonding of orthodontic brackets, the teeth were stored in staining solution for 96 hours. Then, teeth were whitened using 10% carbamide peroxide for two weeks at a 6-hour-a-day regime. Standardized digital photographs were taken at the following intervals: T0 (initial); T1 (after debonding); T2 (after pigmentation); T3, T4 and T5 representing 1, 7, and 14 days of bleaching. Repeatability and stability tests were carried out to check the method accuracy. Images were analyzed using Adobe Photoshop 7.0 software considering (L*a*b*)color coordinate values and a modified color difference total (?;E'). RESULTS: The results of this study (ANOVA and Tukey; p

  9. A força de atrito em braquetes plásticos e de aço inoxidável com a utilização de quatro diferentes tipos de amarração Frictional forces in stainless steel and plastic brackets using four types of wire ligation

    Directory of Open Access Journals (Sweden)

    Vanessa Nínia Correia Lima

    2010-04-01

    Full Text Available OBJETIVO: a finalidade deste estudo in vitro foi avaliar e comparar a resistência friccional em braquetes de aço inoxidável e de policarbonato compósito amarrados com fio metálico e elastômeros. MÉTODOS: foram utilizados quatro braquetes de aço inoxidável e quatro de policarbonato compósito (PC para pré-molares levados à máquina universal de ensaio mecânico para a tração de um segmento de fio de aço inoxidável 0,019" x 0,025" na velocidade de 0,5mm/min, com 8mm de deslocamento total. A forma de amarração variou entre as seguintes possibilidades: amarração metálica com pinça de Steiner, metálica com pinça Mathieu, elastômero da marca Morelli e elastômero da marca TP Orthodontics. RESULTADOS E CONCLUSÕES: os módulos elastoméricos geraram mais atrito do que os metálicos e a amarração com pinça Mathieu provocou menor atrito quando comparada a todas as situações avaliadas. Os braquetes de PC geraram menor atrito do que os metálicos, porém, na escolha do material a ser utilizado na clínica, outras variáveis - tais como a resistência ao cisalhamento e à fratura, a estabilidade de cor e a aderência por microrganismos - devem ser consideradas.OBJECTIVE: This in vitro study evaluated and compared the frictional resistance of stainless steel and polycarbonate (PC composite brackets tied with metal wire and elastomeric ligation. METHODS: Four stainless steel and four polycarbonate composite brackets for premolars were placed in a universal testing machine for the traction of a piece of 0.019 x 0.025-in wire at 0.5 mm/min and total displacement of 8 mm. Ligations were performed according to the following alternatives: metal ligation with Steiner tying pliers; metal ligation using Mathieu tying pliers; Morelli™ elastomeric ligation; and TP Orthodontics™ elastomeric ligation. RESULTS AND CONCLUSIONS: Elastomeric modules generated more friction than the metal ligations, and the ligation with the Mathieu tying pliers caused less friction than all the other conditions under study. PC brackets generated less friction than metal brackets, but the choice of material to be used in clinical conditions should take into consideration other variables, such as resistance to shearing and to fractures, as well as color stability and microorganism adherence.

  10. A força de atrito em braquetes plásticos e de aço inoxidável com a utilização de quatro diferentes tipos de amarração / Frictional forces in stainless steel and plastic brackets using four types of wire ligation

    Scientific Electronic Library Online (English)

    Vanessa Nínia Correia, Lima; Maria Elisa Rodrigues, Coimbra; Carla D' Agostini, Derech; Antônio Carlos de Oliveira, Ruellas.

    2010-04-01

    Full Text Available OBJETIVO: a finalidade deste estudo in vitro foi avaliar e comparar a resistência friccional em braquetes de aço inoxidável e de policarbonato compósito amarrados com fio metálico e elastômeros. MÉTODOS: foram utilizados quatro braquetes de aço inoxidável e quatro de policarbonato compósito (PC) par [...] a pré-molares levados à máquina universal de ensaio mecânico para a tração de um segmento de fio de aço inoxidável 0,019" x 0,025" na velocidade de 0,5mm/min, com 8mm de deslocamento total. A forma de amarração variou entre as seguintes possibilidades: amarração metálica com pinça de Steiner, metálica com pinça Mathieu, elastômero da marca Morelli e elastômero da marca TP Orthodontics. RESULTADOS E CONCLUSÕES: os módulos elastoméricos geraram mais atrito do que os metálicos e a amarração com pinça Mathieu provocou menor atrito quando comparada a todas as situações avaliadas. Os braquetes de PC geraram menor atrito do que os metálicos, porém, na escolha do material a ser utilizado na clínica, outras variáveis - tais como a resistência ao cisalhamento e à fratura, a estabilidade de cor e a aderência por microrganismos - devem ser consideradas. Abstract in english OBJECTIVE: This in vitro study evaluated and compared the frictional resistance of stainless steel and polycarbonate (PC) composite brackets tied with metal wire and elastomeric ligation. METHODS: Four stainless steel and four polycarbonate composite brackets for premolars were placed in a universal [...] testing machine for the traction of a piece of 0.019 x 0.025-in wire at 0.5 mm/min and total displacement of 8 mm. Ligations were performed according to the following alternatives: metal ligation with Steiner tying pliers; metal ligation using Mathieu tying pliers; Morelli™ elastomeric ligation; and TP Orthodontics™ elastomeric ligation. RESULTS AND CONCLUSIONS: Elastomeric modules generated more friction than the metal ligations, and the ligation with the Mathieu tying pliers caused less friction than all the other conditions under study. PC brackets generated less friction than metal brackets, but the choice of material to be used in clinical conditions should take into consideration other variables, such as resistance to shearing and to fractures, as well as color stability and microorganism adherence.

  11. In Vitro Properties of Orthodontic Adhesives with Fluoride or Amorphous Calcium Phosphate

    OpenAIRE

    Clara Ka Wai Chow; Christine D. Wu; Evans, Carla A.

    2011-01-01

    This in vitro study evaluated the efficacy of orthodontic adhesives with fluoride or amorphous calcium phosphate (ACP) in reducing bacterial adhesion and enamel demineralization. Forty human premolars each sectioned buccolingually into three parts were bracketed with control resin (Transbond XT) or adhesives containing ACP (Aegis Ortho) or fluoride (QuickCure). Artificial lesions induced by pH cycling were examined by X-ray photoelectron spectrophotometry (XPS) and polarized light microscopy ...

  12. Backscattering from dental restorations and splint materials during therapeutic radiation

    International Nuclear Information System (INIS)

    Models were constructed to simulate as closely as possible the human oral cavity. Radiation absorbed doses were determined for controls and various test situations involving the presence of dental restorative and splint materials during cobalt-60 irradiation of the models. Adjacent gold full crowns and adjacent solid dental silver amalgam cores both increased the dose to the interproximal gingivae by 20%. Use of orthodontic full bands for splinting the jaws increased the dose to the buccal tissues by an average of 10%. Augmentation of dose through backscatter radiation was determined to be only slight for intracoronal amalgam fillings and stainless steel or plastic bracket splints

  13. Comparison between two methods for resin removing after bracket debonding

    Scientific Electronic Library Online (English)

    Rodrigo De, Marchi; Luciana Manzotti De, Marchi; Raquel Sano Suga, Terada; Hélio Hissashi, Terada.

    2012-12-01

    Full Text Available OBJETIVO: o objetivo deste trabalho foi avaliar, por microscopia eletrônica de varredura, a eficácia de dois discos abrasivos de silicone e óxido de alumínio para a remoção da resina remanescente após a descolagem de braquetes ortodônticos. MÉTODOS: foram utilizados 10 dentes bovinos selecionados al [...] eatoriamente, sendo 2 para o grupo controle e os demais divididos em dois grupos, os quais receberam colagem de braquetes ortodônticos com resina ortodôntica Concise (3M). Os métodos de remoção da resina após a descolagem dos acessórios ortodônticos em apenas uma etapa foram: Grupo A - disco Optimize (TDV); e Grupo B - disco Onegloss (Shofu), empregados em baixa rotação. Após a remoção da resina remanescente pelos métodos mencionados, os dentes foram preparados para serem submetidos à análise em microscopia eletrônica de varredura, obtendo-se fotografias da superfície do esmalte com aumento de 50X. Seis examinadores avaliaram as fotografias seguindo a escala de avaliação de Zachrisson e Arthun (1979). RESULTADOS: no Grupo A, observou-se pequenos arranhões na superfície do esmalte, bem como pouco remanescente de resina em algumas das fotografias; enquanto, no Grupo B, observou-se maior lisura, pouco ou nenhum remanescente de resina e alguns riscos nas fotografias. Não houve diferença estatisticamente significativa entre os dois métodos avaliados e o grupo controle. CONCLUSÃO: os dois discos abrasivos mostraram-se eficientes para remoção da resina remanescente após a descolagem de braquete em única etapa. Abstract in english OBJECTIVE: The aim of this study was to assess - using scanning electron microscopy (SEM) - the effectiveness of two abrasive discs, one made from silicon and one from aluminum oxide, in removing adhesive remnants (AR) after debonding orthodontic brackets. METHODS: Ten randomly selected bovine teeth [...] were used, i.e., 2 in the control group, and the other 8 divided into two groups, which had orthodontic brackets bonded to their surface with Concise Orthodontic Adhesive (3M). The following methods were employed - in one single step - to remove AR after debracketing: Group A, Optimize discs (TDV) and Group B, Onegloss discs (Shofu), used at low speed. After removing the AR with the aforementioned methods, the teeth were prepared to undergo SEM analysis, and photographs were taken of the enamel surface with 50x magnification. Six examiners evaluated the photographs applying the Zachrisson and Årtun enamel surface index (ESI) system (1979). RESULTS: Group A exhibited minor scratches on the enamel surface as well as some AR in some of the photographs, while Group B showed a smoother surface, little or no AR and some abrasion marks in the photographs. No statistically significant differences were found between the two methods and the control group. CONCLUSIONS: The two abrasive discs were effective in removing the AR after bracket debonding in one single step.

  14. Evaluation of Subgingival Dental Plaque Microbiota Changes In Fixed Orthodontic Patients with Syber Green Real Time PCR

    Directory of Open Access Journals (Sweden)

    Naser Sargolzaie

    2014-06-01

    Full Text Available Introduction: One of the most common problems we confront in orthodontic therapy is periodontal diseases. Initial factor which causes these diseases is colonization of anaerobic microorganisms in subgingival plaque. Technically, local environmental changes related to orthodontic band and brackets may influence the bacterial species in periodontal plaque. However, it seems necessary to assess variations in subgingival plaque caused by orthodontic appliances. The aim of this study was to investigate changes in subgingival microbiota and clinical parameters before and after bracket placement. Methods: Clinical parameters including probing depth (PD, plaque index (PI, clinical attachment level (CAL, bleeding on probing (BOP and gingival index (GI were recorded and subgingival microbial samples were collected in 30 people aged between 13 and 25. As a control group, 15 persons getting matched as to their age and sex with no need to orthodontic treatment were opted using specific primers, SYBER Green Real-Time PCR was carried out in order to determine bacterial flora in stored samples. All mentioned procedures were reassessed in experimental group and in control group three months after band and bracket bonding. A descriptive analysis was conducted, and paired t test and Wilcoxon test were used for differences between groups (P

  15. Laser Guided Automated Calibrating System for Accurate Bracket Placement

    Science.gov (United States)

    Anitha, A; Kumar, AJ; Mascarenhas, R; Husain, A

    2015-01-01

    Background: The basic premise of preadjusted bracket system is accurate bracket positioning. It is widely recognized that accurate bracket placement is of critical importance in the efficient application of biomechanics and in realizing the full potential of a preadjusted edgewise appliance. Aim: The purpose of this study was to design a calibrating system to accurately detect a point on a plane as well as to determine the accuracy of the Laser Guided Automated Calibrating (LGAC) System. Materials and Methods: To the lowest order of approximation a plane having two parallel lines is used to verify the accuracy of the system. On prescribing the distance of a point from the line, images of the plane are analyzed from controlled angles, calibrated and the point is identified with a laser marker. Results: The image was captured and analyzed using MATLAB ver. 7 software (The MathWorks Inc.). Each pixel in the image corresponded to a distance of 1cm/413 (10 mm/413) = 0.0242 mm (L/P). This implies any variations in distance above 0.024 mm can be measured and acted upon, and sets the highest possible accuracy for this system. Conclusion: A new automated system is introduced having an accuracy of 0.024 mm for accurate bracket placement. PMID:25745575

  16. Motivations and future practice plans of orthodontic residents in Saudi Arabia

    OpenAIRE

    Al-Hamlan, Nasir; Al-Ruwaithi, Moatazbellah M.; Al-Shraim, Nasir; El-Metwaaly, Ashraf

    2013-01-01

    Aims: This study aims to explore the criteria used by graduate students while selecting a career as orthodontists and their future aspirations. Materials and Methods: A list of Saudi Board of Orthodontics (SB-Ortho) residents was obtained from the Central and Western regions of the Kingdom and all orthodontic residents (excluding the 1st year residents) were invited to participate in this survey. Permission to contact the orthodontic residents was obtained from the respective program director...

  17. Mechanical properties of orthodontic wires made of super engineering plastic.

    Science.gov (United States)

    Maekawa, Minami; Kanno, Zuisei; Wada, Takahiro; Hongo, Toshio; Doi, Hisashi; Hanawa, Takao; Ono, Takashi; Uo, Motohiro

    2015-01-01

    Most orthodontic equipment is fabricated from alloys such as stainless steel, Co-Cr and Ni-Ti because of their excellent elastic properties. In recent years, increasing esthetic demands, metal allergy and interference of metals with magnetic resonance imaging have driven the development of non-metallic orthodontic materials. In this study, we assessed the feasibility of using three super engineering plastics (PEEK, PES and PVDF) as orthodontic wires. PES and PVDF demonstrated excellent esthetics, although PEEK showed the highest bending strength and creep resistance. PEEK and PVDF showed quite low water absorption. Because of recent developments in coloration of PEEK, we conclude that PEEK has many advantageous properties that make it a suitable candidate for use as an esthetic metal-free orthodontic wire. PMID:25748467

  18. [Gingival recessions and orthodontics].

    Science.gov (United States)

    Renkema, A M; Padmos, J A D; de Quincey, G de

    2015-11-01

    Gingival recessions represent the most visible periodontal disease. The prevalence of gingival recessions is high. The root surface is literally exposed to negative influences such as erosion, abrasion, discoloration and decay. Moreover, gingival recessions can affect the quality of life by increased thermal sensitivity and reduced dento-gingival aesthetics. The aetiology of gingival recessions is complex and considered to be multifactorial. In order to prevent the development of gingival recessions during and after orthodontic treatment, several factors should be taken into account, among which maintenance of optimal oral hygiene and respect for the 'biological envelope' are decisive. Once gingival recessions have developed, orthodontic therapy can play a positive role in their treatment. PMID:26569002

  19. Orthodontic scanners: what's available?

    Science.gov (United States)

    Martin, Catherine B; Chalmers, Elsinore V; McIntyre, Grant T; Cochrane, Heather; Mossey, Peter A

    2015-06-01

    The popularity and availability of virtual technology in orthodontics for the replacement of hard-copy records with electronic records is growing rapidly, with a move towards a 'digital' patient for diagnosis, treatment planning, monitoring of treatment progress and outcome. As part of this ongoing development, three-dimensional digital models of the dental arches have the potential to replace traditional plaster models and their associated limitations for treatment planning, appliance construction and simulated treatment outcomes. This article provides the reader with a summary of the currently available benchtop model scanners and intraoral scanners. It is likely that this technology will become increasingly common-place within the orthodontic profession over the next decade. PMID:25939980

  20. Evaluation of enamel surface after bracket debonding and polishing Avaliação da superfície do esmalte dentário após a remoção do braquete e polimento

    OpenAIRE

    Lilian Maria Brisque Pignatta; Sillas Duarte Júnior; Eduardo César Almada Santos

    2012-01-01

    INTRODUCTION: Preserving the dental enamel structure during removal of orthodontic accessories is a clinician's obligation. Hence the search for an evidence based debonding protocol. OBJECTIVE: to evaluate and compare, by means of scanning electron microscopy (SEM), the effects of four different protocols of bracket debonding and subsequent polishing on enamel surface, and to propose a protocol that minimizes damage to enamel surface. METHODS: Twelve bovine permanent incisors were divided int...

  1. Heat Exchanger Support Bracket Design Calculations

    Energy Technology Data Exchange (ETDEWEB)

    Rucinski, Russ; /Fermilab

    1995-01-12

    This engineering note documents the design of the heat exchanger support brackets. The heat exchanger is roughly 40 feet long, 22 inches in diameter and weighs 6750 pounds. It will be mounted on two identical support brackets that are anchored to a concrete wall. The design calculations were done for one bracket supporting the full weight of the heat exchanger, rounded up to 6800 pounds. The design follows the American Institute of Steel Construction (AISC) Manual of steel construction, Eighth edition. All calculated stresses and loads on welds were below allowables.

  2. Hausdorff Distance evaluation of orthodontic accessories' streaking artifacts in 3D model superimposition

    Directory of Open Access Journals (Sweden)

    José Rino Neto

    2012-10-01

    Full Text Available The aim of this study was to determine whether image artifacts caused by orthodontic metal accessories interfere with the accuracy of 3D CBCT model superimposition. A human dry skull was subjected three times to a CBCT scan: at first without orthodontic brackets (T1, then with stainless steel brackets bonded without (T2 and with orthodontic arch wires (T3 inserted into the brackets' slots. The registration of image surfaces and the superimposition of 3D models were performed. Within-subject surface distances between T1-T2, T1-T3 and T2-T3 were computed and calculated for comparison among the three data sets. The minimum and maximum Hausdorff Distance units (HDu computed between the corresponding data points of the T1 and T2 CBCT 3D surface images were 0.000000 and 0.049280 HDu, respectively, and the mean distance was 0.002497 HDu. The minimum and maximum Hausdorff Distances between T1 and T3 were 0.000000 and 0.047440 HDu, respectively, with a mean distance of 0.002585 HDu. In the comparison between T2 and T3, the minimum, maximum and mean Hausdorff Distances were 0.000000, 0.025616 and 0.000347 HDu, respectively. In the current study, the image artifacts caused by metal orthodontic accessories did not compromise the accuracy of the 3D model superimposition. Color-coded maps of overlaid structures complemented the computed Hausdorff Distances and demonstrated a precise fusion between the data sets.

  3. Technical report for quality requirements establishment of in-chimney bracket

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Kwan Hyun

    2000-06-01

    This technical report provides the methods on how to sustain the items of experimental materials, nuclear fuel on examination, ect. This report applies to the quality assurance(QA) programmes of the design, fabrication in-chimney bracket.The organization having overall responsibility for the nuclear power item design, preservation, fabrication shall be described in this report in each stage of chimney bracket fabrication project.

  4. Orthodontics Align Crooked Teeth and Boost Self-Esteem

    Science.gov (United States)

    ... desktop! more... Orthodontics Align Crooked Teeth and Boost Self- esteem Article Chapters Orthodontics Align Crooked Teeth and Boost Self- esteem Orthodontics print full article print this chapter email ...

  5. Rapid orthodontics with alveolar reshaping: two case reports of decrowding.

    Science.gov (United States)

    Wilcko, W M; Wilcko, T; Bouquot, J E; Ferguson, D J

    2001-02-01

    Two case reports demonstrate a new orthodontic method that offers short treatment times and the ability to simultaneously reshape and increase the buccolingual thickness of the supporting alveolar bone. A 24-year-old man with a Class I severely crowded malocclusion and an overly constricted maxilla with concomitant posterior crossbites and a 17-year-old female with a Class I moderately to severely crowded malocclusion requested shortened orthodontic treatment times. This new surgery technique included buccal and lingual full-thickness flaps, selective partial decortication of the cortical plates, concomitant bone grafting/augmentation, and primary flap closure. Following the surgery, orthodontic adjustments were made approximately every 2 weeks. From bracketing to debracketing, both cases were completed in approximately 6 months and 2 weeks. Posttreatment evaluation of both patients revealed good results. At approximately 15 months following surgery in one patient, a full-thickness flap was again reflected. Visual examination revealed good maintenance of the height of the alveolar crest and an increased thickness in the buccal bone. The canine and premolars in this area were expanded buccally by more than 3 mm, and yet there had actually been an increase in the buccolingual thickness of the overlying buccal bone. Additionally, a preexisting bony fenestration buccal of the root of the first premolar was covered. Both of these findings lend credence to the incorporation of the bone augmentation procedure into the corticotomy surgery because this made it possible to complete the orthodontic treatment with a more intact periodontium. The rapid expansive tooth movements with no significant apical root resorption may be attributed to the osteoclastic or catabolic phase of the regional acceleratory phenomenon. Instead of bony "block" movement or resorption/apposition, the degree of demineralization/remineralization might be a more accurate explanation of what occurs in the alveolar bone during physiologic tooth movement in these patients. PMID:11829041

  6. Poisson Bracket on the Space of Histories

    CERN Document Server

    Marolf, D

    1994-01-01

    We extend the Poisson bracket from a Lie bracket of phase space functions to a Lie bracket of functions on the space of canonical histories and investigate the resulting algebras. Typically, such extensions define corresponding Lie algebras on the space of Lagrangian histories via pull back to a space of partial solutions. These are the same spaces of histories studied with regard to path integration and decoherence. Such spaces of histories are familiar from path integration and some studies of decoherence. For gauge systems, we extend both the canonical and reduced Poisson brackets to the full space of histories. We then comment on the use of such algebras in time reparameterization invariant systems and systems with a Gribov ambiguity, though our main goal is to introduce concepts and techniques for use in a companion paper.

  7. New classical brackets for dissipative systems

    CERN Document Server

    Bimonte, G; Marmo, G; Stornaiolo, C

    2003-01-01

    A set of brackets for classical dissipative systems, subject to external random forces, are derived. The method is inspired to the old procedure found by Peierls, for deriving the canonical brackets of conservative systems, starting from an action principle. It is found that an adaptation of Peierls' method is applicable also to dissipative systems, when the friction term can be described by a linear functional of the coordinates, as is the case in the classical Langevin equation, with an arbitrary memory function. The general expression for the brackets satisfied by the coordinates, as well as by the external random forces, at different times, is determined, and it turns out that they all satisfy the Jacobi identity. Upon quantization, these classical brackets are found to coincide with the commutation rules for the quantum Langevin equation, that have been obtained in the past, by appealing to microscopic conservative quantum models for the friction mechanism.

  8. Linear odd Poisson bracket on Grassmann variables

    International Nuclear Information System (INIS)

    A linear odd Poisson bracket (antibracket) realized solely in terms of Grassmann variables is suggested. It is revealed that the bracket, which corresponds to a semi-simple Lie group, has at once three Grassmann-odd nilpotent ?-like differential operators of the first, the second and the third orders with respect to Grassmann derivatives, in contrast with the canonical odd Poisson bracket having the only Grassmann-odd nilpotent differential ?-operator of the second order. It is shown that these ?-like operators together with a Grassmann-odd nilpotent Casimir function of this bracket form a finite-dimensional Lie superalgebra. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved.)

  9. Interrelationships of endodontic- orthodontic treatments

    Directory of Open Access Journals (Sweden)

    Khedmat S

    2005-05-01

    Full Text Available The purpose of this article was reviewing the literature related to the mutual effects of endodontics and orthodontics on each other providing documented information that can be used by dentists in clinical practice. The effect of orthodontic treatment on the dental pulp and its role in root resorption, the influence of previous trauma to the tooth and endodontic treatment in orthodontic tooth movements and root resorption, recommendations regarding endodontic treatment during orthodontic tooth movement and the role of the orthodontic forces in provision and outcome of endodontic treatment are being discussed. The effect of the orthodontic tooth movement on the pulp is focused primarily on the neurovascular system which can cause degenerative and/or inflammatory responses in the dental pulp. Although, most of these changes are considered reversible, it seems that teeth with complete apical foramen and teeth subjected to previous insults, such as trauma, caries, restorations and periodontal diseases are more susceptible to pulpal irreversible changes. Teeth with root canal treatment that are well cleaned shaped, and three- dimensionally obturated, exhibit less propensity to apical root resorption during orthodontic tooth movement. This outcome depends on the absence of microleakage for bacterial ingress. A traumatized tooth can be moved orthodontically with minimal risk of resorption, provided that the pulp has not been severely injured (infection or necrosis. If there is evidence of pulpal demise, appropriate endodontic treatment is necessary prior to orthodontic treatment .If a previously traumatized tooth exhibits resorption, there is a greater chance that orthodontic tooth movement will enhance the resorptive process. If a tooth has been severely traumatized (intrusion, avulsion there would be a greater incidence of resorption with tooth movement. It is recommended that teeth requiring root canal treatment during orthodontic movement be initially cleaned and shaped followed by the interim placement of calcium hydroxide. Final canal obturation with gutta-percha should be accomplished upon the completion of orthodontic treatment. Endodontically treated teeth can be moved orthodontically similar to teeth with vital pulps. In case of endodontic procedures like apexification, there may be no need to delay the orthodontic treatment.

  10. Evaluation of frictional forces between ceramic brackets and archwires of different alloys compared with metal brackets

    Directory of Open Access Journals (Sweden)

    Ariana Pulido Guerrero

    2010-03-01

    Full Text Available The aim of this study was to evaluate, in vitro, frictional forces produced by ceramic brackets and arch wires of different alloys. Frictional tests were performed on three ceramic brackets: monocrystalline (Inspire ICE, polycrystalline (InVu, polycrystalline with metal slot (Clarity, and one stainless steel bracket (Dyna-Lock. Thirty brackets of each were tested, all with .022" slots, in combination with stainless steel and nickel-titanium wires .019" × .025", at 0° and 10° angulation, in artificial saliva. Arch wires were pulled through the slots at a crosshead speed of 10 mm/min. There were statistically significant differences between the groups of brackets and wires studied (p < .05. The polycrystalline brackets with metal slots had values similar to those of conventional polycrystalline brackets, and the monocrystalline brackets had the highest frictional forces. The nickel-titanium wires produced the lowest friction. The addition of metal slots in the polycrystalline brackets did not significantly decrease frictional values. Nickel-titanium wires produced lower friction than those of stainless steel.

  11. Mechanical properties of one and two-step fluoridated orthodontic resins submitted to different pH cycling regimes

    Directory of Open Access Journals (Sweden)

    Paula Passalini

    2010-06-01

    Full Text Available The aim of this study is to assess the in vitro shear bond strength and adhesive remnant index (ARI of one and two-step fluoridated orthodontic resins under conditions that simulate high cariogenic challenge. Edgewise brackets for maxillary central incisors were randomly bonded to 80 bovine incisors, using either TransbondTM Plus Color Change orthodontic resin and a self-etching primer adhesive (G1; n = 40 or Orthodontic Fill Magic with a conventional acid-etch technique (G2; n = 40. Each group of resin (n = 10 was divided into: immediate shear (A- pre-cycling control, immersion in artificial remineralizing saliva (neutral saliva for 14 days (B- post-cycling control and pH cycling with high cariogenic challenge (C- acid saliva with pH 5.5 and D- acid saliva with pH 4.5. After 14 days of pH cycling, the shear bond strength and ARI were evaluated. Considering the shear bond strength, TransbondTM Plus Color Change resin was stronger than Orthodontic Fill Magic when it was submitted to high cariogenic challenge (p < 0.05. Also TransbondTM Plus Color Change resin showed better adhesion to enamel than Orthodontic Fill Magic, in all situations evaluated (p < 0.05. It could be concluded that TransbondTM Plus Color Change resin presented better shear bond strength and adhesive remnant index when submitted to high cariogenic challenge, in comparison with Orthodontic Fill Magic.

  12. Influence of in vitro pigmenting of esthetic orthodontic ligatures on smile attractiveness

    Directory of Open Access Journals (Sweden)

    Camila Ferraz

    2012-10-01

    Full Text Available OBJECTIVE: To evaluate the perception of dental students and orthodontists on the degree of influence that pigmented esthetic elastic ligatures have on smile attractiveness, by judging clinical photographs. METHODS: Sixteen clinical facial photographs of the smile and 16 close up images of the smile of a single patient wearing monocrystalline porcelain orthodontic brackets, Teflon coated NiTi wire brackets and esthetic elastic ligatures of five different commercial brands were distributed into eight groups, G1 to G8 (Morelli®, Ortho Tecnology™, TP Orthodontics™, Unitek/3M™clear, Unitek/3M™ obscure, American Orthodontics™ clear, American Orthodontics™ pearl and American Orthodontics™ metallic pearl. Twenty ligatures were used in each group, totaling 160 ligatures. Half of them were used in their natural state, and the other half after in vitro pigmentation. All the photographs were judged by 40 evaluators, 20 orthodontists and 20 dental students. RESULTS: For orthodontists, American™ pearl (G7 ligatures were those that least influenced the degree of attractiveness of the smile in the two types of photographs used. For the dental students, in the facial photographs of the smile, ligatures with the best performance were Morelli® (G1, American™ clear (G6 and American™ pearl (G7 and in the close up photographs of the smile, American™ pearl, metallic pearl and clear (G7, G8 and G6. CONCLUSIONS: For both orthodontists and dental students, pigmentation of the elastic ligatures had a negative influence on the degree of attractiveness of smiles in the two types of clinical photographs evaluated.OBJETIVO: avaliar, através de fotografias clínicas, entre estudantes de Odontologia e ortodontistas, o grau de influência que ligaduras elásticas estéticas pigmentadas exercem sobre a atratividade do sorriso. MÉTODOS: foram utilizadas 16 fotografias clínicas faciais do sorriso e 16 de sorriso aproximado de um único paciente portando braquetes ortodônticos de porcelana monocristalina, fio de NiTi teflonado e ligaduras elásticas estéticas de cinco marcas comerciais diferentes, distribuídas em oito grupos, G1 a G8 (Morelli, Ortho Technology, TP Orthodontics, 3M/Unitek clear, 3M/Unitek obscure, American Orthodontics clear, American Orthodontics pearl e American Orthodontics metalic pearl. Foram utilizadas 20 ligaduras de cada grupo, totalizando 160 ligaduras. Metade delas foi utilizada em estado natural e a outra metade após pigmentação in vitro. Todas as fotografias foram julgadas por 40 avaliadores, sendo 20 ortodontistas e 20 estudantes de Odontologia. RESULTADOS: para ortodontistas, as ligaduras American Orthodontics pearl (G7 foram as que menos influenciaram o grau de atratividade do sorriso nos dois tipos de fotografias utilizadas. Para os estudantes de Odontologia, nas fotografias faciais do sorriso, as que obtiveram o melhor desempenho foram Morelli (G1, American Orthodontics clear (G6 e American Orthodontics pearl (G7 e, nas fotografias de sorriso aproximado, American Orthodontics pearl, metalic pearl e clear (G7, G8 e G6, respectivamente. CONCLUSÕES: tanto para ortodontistas quanto para estudantes de Odontologia, a pigmentação das ligaduras elásticas influenciou de forma negativa o grau de atratividade dos sorrisos nos dois tipos de fotografias clínicas avaliadas.

  13. Influence of in vitro pigmenting of esthetic orthodontic ligatures on smile attractiveness

    Scientific Electronic Library Online (English)

    Camila, Ferraz; Marcelo, Castellucci; Márcio, Sobral.

    2012-10-01

    Full Text Available OBJETIVO: avaliar, através de fotografias clínicas, entre estudantes de Odontologia e ortodontistas, o grau de influência que ligaduras elásticas estéticas pigmentadas exercem sobre a atratividade do sorriso. MÉTODOS: foram utilizadas 16 fotografias clínicas faciais do sorriso e 16 de sorriso aproxi [...] mado de um único paciente portando braquetes ortodônticos de porcelana monocristalina, fio de NiTi teflonado e ligaduras elásticas estéticas de cinco marcas comerciais diferentes, distribuídas em oito grupos, G1 a G8 (Morelli, Ortho Technology, TP Orthodontics, 3M/Unitek clear, 3M/Unitek obscure, American Orthodontics clear, American Orthodontics pearl e American Orthodontics metalic pearl). Foram utilizadas 20 ligaduras de cada grupo, totalizando 160 ligaduras. Metade delas foi utilizada em estado natural e a outra metade após pigmentação in vitro. Todas as fotografias foram julgadas por 40 avaliadores, sendo 20 ortodontistas e 20 estudantes de Odontologia. RESULTADOS: para ortodontistas, as ligaduras American Orthodontics pearl (G7) foram as que menos influenciaram o grau de atratividade do sorriso nos dois tipos de fotografias utilizadas. Para os estudantes de Odontologia, nas fotografias faciais do sorriso, as que obtiveram o melhor desempenho foram Morelli (G1), American Orthodontics clear (G6) e American Orthodontics pearl (G7) e, nas fotografias de sorriso aproximado, American Orthodontics pearl, metalic pearl e clear (G7, G8 e G6, respectivamente). CONCLUSÕES: tanto para ortodontistas quanto para estudantes de Odontologia, a pigmentação das ligaduras elásticas influenciou de forma negativa o grau de atratividade dos sorrisos nos dois tipos de fotografias clínicas avaliadas. Abstract in english OBJECTIVE: To evaluate the perception of dental students and orthodontists on the degree of influence that pigmented esthetic elastic ligatures have on smile attractiveness, by judging clinical photographs. METHODS: Sixteen clinical facial photographs of the smile and 16 close up images of the smile [...] of a single patient wearing monocrystalline porcelain orthodontic brackets, Teflon coated NiTi wire brackets and esthetic elastic ligatures of five different commercial brands were distributed into eight groups, G1 to G8 (Morelli®, Ortho Tecnology™, TP Orthodontics™, Unitek/3M™clear, Unitek/3M™ obscure, American Orthodontics™ clear, American Orthodontics™ pearl and American Orthodontics™ metallic pearl). Twenty ligatures were used in each group, totaling 160 ligatures. Half of them were used in their natural state, and the other half after in vitro pigmentation. All the photographs were judged by 40 evaluators, 20 orthodontists and 20 dental students. RESULTS: For orthodontists, American™ pearl (G7) ligatures were those that least influenced the degree of attractiveness of the smile in the two types of photographs used. For the dental students, in the facial photographs of the smile, ligatures with the best performance were Morelli® (G1), American™ clear (G6) and American™ pearl (G7) and in the close up photographs of the smile, American™ pearl, metallic pearl and clear (G7, G8 and G6). CONCLUSIONS: For both orthodontists and dental students, pigmentation of the elastic ligatures had a negative influence on the degree of attractiveness of smiles in the two types of clinical photographs evaluated.

  14. Evaluation of frictional forces between ceramic brackets and archwires of different alloys compared with metal brackets

    Scientific Electronic Library Online (English)

    Ariana Pulido, Guerrero; Odilon, Guariza Filho; Orlando, Tanaka; Elisa Souza, Camargo; Sérgio, Vieira.

    2010-03-01

    Full Text Available The aim of this study was to evaluate, in vitro, frictional forces produced by ceramic brackets and arch wires of different alloys. Frictional tests were performed on three ceramic brackets: monocrystalline (Inspire ICE), polycrystalline (InVu), polycrystalline with metal slot (Clarity), and one sta [...] inless steel bracket (Dyna-Lock). Thirty brackets of each were tested, all with .022" slots, in combination with stainless steel and nickel-titanium wires .019" × .025", at 0° and 10° angulation, in artificial saliva. Arch wires were pulled through the slots at a crosshead speed of 10 mm/min. There were statistically significant differences between the groups of brackets and wires studied (p

  15. Orthodontic Microimplants Assisted Intrusion of Supra-erupted Maxillary Molar Enabling Osseointegrated Implant Supported Mandibular Prosthesis: Case Reports.

    Science.gov (United States)

    Rai, Deepak; Bhasin, Saranjeet Singh; Rai, Sheetal

    2014-12-01

    Loss of mandibular molars, when not replaced in time, are usually associated with overeruption of maxillary molars. To provide prosthetic replacement for missing lower posteriors, over erupted maxillary teeth have been intruded in past with great difficulty in adults with conventional orthodontics, along with associated problems of root resorption. Currently orthodontic microimplants provide stable intraoral anchorage, allow predictable maxillary molar intrusion enabling reestablishment of functional posterior occlusion with mandibular implant supported prosthesis, thereby reducing need for prosthetic crown reduction in maxillary arch. The added advantage of microimplant is it enables use of sectional appliance in area of concern instead of full arch bracketed appliance which an adult may not accept. The case reports demonstrates, overerupted maxillary molars were intruded using orthodontic microimplants to enable prosthetic rehabilitation of mandibular dentition by osseointegrated implant supported prosthesis. The second case report also demonstrates use of CBCT scan in planning and execution. PMID:26199523

  16. Temporary Anchorage Devices in Orthodontics

    Directory of Open Access Journals (Sweden)

    Gowri Sankar Singaraju

    2009-07-01

    Full Text Available Anchorage control is one of the main aspects of orthodontic treatment plan. A good appliance system should put minimum taxation of anchorage on the anchor units. The structures present with in the confinement of oral cavity are very less in number. In such cases the anchor unit gets its reinforcement from extraoral structures or intraoral appliances. Extraoral anchorages have their inherent drawbacks and most of them rely on patient cooperation. The use of implants in orthodontics to reinforce the anchorage is a recent concept. The purpose of this article is to review the implants in the context of orthodontics which are called as TAD- temporary anchorage devices.

  17. Opening and closure forces of sliding mechanisms of different self-ligating brackets

    Scientific Electronic Library Online (English)

    Paola, GANDINI; Linda, ORSI; Maria Francesca, SFONDRINI; Andrea, SCRIBANTE.

    2013-06-01

    Full Text Available Self-ligating brackets engage the wire by means of a slide mechanism. Forces that have to be applied to open and close the sliding mechanism of brackets are still unknown. Objective The aim of this study was to measure and compare the opening and closure forces of different self-ligating b [...] rackets. Material and Methods Three different stainless steel self-ligating brackets (Carriere LX, Ortho Organizers; F1000, Leone; Damon Q, Ormco) were tested. For each different bracket, 20 maxillary right central incisors and 20 mandibular right central incisors were used. Opening and closure forces were measured using an Instron Universal Testing Machine. Statistical analysis was performed and ANOVA and Tukey tests were carried out. Results Opening forces were registered between 1.1 N and 5.6 N, whereas closure forces were recorded between 1.57 N and 4.87 N. Significant differences were detected among the different brackets and between the two prescriptions tested. Conclusion The knowledge of different opening and closure forces of self-ligating brackets can help the orthodontist in the clinical management of these devices.

  18. Awareness of Orthodontic Treatments among School Teachers of Two Cities in Iran

    Directory of Open Access Journals (Sweden)

    Ali Rafighi

    2012-02-01

    Full Text Available Background and aims. Since most orthodontic patients are children and adolescents, it is believed that teachers can help find these patients and make them aware of their orthodontic problems. Therefore, teachers are expected to have proper knowledge about these problems. The aim of this study was to determine teachers’ awareness about orthodontic treatments in Tabriz and Saqqez and compare it in different educational levels. Materials and methods. A questionnaire was given to 384 teachers (204 in Tabriz and 180 in Saqqez in randomly selected schools of different levels. The questionnaire had 17 questions in 3 sections, including general information, age, and costs of orthodontic treatments. The teachers’ awareness in two cities was analyzed with independent t-test and in educational levels with one-way ANOVA. Results. About 94% of the participants believed orthodontic treatment consisted of arrangement of teeth with special braces. However, there was no significant difference between the two cities in general information (p=0.23 and the age suitable for orthodontic treatment (p=0.53. The differences in the teachers’ awareness in three educational levels were not statistically significant between the two cities (p=0.23. Conclusion. Awareness of teachers about orthodontic treatment in Saqqez and Tabriz was not sufficient and different; 75% of the participants believed that high cost of orthodontic treatment is the main problem.

  19. Immunosuppressants: implications in Orthodontics

    Scientific Electronic Library Online (English)

    Rogério Lacerda dos, Santos; Maria Cláudia Mesquita, Lacerda; Renato Torres, Gonçalves; Marco Aurélio, Martins; Margareth Maria Gomes de, Souza.

    2012-04-01

    Full Text Available INTRODUCTION: There are medications capable of affecting bone metabolism and the rate of tooth movement. Among these medications are the immunosuppressants, which act by repressing the action of T lymphocytes, however they can cause bone loss and consequently lead to osteoporosis. Osteoporosis is a [...] common complication following kidney, heart, liver or lung transplantation. The immunosuppressant treatment for preventing organ rejection after transplantation, in general, includes glucocorticoids, cyclosporine, tacrolimus, and sirolimus. All these drugs can have jeopardizing effects on bone mineral homeostasis and consequently influence tooth movement. In recent years, however, the increasing use of immunosuppressants has raised questions about their effects on bone metabolism in patients undergoing orthodontic treatment. OBJECTIVE: The objective of this review study was to inform orthodontists about the influence of immunosuppressants on bone metabolism and tooth movement.

  20. Immunosuppressants: implications in Orthodontics

    Directory of Open Access Journals (Sweden)

    Rogério Lacerda dos Santos

    2012-04-01

    Full Text Available INTRODUCTION: There are medications capable of affecting bone metabolism and the rate of tooth movement. Among these medications are the immunosuppressants, which act by repressing the action of T lymphocytes, however they can cause bone loss and consequently lead to osteoporosis. Osteoporosis is a common complication following kidney, heart, liver or lung transplantation. The immunosuppressant treatment for preventing organ rejection after transplantation, in general, includes glucocorticoids, cyclosporine, tacrolimus, and sirolimus. All these drugs can have jeopardizing effects on bone mineral homeostasis and consequently influence tooth movement. In recent years, however, the increasing use of immunosuppressants has raised questions about their effects on bone metabolism in patients undergoing orthodontic treatment. OBJECTIVE: The objective of this review study was to inform orthodontists about the influence of immunosuppressants on bone metabolism and tooth movement.

  1. Orthodontic mechanics using mini-implant measured by FBG

    Science.gov (United States)

    Trannin, Pamela G.; Milczewski, Maura S.; de Oliveira, Walmir; Guariza Filho, Odilon; Lopes, Stephani C. P. S.; Kalinowski, Hypolito J.

    2015-07-01

    The magnitude of the force generated during orthodontic mechanics anchored in mini-implant in a maxilla model was analyzed. Data was collected during the insertion of the mini-implant and at the moment of applying forces to the structure of the maxilla and dentition. To obtain quantitative results, the Fibre Bragg Gratings (FBG) were inserted in an elastomeric material reproducing a maxilla model. It was observed levels of forces of approximately 3,78N next to the root of first premolar by the insertion of the mini-implant and different levels of the force to different orthodontic mechanics applied on the dental system.

  2. Friction in orthodontics.

    Science.gov (United States)

    Prashant, P S; Nandan, Hemant; Gopalakrishnan, Meera

    2015-08-01

    Conventional wisdom suggests that resistance to sliding (RS) generated at the wire-bracket interface has a bearing on the force transmitted to the teeth. The relative importance of static and kinetic friction and also the effect of friction on anchorage has been a topic of debate. Lot of research work has been done to evaluate the various factors that affect friction and thus purportedly retards the rate of tooth movement. However, relevancy of these studies is questionable as the methodology used hardly simulates the oral conditions. Lately studies have concluded that more emphasis should be laid on binding and notching of archwires as these are considered to be the primary factors involved in retarding the tooth movement. This article reviews the various components involved in RS and the factors affecting friction. Further, research work should be carried out to provide cost effective alternatives aimed at reducing friction. PMID:26538873

  3. Bonded Bracket Assmebly for Frameless Solar Panels

    Energy Technology Data Exchange (ETDEWEB)

    Murray, Todd [Rayce Americas, Auburn Hills, MI (United States); Jackson, Nick [Rayce Americas, Auburn Hills, MI (United States); Dupont, Luc [ARaymond Tinnerman Industries, Inc., Brunswick, OH (United States); Moser, Jeff [ARaymond Tinnerman Industries, Inc., Brunswick, OH (United States)

    2013-01-30

    In February 2011 the US Department of Energy announced their new Sunshot Initiative. The Sunshot goal is to reduce the total cost of solar energy systems by about 75 percent before the end of the decade. The DOE estimated that a total installed cost of $$1 per watt for photovoltaic systems would be equivalent to 5-6¢/kilowatt hour (kWh) for energy available from the grid. The DOE also estimated that to meet the $1 per watt goal, PV module costs would need to be reduced to $ .50 per watt, balance of systems costs would need to be reduced to $.40 per watt, and power electronic costs would need to reach $.10 per watt. To address the BOS balance of systems cost component of the $1 per watt goal, the DOE announced a funding opportunity called (BOS-X) Extreme Balance of System Hardware Cost Reductions. The DOE identified eight areas within the total BOS costs: 1) installation labor, 2) installation materials, 3) installation overhead and profit, 4) tracker, 5) permitting and commissioning, 6) site preparation, 7) land acquisition, 8) sales tax. The BOS-X funding announcement requested applications in four specific topics;Topic 1: Transformational Building Integrated Photovoltaic (BIPV) Modules; Topic 2: Roof and Ground Mount Innovations; Topic 3: Transformational Photovoltaic System Designs; and Topic 4: Development of New Wind Load Codes for PV Systems.The application submitted by ARaymond Tinnerman reflected the requirements listed in Topic #2, Roof and Ground Mount Innovations. The goal of topic #2 was to develop technologies that would result in the extreme reduction of material and labor costs associated with applications that require physical connections and attachments to roof and ground mount structures. The topics researched in this project included component cost reduction, labor reduction, weight reduction, wiring innovations, and alternative material utilization. The project objectives included; 1) The development of an innovative quick snap bracket assembly that would be bonded to frameless PV modules for commercial rooftop installations; 2) The development of a composite pultruded rail to replace traditional racking materials; 3) In partnership with a roofing company, pilot the certification of a commercial roof to be solar panel compliant, eliminating the need for structural analysis and government oversight resulting in significantly decreased permitting costs; and 4) Reduce the sum of all cost impacts in topic #2 from a baseline total of $2.05/watt to $.34/watt.

  4. Spectral killers and Poisson bracket invariants

    OpenAIRE

    Seyfaddini, Sobhan

    2014-01-01

    We find optimal upper bounds for spectral invariants of a Hamiltonian whose support is contained in a union of mutually disjoint displaceable balls. This gives a partial answer to a question posed by Leonid Polterovich in connection with his recent work on Poisson bracket invariants of coverings.

  5. Hausdorff Distance evaluation of orthodontic accessories' streaking artifacts in 3D model superimposition

    Scientific Electronic Library Online (English)

    José, Rino Neto; Fernando Penteado Lopes da, Silva; Israel, Chilvarquer; João Batista de, Paiva; Angélica Maria, Hernandez.

    2012-10-01

    Full Text Available The aim of this study was to determine whether image artifacts caused by orthodontic metal accessories interfere with the accuracy of 3D CBCT model superimposition. A human dry skull was subjected three times to a CBCT scan: at first without orthodontic brackets (T1), then with stainless steel brack [...] ets bonded without (T2) and with orthodontic arch wires (T3) inserted into the brackets' slots. The registration of image surfaces and the superimposition of 3D models were performed. Within-subject surface distances between T1-T2, T1-T3 and T2-T3 were computed and calculated for comparison among the three data sets. The minimum and maximum Hausdorff Distance units (HDu) computed between the corresponding data points of the T1 and T2 CBCT 3D surface images were 0.000000 and 0.049280 HDu, respectively, and the mean distance was 0.002497 HDu. The minimum and maximum Hausdorff Distances between T1 and T3 were 0.000000 and 0.047440 HDu, respectively, with a mean distance of 0.002585 HDu. In the comparison between T2 and T3, the minimum, maximum and mean Hausdorff Distances were 0.000000, 0.025616 and 0.000347 HDu, respectively. In the current study, the image artifacts caused by metal orthodontic accessories did not compromise the accuracy of the 3D model superimposition. Color-coded maps of overlaid structures complemented the computed Hausdorff Distances and demonstrated a precise fusion between the data sets.

  6. Periodontally accelerated osteogenic orthodontics (PAOO) - a review

    OpenAIRE

    Amit, Goyal; JPS, Kalra; Pankaj, Bhatiya; Suchinder, Singla; Parul, Bansal

    2012-01-01

    With an increasing number of adult patients coming to the orthodontic clinic, the orthodontic professional is constantly looking for ways to accelerate tooth movement. Surgical intervention to affect the alveolar housing and tooth movement has been described in various forms for over a hundred years. However, it is the spirit of interdisciplinary collaboration in orthodontics has expanded the realm of traditional orthodontic tooth movement protocols. Periodontal accelerated osteogenic orthodo...

  7. Patients’ acceptance of corticotomy-assisted orthodontics

    OpenAIRE

    Zawawi KH

    2015-01-01

    Khalid H Zawawi Department of Orthodontics, Faculty of Dentistry, King Abdulaziz University, Jeddah, Saudi Arabia Objective: To study patients’ acceptance of corticotomy-assisted orthodontics as a treatment option.Methods: Adult patients seeking orthodontic treatment were asked to complete two sets of questionnaires; the first set included questions about age, sex, and level of education and general questions about orthodontic treatment; and the second set was related to the corticoto...

  8. Preparation and evaluation of orthodontic setup

    Directory of Open Access Journals (Sweden)

    Telma Martins de Araújo

    2012-06-01

    Full Text Available INTRODUCTION: An orthodontic or diagnostic setup consists in cutting and realigning the teeth in plaster models, making it an important resource in orthodontic treatment planning. OBJECTIVE: The aim of this article is to provide a detailed description of a technique to build an orthodontic setup model and a method to evaluate it. CONCLUSIONS: Although laborious, orthodontic setup procedure and analysis can provide important information such as the need for dental extractions, interproximal stripping, anchorage system, among others.

  9. Preparation and evaluation of orthodontic setup

    Scientific Electronic Library Online (English)

    Telma Martins de, Araújo; Lílian Martins, Fonseca; Luciana Duarte, Caldas; Roberto Amarante, Costa-Pinto.

    2012-06-01

    Full Text Available INTRODUCTION: An orthodontic or diagnostic setup consists in cutting and realigning the teeth in plaster models, making it an important resource in orthodontic treatment planning. OBJECTIVE: The aim of this article is to provide a detailed description of a technique to build an orthodontic setup mod [...] el and a method to evaluate it. CONCLUSIONS: Although laborious, orthodontic setup procedure and analysis can provide important information such as the need for dental extractions, interproximal stripping, anchorage system, among others.

  10. Raising the root. A look at orthodontic extrusion.

    Science.gov (United States)

    Oesterle, L J; Wood, L W

    1991-07-01

    A simple technique using bonded wires to establish anchorage and an attachment to a tooth requires a minimum of special materials or advanced skills in orthodontics. The bonded wire stabilizes the anchor unit and avoids any adverse tooth movement. PMID:1861008

  11. Surface topography, hardness, and frictional properties of GFRP for esthetic orthodontic wires.

    Science.gov (United States)

    Inami, Toshihiro; Tanimoto, Yasuhiro; Yamaguchi, Masaru; Shibata, Yo; Nishiyama, Norihiro; Kasai, Kazutaka

    2016-01-01

    In our previous study, glass-fiber-reinforced plastics (GFRPs) made from polycarbonate and glass fiber for esthetic orthodontic wires were prepared by using pultrusion. The purpose of the present study was to investigate the surface topography, hardness, and frictional properties of GFRPs. To investigate how fiber diameter affects surface properties, GFRP round wires with a diameter of 0.45 mm (0.018 in.) were prepared incorporating either 13 ?m (GFRP-13) or 7 ?m (GFRP-7) glass fibers. As controls, stainless steel (SS), cobalt-chromium-nickel alloy, ?-titanium (?-Ti) alloy, and nickel-titanium (Ni?Ti) alloy were also evaluated. Under scanning electron microscopy and scanning probe microscopy, the ?-Ti samples exhibited greater surface roughness than the other metallic wires and the GFRP wires. The dynamic hardness and elastic modulus of GFRP wires obtained by the dynamic micro-indentation method were much lower than those of metallic wires (p?brackets of GFRP-13 and GFRP-7 were 3.45?±?0.49 and 3.60?±?0.38 N, respectively; frictional forces against the ceramic brackets of GFRP-13 and GFRP-7 were 3.39?±?0.58 and 3.87?±?0.48 N, respectively. For both bracket types, frictional forces of GFRP wires and Ni?Ti wire were nearly half as low as those of SS, Co?Cr, and ?-Ti wires. In conclusion, there was no significant difference in surface properties between GFRP-13 and GFRP-7; presumably because both share the same polycarbonate matrix. We expect that GFRP wires will deliver superior sliding mechanics with low frictional resistance between the wire and bracket during orthodontic treatment. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 104B: 88-95, 2016. PMID:25631358

  12. The Eulerian buckling test for orthodontic wires.

    Science.gov (United States)

    De Santis, R; Dolci, F; Laino, A; Martina, R; Ambrosio, L; Nicolais, L

    2008-04-01

    Orthodontic treatment is mainly dependent on the loads developed by metal wires. The load developed by a buckled orthodontic wire is of great concern for molar distalization and cannot be simply derived from mechanical properties measured through classical tests (i.e. tensile, torsion, and bending). A novel testing method, based on the Eulerian approach of a simple supported beam, has been developed in order to measure the load due to buckling of orthodontic wires. Elastic titanium molybdenum alloy (TMA; SDS Ormco) and superelastic Nitinol (3M Unitek) and copper nickel-titanium (NiTi; SDS Ormco) wires, each having a rectangular cross section of 0.016 x 0.022 square inches (0.41 x 0.56 mm(2)), were used. The wires were activated and deactivated by loading and unloading. In order to analyse thermo-mechanical properties in buckling, mechanical tests were assisted by calorimetric measurements through differential scanning calorimetry (DSC). Statistical analysis to determine differences between the samples was undertaken using two-way analysis of variance (ANOVA) and Tukey's post hoc test, and one-way ANOVA to assess differences between the tested wires under similar conditions and different materials. The results suggest that the load due to buckling depends on material composition, wire length, the amount of activation, temperature, and deformation rate. The results can be considered as the lower bound for the loads experienced by teeth as far as a buckled wire is concerned. At a temperature higher than the austenite finish transition temperature, superelastic wires were strongly dependent on temperature and deformation rate. The effect due to an increase of deformation rate was similar to that of a decrease of temperature. Load variations due to temperature of a superelastic wire with a length of 20 mm were estimated to be approximately 4 g/degrees C. The high performance of an applied superelastic wire may be related to the high dynamics of the load in relation to temperature. PMID:18263890

  13. Corticotomy-assisted orthodontic treatment

    Science.gov (United States)

    Hassan, Ali H.; Al-Saeed, Samar H.; Al-Maghlouth, Basma A.; Bahammam, Maha A.; Linjawi, Amal I.; El-Bialy, Tarek H.

    2015-01-01

    Objectives: To systematically review the literature to assess the quality of evidence related to corticotomy-assisted orthodontic treatment (CAOT) as adjunctive treatment in orthodontics. Methods: The study was conducted in the Faculty of Dentistry, King Abdulaziz University, Jeddah, Saudi Arabia between 2013 and 2014. Various electronic databases were searched and abstracts were retrieved. Defined inclusion criteria were then applied to the obtained original articles for further evaluation by 2 examiners independently. The criteria of selection included human, or animal studies, which assessed some aspects of CAOT and/or the biological principles behind it. Case reports and series were excluded. The quality of the studies was evaluated by the methodological score for clinical trials developed. Results: Fourteen articles were retrieved initially, but only 12 articles were finally selected for the study. The CAOT was found to accelerate tooth movement by 2-2.5 folds when compared with conventional orthodontic tooth movement. The CAOT was found safe on periodontal health and exhibits no or little risk of root resorption. A localized turnover of alveolar spongiosa and the absence of a hyalinized zone was the acceptable biological explanation of CAOT. There is no evidence to support that CAOT enhances the movement of ankylosed teeth, closing old extraction sites, post-orthodontic stability, or transverse expansion. Conclusions: Corticotomy-assisted orthodontic treatment should be considered with caution. Long term randomized clinical trials are still needed. PMID:26108582

  14. Corrosion of weldments in orthodontic appliances

    International Nuclear Information System (INIS)

    The study of corrosion-related problems of dental materials has undergone a considerable development in recent years in order to avoid the use of materials with insufficient corrosion resistance in patients mouth. The subject of the present work was to study a particular type of corrosion: galvanic corrosion. One of the most common case of galvanic couples in patients mouth are the orthodontic appliances. The materials studied in the present work were stainless steel strips and silver-copper wires, isolated and welded between them. The electrochemical tests were performed in a NaCl 0.1M and Lactic Acid 0.1 M solution (pH2.3), and after test, the specimens were observed using the optical and scanning electron microscope. The results show that when stainless steel is coupled with a silver solder, the last is the anode of the galvanic couple. As a consequence of this, the silver solder undergone a severe attack. Stainless steel orthodontic appliances with silver solder are feasibly destroyed due to a severe attack on the filler metal disjoining the welded parts. (author) 9 refs

  15. The correlation between pain perception among patients with six different orthodontic archwires and the degree of dental crowding

    Directory of Open Access Journals (Sweden)

    Markovi? Evgenija

    2015-01-01

    Full Text Available Introduction. Forces generated in orthodontic treatment with fixed appliances create tension and compression zones in the periodontal ligament resulting in a painful experience for patients. In the first phase of orthodontic treatment, when leveling of teeth is needed, nickel-titanium (NiTi archwires can be completely engaged in brackets, even in the cases of extreme crowding, exerting small forces. There is a great individual variation in the pain perception related to the application of orthodontic forces. Objective. The aim of this study was to investigate the pain perception among patients with dental crowding after insertion of six different NiTi orthodontic archwires as a part of fixed appliances in the first stage of orthodontic treatment. Methods. The study was conducted on a sample of 189 orthodontic patients receiving one of six different either superelastic or heat activated NiTi archwires, in the first phase of orthodontic treatment. Pain perception was evaluated in groups of patients with different degree of crowding. The modified McGill Pain Questionnaire with Visual Analogue Scale was used to evaluate the quality and intensity of pain. Statistical analysis was performed using simple descriptive statistics, and Pearson`s chi-square test with statistical significance of p<0.05. Results. Majority of patients reported pain as discomfort or pressure of moderate intensity caused by chewing or biting, started within 12 hours, carried on for 3-4 days, and decreased over time without self-medication. Conclusion. No correlation was found between pain perception among patients with different types of NiTi archwires and the degree of crowding.

  16. Orthodontic bonded retainers.

    Science.gov (United States)

    Butler, Jonathan; Dowling, Paul

    2005-01-01

    Retention is usually necessary following orthodontic treatment to overcome the elastic recoil of the periodontal supporting fibres and to allow remodelling of the alveolar bone. The degree of change is variable and largely unpredictable. Bonded lingual retainers have been shown to be an effective means of retaining aligned anterior teeth in the post-treatment position in the long term. Two basic designs of lingual bonded retainers are currently in use. Rigid mandibular canine-to-canine retainers are attached to the canines only. They are effective in maintaining intercanine width but less so in preventing individual tooth rotations. Flexible spiral wire retainers are bonded to each tooth in the segment, their flexibility allowing for physiological movement of the teeth. This design is more effective at preventing rotation of the bonded teeth. Failure of bonded retainers may occur at the wire-composite interface, at the adhesive-enamel interface or as a stress fracture of the wire. Failure of a retainer may lead to unwanted tooth movement. In many cases it will be possible to repair the appliance in the mouth. However, in some instances it will be necessary to replace the retainer. A disadvantage of fixed retainers is that they complicate oral hygiene procedures, and favour the accumulation of plaque and calculus. Despite this, the presence of a bonded retainer appears to cause no increase in incidence of caries or periodontal disease. Use of interdental cleaning aids is required to ensure adequate oral hygiene. PMID:15789987

  17. Asymmetric extractions in orthodontics

    Scientific Electronic Library Online (English)

    Camilo Aquino, Melgaço; Mônica Tirre de Souza, Araújo.

    2012-04-01

    Full Text Available INTRODUCTION: Extraction decisions are extremely important in during treatment planning. In addition to the extraction decision orthodontists have to choose what tooth should be extracted for the best solution of the problem and the esthetic/functional benefit of the patient. OBJECTIVE: This article [...] aims at reviewing the literature relating the advantages, disadvantages and clinical implications of asymmetric extractions to orthodontics. METHODS: Keywords were selected in English and Portuguese and the EndNote 9 program was used for data base search in PubMed, Web of Science (WSc) and LILACS. The selected articles were case reports, original articles and prospective or retrospective case-control studies concerning asymmetrical extractions of permanent teeth for the treatment of malocclusions. CONCLUSION: According to the literature reviewed asymmetric extractions can make some specific treatment mechanics easier. Cases finished with first permanent molars in Class II or III relationship in one or both sides seem not to cause esthetic or functional problems. However, diagnosis knowledge and mechanics control are essential for treatment success.

  18. Speedy orthodontics: a case report.

    Science.gov (United States)

    Krishnan, K V; Kumaran, N Kurunji; Rajasigamani, K; Vijay, V; Rajaram, R S; Bhaskar, V

    2013-01-01

    Management of severe rotation poses a great challenge for the orthodontist, especially when cortical anchorage occurs. The conventional methods require excessive treatment time, rely on patient compliance, and can cause root resorption. A groundbreaking new procedure developed by Wilcko et al, which is actually a modification of the conventional corticotomy procedure, amalgamates the orthodontic mechanics, alveolar decortications, and augmentation procedure to make treatment time three to four times faster than conventional orthodontic techniques. This procedure uses the dynamics of bone physiology and redirects the emphasis in tooth movement to the manner in which supporting bone responds to orthodontic forces applied to the tooth. This article includes a case report in which the technique is used on a patient who has a severely rotated mandibular left canine. PMID:23646344

  19. Metal Hypersensitivity in Orthodontic Patients

    Directory of Open Access Journals (Sweden)

    Sandhya Maheshwari Sanjeev K

    2015-06-01

    Full Text Available Orthodontic treatment of individuals with metal hypersensitivity is a matter of concern for the orthodontist. Orthodontic appliances contain metals like Nickel, Cobalt and Chromium etc. Metals may cause allergic reactions and are known as allergens. Reaction to these metals is due to biodegradation of metals in the oral cavity. This may lead to the formation of corrosion products and their exposure to the patient. Nickel is the most common metal to cause hypersensitivity reaction. Chromium ranks second among the metals, known to trigger allergic reactions. The adverse biological reactions to these metals may include hypersensitivity, dermatitis and asthma. In addition, a significant carcinogenic and mutagenic potential has been demonstrated. The orthodontist must be familiar with the best possible alternative treatment modalities to provide the safest, most effective care possible in these cases. The present article focuses on the issue of metal hypersensitivity and its management in orthodontic

  20. Periodontal status of Pakistani orthodontic patients

    Directory of Open Access Journals (Sweden)

    Yousuf MOOSA

    2015-01-01

    Full Text Available The objective of this study was to evaluate and compare the periodontal status of orthodontic patients and non-orthodontic patients, aged 15–28 years, of both genders. The cross-sectional study included 100 orthodontic and 100 non-orthodontic patients evaluated using a Community Periodontal Index for Treatment Need (CPITN probe on the index teeth. A questionnaire was distributed to the participants to assess and evaluate the use of oral hygiene aids. The data were analyzed using SPSS version 17, and various comparisons were performed using the chi-square test. The study revealed that there was a statistically significant association in CPITN scores between the orthodontic and non-orthodontic patients (p < 0.01. The study showed that patients undergoing orthodontic treatment have increased plaque accumulation and probing depth resulting in periodontal tissue destruction. Proper oral hygiene practices and interdental aids should be employed to control plaque.

  1. Hydrodynamic Nambu Brackets derived by Geometric Constraints

    CERN Document Server

    Blender, Richard

    2015-01-01

    A geometric approach to derive the Nambu brackets for ideal two-dimensional (2D) hydrodynamics is suggested. The derivation is based on two-forms with vanishing integrals in a periodic domain, and with resulting dynamics constrained by an orthogonality condition. As a result, 2D hydrodynamics with vorticity as dynamic variable emerges as a generic model, with conservation laws which can be interpreted as enstrophy and energy functionals. Generalized forms like surface quasi-geostrophy and fractional Poisson equations for the stream-function are also included as results from the derivation. The formalism is extended to a hydrodynamic system coupled to a second degree of freedom, with the Rayleigh-B\\'{e}nard convection as an example. This system is reformulated in terms of constitutive conservation laws with two additive brackets which represent individual processes: a first representing inviscid 2D hydrodynamics, and a second representing the coupling between hydrodynamics and thermodynamics. The results can b...

  2. Lie Bracket Approximation of Extremum Seeking Systems

    OpenAIRE

    Dürr, Hans-Bernd; Stankovi?, Miloš S.; Ebenbauer, Christian; Johansson, Karl H.

    2011-01-01

    Extremum seeking feedback is a powerful method to steer a dynamical system to an extremum of a partially or completely unknown map. It often requires advanced system-theoretic tools to understand the qualitative behavior of extremum seeking systems. In this paper, a novel interpretation of extremum seeking is introduced. We show that the trajectories of an extremum seeking system can be approximated by the trajectories of a system which involves certain Lie brackets of the v...

  3. Conceptual design for PSP mounting bracket

    Energy Technology Data Exchange (ETDEWEB)

    Ransom, G.; Stein, R. [Martin Marietta Energy Systems, Inc., Piketon, OH (United States)

    1991-12-31

    Protective structural packages (PSP`s or overpacks) used to ship 2 1/2-ton UF{sub 6} product cylinders are bolted to truck trailers. All bolts penetrate two longitudinal rows of wooden planks. Removal and replacement is required at various intervals for maintenance and routine testing. A conceptual design is presented for mounting brackets which would securely attach PSP`s to trailer frames, reduce removal and replacement time, and minimize risk of personnel injury.

  4. Effect of fixed orthodontic appliances on salivary microbial parameters at 6 months: a controlled observational study

    Scientific Electronic Library Online (English)

    Delphine, MARET; Christine, MARCHAL-SIXOU; Jean-Noel, VERGNES; Olivier, HAMEL; Marie, GEORGELIN-GURGEL; Lucas, VAN DER SLUIS; Michel, SIXOU.

    2014-01-01

    Full Text Available Objective: The aim of this study was to assess the microbial changes in children with fixed orthodontic appliances compared with a control group of children without orthodontic treatment. Material and Methods: Ninety-five children, aged between 12 and 16 years, participated in this study. Fort [...] y-eight subjects were fitted with fixed orthodontic appliances and forty-seven were free of any such appliances. The follow-up was 6 months for all children. The association between orthodontic appliances and high levels of Streptococcus mutans and Lactobacillus spp was assessed with logistic regression models, taking age, sex, pH and buffer capacity into account. Results: Differences at baseline between the two groups were not statistically significant. We found that wearing a fixed orthodontic appliance was associated with high levels of Streptococcus mutans and Lactobacillus spp (adjusted OR: 6.65, 95% CI [1.98-22.37]; 9.49, 95% CI [2.57-35.07], respectively), independently of other variables. Conclusion: The originality of the present epidemiological study was to evaluate the evolution of salivary microbial parameters in a population of children with fixed orthodontic appliances. Our results show an increase of Streptococcus mutans and Lactobacillus spp values during the follow-up. The whole dental workforce should be aware that preventive measures are of paramount importance during orthodontic treatment.

  5. Genotoxic evaluation of orthodontic bonding adhesives exposed to electron beam irradiation: an in vitro study

    International Nuclear Information System (INIS)

    To evaluate the in vitro genotoxicity of two orthodontic adhesives and to determine the type of cell death they induce on human lymphocytes after exposing to Electron Beam Irradiation. The materials tested were 1. Light cure orthodontic adhesive with conventional primer (Transbond XT3M) and 2. Self cure orthodontic adhesive (Unite, 3M). Cured sterile individual masses were immersed in Phosphate Buffer saline and left at 370℃ for 24 h. Then a volume of 200 μL of the extract medium was mixed with human peripheral blood lymphocyte tested for comet assay by single cell DNA damage assay and apoptosis by DNA diffusion agar assay. The results showed all parameters studied by comet assay were significant (P>0.05). In case of apoptosis, light cure orthodontic adhesive (188.92±55.05) and self cure orthodontic adhesives (255.23±76.43) showed increased diffusion of DNA compared to normal lymphocyte (111.22±8.78). However the level of DNA diffusion was not significantly different between the two adhesives. Light cure orthodontic and self cure orthodontic adhesives were induced apoptosis. Both the adhesives had no significant effect on the percentage of DNA tail and olive tail moment. (author)

  6. Autoclaving and clinical recycling: Effects on mechanical properties of orthodontic wires

    OpenAIRE

    Oshagh, M.; M R Hematiyan; Y Mohandes; M R Oshagh; L Pishbin

    2012-01-01

    Background: About half of the orthodontists recycle and reuse orthodontic wires because of their costs. So when talking about reuse and sterilization of wires, their effects on mechanical properties of wires should be clarified. The purpose of this study was to assess the effects of sterilization and clinical use on mechanical properties of stainless steel wires. Materials and Methods: Thirty stainless steel orthodontic wires were divided into three equal groups of control, autoclave (ster...

  7. Which Factors Affect Dental Esthetics and Smile Attractiveness in Orthodontically Treated Patients?

    OpenAIRE

    Farzaneh Ahrari; Farzin Heravi; Roozbeh Rashed; Mohammad Javad Zarrabi; Yasin Setayesh

    2016-01-01

    Objectives: This study aimed to find the factors that affect dental esthetics and smile attractiveness in orthodontically treated patients according to laypeople’s judgment, and to determine whether there is any relationship between dental and smile esthetics.Materials and Methods: Using the Q-sort technique, 60 laypersons (30 males, 30 females) rated dental and smile photographs of 48 orthodontically treated patients based on their degree of attractiveness. Dental and smile parameters of eac...

  8. The effect of various oral hygiene products on the microbial flora in patients undergoing orthodontic treatment

    OpenAIRE

    Preeti Chauhan; Vinay S Dua; Nitika Kainth; Ashu Tosh; Anshul Tomar

    2015-01-01

    Context: Orthodontic devices lead to significantly greater plaque accumulation and gingival inflammation resulting in a change of gingival flora from cocci and rods to motile organisms like spirochetes. Aims: The aim was to study the effect of various oral hygiene products on the microbial flora in patients undergoing orthodontic treatment. Materials and Methods: The microbial composition of 40 patients, divided into four groups of 10 patients each, was evaluated. Group I patients were prescr...

  9. Effect of intrusive and retraction forces in labial and lingual orthodontics: A finite element study

    OpenAIRE

    Rohan Mascarenhas; Ameet V Revankar; Jenny Mary Mathew; Laxmikanth Chatra; Akhter Husain; Satish Shenoy

    2014-01-01

    Objectives: Lingual orthodontics differs in biomechanics as compared to labial system and has biomechanical advantages. Although theoretical approaches have explained the differences between labial and lingual orthodontics, the finite element method (FEM) may be better suited to analyze these differences. This study analyzes the effect of vertical and horizontal forces together on the tooth using FEM. Materials and Methods: An extracted right maxillary central incisor was radiographed and was...

  10. A clinical and radiographic study to evaluate the rate of retraction of maxillary canine using nickel-titanium closed coil spring with two different bracket systems

    Directory of Open Access Journals (Sweden)

    P Adarsh Reddy

    2014-01-01

    Full Text Available Objectives: This study compares the efficiency of self-ligating brackets with the conventional preadjusted edgewise (PEA brackets during maxillary canine retraction using nickel-titanium closed coil springs. Materials and Methods: The sample comprised of 20 healthy patients (10 males and 10 females, within age groups 16-26 years (mean, 20 years having Class I malocclusion with bimaxillary protrusion. All patients underwent bilateral extraction of the maxillary first bicuspids and retraction of the maxillary canines with fixed self-ligating brackets (3M Smart clip and PEA appliance (3M Gemini. The initial records included standard intra- and extra-oral photographs, study models, lateral cephalograms, and panoramic radiographs. Results: The mean distal movement of canines in self-ligating brackets was 0.89 mm/mo with standard deviation of 0.255 and in preadjusted edgewise brackets, the mean distal movement of canines was 0.87 mm/mo with standard deviation of 0.214. The mean tipping of canine in self-ligating brackets was 7.45 ± 1.050(0 and in PEA brackets it was 7.70° ± 1.21°. The mean rotation of canine in self-ligating brackets was 7.65° ± 3.47° and in preadjusted edgewise appliance it was 12.30° ± 3.08°. Conclusion: The rates of distal movement of the maxillary canines were similar with both conventional and self-ligating brackets. Rotation of the maxillary canines during retraction was minimized with self-ligating brackets in comparison to conventional bracket systems.

  11. A comparative evaluation of the effectiveness of erbium-doped yttrium aluminum garnet laser with other in house refurbishing methods for reconditioning stainless steel and ceramic brackets. An environmental scanning electron microscope and shear bond strength analysis: An in-vitro study

    OpenAIRE

    Nimay Devjee; Sonali V Deshmukh; Sandeep Jethe; Charudatta R Naik

    2015-01-01

    Introduction: Brackets can be recycled by sending them to a commercial recycling company but it is time consuming and the bracket cannot be bonded in the same appointment. Hence in-house methods for recycling of brackets would be beneficial to both the orthodontist and the patient. Aim: In our study, we compared the shear bond strength of brackets after being recycled with erbium-doped yttrium aluminum garnet (ER:YAG) laser, sandblasting and the thermal method. Materials and Methods: The stud...

  12. Body dysmorphic disorder in Iranian orthodontic patients.

    Science.gov (United States)

    Yassaei, Soghra; Goldani Moghadam, Mahdjoube; Aghili, Hossein; Tabatabaei, Seyed Mahmoud

    2014-01-01

    Patient's preoccupations with perceived defect in appearance or excessive concern about minimal flaws are among diagnostic criteria of body dysmorphic disorder (BDD). Sufferers usually seek cosmetic procedures such as orthodontic treatment. This study was conducted to estimate the prevalence of BDD among a sample of Iranian orthodontic patients. A total of 270 orthodontic patients were evaluated with BDD-YBOCS questionnaire for the diagnosis of BDD. Fifteen patients (5.5%) were screened positive for BDD. BDD was more frequent among females, singles and in younger patients. Most of the BDD patients experienced multiple previous orthodontic evaluations. The relative high prevalence of BDD among orthodontic patients in Iran offers that orthodontists should take psychologically based problems such as BDD into account while evaluating patient's orthodontic problems. PMID:25130153

  13. Body dysmorphic disorder in Iranian orthodontic patients.

    Directory of Open Access Journals (Sweden)

    Soghra Yassaei

    2014-06-01

    Full Text Available Patient's preoccupations with perceived defect in appearance or excessive concern about minimal flaws are among diagnostic criteria of body dysmorphic disorder (BDD. Sufferers usually seek cosmetic procedures such as orthodontic treatment. This study was conducted to estimate the prevalence of BDD among a sample of Iranian orthodontic patients. A total of 270 orthodontic patients were evaluated with BDD-YBOCS questionnaire for the diagnosis of BDD. Fifteen patients (5.5% were screened positive for BDD. BDD was more frequent among females, singles and in younger patients. Most of the BDD patients experienced multiple previous orthodontic evaluations. The relative high prevalence of BDD among orthodontic patients in Iran offers that orthodontists should take psychologically based problems such as BDD into account while evaluating patient's orthodontic problems.

  14. Periodontal status of Pakistani orthodontic patients

    Scientific Electronic Library Online (English)

    Yousuf, MOOSA; Ling Na, HAN; Jawad, SAFDAR; Omair Ahmed, SHEIKH; Ya Ping, PAN.

    Full Text Available The objective of this study was to evaluate and compare the periodontal status of orthodontic patients and non-orthodontic patients, aged 15–28 years, of both genders. The cross-sectional study included 100 orthodontic and 100 non-orthodontic patients evaluated using a Community Periodontal Index fo [...] r Treatment Need (CPITN) probe on the index teeth. A questionnaire was distributed to the participants to assess and evaluate the use of oral hygiene aids. The data were analyzed using SPSS version 17, and various comparisons were performed using the chi-square test. The study revealed that there was a statistically significant association in CPITN scores between the orthodontic and non-orthodontic patients (p

  15. Peierls brackets in non-Lagrangian field theory

    CERN Document Server

    Sharapov, Alexey

    2014-01-01

    The concept of Lagrange structure allows one to systematically quantize the Lagrangian and non-Lagrangian dynamics within the path-integral approach. In this paper, I show that any Lagrange structure gives rise to a covariant Poisson brackets on the space of solutions to the classical equations of motion, be they Lagrangian or not. The brackets generalize the well-known Peierls' bracket construction and make a bridge between the path-integral and the deformation quantization of non-Lagrangian dynamics.

  16. Effect of pre-strain on microstructure of Ni-Ti orthodontic archwires

    Energy Technology Data Exchange (ETDEWEB)

    Jafari, J. [Department of Materials Science and Engineering, Engineering Faculty, Ferdowsi University of Mashhad, Azadi Square, P.O. Box 91775-1111, Mashhad (Iran, Islamic Republic of); Zebarjad, S.M. [Department of Materials Science and Engineering, Engineering Faculty, Ferdowsi University of Mashhad, Azadi Square, P.O. Box 91775-1111, Mashhad (Iran, Islamic Republic of)], E-mail: Zebarjad@um.ac.ir; Sajjadi, S.A. [Department of Materials Science and Engineering, Engineering Faculty, Ferdowsi University of Mashhad, Azadi Square, P.O. Box 91775-1111, Mashhad (Iran, Islamic Republic of)

    2008-01-25

    One of the most important applications of shape memory alloy is in medicine, especially orthodontic archwires. In this category Ni-Ti orthodontic archwires is one of the oldest used materials. Biocompatibility, corrosion resistance, super elasticity, etc. are its outstanding properties. In spite of the importance of dependency of pre-strain on microstructure of Ni-Ti there are limited sources concentrated on the subject. For this reason the main purpose of the current study is determination of the effect of pre-strain on microstructure of Ni-Ti orthodontic archwires. In this regard, three-point bending was performed on the orthodontic archwire specimens to apply different amount of strain. The microstructures were compared with the un-strained wire using optical and scanning electron microscopes. The results showed that the stable phase depends strongly on the value of pre-strain. Increasing pre-strain causes to decrease martensite laths and leads the microstructure toward austenite phase.

  17. Corticotomy-Assisted Orthodontic Treatment: Review

    OpenAIRE

    Hassan, Ali H; Al-Fraidi, Ahmad A; Al-Saeed, Samar H

    2010-01-01

    Corticotomy-assisted orthodontic treatment is an established and efficient orthodontic technique that has recently been studied in a number of publications. It has gradually gained popularity as an adjunct treatment option for the orthodontic treatment of adults. It involves selective alveolar decortication in the form of decortication lines and dots performed around the teeth that are to be moved. It is done to induce a state of increased tissue turnover and a transient osteopenia, whi...

  18. Body dysmorphic disorder in Iranian orthodontic patients.

    OpenAIRE

    Soghra Yassaei; Mahdjoube Goldani Moghadam; Hossein Aghili; Seyed Mahmoud Tabatabaei

    2014-01-01

    Patient's preoccupations with perceived defect in appearance or excessive concern about minimal flaws are among diagnostic criteria of body dysmorphic disorder (BDD). Sufferers usually seek cosmetic procedures such as orthodontic treatment. This study was conducted to estimate the prevalence of BDD among a sample of Iranian orthodontic patients. A total of 270 orthodontic patients were evaluated with BDD-YBOCS questionnaire for the diagnosis of BDD. Fifteen patients (5.5%) were screened posit...

  19. The Poisson bracket on free null initial data for gravity.

    Science.gov (United States)

    Reisenberger, Michael P

    2008-11-21

    Free initial data for general relativity on a pair of intersecting null hypersurfaces are well known, but the lack of Poisson brackets and concerns about caustics have stymied the development of a constraint free canonical theory. Here it is pointed out how caustics and generator crossings can be neatly avoided and Poisson brackets on free data are given. On sufficiently regular functions of the solution spacetime geometry these brackets match the Poisson brackets defined on such functions by the Hilbert action via Peierls' prescription. The symplectic 2-form is also given in terms of free data. PMID:19113400

  20. Experimental study of some mounting brackets to support fuel elements

    International Nuclear Information System (INIS)

    In an atomic pile with vertical channels, fuel elements are stacked on one another. According to a possible assembly, fuel element can be contained by a graphite sleeve and be supported by a mounting bracket in this sleeve. Sleeves are then stacked on one another. The authors report the investigation of different designs for these mounting brackets. They describe their mechanical role and their mechanical, aerodynamic, neutronic and test conditions. They report tests performed on brackets made in graphite and on brackets made in stainless steel and graphite, and discuss the obtained results

  1. Corrosion behaviour of metallic biomaterials used as orthodontic wires

    Directory of Open Access Journals (Sweden)

    A. Zi?bowicz

    2008-04-01

    Full Text Available Purpose: The aim of the work was evaluation of the corrosion resistance of the commercial metallic orthodontic wires from different manufacturers in simulated intra-oral environment.Design/methodology/approach: Corrosion resistance tests were carried out in artificial saliva at the temperature 37±1°C with the use of the VoltaLab® PGP 201 system for electrochemical tests. The saturated calomel electrode (SCE was applied as the reference electrode and the auxiliary electrode was a platinum foil. The evaluation of pitting corrosion was realized by recording of anodic polarization curves with the use of the potentiodynamic method. In order to evaluate crevice corrosion resistance the samples were polarized in the potential equalto 0.8 V by 900 seconds.Findings: Results of corrosion resistance tests of the CrNi, NiTi and CuNiTi wires showed comparable data of parameters obtained in the artificial saliva.Research limitations/implications: The obtained results show the influence of artificial saliva on the electrochemical corrosion of orthodontic wires. In order to demonstrate the higher risk of corrosion, which can have two consequences: a loss of the physical properties and the release of Ni ions (which have been shown to be toxic and the cause of allergic reactions - additional research on fatigue corrosion should be carried out.Originality/value: The analysis of the obtained results show that that commonly used materials for making orthodontic wires (because of their interesting properties - elasticity and shape memory can be used in different orthodontic treatment stages to correct numerous clinical conditions. The most favorable characteristics were observed for the new NiTi samples (American Orthodontics.

  2. From Peierls brackets to a generalized Moyal bracket for type-I gauge theories

    CERN Document Server

    Esposito, G; Esposito, Giampiero; Stornaiolo, Cosimo

    2006-01-01

    In the space-of-histories approach to gauge fields and their quantization, the Maxwell, Yang--Mills and gravitational field are well known to share the property of being type-I theories, i.e. Lie brackets of the vector fields which leave the action functional invariant are linear combinations of such vector fields, with coefficients of linear combination given by structure constants. The corresponding gauge-field operator in the functional integral for the in-out amplitude is an invertible second-order differential operator. For such an operator, we consider advanced and retarded Green functions giving rise to a Peierls bracket among group-invariant functionals. Our Peierls bracket is a Poisson bracket on the space of all group-invariant functionals in two cases only: either the gauge-fixing is arbitrary but the gauge fields lie on the dynamical sub-space; or the gauge-fixing is a linear functional of gauge fields, which are generic points of the space of histories. In both cases, the resulting Peierls bracke...

  3. Assessment of surface friction of self-ligating brackets under conditions of angulated traction / Avaliação da fricção superficial apresentada por braquetes autoligáveis em condições de tracionamento sob angulação

    Scientific Electronic Library Online (English)

    Roberta, Buzzoni; Carlos N., Elias; Daniel J., Fernandes; José Augusto M., Miguel.

    2012-08-01

    Full Text Available OBJETIVO: avaliar a fricção apresentada por braquetes autoligáveis de aço inoxidável com sistema passivo de tampa deslizante sob angulação de 0 grau e 2,5 graus, e comparar o comportamento desse grupo sob angulação nula com o de um grupo de braquetes autoligáveis com sistema ativo de tampa resilient [...] e. MÉTODOS: foram utilizados 25 braquetes de caninos superiores, divididos em 5 grupos - braquetes autoligáveis passivos Damon SL II sob angulação de 0 grau e de 2,5 graus; braquetes convencionais Gemini amarrados com ligaduras elásticas sob as mesmas angulações; e um grupo formado pelo sistema ativo Time 2, sob angulação nula. A hipótese a ser testada é se artefatos autoligáveis com sistema de tampa passiva são mais efetivos no controle da fricção do que dispositivos contendo coberturas ativas. O tracionamento foi realizado segundo emprego de 25 segmentos de fio de aço inoxidável 0,020" na máquina de ensaios EMIC DL 10000 com célula de carga de 2,0kg. Cada conjunto braquete/fio foi responsável pela geração de quatro corpos de prova, totalizando-se 100 leituras. As comparações entre médias dos valores foram realizadas através da Análise de Variância (one-way ANOVA) com correções pelo coeficiente de Bonferroni. RESULTADOS E CONCLUSÃO: as médias de fricção encontradas confirmaram a hipótese em teste, de que o sistema de braquetes Damon SL II é mais eficiente no controle do atrito do que o sistema de tampa ativa sob angulação de 0 grau (p Abstract in english OBJECTIVE: The aim of this study was to assess resistance to sliding of stainless steel passive self-ligating brackets with 0° and 2.5° angulations and to compare them to active self-ligating brackets at zero angulation. The hypothesis to be tested was that passive self-ligating brackets produce low [...] er frictional forces than active self-ligating brackets. METHODS: Twenty five 0.022 x 0.028-in slot maxillary canine brackets were divided into 5 groups of 5 brackets: Damon SL II (Ormco, CA, USA) self-ligating bracket and Gemini (3M/Unitek, CA, USA) conventional bracket with angulation of 0 and 2.5° and a group of Speed 2 (American Orthodontics, WI, USA) active clip self-ligating system with zero angulation. Twenty five segments of stainless steel 0.020-in archwire (TP Orthodontics, IN, USA) were tested and each bracket/wire interface was evaluated at 4 successive points during sliding. Overall, 100 frictional values were analyzed by parametric analysis of variance and Bonferroni tests. RESULTS AND CONCLUSION: Frictional tests were performed with an Emic DL 10000 testing machine (Emic, Brazil) with a load cell of one kilogram. Passive self-ligating brackets produced lower frictional forces than active self-ligating brackets (p

  4. REVIEW ON PERIODONTALLY ASSISTED ORTHODONTICS TREATMENT

    Directory of Open Access Journals (Sweden)

    Ayesha

    2014-05-01

    Full Text Available It is well known that most of the orthodontic treatments require more time for completion of the treatment. This technique literally accelerates the orthodontic corrections. Periodontally - assisted orthodontic treatment is an established and efficient orthodontic technique that has recently been studied in a number of publications. It has gradually gained popularity as an adjunct treatment option for the orthodontic treatment of adults. It involves selective alveolar decortication in the form of decortication lines and dots performed around the teeth that are to be moved. It is done to induce a state of increased tissue turnover and a transient osteopenia, which is followed by a faster rate of orthodontic tooth movement. Orthodontic treatment time with this technique will be reduced to one-third the time of conventional orthodontics. This technique has several advantages, including faster tooth movement, shorter treatment time, and safer expansion of constricted arches, enhanced post-orthodontic treatment stability and extended envelope of tooth movement. The aim of this article is to present a comprehensive review of the literature, including historical background, contemporary clinical techniques, indications, contraindications, complications and side effects.

  5. Hydrodynamic Nambu brackets derived by geometric constraints

    International Nuclear Information System (INIS)

    A geometric approach to derive the Nambu brackets for ideal two-dimensional (2D) hydrodynamics is suggested. The derivation is based on two-forms with vanishing integrals in a periodic domain, and with resulting dynamics constrained by an orthogonality condition. As a result, 2D hydrodynamics with vorticity as dynamic variable emerges as a generic model, with conservation laws which can be interpreted as enstrophy and energy functionals. Generalized forms like surface quasi-geostrophy and fractional Poisson equations for the stream-function are also included as results from the derivation. The formalism is extended to a hydrodynamic system coupled to a second degree of freedom, with the Rayleigh–Bénard convection as an example. This system is reformulated in terms of constitutive conservation laws with two additive brackets which represent individual processes: a first representing inviscid 2D hydrodynamics, and a second representing the coupling between hydrodynamics and thermodynamics. The results can be used for the formulation of conservative numerical algorithms that can be employed, for example, for the study of fronts and singularities. (paper)

  6. NSAIDs in orthodontic tooth movement

    OpenAIRE

    Karthi, Muthukumar; Anbuslevan, Gobichettipalyam Jagtheeswaran; Senthilkumar, Kullampalyam Palanisamy; Tamizharsi, Senthilkumar; Raja, Subramani; Prabhakar, Krishnan

    2012-01-01

    Orthodontic tooth movement is basically a biological response toward a mechanical force. The movement is induced by prolonged application of controlled mechanical forces, which create pressure and tension zones in the periodontal ligament and alveolar bone, causing remodeling of tooth sockets. Orthodontists often prescribe drugs to manage pain from force application to biologic tissues. Nonsteroidal anti-inflammatory drugs (NSAIDs) are the drugs usually prescribed. NSAIDs block prostaglandin ...

  7. Microbiologically influenced corrosion of orthodontic metallic appliances.

    Science.gov (United States)

    Kameda, Takashi; Oda, Hirotake; Ohkuma, Kazuo; Sano, Natsuki; Batbayar, Nomintsetseg; Terashima, Yukari; Sato, Soh; Terada, Kazuto

    2014-01-01

    Biocorrosion (microbiologically influenced corrosion; MIC) occur in aquatic habitats varying in nutrient content, temperature, stress and pH. The oral environment of organisms, including humans, should be one of the most hospitable for MIC. Corrosion of metallic appliances in the oral region is one cause of metal allergy in patients. In this study, an inductively coupled plasma-optical emission spectrometer revealed elution of Fe, Cr and Ni from stainless steel (SUS) appliances incubated with oral bacteria. Three-dimensional laser confocal microscopy also revealed that oral bacterial culture promoted increased surface roughness and corrosion pits in SUS appliances. The pH of the supernatant was lowered after co-culture of appliances and oral bacteria in any combinations, but not reached at the level of depassivation pH of their metallic materials. This study showed that Streptococcus mutans and Streptococcus sanguinis which easily created biofilm on the surfaces of teeth and appliances, did corrode orthodontic SUS appliances. PMID:24583645

  8. In vitro corrosion behavior of lingual orthodontic archwires

    OpenAIRE

    Carlos Suárez; Teresa Vilar; Pablo Sevilla; Javier Gil

    2011-01-01

    To investigate the in vitro electrochemical corrosive behavior of archwires used in lingual orthodontics and the effects on the phase transition temperatures. Materials and Methods. Six different types of archwires of stainless steel, titanium-molybdenum, nickel-titanium and nickel-titanium-copper were used. Corrosion tests were performed following ISO-standard 10993-15:2000. Differential scanning calorimetry and scanning electron microscopy were used. Results. The stainless steel ar...

  9. Does orthodontic loading influence bone mineral density around titanium miniplates?

    DEFF Research Database (Denmark)

    Cornelis, Marie; Mahy, P; Devogelaer, J P; De Clerck, H J; Nyssen-Behets, C

    2010-01-01

    OBJECTIVES: To evaluate whether orthodontic loading has an effect on miniplate stability and bone mineral density (BMD) around the screws supporting those miniplates. SETTING AND SAMPLE POPULATION: Two miniplates were inserted in each jaw quadrant of 10 dogs. MATERIAL AND METHODS: Two weeks later, coil springs were placed between the miniplates of one upper quadrant and between those of the contralateral lower quadrant. The other miniplates remained non-loaded. The dogs were sacrificed 7 or 29 w...

  10. Treatment of Longitudinal Epiphyseal Bracket by Excision and Polymethylmethacrylate Insertion at the Preossified Disease Stage.

    Science.gov (United States)

    Bor, Noam; Rozen, Nimrod; Rubin, Guy

    2015-01-01

    Longitudinal epiphyseal bracket is a rare ossification anomaly involving the tubular bones of the hand or foot that have a proximal epiphysis, which becomes deformed as a result of the bracket. Untreated, the deformity becomes worse with age, because longitudinal growth cannot occur. The present report discusses the use of polymethylmethacrylate at the preossified disease stage in 2 patients with first metatarsal involvement. A medical record and radiographic review was performed for 2 children (3 feet), aged 1 year and 2 years and 5 months, who were treated with insertion of polymethylmethacrylate after excision of the aberrant epiphyseal bracket. Two different radiographic parameters (i.e., the intraosseous angulation and the metadiaphyseal length index) were used to measure the effect of treatment on the subsequent longitudinal growth of the metatarsals. An excellent clinical result after a long follow-up period was observed in 2 feet, and a good result was documented in 1 foot, which developed hallux valgus angulation. The use of polymethylmethacrylate as an interposition material after excision of the aberrant metatarsal epiphyseal bracket appeared to be an effective method of treatment during the preossified first stage of the disease, despite the general recommendation to use a cement spacer during the third ossified stage. Normal longitudinal growth of the metatarsals was noted without complications or risk of deformity recurrence. PMID:25441856

  11. RSRM nozzle actuator bracket/lug fracture mechanics qualification test

    Science.gov (United States)

    Kelley, Peggy

    1993-01-01

    This is the final report for the actuator bracket/lug fracture mechanics qualification test. The test plan (CTP-0071) outlined a two-phase test program designed to answer questions about the fracture criticality of the redesigned solid rocket motor (RSRM) nozzle actuator bracket. An analysis conducted using the NASA/FLAGRO fracture mechanics computer program indicated that the actuator bracket might be a fracture critical component. In the NASA/FLAGRO analysis, a simple lug model was used to represent the actuator bracket. It was calculated that the bracket would fracture if subjected to an actuator stall load in the presence of a 0.10 in. corner crack at the actuator attachment hole. The 0.10 in. crack size corresponds to the nondestructive inspection detectability limit for the actuator bracket. The inspection method used is the dye penetrant method. The actuator stall load (103,424 lb) is the maximum load which the actuator bracket is required to withstand during motor operation. This testing was designed to establish the accuracy of the analytical model and to directly determine whether the actuator bracket is capable of meeting fracture mechanics safe-life requirements.

  12. Derived bracket construction up to homotopy and Schroder numbers

    OpenAIRE

    Uchino, K

    2012-01-01

    We will introduce the notion of higher derived bracket construction in the category of operads and prove that the higher derived bracket construction of Lie operad is equivalent to the cobar construction of Leibniz operad. The theorem is proved by computing Schroder number.

  13. Corticotomy facilitated orthodontics: Review of a technique.

    Science.gov (United States)

    Alghamdi, Ali Saad Thafeed

    2010-01-01

    Corticotomy found to be effective in accelerating orthodontic treatment. The most important factors in the success of this technique is proper case selection and careful surgical and orthodontic treatment. Corticotomy facilitated orthodontics advocated for comprehensive fixed orthodontic appliances in conjunction with full thickness flaps and labial and lingual corticotomies around teeth to be moved. Bone graft should be applied directly over the bone cuts and the flap sutured in place. Tooth movement should be initiated two weeks after the surgery, and every two weeks thereafter by activation of the orthodontic appliance. Orthodontic treatment time with this technique will be reduced to one-third the time of conventional orthodontics. Alveolar augmentation of labial and lingual cortical plates were used in an effort to enhance and strengthen the periodontium, reasoning that the addition of bone to alveolar housing of the teeth, using modern bone grafting techniques, ensures root coverage as the dental arch expanded. Corticotomy facilitated orthodontics is promising procedure but only few cases were reported in the literature. Controlled clinical and histological studies are needed to understand the biology of tooth movement with this procedure, the effect on teeth and bone, post-retention stability, measuring the volume of mature bone formation, and determining the status of the periodontium and roots after treatment. PMID:23960473

  14. Comparative in vitro study for orthodontic adhesives relatively to sorption and solubility

    Science.gov (United States)

    Muntean, A.; Mesaros, A.; Festila, D.; Moldovan, M.; Boboia, S.; Mesaros, M.

    2015-12-01

    Water sorption and solubility correspond to undesirable physical characteristics because it may cause micro leakage and dissolution for composite materials used for orthodontic attachment bonding. The aim of this study was to evaluate the performance of four composite materials employed in orthodontic as adhesives, relatively to water and 50% alcoholic solution, by means of in vitro tests of sorption and solubility. We used an experimental composite sealer SO® (ICCRR Cluj Napoca) and 3 commercial products already on the market: Blugloo® (Ormco), Opal Bond MV® (Ultradent) and Bond It® (DB orthodontics). Data were recorded and specific statistic tests were performed, revealing significant differences for all materials relatively to tested solutions. The materials expressed an adequate performance in terms of sorption and solubility, offering various alternatives for orthodontists.

  15. Assessment of the mechanical properties of glass ionomer cements for orthodontic cementation

    Scientific Electronic Library Online (English)

    Marcel M., Farret; Eduardo Martinelli de, Lima; Eduardo Gonçalves, Mota; Hugo Mitsuo S., Oshima; Gabriela, Maguilnik; Patrícia Alves, Scheid.

    2012-12-01

    Full Text Available OBJETIVO: avaliar as propriedades mecânicas de três cimentos de ionômero de vidro (CIVs) utilizados para cimentação de anéis ortodônticos. MÉTODOS: foram utilizados dois CIVs convencionais (Ketac Cem Easy mix/3M-ESPE e Meron/Voco) e um CIV modificado por resina (Multi-Cure Glass ionomer/3M-Unitek). [...] Para os testes de resistência à compressão e tração diametral, foram confeccionados 12 corpos de prova de cada material. Para os testes de microdureza, foram confeccionados 15 corpos de prova de cada material; para os testes de resistência de união ao cisalhamento, foram utilizados 45 dentes bovinos incluídos em resina acrílica, sobre os quais foi cimentada uma lâmina de anel ortodôntico com braquete soldado a ela para a realização dos ensaios. Para os testes de compressão, tração diametral e cisalhamento, foi utilizada uma máquina universal de ensaios a uma velocidade de 1mm/min; para os testes de microdureza Vickers, foi utilizado um microdurômetro com 200g de carga durante 15 segundos. Os resultados foram submetidos à análise estatística ANOVA, complementada pelo teste de Tukey ao nível de significância de 5%. RESULTADOS: os resultados demonstraram que o Multi-Cure Glass Ionomer apresentou resistência à tração diametral significativamente maior (p Abstract in english OBJECTIVE: To evaluate the mechanical properties of three glass ionomers cements (GICs) used for band cementation in Orthodontics. METHODS: Two conventional glass ionomers (Ketac Cem Easy mix/3M-ESPE and Meron/Voco) and one resin modified glass ionomer (Multi-cure Glass ionomer/3M-Unitek) were selec [...] ted. For the compressive strength and diametral tensile strength tests, 12 specimens were made of each material. For the microhardness test 15 specimens were made of each material and for the shear bond strength tests 45 bovine permanent incisors were used mounted in a self-cure acrylic resin. Then, band segments with a welded bracket were cemented on the buccal surface of the crowns. For the mechanical tests of compressive and diametral tensile strength and shear bond strength a universal testing machine was used with a crosshead speed of 1,0 mm/min and for the Vickers microhardness analysis tests a Microdurometer was used with 200 g of load during 15 seconds. The results were submitted to statistical analysis through ANOVA complemented by Tukey's test at a significance level of 5%. RESULTS: The results shown that the Multi-Cure Glass Ionomer presented higher diametral tensile strength (p

  16. Corticotomy-assisted orthodontic treatment: review.

    Science.gov (United States)

    Hassan, Ali H; Al-Fraidi, Ahmad A; Al-Saeed, Samar H

    2010-01-01

    Corticotomy-assisted orthodontic treatment is an established and efficient orthodontic technique that has recently been studied in a number of publications. It has gradually gained popularity as an adjunct treatment option for the orthodontic treatment of adults. It involves selective alveolar decortication in the form of decortication lines and dots performed around the teeth that are to be moved. It is done to induce a state of increased tissue turnover and a transient osteopenia, which is followed by a faster rate of orthodontic tooth movement. This technique has several advantages, including faster tooth movement, shorter treatment time, safer expansion of constricted arches, enhanced post-orthodontic treatment stability and extended envelope of tooth movement. The aim of this article is to present a comprehensive review of the literature, including historical background, contemporary clinical techniques, indications, contraindications, complications and side effects. PMID:21228919

  17. Consequences of enamel preparation with sodium hypochlorite, polyacrylic and phosphoric acids for the bonding of brackets with resin-modified glass ionomer cements

    Scientific Electronic Library Online (English)

    Alessandra Marques, Trindade; Tatiana Bahia Junqueira, Pereira; Perrin, Smith Neto; Martinho Campolina Rebello, Horta; Matheus Melo, Pithon; Emílio, Akaki; Dauro Douglas, Oliveira.

    2013-12-01

    Full Text Available The aim of this study was to evaluate the effects of deproteinization with 5.25% sodium hypochlorite (NaOCl) prior to enamel conditioning with 10% polyacrylic acid (PAA) and 35% phosphoric acid (PA) on the bond strength (BS) of brackets bonded with resin-modified glass ionomer cement (RMGIC). One hu [...] ndred human premolars extracted for orthodontic reasons were divided into 5 groups (n = 20 in each group): G1 (control), enamel conditioning with PA, application of adhesive and bonding of brackets with TransbondTM XT composite resin (3M/Unitek, Monrovia, CA, USA); G2, enamel conditioning with PAA and bonding with RMGIC (Fuji OrthoTM LC, GC America, Alsip, IL, USA); G3, NaOCl-treated enamel, conditioning with PAA and bonding with RMGIC; G4, enamel conditioning with PA and bonding with RMGIC; and G5, NaOCl-treated enamel, conditioning with PA and bonding with RMGIC. Once the brackets were bonded, the teeth were stored in distilled water for 24 hours at room temperature and pressure until being subjected to shear stress in a Universal Mechanical Testing Machine (EMIC® DL 500, São José dos Pinhais, PR, Brazil). The BS value was higher in G1 (17.08 ± 6.39) than in any of the experimental groups (p 0.05), except between G3 (9.86 ± 2.90) and G5 (5.00 ± 2.49). No statistically significant differences were noted between the mean Adhesive Remnant Index values among the evaluated groups (p > 0.05). Conclusion: The use of NaOCl combined with PAA increased the BS of brackets bonded with RMGIC. The deproteinization of the group treated with PA reduced the shear bond strength of the brackets.

  18. Análise da qualidade de adesão de diferentes bases de braquetes metálicos Analysis of the adhesion quality of different metallic bracket bases

    Directory of Open Access Journals (Sweden)

    Danielle Morello Park

    2005-02-01

    Full Text Available Diante das diferenças existentes nas características das bases dos braquetes usados atualmente, objetivou-se neste trabalho comparar entre si três tipos de bases de braquetes metálicos (Monobloc, Equilibrium e Dynalock. Foram utilizados 36 pré-molares humanos, divididos em 3 grupos de 12 dentes. Os dentes foram incluídos em troquéis com gesso pedra tipo IV e posicionados com suas faces vestibulares perpendiculares à base do troquel. Todos os braquetes foram colados com o compósito Concise Ortodôntico e submetidos ao ensaio de cisalhamento em uma Máquina Universal com uma velocidade de 0,5 mm por minuto. O braquete Monobloc obteve o maior valor médio de resistência adesiva (x = 28,19 Kgf/cm², sendo superior estatisticamente aos braquetes Equilibrium (x = 18,07 Kgf/cm² e Dynalock (x = 18,24 Kgf/cm². Em relação ao ARI (Índice de Remanescente Resinoso, não foi encontrada diferença estatística entre os braquetes testados.Considering the differences in the bracket bases currently used, it was performed a study with the purpose of comparing three different metallic bracket bases commercially available. It was used 36 human bicuspids divided into 3 groups of 12 teeth. These teeth were immersed in a troquel with gypsy stone type IV and positioned with their buccal face perpendicular to the troquel base. For each group of teeth it was bonded one of the three brackets using Concise Orthodontic composite. Afterwards they were submitted to a shear bound strength test in a universal machine calibrated for a 0,5mm/minute speed. Monobloc bracket base showed the greater mean value of adhesive resistance (x = 28,19 Kgf/cm², result statistically superior to that shown by Equilibrium (x = 18,07 Kgf/cm² and Dynalock (x = 18,24 Kgf/cm² ones. The ARI (Adhesive reminiscent index showed no statistically difference among the bracket bases studied.

  19. Comparación de la Respuesta Biológica generada por un sistema de brackets Convencional y brackets de Autoligado.

    Directory of Open Access Journals (Sweden)

    Liseth Wilches Buitrago

    2014-09-01

    Full Text Available Antecedentes: No existe evidencia científica suficiente que soporte las ventajas del sistema de fuerzas de autoligado sobre el sistema de fuerzas convencional en ortodoncia. El objetivo de esta investigación  fue Comparar la expresión de OPG y RANKL en el ligamento periodontal de dientes sometido a fuerzas ortodóncicas generadas por un sistema de brackets de autoligado y un sistema convencional. Materiales y Métodos: Se analizó  la expresión de OPG y RANKL mediante RT-PCR en el  ligamento periodontal de 40 dientes con indicación de extracción terapéutica para ortodoncia. El grupo experimental estuvo conformado por  diez premolares que recibieron fuerzas con brackets de autoligado durante quince días  y diez premolares recibieron fuerzas  con brackets de arco recto durante 15 días antes de la extracción y 20 premolares sirvieron como grupo control. Los datos fueron analizados mediante la prueba de Kruskal–Wallis. Resultados: RANKL demostró un aumento estadísticamente significativo en el lado de presión de los dientes sometidos a los dos sistemas de fuerzas ortodóncicas. OPG no mostró diferencias entre las zonas o entre los dos sistemas de fuerzas analizados. Conclusiones: No se encontraron diferencias en la expresión de RANKL y OPG  en el ligamento periodontal de dientes movidos con técnica de ortodoncia de autoligado  comparados con los movidos con técnica de arco recto.

  20. Rapid Orthodontics with Flapless Piezoelectric Corticotomies: First Clinical Experiences / Ortodoncia Rápida con Corticotomías Piezoeléctricas sin Colgajo: Primeras Experiencias Clínicas

    Scientific Electronic Library Online (English)

    Jorge, Jofre; Julio, Montenegro; Roberto, Arroyo.

    Full Text Available Uno de los mayores desafíos que enfrenta un paciente de ortodoncia es el tiempo que lleva usar brackets. A través de los años, varias técnicas quirúrgicas se han desarrollado para hacer frente a este problema y reducir el tiempo total de tratamiento. Estas combinan los mecanismos de cicatrización ós [...] ea, con cargas de ortodoncia para acelerar el movimiento de los dientes. Aunque eficaz, estas técnicas son bastante invasivas, que requieren la elevación de colgajos bucales y linguales de espesor total con decorticaciones extensas del hueso alveolar bucal y lingual. Por otra parte, con estas técnicas se corre el riesgo de desvitalización dentaria, necrosis avascular del bloque óseo, reabsorción alveolar, y los riesgos de complicaciones, con baja aceptación por parte del paciente. Este trabajo reporta tres casos tratados con un nuevo enfoque sin colgajo para ortodoncia rápida mínimamente invasiva (MIRO - minimally invasive rapid orthodontic). Este procedimiento incluye microincisiones guiadas por radiografías y corticotomías piezoeléctricas localizadas. Las implicaciones clínicas de esta técnica se analizan en este documento. MIRO reduce el tiempo de tratamiento de ortodoncia, evitando los efectos adversos reportados por la ortodoncia acelerada. Abstract in english One of the biggest challenges an orthodontic patient faces is the time spent wearing brackets. Over the years, several surgical techniques have been developed to address this issue and reduce the overall treatment time. These combine bone-healing mechanisms with orthodontic loads to accelerate tooth [...] movement. Although effective, these techniques are also quite invasive in nature, requiring the elevation of buccal and lingual full-thickness flaps with extensive decortications of the buccal and lingual alveolar bone. Moreover, these techniques run the risk of teeth devitalization, avascular necrosis of the osseous block, alveolar resorption, and the risks of complications, with low acceptance by the patient. This manuscript reports three cases treated with a novel, flapless approach for minimally invasive rapid orthodontic (MIRO). This procedure includes radiographic-guided micro incisions and localized piezoelectric corticotomies. The clinical implications of this technique are discussed herein. MIRO reduces orthodontic treatment time, avoiding the reported adverse effects of accelerated orthodontics.

  1. Comparison of canine retraction using single and Siamese edgewise brackets: An in vivo study

    Directory of Open Access Journals (Sweden)

    Zeeshan Iqbal Bhat

    2013-01-01

    Full Text Available Objectives: The purpose of this study was to check the rate of canine retraction with bodily mechanics using two different pre-adjusted edgewise bracket Systems. Materials and Methods: A split mouth study with twenty patients who were randomly selected and allotted to a single operator. Duration of canine retraction, angulation of canine during its retraction, degree of Rotation, anchorage Loss, distance between canine and premolar at different time intervals were then evaluated, pre- (To, 3 months- (T1 and canine tip touches the second premolar- (T2. Descriptive statistics including mean values and standard deviations were calculated. Paired and unpaired t-test was performed to evaluate the differences between the groups. Results: Rotation and angulation of the canines did not show significant difference in both the systems. There was statistically significant difference (P<0.01 in anchorage loss between single wing and Siamese bracket being 2.65 ±1.41 mm and 1.31 ± 0.93 respectively. There was statistically significant intergroup difference (P<0.01 in canine movement i.e distance between canine and premolar was recorded as 4.72mm (15.06 ± 1.69 to 10.34 ± 1.68mm in single wing bracket and 6.25mm in Siamese (15.52 ± 1.41 to 9.27 ± 1.94. Conclusion: In cases where high anchorage is required and the rate of canine retraction is a concern, Siamese brackets pose a definite advantage over Single wing brackets.

  2. Finite element study on modification of bracket base and its effects on bond strength

    Scientific Electronic Library Online (English)

    Tarulatha R., Shyagali; Deepak P., Bhayya; Chandralekha B., Urs; Shashikala, Subramaniam.

    2015-04-01

    Full Text Available OBJETIVO: o objetivo do presente artigo é analisar a diferença entre as tensões geradas na interface braquete-cemento-dente por meio do teste peel load em bases de braquete de malha simples e dupla e do método de elementos finitos tridimensional. MÉTODOS: foi construído um modelo de elementos finit [...] os do sistema composto pela interface braquete-cemento-dente. Esse modelo consistiu de 40.536 nós e 49.201 elementos finitos. A análise foi feita com a ajuda do programa ANSYS 7.0. Tanto a base de braquete de malha única quanto a de malha dupla sofreram modificações no diâmetro, que variou de 100 a 400µm, progressivamente. O espaço entre os fios das malhas foi mantido a 300µm para o diâmetro de cada fio. O teste peel load foi aplicado ao modelo para investigar as tensões geradas nas diferentes camadas. RESULTADOS: quando comparadas às bases de braquetes de malha simples, as bases de braquetes de malha dupla geraram menos tensão no esmalte dentário. Não foram detectadas diferenças entre as tensões geradas na superfície dos braquetes com bases de malha simples e dupla. Na malha de fios impregnados (MFI), houve um aumento na tensão com o aumento do diâmetro dos fios que compõem a malha. CONCLUSÃO: os resultados revelam que as modificações no desenho do braquete podem aumentar a colagem e, ao mesmo tempo, minimizar os danos causados no esmalte durante o processo de descolagem. Esses fatos podem ser utilizados no desenvolvimento de desenhos de braquetes inovadores, destinados à utilização clínica. Abstract in english OBJECTIVE: This article aims to analyze the difference in stresses generated in the bracket-cement-tooth system by means of a peel load in single and double-mesh bracket bases using a three-dimensional finite element computer model. MATERIAL AND METHODS: A three-dimensional finite element model of [...] the bracket-cement-tooth system was constructed and consisted of 40,536 bonds and 49,201 finite elements using a commercial mesh generating programmer (ANSYS 7.0). Both single and double-mesh bracket bases were modified by varying the diameter from 100-400 µm progressively, and the spacing between the mesh wires was kept at 300 µm for each diameter of wire. A peel load was applied on the model to study the stresses generated in different layers. RESULTS: In case of double-mesh bracket base, there was reduction in stress generation at the enamel in comparison to single-mesh bracket base. There was no difference in stress generated at the bracket layer between single and double-mesh bracket bases. At the impregnated wire mesh (IWM), layer stresses increased as the wire diameter of the mesh increased. CONCLUSION: Results show that bracket design modification can improve bonding abilities and simultaneously reduce enamel damage while debonding. These facts may be used in bringing about the new innovative bracket designs for clinical use.

  3. Dentoalveolar mandibular changes with self-ligating versus conventional bracket systems: A CBCT and dental cast study

    Scientific Electronic Library Online (English)

    Marcio Rodrigues de, Almeida; Cristina, Futagami; Ana Cláudia de Castro Ferreira, Conti; Paula Vanessa Pedron, Oltramari-Navarro; Ricardo de Lima, Navarro.

    2015-06-01

    Full Text Available OBJETIVO: o objetivo do presente estudo foi comparar as alterações dentoalveolares transversais e a espessura óssea da arcada inferior em pacientes submetidos ao tratamento ortodôntico utilizando sistemas de braquetes autoligáveis ou convencionais. MÉTODOS: uma amostra de 25 pacientes requerendo tr [...] atamento ortodôntico foi recrutada com base no tipo de braquete. No Grupo 1, 13 pacientes foram tratados com braquetes autoligáveis (SLB, slot 0,022"); o Grupo 2 incluiu 12 pacientes, nos quais foram colados braquetes convencionais (CLB, slot 0,022"). Utilizou-se tomografia computadorizada de feixe cônico e um programa 3D (Dolphin) para avaliar as alterações pré-tratamento (T1) e 7 meses após o início desse (T2). As medições em modelos de gesso foram realizadas com o auxílio de um paquímetro digital. As diferenças intergrupos, bem como intragrupo, foram analisadas por meio de teste t de Student. Além disso, o coeficiente de correlação de Pearson foi utilizado. RESULTADOS: alterações dentoalveolares significativas foram observadas em ambos os grupos. Entretanto, não houve diferenças significativas entre os grupos. Houve uma diminuição da espessura óssea na região posterior e das medidas transversais em ambos os grupos. Não houve uma correlação significativa entre a espessura óssea posterior e a expansão da arcada dentária, em nenhum dos dois sistemas de braquetes utilizados. CONCLUSÕES: comparando-se o uso dos aparelhos autoligáveis e convencionais, concluiu-se que não houve diferenças dentoalveolares significativas quanto à expansão da arcada inferior e quanto à espessura óssea posterior. Abstract in english OBJECTIVE: The aim of the present study was to compare dentoalveolar changes in mandibular arch, regarding transversal measures and buccal bone thickness, in patients undergoing the initial phase of orthodontic treatment with self-ligating or conventional bracket systems. METHODS: A sample of 25 pa [...] tients requiring orthodontic treatment was assessed based on the bracket type. Group 1 comprised 13 patients bonded with 0.022-in self-ligating brackets (SLB). Group 2 included 12 patients bonded with 0.022-in conventional brackets (CLB). Cone-beam computed tomography (CBCT) scans and a 3D program (Dolphin) assessed changes in transversal width of buccal bone (TWBB) and buccal bone thickness (BBT) before (T1) and 7 months after treatment onset (T2). Measurements on dental casts were performed using a digital caliper. Differences between and within groups were analyzed by Student's t-test; Pearson correlation coefficient was also calculated. RESULTS: Significant mandibular expansion was observed for both groups; however, no significant differences were found between groups. There was significant decrease in mandibular buccal bone thickness and transversal width of buccal bone in both groups. There was no significant correlation between buccal bone thickness and dental arch expansion. CONCLUSIONS: There were no significant differences between self-ligating brackets and conventional brackets systems regarding mandibular arch expansion and changes in buccal bone thickness or transversal width of buccal bone.

  4. Effect of Different Surface Treatments for Ceramic Bracket Base on Bond Strength of Rebonded Brackets

    Scientific Electronic Library Online (English)

    Monique Kruger, Guarita; Alexa Helena Köhler, Moresca; Estela Maris, Losso; Alexandre, Moro; Ricardo Cesar, Moresca; Gisele Maria, Correr.

    2015-02-01

    Full Text Available O objetivo do estudo foi avaliar o efeito de tratamentos da base de bráquetes cerâmicos monocristalinos na resistência de união ao esmalte após recolagem. Setenta e cinco pré-molares foram selecionados e aleatoriamente distribuídos em 5 grupos (n=15) de acordo com o tratamento da base do bráquete: I [...] - sem tratamento, primeira colagem (controle), II - jateamento com óxido de alumínio, III - jateamento seguido da aplicação de silano, IV - jateamento com partículas de dióxido de sílica (silicatização) seguido de silano, V - silicatização realizada em laboratório (Sistema Rocatec). Os bráquetes foram colados no esmalte com Transbond XT sem condicionamento ácido. Em seguida, os bráquetes foram removidos e suas bases foram submetidas aos diferentes tratamentos. Os bráquetes foram recolados, armazenados por 24 h e submetidos ao ensaio mecânico de cisalhamento com velocidade de 0,5 mm/min. Após, o índice de remanescente adesivo (IRA) foi avaliado em cada espécime. Os dados foram submetidos à análise de variância e teste de Tukey (?=0,05). Pode-se observar que houve diferença significativa apenas entre o sistema Rocatec e os demais grupos, o qual apresentou os menores valores de resistência. Os maiores valores de resistência foram observados para o grupo I (controle), sem diferença significativa dos grupos II, III e IV. A maioria dos grupos apresentou maior porcentagem de falhas na interface esmalte/resina (escore 1). Pode-se concluir que os tratamentos da base do bráquete cerâmico foram efetivos, apresentando valores similares ao grupo controle, exceto para o grupo em que foi usado Rocatec. Abstract in english The aim of this study was to evaluate the shear bond strength of rebonded ceramic brackets after subjecting the bracket base to different treatments. Seventy-five premolars were selected and randomly distributed into five groups (n=15), according to the type of the bracket surface treatment: I, no t [...] reatment, first bonding (control); II, sandblasting with aluminum oxide; III, sandblasting + silane; IV, silica coating + silane; and V, silicatization performed in a laboratory (Rocatec system). The brackets were fixed on an enamel surface with Transbond XT resin without acid etching. The brackets were then removed and their bases were subjected to different treatments. Thereafter, the brackets were fixed again to the enamel surface and the specimens were subjected to shear bond strength (SBS) test. The adhesive remnant index (ARI) was then evaluated for each specimen. Data were subjected to ANOVA and Tukey's tests (?=0.05). A statistically significant difference was observed only between Rocatec and the other groups; the Rocatec group showed the lowest SBS values. The highest SBS values were observed for group 1, without any significant difference from the values for groups II, III and IV. Most groups had a higher percentage of failures at the enamel-resin interface (score 1). It was concluded that the surface treatments of rebonded ceramic brackets were effective, with SBS values similar to that of the control group, except Rocatec group.

  5. Association between gingivitis and anterior gingival enlargement in subjects undergoing fixed orthodontic treatment

    Scientific Electronic Library Online (English)

    Fabricio Batistin, Zanatta; Thiago Machado, Ardenghi; Raquel Pippi, Antoniazzi; Tatiana Militz Perrone, Pinto; Cassiano Kuchenbecker, Rösing.

    2014-06-01

    Full Text Available OBJETIVO: o objetivo desse estudo foi verificar a associação entre volume gengival (AG) com condições periodontais e características sócio-demográficas em sujeitos com aparelho ortodônticos fixo. MÉTODOS: uma amostra, de 330 participantes com aparelho ortodôntico fixo, por pelo menos seis mese [...] s, foi examinada, por um único examinador calibrado, para os índices de placa e gengivais, profundidade de sondagem, nível de inserção clínico e aumento de volume gengival. O status socioeconômico, tempo com aparelho ortodôntico fixo e uso de fio dental foram verificados por entrevista oral. A verificação das associações foi realizada por meio de modelos de regressão de Poisson sem ajuste e ajustados. RESULTADOS: a presença de sangramento gengival (RR 1.01; 95% IC 1.00-1.01) e o excesso de resina em torno dos braquetes (RR 1.02; 95% IC 1.02-1.03) foram associadas a um aumento do AG. Não foram encontradas associações entre características sócio-demográficas e AG. CONCLUSÃO: sangramento gengival proximal na região anterior e excesso de resina no entorno dos braquetes estão associados a níveis mais altos de aumento de volume gengival na região anterior em sujeitos com aparelho ortodôntico fixo. Abstract in english OBJECTIVE: The aim of this study was to investigate the association among gingival enlargement (GE), periodontal conditions and socio-demographic characteristics in subjects undergoing fixed orthodontic treatment. METHODS: A sample of 330 patients undergoing fixed orthodontic treatment for at [...] least 6 months were examined by a single calibrated examiner for plaque and gingival indexes, probing pocket depth, clinical attachment loss and gingival enlargement. Socio-economic background, orthodontic treatment duration and use of dental floss were assessed by oral interviews. Associations were assessed by means of unadjusted and adjusted Poisson's regression models. RESULTS: The presence of gingival bleeding (RR 1.01; 95% CI 1.00-1.01) and excess resin around brackets (RR 1.02; 95% CI 1.02-1.03) were associated with an increase in GE. No associations were found between socio-demographic characteristics and GE. CONCLUSION: Proximal anterior gingival bleeding and excess resin around brackets are associated with higher levels of anterior gingival enlargement in subjects under orthodontic treatment.

  6. Design manual for HANARO in-chimney bracket

    Energy Technology Data Exchange (ETDEWEB)

    Ryu, Jeong Soo; Cho, Y. G.; Whang, S. Y.; Wu, J. S.; Jun, B. J

    2000-06-01

    As a supplementary structure supporting the irradiation facilities, the in-chimney bracket holds guide tubes whose holding position in CT or IR is the middle part of the instrumented facility between the hole spider and the robot arm already provided in the reactor pool liner. Also, the bracket grips the upper part of the guide tubes when it is applied to hold the instrumented facility loaded in OR sites. The irradiation test will be successfully conducted since this bracket reduces the flow-induced vibration (FIV) and the dynamic response to seismic load. The installation position of the bracket is 60 cm below the top of the chimney, i.e., thermo siphoning hole position. To evaluate the structural integrity on the in-chimney bracket and the related reactor structures, ANSYS finite element analysis model is developed and the dynamic characteristics are analyzed. The seismic response analyses were performed for the in-chimney bracket and the related reactor structures of HANARO under the design earthquake response spectrum loads of OBE and SSE. The analysis results show that the stress values in main points of reactor structures and in-chimney bracket for the seismic loads are also within the ASME code limits. It is also confirmed that the fatigue usage factor is much less than 1.0. Therefore any damage on structural integrity is not expected when the in-chimney bracket is installed at the upper part of the reactor chimney. This bracket had been designed and manufactured based on the dimensions of the as-built chimney. In the process of design and preliminary installation, chimney measurement tools, dummy chimney, and installation tools were developed and the installation procedure was prepared and verified through the installation rehearsal.

  7. Periodontally accelerated osteogenic orthodontics (PAOO) - a review.

    Science.gov (United States)

    Amit, Goyal; Jps, Kalra; Pankaj, Bhatiya; Suchinder, Singla; Parul, Bansal

    2012-12-01

    With an increasing number of adult patients coming to the orthodontic clinic, the orthodontic professional is constantly looking for ways to accelerate tooth movement. Surgical intervention to affect the alveolar housing and tooth movement has been described in various forms for over a hundred years. However, it is the spirit of interdisciplinary collaboration in orthodontics has expanded the realm of traditional orthodontic tooth movement protocols. Periodontal accelerated osteogenic orthodontics (PAOO) is a clinical procedure that combines selective alveolar corticotomy, particulate bone grafting, and the application of orthodontic forces. This procedure is theoretically based on the bone healing pattern known as the regional acceleratory phenomenon (RAP). PAOO results in an increase in alveolar bone width, shorter treatment time, increased post treatment stability, and decreased amount of apical root resorption. Tooth movement can be enhanced and cases completed with increased alveolar volume providing for a more intact periodontium, decreased need for extractions, degree of facial remodeling and increased bone support for teeth and overlying soft tissues, thereby augmenting gingival and facial esthetics.The purpose of this article is to describe the history, biology, clinical surgical procedures, indications, contraindications and possible complications of the PAOO procedure. Key words:Periodontics, corticotomy, osteogenic, orthodontics. PMID:24455038

  8. Orthodontic Force Induces Systemic Inflammatory Monocyte Responses.

    Science.gov (United States)

    Zeng, M; Kou, X; Yang, R; Liu, D; Wang, X; Song, Y; Zhang, J; Yan, Y; Liu, F; He, D; Gan, Y; Zhou, Y

    2015-09-01

    Periodontal inflammation and alveolar bone remodeling during orthodontic tooth movement are considered regional reactions. However, how systemic immune responses are involved in this regional reaction remains unclear. In this study, we explored the systemic effects of orthodontic force by focusing on the mononuclear phagocyte system. Flow cytometric analysis showed that the percentage of inflammatory monocytes, in peripheral blood and in the monocyte reservoir spleen, decreased on days 1 and 3 and then recovered on day 7 after force application. Along with the systemic decrease of inflammatory monocyte percentage, the number of tartrate-resistant acid phosphatase-positive osteoclasts increased in the compression side of the periodontal tissue during orthodontic tooth movement. Systemic transfusion of enhanced green fluorescent protein-labeled inflammatory monocytes showed recruitment of these monocytes to the orthodontic force compression side of periodontal tissues. These monocytes were colocalized with tartrate-resistant acid phosphatase-positive osteoclasts. In vivo and in vitro experiments showed that orthodontic force could upregulate the expression of pivotal monocyte chemokine monocyte chemotactic protein 1 in periodontal tissues or cultured periodontal ligament cells, which may contribute to monocyte recruitment to regional sites. These data suggest that orthodontic force induces systemic immune responses related to inflammatory monocytes and that systemic inflammatory monocytes can be recruited to periodontal tissues by orthodontic force stimulus. PMID:26130260

  9. Tax bracket creep and its effects on income distribution

    OpenAIRE

    Heer, Burkhard; Süssmuth, Bernd

    2013-01-01

    We quantitatively analyze the way inflation alters the inequality of the income distribution in the U.S. economy. The main mechanism emphasized in this paper is the bracket creep effect according to which inflation pushes income into higher tax brackets. Governments adjust the nominal income tax brackets slowly and incompletely due to the rise in prices. In the U.S. postwar history, this typically happens less often than once every other tax year. In the first part of the paper, we study time...

  10. Effect of orthodontic debonding and adhesive removal on the enamel - current knowledge and future perspectives - a systematic review.

    Science.gov (United States)

    Janiszewska-Olszowska, Joanna; Szatkiewicz, Tomasz; Tomkowski, Robert; Tandecka, Katarzyna; Grocholewicz, Katarzyna

    2014-01-01

    After orthodontic treatment, brackets are debonded and residual adhesive is removed, causing iatrogenic enamel damage. The aim of this study was to review the methods of orthodontic adhesive removal, find clear evidence, and provide a rationale for this procedure. A literature search was performed in PubMed, Dentistry and Oral Sciences, Scopus, Cochrane, Google, and Google Scholar using keywords: orthodontic adhesive removal, orthodontic debonding, orthodontic clean-up. Studies concerning human enamel roughness or loss from debonding and adhesive removal were considered. Forty-four full-text articles were analyzed and 3 were rejected after detailed reading; finally 41 papers were included. Fifteen qualitative studies, 13 studies based on indices of enamel surface, and 13 quantitative studies were found. No meta-analysis could be performed due to a lack of homogenous quantitative evidence. The most popular tools were tungsten carbide burs, which were faster and more effective than Sof-Lex discs, ultrasonic tools, hand instruments, rubbers, or composite burs. They remove a substantial layer of enamel and roughen its surface, but are less destructive than Arkansas stones, green stones, diamond burs, steel burs, and lasers. Multi-step Sof-Lex discs and pumice slurry are the most predictable enamel polishing tools. Arkansas stones, green stones, diamond burs, steel burs, and lasers should not be used for adhesive removal. The use of tungsten carbide bur requires multistep polishing. Further efforts should be made to find tools and methods for complete removal of adhesive remnants, minimizing enamel loss and achieving a smooth surface. PMID:25327612

  11. Patients’ acceptance of corticotomy-assisted orthodontics

    Directory of Open Access Journals (Sweden)

    Zawawi KH

    2015-08-01

    Full Text Available Khalid H Zawawi Department of Orthodontics, Faculty of Dentistry, King Abdulaziz University, Jeddah, Saudi Arabia Objective: To study patients’ acceptance of corticotomy-assisted orthodontics as a treatment option.Methods: Adult patients seeking orthodontic treatment were asked to complete two sets of questionnaires; the first set included questions about age, sex, and level of education and general questions about orthodontic treatment; and the second set was related to the corticotomy-assisted orthodontics. Before answering the corticotomy questions, a brief description of the clinical procedure was explained and photographs of an actual procedure were shown.Results: A total of 150 subjects were approached and 129 (86% agreed to answer the questionnaires (72 male and 57 female patients. Of these, only 3.1% did hear about corticotomy and 7.8% selected corticotomy instead of extraction. Fear from the surgery (53.2% was the most frequent reason for not selecting corticotomy followed by fear from pain (36.9%. The acceptance of corticotomy between males and females was similar. No relationship was found between the level of education and prior knowledge of the procedure, P=0.857. Prior knowledge about corticotomy was not a factor in selecting it as a treatment option (P=0.556 to reduce the treatment time (P=0.427.Conclusion: The acceptance of corticotomy-assisted orthodontics as a treatment option was low. Fear from the surgery was the main reason for not selecting it. The acceptance of corticotomy-assisted orthodontics was not related to patient’s level of education or sex. Keywords: orthodontic treatment, corticotomy-assisted orthodontics, patient acceptance, cross sectional survey, alveolar decortication

  12. Radiographic evaluation of apical root resorption following fixed orthodontic treatment

    Directory of Open Access Journals (Sweden)

    Sina Haghanifar

    2012-01-01

    Full Text Available Background and Aims: Apical root resorption is an adverse side effect of fixed orthodontic treatment which cannot be repaired. The aim of this study was to use panoramic radiographs to compare the root resorption before and after the orthodontic treatment with standard edgewise .018 appliance.Materials and Methods: The before and after treatment panoramic views of sixty-three patients needed fixed orthodontic treatment included 1520 teeth were categorized into 3 Grades (G0: without resorption, G1: mild resorption with blunt roots or ? 1/4 of root length, G2: moderate to severe resorption or > 1/4 to 1/2 of root length. Relationship between root resorption and sex and treatment duration was analyzed with Mann-whitney and Spearman's correlation coefficient, respectively.Results: The findings showed that 345 teeth were categorized as Grade 1. Grade 2 of root resorption was not found in this study. The highest amount of root resorption was recorded for the mandibular lateral incisor. In both gender, the root resorption of the mandible was more than that of the maxilla. The males showed significantly higher rate of resorption than the females (P0.05.Conclusion: The mandible and male patients showed higher amount of root resorption. In addition, root resorption was not related to the treatment duration and the side of the jaws.

  13. Labio-lingual root control of lower anterior teeth and canines obtained by active and passive self-ligating brackets

    DEFF Research Database (Denmark)

    Cattaneo, Paolo M; Salih, Raaid A

    2013-01-01

    Abstract Objective: To investigate the torque capabilities of passive and active self-ligating (SL) brackets on mandibular incisors and canines using three-dimensional (3D) imaging analysis. Materials and Methods: Two types of SL bracket systems were analyzed: a passive and an active. Both brackets had a 0.022 × 0.028-inch slot size. Treatment protocol and wire sequences were followed as recommended by the manufacturers. Twenty-six patients were included in the passive group and 20 were included in the active group; all received pretreatment and posttreatment cone-beam computed tomography (CBCT) scanning. Based on the CBCT scans, a customized 3D analysis was developed to assess labiolingual inclination of the roots of mandibular canines and incisors with respect to the occlusal plane before and after treatment. Results: Following treatment, a statistically significant labiolingual proclination of the teeth was seen in both groups. Moreover, in both SL systems the roots exhibited a large variation in labiolingual inclination between adjacent teeth even after treatment. Conclusions: A significant proclination was seen for the mandibular front teeth; the claimed third-order torque control of SL systems could not be demonstrated. Therefore, a considerable play between the wire and the brackets could be hypothesized, even more in relation to the passive than the active SL brackets.

  14. Ortodoncia acelerada y ortodoncia de transito expreso (OTE)®, un concepto contemporáneo de alta eficiencia / Accelerated orthodontics and express transit orthodontics (ETO)®, a contemporary concept of high efficiency

    Scientific Electronic Library Online (English)

    Juan Fernando, Aristizábal-P.

    2014-06-01

    Full Text Available Resumen Acelerar un tratamiento de Ortodoncia permite disminuir los riesgos naturales de desmineralización del esmalte, compromiso periodontal y reabsorción radicular, además de contribuir a tener pacientes mas satisfechos y profesionales con consultas mas eficientes. Varios métodos se han evaluado [...] para mejorar la rata, magnitud y estabilidad del movimiento ortodóncico, entre ellos están, abordajes quirúrgicos, bioquímicos, farmacológicos y terapia con láser. Por otro lado, en el panorama mecánico, la evolución de los sistemas de brackets ha permitido que lleguen al mercado sistemas contemporáneos que garantizan mejores abordajes biológicos por lo menos desde el punto de vista de niveles de fuerza. La sumatoria de aproximaciones diagnósticas de alta calidad, mecanoterapias eficientes y complementos de orden físico y/o biológico y quirúrgico para acelerar los movimientos es lo que llamamos Ortodoncia de Tránsito Expreso (OTE)®, la cual es una alternativa importante para tratamientos de alta calidad y eficiencia. El propósito de esta revisión de literatura, es analizar las nuevas aproximaciones para acelerar el movimiento dentario desde el abordaje biológico, físico y quirúrgico, en sinergia con un complemento mecánico, ya sea con sistemas de Autoligado pasivo convencional o personalizado Abstract in english Accelerated Orthodontic treatment can reduce risks of enamel demineralization, root resorption and periodontal problems, and contribute to have more satisfied patients and professionals with more efficient practices. Several methods have been evaluated to improve the rate, magnitude and stability of [...] orthodontic movement, which include surgical, biochemical, pharmacological and laser therapy approaches. Furthermore, in the mechanical scope, the evolution of brackets systems has allowed contemporary systems to reach the market which guarantee better biological approaches at least from the point of view of strength levels. The sum of high quality diagnostic approaches, efficient mechanics and physical and / or biological and surgical accessories in order to accelerate the movement is what we call Express Transit Orthodontics (OTE)®, which is an important alternative for high quality and efficient treatments. The purpose of this literature review is to analyze new approaches to accelerate tooth movement from the biological, physical and surgical approach, in synergy with a mechanical complement, either conventional or customized self-ligature systems

  15. Analysis of Bracket Assembly for Portable Leak Detector Station

    International Nuclear Information System (INIS)

    This Supporting Document Presents Structural and Stress Analysis of a Portable Leak Detector Station for Tank Farms. The results show that the bracket assembly meets the requirements for dead load and natural phenomena hazards loads (seismic and wind)

  16. A twisted generalization of linear Poisson brackets of hydrodynamic type

    International Nuclear Information System (INIS)

    We study a twisted generalization of linear Poisson brackets of hydrodynamic type, in which the Lie bracket is replaced by a Hom-Lie bracket. With some natural additional conditions, such structures correspond to the Hom-Novikov algebras introduced by Yau, which is the twisted version of Balinsky-Novikov's approach of constructing a Lie algebra from a Novikov algebra. Certain central extensions of this twisted generalization of linear Poisson brackets of hydrodynamic type are obtained from the bilinear forms on their corresponding Hom-Novikov algebras satisfying some invariance conditions. Finally, we give some examples of the infinite-dimensional Hom-Lie algebras constructed from the Hom-Novikov algebras. In particular, there is an interesting twisted generalization of the Virasoro algebra.

  17. Time-dependent constrained Hamiltonian systems and Dirac brackets

    International Nuclear Information System (INIS)

    In this paper the canonical Dirac formalism for time-dependent constrained Hamiltonian systems is globalized. A time-dependent Dirac bracket which reduces to the usual one for time-independent systems is introduced. (author)

  18. Time-dependent constrained Hamiltonian systems and Dirac brackets

    Energy Technology Data Exchange (ETDEWEB)

    Leon, Manuel de [Instituto de Matematicas y Fisica Fundamental, Consejo Superior de Investigaciones Cientificas, Madrid (Spain); Marrero, Juan C. [Departamento de Matematica Fundamental, Facultad de Matematicas, Universidad de La Laguna, La Laguna, Tenerife, Canary Islands (Spain); Martin de Diego, David [Departamento de Economia Aplicada Cuantitativa, Facultad de Ciencias Economicas y Empresariales, UNED, Madrid (Spain)

    1996-11-07

    In this paper the canonical Dirac formalism for time-dependent constrained Hamiltonian systems is globalized. A time-dependent Dirac bracket which reduces to the usual one for time-independent systems is introduced. (author)

  19. Orthodontic Management of a Severely Rotated Maxillary Central Incisor in the Mixed Dentition: A Case Report

    Directory of Open Access Journals (Sweden)

    Arezoo Jahanbin

    2014-06-01

    Full Text Available The aim of this case report was to introduce an appliance for correcting severe rotation of anterior teeth in the mixed dentition period. A 9-year-old Iranian boy with a mixed dentition Class I malocclusion complained of a severely rotated of upper right central incisor. There was a mesiodens between the central incisors. The supernumerary tooth was first extracted and then a Whip appliance which is composed of a removable plate, a cantilever spring and a central bracket on the rotated tooth was utilized. After 8 months, the upper right central incisor was orthodontically brought into proper alignment. Circumferential supracrestal fibrotomy was performed on the overcorrected tooth. One week after surgery, the device was removed and the retention was started. The whip appliance is a removable appliance that can effectively correct severe rotation of anterior teeth especially during the mixed dentition period.

  20. In vitro properties of orthodontic adhesives with fluoride or amorphous calcium phosphate.

    Science.gov (United States)

    Chow, Clara Ka Wai; Wu, Christine D; Evans, Carla A

    2011-01-01

    This in vitro study evaluated the efficacy of orthodontic adhesives with fluoride or amorphous calcium phosphate (ACP) in reducing bacterial adhesion and enamel demineralization. Forty human premolars each sectioned buccolingually into three parts were bracketed with control resin (Transbond XT) or adhesives containing ACP (Aegis Ortho) or fluoride (QuickCure). Artificial lesions induced by pH cycling were examined by X-ray photoelectron spectrophotometry (XPS) and polarized light microscopy (PLM). After 28 days, Aegis Ortho demonstrated the lowest calcium and phosphorous content by XPS analysis. After 42 days, reductions in lesion depth areas were 23.6% for Quick Cure and 20.3% for Aegis Ortho (P adhesion of Streptococcus mutans to Aegis Ortho and Quick Cure was reduced by 41.8% and 37.7% (P Composites containing ACP or fluoride reduced bacterial adherence and lesion formation as compared to a composite without ACP or fluoride. PMID:21912546

  1. Biophysical parameters of the oral fluid and cells of the buccal epithelium in children with diseases of the thyroid gland in the course of orthodontic treatment of maxillodental anomalies

    Directory of Open Access Journals (Sweden)

    Kolesnik K.A.

    2014-03-01

    Full Text Available The thyroid status disturbance may be reflected on the biological processes which underlie orthodontic tooth movement. Aim of research – to study state of the oral fluid and buccal epithelium cells (BEC in the course of a complex orthodontic treatment of children with thyroid gland diseases. In 79 children with a diffuse nontoxic goiter (DNG of the I-III degrees, stability of oral fluid pH (?pH, rate of mobile nuclei of BEC, ratio of electrophoretic displacement range of nuclei and plasmolemms was estimated. Estimation of corresponding parameters in the initial state, in 1, 3, 6 and 8 months after fixation of the fixed orthodontic apparatus was carried out. Children of the basic group according to pathology degree in addition received a prophylactic complex including preparations: “Vitrum Perfomens", "Teraflex", "Kalcicor", «Potassium iodide», «Echinacea compositum C», "Lizodent", "Osteobios". Ap¬plication of the prophylactic complex in orthodontic treatment of children with DNG prevented growth of ??? after fixation of brackets. Throughout all time of supervision it promoted reduction of this rate which slightly exceeded average rate for the given age of children in 8 months. Application of this prophylactic complex already in 1 month after fixation of brackets has raised quantity of mobile BEC nuclei by 44% and by 1,64 times has increased the relation of ranges of plasmolemms and nuclei displacement. In 8 months of supervision percent of mobile nuclei BEC and the relation of Apl/Aya in the basic group was by 2 times more, than in a comparison group, approaching to average rate. ?hildren with thyroid gland diseases need active treatment-and-prophylactic measures at stages of active apparatus treatment. The developed therapeutic complexes of orthodontic treatment of maxillo-dental anomalies in children with DNG allows to effectively support and improve functional reactions in the organism and in the oral cavity, compensating stressful action of fixed orthodontic apparatuses.

  2. In vitro tooth cleaning efficacy of electric toothbrushes around brackets

    OpenAIRE

    Schätzle, M; Sener, B.; Schmidlin, P R; Imfeld, T; Attin, T.

    2010-01-01

    This in vitro study assessed the cleaning efficacy of different electric toothbrushes around upper incisor brackets. Standard and Mini Diamond™ brackets were fixed on black-stained teeth. The teeth were coated with white titanium oxide and brushed in a machine twice for 1 minute each. Twelve different brush heads with either a wiping or an oscillating-rotating action were tested. After brushing, the teeth were scanned, the black surfaces were assessed planimetrically and a modified plaque ind...

  3. Iterative learning extremum seeking tracking via Lie bracket approximation

    OpenAIRE

    Cao, Zhixing; Dürr, Hans-Bernd; Ebenbauer, Christian; Allgöwer, Frank; Gao, Furong

    2015-01-01

    In this paper, we develop an extremum seeking control method integrated with iterative learning control to track a time-varying optimizer within finite time. The behavior of the extremum seeking system is analyzed via an approximating system - the modified Lie bracket system. The modified Lie bracket system is essentially an online integral-type iterative learning control law. The paper contributes to two fields, namely, iterative learning control and extremum seeking. First...

  4. Corrosion behavior of self-ligating and conventional metal brackets

    Science.gov (United States)

    Maia, Lúcio Henrique Esmeraldo Gurgel; Lopes Filho, Hibernon; Ruellas, Antônio Carlos de Oliveira; Araújo, Mônica Tirre de Souza; Vaitsman, Delmo Santiago

    2014-01-01

    Objective To test the null hypothesis that the aging process in self-ligating brackets is not higher than in conventional brackets. Methods Twenty-five conventional (GN-3M/Unitek; GE-GAC; VE-Aditek) and 25 self-ligating (SCs-3M/Unitek; INs-GAC; ECs-Aditek) metal brackets from three manufacturers (n = 150) were submitted to aging process in 0.9% NaCl solution at a constant temperature of 37 ± 1ºC for 21 days. The content of nickel, chromium and iron ions in the solution collected at intervals of 7, 14 and 21 days was quantified by atomic absorption spectrophotometry. After the aging process, the brackets were analyzed by scanning electron microscopy (SEM) under 22X and 1,000X magnifications. Results Comparison of metal release in self-ligating and conventional brackets from the same manufacturer proved that the SCs group released more nickel (p < 0.05) than the GN group after 7 and 14 days, but less chromium (p < 0.05) after 14 days and less iron (p < 0.05) at the three experimental time intervals. The INs group released less iron (p < 0.05) than the GE group after 7 days and less nickel, chromium and iron (p < 0.05) after 14 and 21 days. The ECs group released more nickel, chromium and iron (p < 0.05) than the VE group after 14 days, but released less nickel and chromium (p < 0.05) after 7 days and less chromium and iron (p < 0.05) after 21 days. The SEM analysis revealed alterations on surface topography of conventional and self-ligating brackets. Conclusions The aging process in self-ligating brackets was not greater than in conventional brackets from the same manufacturer. The null hypothesis was accepted. PMID:24945521

  5. Generalized Poisson brackets for discrete and continuous systems

    International Nuclear Information System (INIS)

    Generalized Poisson Brackets are discussed following closely the book of Sudarshan and Mubunda without going into the formalism of symplectic forms. It is found that there are rather drastic differences between discrete and continuous systems, especially with respect to fulfillment of Jacobi identity. Examples are given for the continuous case, and the relation of the brackets to Lagrangian derivation, Liouville theorem and Lie groups are explained. Applications, especially in plasma physics, are mentioned. (orig.)

  6. ORTHODONTIC MANAGEMENT IN CHILDREN WITH SPECIAL NEEDS

    Directory of Open Access Journals (Sweden)

    Adit ARORA

    2013-07-01

    Full Text Available Special needs individuals are children or adults pre? vented by a physical or mental condition permitting their full participation to the normal range of activities of their age groups. They usually exhibit high orthodontic treat? ment needs because of an increased prevalence and seve? rity of malocclusions. These conditions often require a coordinated craniofacial orthodontic and surgical treat? ment in a team setting, to achieve optimal outcome. Ort? hodontic treatments for patients born with facial differences tend to be more complex than ordinary ortho? dontics. This multidisciplinary treatment often starts from birth and extends up to the late teen years. The young patient may require treatment by multiple specialists, including a craniofacial surgeon, pediatrician, geneticist, neurosurgeon, ENT, speech and language therapist, pedi? atric dentist, oral surgeon and prosthodontist. The objec? tive of this paper is to summarize protocols of orthodontic treatment and to present various orthodontic management protocols regarding the children with special needs.

  7. Insights into the business of orthodontics.

    Science.gov (United States)

    Venn, V; Scott, S

    1996-08-01

    This article explores the key aspects of business planning and management which are most appropriate for the successful orthodontic practice. It is written by consultants who are experienced in helping individual practices achieve personal and professional goals. PMID:8894163

  8. ORTHODONTIC MANAGEMENT IN CHILDREN WITH SPECIAL NEEDS

    OpenAIRE

    Adit ARORA; Amit PRAKASH

    2013-01-01

    Special needs individuals are children or adults pre? vented by a physical or mental condition permitting their full participation to the normal range of activities of their age groups. They usually exhibit high orthodontic treat? ment needs because of an increased prevalence and seve? rity of malocclusions. These conditions often require a coordinated craniofacial orthodontic and surgical treat? ment in a team setting, to achieve optimal outcome. Ort? hodontic treatments for patients born wi...

  9. Clinical applications of magnets in orthodontics.

    OpenAIRE

    M. A. Papadopoulos

    1999-01-01

    Rare earth magnets, especially the samarium-cobalt (SmCo5, Sm2Co17) and neodymium-iron-boron (Nd2Fe14B) types, have many applications in orthodontics. They can be used to move teeth, to expand the upper dental arch, to correct Class II and Class III malocclusions combined with functional appliances and to retain the therapeutic results achieved. Although the superiority of treatment results with various magnetic appliances in comparison to the conventional orthodontic appliances is supported ...

  10. Lingual Orthodontics simplified : Incognito -customization perfected

    OpenAIRE

    Haroutioun Dedeyan; Revankar, Ameet V

    2013-01-01

    Esthetic orthodontics is the need of the hour, fuelled by the increasing number of adult patients seeking orthodontic treatment. Alternatives to labial appliance include clear aligners and lingual appliance. Conventional lingual treatment is laborious in terms of laboratory setup and manual dexterity of the operator, coupled with less than optimum treatment results. Customization of the appliance to meet varied requirements of each patient due to highly variable lingual morphology within and ...

  11. An Analysis of Correlation between Demand and Need for Orthodontic Treatment among Patients in Prince Sattam Bin Abdulaziz University Dental College Clinic, Kingdom of Saudi Arabia

    Science.gov (United States)

    Sam, George; Seehan, Saad; Al-Shayea, Meshari

    2015-01-01

    Background: The objective of the study is to determine whether there is any correlation between demand and need for orthodontic treatment among patients in Sattam Bin Abdulaziz University (SAU) Dental College Clinic. This study also provides a baseline data on the demand and need for orthodontic treatment among a Saudi population, which is important for planning public orthodontic dental services in the Kingdom. Materials and Methods: An epidemiological descriptive survey was conducted using two sets of questionnaire in the orthodontic clinic of Prince SAU, Al-Kharj among Saudi subjects with angle’s Class I, Class II, and Class III malocclusions, between the ages of 10 and 30 years for a period of 6 months with purposive sampling method. Results: Using Spearman’s rank correlation coefficient a significant correlation (0.482) was observed in male and female patients respectively with orthodontic demand (2) and treatment need (1) at 0.05 level of significance. A significant correlation (0.326) was observed for the study subjects (both males and females) with orthodontic demand (4) and treatment need (1) at 0.05 level of significance. A significant correlation (0.325) was observed in male patients with orthodontic demand (4) and treatment need (5) at 0.05 level of significance. Conclusions: Patients with the higher orthodontic demand required high treatment needs and vice versa.

  12. Patients’ acceptance of corticotomy-assisted orthodontics

    Science.gov (United States)

    Zawawi, Khalid H

    2015-01-01

    Objective To study patients’ acceptance of corticotomy-assisted orthodontics as a treatment option. Methods Adult patients seeking orthodontic treatment were asked to complete two sets of questionnaires; the first set included questions about age, sex, and level of education and general questions about orthodontic treatment; and the second set was related to the corticotomy-assisted orthodontics. Before answering the corticotomy questions, a brief description of the clinical procedure was explained and photographs of an actual procedure were shown. Results A total of 150 subjects were approached and 129 (86%) agreed to answer the questionnaires (72 male and 57 female patients). Of these, only 3.1% did hear about corticotomy and 7.8% selected corticotomy instead of extraction. Fear from the surgery (53.2%) was the most frequent reason for not selecting corticotomy followed by fear from pain (36.9%). The acceptance of corticotomy between males and females was similar. No relationship was found between the level of education and prior knowledge of the procedure, P=0.857. Prior knowledge about corticotomy was not a factor in selecting it as a treatment option (P=0.556) to reduce the treatment time (P=0.427). Conclusion The acceptance of corticotomy-assisted orthodontics as a treatment option was low. Fear from the surgery was the main reason for not selecting it. The acceptance of corticotomy-assisted orthodontics was not related to patient’s level of education or sex. PMID:26316719

  13. Effect of intrusive and retraction forces in labial and lingual orthodontics: A finite element study

    Directory of Open Access Journals (Sweden)

    Rohan Mascarenhas

    2014-01-01

    Full Text Available Objectives: Lingual orthodontics differs in biomechanics as compared to labial system and has biomechanical advantages. Although theoretical approaches have explained the differences between labial and lingual orthodontics, the finite element method (FEM may be better suited to analyze these differences. This study analyzes the effect of vertical and horizontal forces together on the tooth using FEM. Materials and Methods: An extracted right maxillary central incisor was radiographed and was used to create a solid model using ANSYS. The geometric model was converted into a finite element model with the help of ANSYS software. The model consists of 27,000 elements and 30,000 nodes. Two force vectors (vertical and horizontal were applied labially and lingually at 3 different heights- 4 mm, 5 mm and 6 mm from the incisal edge. Results: In the labial system, the net force vector passes through the center of resistance (CR and brings about intrusion. The net force vector in lingual orthodontics does not pass through the center of resistance and produces lingual tipping of the incisors. Conclusion: Intrusion and retraction forces bring about tipping of incisors in lingual orthodontics. The same amount of intrusion and retraction forces brings about intrusion of incisors in labial orthodontics. Therefore, direction and amount of forces should be carefully and judiciously applied after taking into consideration the resultant biomechanical differences.

  14. Orthodontic movement in deciduous teeth

    Scientific Electronic Library Online (English)

    Alberto, Consolaro.

    2015-04-01

    Full Text Available O dente decíduo é esfoliado graças à apoptose em seus cementoblastos, que desnuda a parte mineralizada da raiz e atrai os clastos. A rizólise é lenta, pois faltam mediadores em quantidade para acelerar o processo, mas ela se acelera e unidireciona quando se aproxima um folículo pericoronário de dent [...] e permanente rico em EGF e outros mediadores da reabsorção óssea - os responsáveis pelas reabsorções óssea na erupção e dentária decídua na rizólise e esfoliação. Se houver movimentação ortodôntica ou ancoragem em dentes decíduos, aumenta-se, também, o nível local desses mesmos mediadores, devendo-se estar bem consciente de que haverá uma aceleração da rizólise e, em decorrência, uma antecipação de sua esfoliação. No planejamento de casos em que dentes decíduos estejam envolvidos na movimentação ortodôntica e/ou ancoragem, deve-se ponderar: o benefício clínico para o paciente será relevante, a ponto de valer o risco de uma rizólise abreviada e inconveniente? Abstract in english Deciduous teeth exfoliate as a result of apoptosis induced by cementoblasts, a process that reveals the mineralized portion of the root while attracting clasts. Root resorption in deciduous teeth is slow due to lack of mediators necessary to speed it up; however, it accelerates and spreads in one si [...] ngle direction whenever a permanent tooth pericoronal follicle, rich in epithelial growth factor (EGF), or other bone resorption mediators come near. The latter are responsible for bone resorption during eruption, and deciduous teeth root resorption and exfoliation. Should deciduous teeth be subjected to orthodontic movement or anchorage, mediators local levels will increase. Thus, one should be fully aware that root resorption in deciduous teeth will speed up and exfoliation will early occur. Treatment planning involving deciduous teeth orthodontic movement and/or anchorage should consider: Are clinical benefits relevant enough as to be worth the risk of undergoing early inconvenient root resorption?

  15. Finite element-based force/moment-driven simulation of orthodontic tooth movement.

    Science.gov (United States)

    Geiger, M

    2013-01-01

    The objectives of this study were to develop a numerically controlled experimental set-up to predict the movement caused by the force systems of orthodontic devices and to experimentally verify this system. The presented experimental set-up incorporated an artificial tooth fixed via a 3D force/moment sensor to a parallel kinematics robot. An algorithm determining the initial movement of the tooth in its elastic embedding controlled the set-up. The initial tooth movement was described by constant compliances. The constants were obtained prior to the experiment in a parameterised finite element (FE) study on the basis of a validated FE model of a human molar. The long-term tooth movement was assembled by adding up a multiple of incremental steps of initial tooth movements. A pure translational movement of the tooth of about 8 mm resulted for a moment to force ratio of - 8.85 mm, corresponding to the distance between the bracket and the centre of resistance. The correct behaviour of this linear elastic model in its symmetry plane allows for simulating single tooth movement induced by orthodontic devices. PMID:22292517

  16. Influence of anatomical barriers on maxillary incisor root resorption after orthodontic treatment with premolar extractions

    Scientific Electronic Library Online (English)

    Antonio Geraldo de, Oliveira; Fabiana Guilhermina Ferreira, Castro.

    2012-04-01

    Full Text Available INTRODUCTION: Apical root resorption is a frequent and occasionally critical problem in orthodontic patients undergoing induced tooth movement. One of the factors that might influence prognosis, especially in maxillary incisors, which most frequently present resorptions, are the so-called the anatom [...] ical barriers; that is, proximity of the buccal and palatal cortical bones to the maxillary incisor roots. OBJECTIVE: The purpose of this research was to investigate whether patients with excessive vertical growth really present a small distance between the alveolar cortical bones and the maxillary incisor roots, and whether there is a correlation between this distance and the root resorption index in comparison with patients presenting horizontal growth. METHODS: The sample comprised orthodontic records of 18 patients with extraction planning of first maxillary premolars and treatment by the standard and/or preadjusted edgewise brackets. Their initial and final periapical radiographs were evaluated to determine the amount of root resorption that occurred. RESULTS: On the palatal side, patients with excessive vertical growth (Group 2 - SN-GoGn > 43º) showed a narrower alveolar bone than the horizontal growth patients (Group 1 - SN-GoGn

  17. Influence of anatomical barriers on maxillary incisor root resorption after orthodontic treatment with premolar extractions

    Directory of Open Access Journals (Sweden)

    Antonio Geraldo de Oliveira

    2012-04-01

    Full Text Available INTRODUCTION: Apical root resorption is a frequent and occasionally critical problem in orthodontic patients undergoing induced tooth movement. One of the factors that might influence prognosis, especially in maxillary incisors, which most frequently present resorptions, are the so-called the anatomical barriers; that is, proximity of the buccal and palatal cortical bones to the maxillary incisor roots. OBJECTIVE: The purpose of this research was to investigate whether patients with excessive vertical growth really present a small distance between the alveolar cortical bones and the maxillary incisor roots, and whether there is a correlation between this distance and the root resorption index in comparison with patients presenting horizontal growth. METHODS: The sample comprised orthodontic records of 18 patients with extraction planning of first maxillary premolars and treatment by the standard and/or preadjusted edgewise brackets. Their initial and final periapical radiographs were evaluated to determine the amount of root resorption that occurred. RESULTS: On the palatal side, patients with excessive vertical growth (Group 2 - SN-GoGn > 43º showed a narrower alveolar bone than the horizontal growth patients (Group 1 - SN-GoGn < 29º. However, the distance between the buccal cortical bone and the central incisor root apex showed no significant difference between Groups 1 and 2; CONCLUSIONS: It was concluded that there are no correlations between the proximity of buccal cortical bone, maxillary incisor roots and the root resorption index.

  18. Risk factors for low molar bite force in adult orthodontic patients.

    Science.gov (United States)

    Andersen, Malene Krogh; Sonnesen, Liselotte

    2013-08-01

    The aim was to analyse which parameters in a standard orthodontic material are most important for identifying factors for low bite force. Such analyses have not previously been reported in adult orthodontic patients. The sample comprised 95 adults (67 females and 28 males) aged 18-55 years sequentially admitted for conventional orthodontic treatment. All subjects had moderate to severe malocclusions. Bite force was measured by a pressure transducer, craniofacial dimensions and head posture were measured on profile radiographs, number of teeth in contact were evaluated with a plastic strip in intercuspidal position, and symptoms and signs of temporomandibular disorders (TMD) were evaluated by TMD screening. Associations were assessed by Spearman correlations, Wilcoxon signed-rank sum test, and multiple stepwise regression analyses. Associations were found between bite force and craniofacial dimensions as mandibular prognathia (S-N-Pg, P anchorage during treatment. PMID:22291432

  19. Genotoxic effects of banding procedure with different orthodontic cements on human oral mucosa cells

    OpenAIRE

    ÖZTÜRK, Fırat; Yüksel, Şengül; Toy, Ebubekir; KURTOĞLU, Elçin Latife; KÜÇÜK, Eyüp Burak

    2011-01-01

    To assess the genotoxic and cytotoxic effects of banding procedure with 5 different orthodontic cements on human oral buccal epithelium cells. Materials and methods: Fifty healthy volunteers (mean age: 14.54 ± 2.37 years) were randomly divided into 5 groups of 10. Preformed stainless steel molar bands (3M Unitek) were cemented to the upper and lower first molar teeth with 5 different orthodontic cements (Durelon, GC Fuji Ortho Band LC Paste Pak, Meron, Ultra Band Lok, and 3M Unitek Multi Cur...

  20. Structural integrity assessment of HANARO in-chimney bracket structures

    Energy Technology Data Exchange (ETDEWEB)

    Ryu, Jeong Soo; Lee, J. H.; Cho, Y. G.; Lee, J. H. [Korea Atomic Energy Research Institute, Taejon (Korea)

    1999-09-01

    In HANARO are there provided three hexagonal irradiation holes (CT, IR1 and IR2) in the central region of the core while four circular irradiation holes (OR3 {approx} OR6) in the outer core. There exist two types of irradiation facilities: uninstrumented or instrumented. The uninstrumented irradiation facility is little influenced by the coolant flow. But the dynamic behavior by the flow-induced vibration (FIV) and seismic loads is expected to largely occur in case of the instrumented test facility due to the long guide tube to protect the instrumentation cables. To suppress this dynamic behavior, the in-chimney bracket was designed. It is believed that the irradiation test can be successfully conducted since this bracket can reduce the FIV and dynamic response to seismic load as well. The installation position of the bracket is 60 cm below from the top of the chimney, i.e., thermosiphoning opening position. For evaluating the structural integrity on the in-chimney bracket and related reactor structures, ANSYS finite element analysis model is developed and the dynamic characteristics are analyzed. The seismic response analyses of in-chimney bracket and related reactor structures of HANARO under the design earthquake response spectrum loads of OBE(0.1g) and SSE(0.2g) are performed. The analysis result shows that the stress values in main points of reactor structures and in-chimney bracket for the seismic loads are also within the SAME Code limits. Therefore any damage on structural integrity is not expected when an in-chimney bracket is installed in the upper part of the reactor chimney. 12 refs., 32 figs., 21 tabs. (Author)

  1. Comparison of clinical bracket point registration with 3D laser scanner and coordinate measuring machine

    Scientific Electronic Library Online (English)

    Mahtab, Nouri; Arash, Farzan; Ali Reza Akbarzadeh, Baghban; Reza, Massudi.

    2015-02-01

    Full Text Available OBJETIVO: o objetivo do presente estudo foi avaliar o valor diagnóstico de um scanner a laser desenvolvido para determinar as coordenadas dos pontos de colagem de braquetes, comparando seus resultados aos resultados obtidos com uma máquina de medição coordenada (MMC). MÉTODOS: esse estudo experimen [...] tal diagnóstico foi conduzido com modelos ortodônticos obtidos a partir da arcada superior de 18 pacientes adultos, com oclusão normal de Classe I. Inicialmente, as coordenadas dos pontos de colagem de braquetes de todos os modelos foram mensuradas por uma MMC. Em seguida, as coordenadas tridimensionais (X, Y, Z) dos pontos foram mensuradas nos mesmos modelos por um scanner a laser 3D, desenvolvido na Universidade de Shahid Beheshti. A eficácia e confiabilidade dos dois sistemas foram avaliadas pelo Coeficiente de Correlação Intraclasse (CCI) e pela fórmula de Dahlberg. RESULTADOS: a diferença entre a média da dimensão mensurada pela MMC e o valor real obtido foi de 0,0066mm (IC 95%: 69,98340 - 69,99140). A diferença média para o scanner a laser foi de 0,107 ± 0,133 (95% IC: -0,002 - 0,24). Em cada método, as diferenças não foram significativas. Ao comparar os dois métodos, o CCI gerou um valor de 0,998 para a coordenada X e de 0,996 para a coordenada Y. A diferença média para as coordenadas registradas em cada dente da arcada foi de 0,616mm. CONCLUSÃO: a precisão das coordenadas do ponto de colagem dos braquetes foi a mesma no scanner a laser e na MMC. A diferença média entre as medições manteve-se dentro dos limites de erros operacionais. Abstract in english OBJECTIVE: The aim of the present study was to assess the diagnostic value of a laser scanner developed to determine the coordinates of clinical bracket points and to compare with the results of a coordinate measuring machine (CMM). METHODS: This diagnostic experimental study was conducted on maxil [...] lary and mandibular orthodontic study casts of 18 adults with normal Class I occlusion. First, the coordinates of the bracket points were measured on all casts by a CMM. Then, the three-dimensional coordinates (X, Y, Z) of the bracket points were measured on the same casts by a 3D laser scanner designed at Shahid Beheshti University, Tehran, Iran. The validity and reliability of each system were assessed by means of intraclass correlation coefficient (ICC) and Dahlberg's formula. RESULTS: The difference between the mean dimension and the actual value for the CMM was 0.0066 mm. (95% CI: 69.98340, 69.99140). The mean difference for the laser scanner was 0.107 ± 0.133 mm (95% CI: -0.002, 0.24). In each method, differences were not significant. The ICC comparing the two methods was 0.998 for the X coordinate, and 0.996 for the Y coordinate; the mean difference for coordinates recorded in the entire arch and for each tooth was 0.616 mm. CONCLUSION: The accuracy of clinical bracket point coordinates measured by the laser scanner was equal to that of CMM. The mean difference in measurements was within the range of operator errors.

  2. Comparative shear bond strength of some orthodontic bonding resins to enamel.

    Science.gov (United States)

    Trimpeneers, L M; Verbeeck, R M; Dermaut, L R; Moors, M G

    1996-02-01

    The aim of this study was to compare the in vitro bond strength, to bovine enamel measured in shear, of the orthodontic adhesives Lee Insta-bond (LiB), Rely-a-Bond (RaB), Right-on (Ro), Concise precoating method (Cc), Concise mixed method (CaB), Super-C (Sc), and Orthon (Or), and of the glass ionomer cement Ketac-Cem (KC). The fracture surfaces after debonding were also examined in order to determine the sites of failure. The results indicate that there is a significant difference between the shear bond strength obtained with the different adhesives so that the mean shear bond strength decreases in the order [Ro approximately Cab approximately Sc] > [LiB approximately RaB approximately Cc] > Or > KC. Moreover, for Cab and Sc it was found that the shear bond strength varies depending on the location on the bovine tooth. The failure site was essentially at the resin-bracket interface, except for Concise, where only 50 per cent of the cases failed at the resin-bracket interface. PMID:8746181

  3. Shear bond strength and antibacterial effects of orthodontic composite containing TiO2 nanoparticles.

    Science.gov (United States)

    Poosti, Maryam; Ramazanzadeh, Baratali; Zebarjad, Mojtaba; Javadzadeh, Parisa; Naderinasab, Mahboubeh; Shakeri, Mohammad T

    2013-10-01

    Nanofillers can reduce enamel demineralization without compromising physical properties of the composite. The aim of this study was to evaluate shear bond strength (SBS) and antibacterial effects of an orthodontic composite after adding titanium oxide (TiO2) nanoparticles. Light cure orthodontic composite paste (Transbond XT) was blended with TiO2 nanoparticles. A total of 30 extracted premolars were randomly allocated into two groups of 15. In order to bond brackets, Transbond XT adhesive and nanocomposite were used in each group, respectively. SBS of two groups were determined, and the adhesive remnant index (ARI) scores were assessed. A total of 45 composite discs specimen were prepared. Of the 45 discs, 30 discs were made from nanocomposite and tested for antibacterial properties immediately and 30 days after curing by direct contact test. The antibacterial properties of the remaining 15 discs that were made from the conventional composite were tested immediately after curing as control group. Student's t-test and chi-square tests were used to analyse the data with the significance level of 0.05. No significant difference was found between SBS of conventional and nanocomposites, 24 hours after curing (P = 0.58). Chi-square test showed that ARI scores of two groups were not significantly different after debonding (P = 0.69). Comparison of antibacterial effects between conventional and nanocomposite demonstrated significant difference between two groups, with nanocomposites having a higher antibacterial activity (P = 0.03). Colony count revealed no significant difference in bacterial growth immediately and 30 days after curing in nanocomposite group. Adding TiO2 nanoparticles to orthodontic composite enhances its antibacterial effects without compromising the SBS. PMID:23264617

  4. Tensile properties of orthodontic elastomeric ligatures

    Directory of Open Access Journals (Sweden)

    Ahrari F

    2010-01-01

    Full Text Available Context: Tensile properties of elastomeric ligatures become important when efficiency of orthodontic appliances is considered. Aims: The aim of this study was to compare tensile strength, extension to tensile strength, toughness and modulus of elasticity of elastomeric ligatures in both the as-received condition and after 28 days of immersion in the simulated oral environment. Furthermore, the changes that occurred in tensile properties of each brand of ligatures after 28 days were evaluated. Setting and Design : Experimental-laboratory based. Materials and Methods: Elastomeric ligatures were obtained from different companies and their tensile properties were measured using Zwick testing machine in both the as-received condition and after 28 days of immersion in the simulated oral environment. Statistical Analysis Used: The data were analyzed using independent sample t-tests, analysis of variance and Tukey tests. Results: After 28 days, all the ligatures experienced a significant decrease in tensile strength, extension to tensile strength and toughness ( P < 0.05, whereas modulus of elasticity increased in some groups and decreased in others. There were significant differences in tensile properties of different brands of ligatures in both conditions ( P < 0.05, with the exception of modulus of elasticity after 28 days. Conclusions : The decrease in strength properties of elastomeric ligatures shows that they should be replaced at each appointment to reduce the risk of rupture. There are significant differences in tensile properties of different brands of ligatures, which should be considered during selection of these products.

  5. Prosthetic and orthodontic rehabilitation of a patient with missing maxillary lateral incisors: a case report.

    Science.gov (United States)

    Gür, Emel; Aykent, Filiz; Gelgör, Ibrahim Erhan

    2007-01-01

    IPS Empress 2 materials can be used for fabrication of short-span fixed partial dentures in the anterior region as well as single crowns. This clinical report describes the prosthodontic treatment of a 16-year-old male patient with missing permanent maxillary left and right incisors with IPS Empress 2 fixed partial dentures following orthodontic treatment. PMID:17508075

  6. Avaliação do coeficiente de atrito de braquetes metálicos e estéticos com fios de aço inoxidável e beta-titânio / Evaluation of the friction coefficient of metal and esthetic brackets with stainless steel and beta-titanium wires

    Scientific Electronic Library Online (English)

    Cristine Pritsch, Braga; Guilherme Drumond, Vanzin; Ernani Menezes, Marchioro; João Carlos P., Beck.

    2004-12-01

    Full Text Available Um fator importante que define a eficácia dos aparelhos ortodônticos fixos é o atrito existente entre as superfícies de fios e braquetes. Assim, este estudo teve como objetivo investigar o coeficiente de atrito estático entre fios de aço inoxidável e beta-titânio (TP Orthodontics) e braquetes de aço [...] inoxidável (Dynalock® - Unitek), braquetes estéticos com slot de aço inoxidável (Clarity® - Unitek) e estéticos convencionais (Allure® - GAC). Para tanto, construiu-se um equipamento no Departamento de Engenharia Mecânica e Mecatrônica da PUCRS. Antes de serem iniciados os testes, foi quantificado o erro de método e constatou-se que não houve interferência significante (p>0,05) do fator operador nas medições. Então, pôde-se calcular o valor do coeficiente de atrito, obtido pela divisão da força de atrito pela carga normal. O método estatístico utilizado neste estudo foi Análise de Variância (ANOVA) e teste de Comparações Múltiplas (Tukey). Constatou-se que: 1) a combinação com menor coeficiente de atrito foi composta pelo fio de aço inoxidável e braquete Dynalock® e a que apresentou maior coeficiente foi a do braquete Allure® com o fio de beta-titânio; 2) o fio de beta-titânio apresentou coeficiente de atrito significativamente maior do que o fio de aço inoxidável; 3) o braquete Dynalock® não apresentou diferenças significativas em relação ao coeficiente de atrito do braquete Clarity® quando o fio utilizado foi de beta-titânio. No entanto, quando o fio testado foi de aço inoxidável, apresentou coeficiente de atrito significativamente menor. O braquete Clarity® apresentou coeficiente de atrito significativamente menor do que o braquete Allure®. Abstract in english An important factor that defines the effectiveness of the appliances is the friction between the surfaces of wires and brackets. Thus, that study was developed in order to investigate the static friction coefficient between stainless steel and beta-titanium wires (TP Orthodontics) and the stainless [...] steel brackets (Dynalock® - Unitek), esthetic brackets with a stainless steel slot (Clarity® - Unitek) and conventional esthetic brackets (Allure® - GAC). For this purpose, an equipment was built in the Department of Mechanical Engineering and Mechatronics at PUCRS. It should be stressed that before the tests began, the Method Error was quantified and it was found that there was no significant interference (p>0,05) by the factor operating in the measurements. From then, the friction coefficient could be calculated, obtained by dividing friction force by the normal load. The statistic method used in these study was Analysis of Variance (ANOVA) and Multiple Comparison test (Tukey). It was found that: 1) the combination with the lowest friction coefficient was constituted by the stainless steel wire against the Dynalock® bracket, and the one with the highest friction coefficient was that of the Allure® bracket with the beta-titanium wire; 2) the beta-titanium wire presented a friction coefficient that was significantly higher than the stainless steel wire; 3) the Dynalock® bracket did not present any significant differences in relation to the friction coefficient of the Clarity® bracket when the wire used was of beta-titanium. However, when the wire tested was of stainless steel, the Dynalock® bracket presented a significantly lower friction coefficient. The Clarity® bracket presented a significantly lower friction coefficient than the Allure® bracket.

  7. The in vivo orthodontic banding model for vital teeth and the in situ orthodontic banding model for hard-tissue slabs.

    Science.gov (United States)

    Ogaard, B; Rølla, G

    1992-04-01

    This paper presents the orthodontic banding model for vital teeth and the orthodontic in situ model for slabs of enamel, root surface, dentin, or other mineralized tissues such as shark enamel. The model for vital teeth is an in vivo model, since a crevice for plaque accumulation is created behind orthodontic bands on the buccal enamel surfaces of teeth in situ. Visible white-spot lesions are usually seen after a four-week banding period in the absence of fluoride. The microbiological flora developed behind the bands shows a similarity to that of natural caries. Microradiographic data show that the initial lesion is a softening of the enamel surface. Later, a subsurface lesion develops. A modification of the model has been developed for the use of slabs of mineralized tissues. In this model, slabs are mounted on a removable appliance. The slabs are covered with orthodontic banding material for plaque accumulation. Lesion development in enamel in the two model systems is almost identical. The benefit of the in vivo model is that caries development can be studied on vital teeth in young individuals. The model is independent of the patient's cooperation. No special diet is required, e.g., no sucrose rinsing. In the in situ model, slabs could be examined after one study period and then replaced for another period. PMID:1592969

  8. Evaluation of ionic degradation and slot corrosion of metallic brackets by the action of different dentifrices

    Scientific Electronic Library Online (English)

    Gustavo Antônio Martins, Brandão; Rafael Menezes, Simas; Leandro Moreira de, Almeida; Juliana Melo da, Silva; Marcelo de Castro, Meneghim; Antonio Carlos, Pereira; Haroldo Amorim de, Almeida; Ana Maria Martins, Brandão.

    2013-02-01

    Full Text Available OBJETIVO: avaliar in vitro a degradação iônica e corrosão do fundo do slot de braquetes metálicos submetidos à escovação com dentifrícios, realizando análises da composição química por Espectroscopia de Energia Dispersiva (EDS) e qualitativa por Microscopia Eletrônica de Varredura (MEV). MÉTODOS: fo [...] ram selecionados 38 braquetes divididos aleatoriamente em quatro grupos experimentais (n = 7). Dois grupos (n = 5) funcionaram como controles positivo e negativo. Aparelhos ortodônticos simulados foram confeccionados com fios de aço inoxidável 0,019" x 0,025" e anéis elastoméricos. Os grupos foram divididos de acordo com o tratamento de superfície: G1 (Máxima Proteção Anticáries®); G2 (Total 12®); G3 (Sensitive®); G4 (Branqueador®); Controle Positivo (saliva artificial) e Controle Negativo (sem tratamento). Foram realizados 28 ciclos de escovação e avaliações antes (T0) e após (T1) o experimento. RESULTADOS: o teste de Wilcoxon indicou não existir diferença nas concentrações iônicas de titânio (Ti), cromo (Cr), ferro (Fe) e níquel (Ni) entre os grupos. O grupo G2 apresentou redução significativa (p Abstract in english OBJECTIVE: To evaluate the in vitro ionic degradation and slot base corrosion of metallic brackets subjected to brushing with dentifrices, through analysis of chemical composition by Energy Dispersive Spectroscopy (EDS) and qualitative analysis by Scanning Electron Microscopy (SEM). METHODS: Thirty [...] eight brackets were selected and randomly divided into four experimental groups (n = 7). Two groups (n = 5) worked as positive and negative controls. Simulated orthodontic braces were assembled using 0.019 x 0.025-in stainless steel wires and elastomeric rings. The groups were divided according to surface treatment: G1 (Máxima Proteção Anticáries®); G2 (Total 12®); G3 (Sensitive®); G4 (Branqueador®); Positive control (artificial saliva) and Negative control (no treatment). Twenty eight brushing cycles were performed and evaluations were made before (T0) and after (T1) experiment. RESULTS: The Wilcoxon test showed no difference in ionic concentrations of titanium (Ti), chromium (Cr), iron (Fe) and nickel (Ni) between groups. G2 presented significant reduction (p

  9. Effect of adhesive remnant removal on enamel topography after bracket debonding

    Scientific Electronic Library Online (English)

    Larissa Adrian Meira, Cardoso; Heloísa Cristina, Valdrighi; Mario, Vedovello Filho; Américo Bortolazzo, Correr.

    2014-12-01

    Full Text Available INTRODUÇÃO: na finalização do tratamento ortodôntico, torna-se relevante o conhecimento da ação dos métodos de remoção do remanescente resinoso sobre o esmalte. OBJETIVO: o objetivo do estudo foi avaliar o efei [...] to de métodos de remoção do remanescente de resina após a descolagem do braquete e do polimento na rugosidade (Ra) e topografia (ESI) do esmalte. MÉTODOS: foram selecionados 50 pré-molares humanos, divididos em cinco grupos, de acordo com o método empregado para a remoção da resina residual: broca carbide tungstênio em alta rotação (BCT), discos Sof-Lex (SL), alicate removedor de resina (AL), ultrassom (US) e pontas Fiberglass (PF). Braquetes metálicos foram colados com Transbond XT, armazenados a 37° por 24 horas antes da descolagem com alicate removedor de braquete, sendo aplicados posteriormente os meios de remoção e executado o polimento com pasta de pedra-pomes. Realizou-se análises qualiquantitativas, com avaliações antes da colagem dos braquetes, após a descolagem e após o polimento, sendo os valores obtidos submetidos à análise estatística com teste F (ANOVA), de Tukey (Ra) e testes de Kruskal-Wallis e Bonferroni (ESI) (p Abstract in english INTRODUCTION: At orthodontic treatment completion, knowledge about the effects of adhesive remnant removal on enamel is paramount. OBJECTIVE: This study aimed at assessing the effect of different adhesive remna [...] nt removal methods on enamel topography (ESI) and surface roughness (Ra) after bracket debonding and polishing. METHODS: A total of 50 human premolars were selected and divided into five groups according to the method used for adhesive remnant removal: high speed tungsten carbide bur (TCB), Sof-Lex discs (SL), adhesive removing plier (PL), ultrasound (US) and Fiberglass burs (FB). Metal brackets were bonded with Transbond XT, stored at 37oC for 24 hours before debonding with adhesive removing plier. Subsequently, removal methods were carried out followed by polishing with pumice paste. Qualitative and quantitative analyses were conducted with pre-bonding, post-debonding and post-polishing analyses. Results were submitted to statistical analysis with F test (ANOVA) and Tukey's (Ra) as well as with Kruskal-Wallis and Bonferroni tests (ESI) (P

  10. Evaluation of ionic degradation and slot corrosion of metallic brackets by the action of different dentifrices

    Directory of Open Access Journals (Sweden)

    Gustavo Antônio Martins Brandão

    2013-02-01

    Full Text Available OBJECTIVE: To evaluate the in vitro ionic degradation and slot base corrosion of metallic brackets subjected to brushing with dentifrices, through analysis of chemical composition by Energy Dispersive Spectroscopy (EDS and qualitative analysis by Scanning Electron Microscopy (SEM. METHODS: Thirty eight brackets were selected and randomly divided into four experimental groups (n = 7. Two groups (n = 5 worked as positive and negative controls. Simulated orthodontic braces were assembled using 0.019 x 0.025-in stainless steel wires and elastomeric rings. The groups were divided according to surface treatment: G1 (Máxima Proteção Anticáries®; G2 (Total 12®; G3 (Sensitive®; G4 (Branqueador®; Positive control (artificial saliva and Negative control (no treatment. Twenty eight brushing cycles were performed and evaluations were made before (T0 and after (T1 experiment. RESULTS: The Wilcoxon test showed no difference in ionic concentrations of titanium (Ti, chromium (Cr, iron (Fe and nickel (Ni between groups. G2 presented significant reduction (p OBJETIVO: avaliar in vitro a degradação iônica e corrosão do fundo do slot de braquetes metálicos submetidos à escovação com dentifrícios, realizando análises da composição química por Espectroscopia de Energia Dispersiva (EDS e qualitativa por Microscopia Eletrônica de Varredura (MEV. MÉTODOS: foram selecionados 38 braquetes divididos aleatoriamente em quatro grupos experimentais (n = 7. Dois grupos (n = 5 funcionaram como controles positivo e negativo. Aparelhos ortodônticos simulados foram confeccionados com fios de aço inoxidável 0,019" x 0,025" e anéis elastoméricos. Os grupos foram divididos de acordo com o tratamento de superfície: G1 (Máxima Proteção Anticáries®; G2 (Total 12®; G3 (Sensitive®; G4 (Branqueador®; Controle Positivo (saliva artificial e Controle Negativo (sem tratamento. Foram realizados 28 ciclos de escovação e avaliações antes (T0 e após (T1 o experimento. RESULTADOS: o teste de Wilcoxon indicou não existir diferença nas concentrações iônicas de titânio (Ti, cromo (Cr, ferro (Fe e níquel (Ni entre os grupos. O grupo G2 apresentou redução significativa (p < 0,05 na concentração do íon alumínio (Al e os grupos G3 e G4 apresentaram aumento significativo (p < 0,05 nas concentrações do íon alumínio. A análise em MEV mostrou aumento nas características indicativas de corrosão dos grupos G2, G3 e G4. CONCLUSÃO: a análise por EDS revelou que os grupos controle e G1 não sofreram alterações na composição química. O grupo G2 apresentou degradação na quantidade de íons Al, e G3 e G4 sofreram aumento na concentração de Al. A imersão em saliva artificial e o dentifrício Máxima Proteção Anticáries® não alteraram o polimento de superfície. Os dentifrícios Total 12®, Sensitive® e Branqueador® alteraram o polimento de superfície.

  11. Centennial inventory: The changing face of orthodontics.

    Science.gov (United States)

    Ghafari, Joseph G

    2015-11-01

    The American Journal of Orthodontics and Dentofacial Orthopedics celebrates its centennial, safeguarded by the nearly 115-year-old American Association of Orthodontists. This journey witnessed the rise and demise of various developments, concepts, and procedures, while basic knowledge is still needed. Various periods can be defined in the past century, but the goals remain to obtain more accurate diagnosis through precise anatomic imaging, more controlled and faster tooth movement, more discreet appliances, and the balance of esthetics, function, and stability. The most recent technologic advances have buttressed these goals. Cone-beam computed tomography has brought 3-dimensional assessment to daily usage, albeit the original enthusiasm is tempered by the risk of additional radiation. Temporary anchorage devices or miniscrews have revolutionized orthodontic practice and loom as a solid cornerstone of orthodontic science. Decortication and microperforation promise to speed up tooth displacement by stimulating vascularization. The concept of the regional acceleratory phenomenon has touched upon even the timing of orthognathic surgery. The burden of esthetic appliances remains, with the demand for "cosmetic" appliances and clear aligners. Have these developments changed the face of orthodontics? Have we engaged in another turn wherein certain treatment modalities may fade, while others join mainstream applications? These questions are addressed in this essay on the challenges, promises, and limitations of current orthodontic technology, enhancement of biologic response, and personalized treatment approaches. PMID:26522032

  12. Shear bond strength of nanofilled flowable resins used for indirect bracket bonding

    Scientific Electronic Library Online (English)

    Carolina Ferreira Leite Moreira da, Silva; Marcelo Alves, Correa; Lourenço, Correr Sobrinho; Alexandre, Moro; Ricardo Cesar, Moresca; Gisele Maria, Correr.

    2012-12-01

    Full Text Available AIM: To evaluate the bond strength of brackets fixed with different materials (two light-cured nanofilled resins - Transbond Supreme LV and Flow Tain LV, a light-cured resin - Transbond XT (control) and two chemically cured resins for indirect bonding - Sondhi Rapid- Set and Custom I.Q.) using the i [...] ndirect bonding technique after 10 min and 24 h, and evaluate the type of failure. METHODS: One hundred premolars were selected and randomly divided into groups (n=10) according to the material and fixation period. The brackets were bonded through the indirect technique following the manufacturer's instructions and stored in deionized water at 37°C for 10 min or 24 h. After, the specimens were submitted to a shear bond strength (SBS) test (Instron) at 0.5 mm/min and evaluated for adhesive remnant index (ARI). The data were submitted to ANOVA and Tukey's test (p Sondhi Rapid-Set > Custom I.Q.). There was no significant difference in resistance values between 10 min and 24 h, regardless of the materials. Most groups showed adhesive remaining adhered to the enamel (scores 2 and 3) without statistically significant difference (p>0.05). CONCLUSIONS: It was concluded that the light-cured nanofilled materials used in indirect bonding showed greater resistance than the chemically cured materials. The period of fixation had no influence on the resistance for different materials.

  13. Basics of Ternary Algebras and their underlying Nambu Brackets

    International Nuclear Information System (INIS)

    Ternary algebras amount to closing systems of antisymmetrized trinomials of operators. The Filippov conditions (FI, which are not identities) for ternary algebras are contrasted to Bremner's identities dictated by associativity of operator products, and thus analogous to Jacobi identities. Maps of the known FI-compliant ternary algebras to underlying classical Nambu brackets are constructed, which then explain this compliance: FI-compliant ternary algebras are essentially classical Nambu brackets in disguise. In some cases involving infinite algebras, we show the classical limit may be obtained by a contraction of the quantal ternary algebra, and then explicitly realized through classical Nambu brackets. We illustrate this classical-contraction method on our Virasoro-Witt ternary algebra paradigm. The content of the talk is in the two references

  14. Which Factors Affect Dental Esthetics and Smile Attractiveness in Orthodontically Treated Patients?

    Directory of Open Access Journals (Sweden)

    Farzaneh Ahrari

    2016-01-01

    Full Text Available Objectives: This study aimed to find the factors that affect dental esthetics and smile attractiveness in orthodontically treated patients according to laypeople’s judgment, and to determine whether there is any relationship between dental and smile esthetics.Materials and Methods: Using the Q-sort technique, 60 laypersons (30 males, 30 females rated dental and smile photographs of 48 orthodontically treated patients based on their degree of attractiveness. Dental and smile parameters of each rated image were measured by Smile Analyzer software. The Student’s t-test and chi-square test were used to compare dental and smile parameters between attractive and unattractive images. The logistic regression was used to assess which variables predicted dental and smile esthetics in treated individuals.Results: The philtral to commissural height ratio and gingival display were significantly different in attractive and unattractive smiles (P=0.003 and P=0.02, respectively. None of the dental variables were found to be a determinant of dental esthetics at the end of the orthodontic treatment (P>0.05. According to the judgment of all raters (female and male and the male raters’ judgment, smile attractiveness could be predicted by philtral to commissural height ratio and buccal corridor ratio (P<0.05. There was no statistically significant relationship between dental esthetics and smile attractiveness in orthodontically treated patients (P>0.05.Conclusion: The philtral to commissural height ratio and buccal corridor ratio can be considered as predictors of smile attractiveness in orthodontically treated patients. Achieving dental esthetics at the end of orthodontic treatment does not guarantee smile attractiveness.

  15. Structural Analysis of the Redesigned Ice/Frost Ramp Bracket

    Science.gov (United States)

    Phillips, D. R.; Dawicke, D. S.; Gentz, S. J.; Roberts, P. W.; Raju, I. S.

    2007-01-01

    This paper describes the interim structural analysis of a redesigned Ice/Frost Ramp bracket for the Space Shuttle External Tank (ET). The proposed redesigned bracket consists of mounts for attachment to the ET wall, supports for the electronic/instrument cables and propellant repressurization lines that run along the ET, an upper plate, a lower plate, and complex bolted connections. The eight nominal bolted connections are considered critical in the summarized structural analysis. Each bolted connection contains a bolt, a nut, four washers, and a non-metallic spacer and block that are designed for thermal insulation. A three-dimensional (3D) finite element model of the bracket is developed using solid 10-node tetrahedral elements. The loading provided by the ET Project is used in the analysis. Because of the complexities associated with accurately modeling the bolted connections in the bracket, the analysis is performed using a global/local analysis procedure. The finite element analysis of the bracket identifies one of the eight bolted connections as having high stress concentrations. A local area of the bracket surrounding this bolted connection is extracted from the global model and used as a local model. Within the local model, the various components of the bolted connection are refined, and contact is introduced along the appropriate interfaces determined by the analysts. The deformations from the global model are applied as boundary conditions to the local model. The results from the global/local analysis show that while the stresses in the bolts are well within yield, the spacers fail due to compression. The primary objective of the interim structural analysis is to show concept viability for static thermal testing. The proposed design concept would undergo continued design optimization to address the identified analytical assumptions and concept shortcomings, assuming successful thermal testing.

  16. The 2/3 - convergence rate for the Poisson bracket

    OpenAIRE

    Buhovsky, Lev

    2008-01-01

    In this paper we introduce a new method for approaching the C^0 - rigidity results for the Poisson bracket. Using this method, we provide a different proof for the lower semi-continuity under C^0 perturbations, for the uniform norm of the Poisson bracket. We find the precise rate for the modulus of the semi-continuity. This extends the previous results of Cardin-Viterbo, Zapolsky, Entov and Polterovich. Using our method, we prove a C^0 - rigidity result in the spirit of the ...

  17. The 2/3 - convergence rate for the Poisson bracket

    CERN Document Server

    Buhovski, Lev

    2008-01-01

    We introduce a new method for approaching the C^0 rigidity results for the Poisson bracket. Using this method, we provide a different proof for the lower semi-continuity under C^0 perturbations, for the uniform norm of the Poisson bracket. We find the precise rate for the modulus of the semi-continuity. This extends the previous results of Cardin-Viterbo, Zapolsky, Entov and Polterovich. Using our method, we prove a C^0 rigidity result in the spirit of the work of Humiliere. We also discuss a general question of the C^0 rigidity for multilinear differential operators.

  18. Gyrokinetic energy conservation and Poisson-bracket formulation

    International Nuclear Information System (INIS)

    An integral expression for the gyrokinetic total energy of a magnetized plasma with general magnetic field configuration perturbed by fully electromagnetic fields was recently derived through the use of a gyro-center Lie transformation. We show that the gyrokinetic energy is conserved by the gyrokinetic Hamiltonian flow to all orders in perturbed fields. This paper is concerned with the explicit demonstration that a gyrokinetic Hamiltonian containing quadratic nonlinearities preserves the gyrokinetic energy up to third order. The Poisson-bracket formulation greatly facilitates this demonstration with the help of the Jacobi identity and other properties of the Poisson brackets. 18 refs

  19. Composição química e aspecto superficial do slot de braquetes metálicos Elemental composition and superficial aspect of metallic brackets slot

    Directory of Open Access Journals (Sweden)

    Tatiana Féres Assad-Loss

    2008-06-01

    Full Text Available OBJETIVO: avaliar a composição química e rugosidade do fundo do slot de 90 braquetes metálicos divididos em 9 grupos: grupo 1- aço inoxidável (Equilibrium 2 - Dentaurum; grupo 2 - titânio (Equilibrium ti - Dentaurum; grupo 3- cromo-cobalto (Topic- Dentaurum; grupo 4 - aço inoxidável (Standard -TP Orthodontics; grupo 5 - aço inoxidável (Serie light - American Orthodontics; grupo 6 - aço inoxidável (Kirium Line - Abzil Lancer; grupo 7 - aço inoxidável livre de níquel (Monobloc - Morelli; grupo 8 - aço inoxidável (Convencional- Morelli e grupo 9 - aço inoxidável livre de níquel (Monobloc Golden - Morelli. METODOLOGIA: a composição química foi analisada pela Espectroscopia de Energia Dispersiva. A avaliação qualitativa do fundo do slot foi realizada através do MEV classificada de 0 a 8, correspondente às características da superfície. RESULTADOS: composição química - grupo 1 = titânio puro; grupo 9 = recoberto por nitreto de titânio em 99,48%; grupo 3 = cromo-cobalto; grupo 8 = aço inoxidável livre de níquel. Os demais grupos são compostos de aço inoxidável. Avaliação da superfície - grupo 1 = valor 2 (superfície mais polida; grupos 2, 5 e 7 = valor 3 (aspecto de polimento; grupos 3, 8 e 9 = valor 6 (menor polimento; grupo 4 = valor 6,5 (maior rugosidade e o grupo 6 = valor 5 (características intermediárias de polimento. CONCLUSÕES: os braquetes metálicos são compostos de diferentes ligas e estão disponíveis com baixo conteúdo ou ausência de níquel. Os braquetes de titânio apresentaram polimento semelhante aos de aço inoxidável, porém os recobertos por nitreto de titânio e os de cromo-cobalto mostraram superfície mais irregular ou menos polida.AIM: To evaluate the elemental composition and the slot roughness of 90 metallic brackets divided into 9 groups: group 1 - stainless steel (Equilibrium 2 - Dentaurum; group 2 - titanium (Equilibrium ti - Dentaurum; group 3 - chromium-cobalt (Topic - Dentaurum; group 4 - stainless steel (Standard - TP Orthodontics; group 5 - stainless steel (Serie light - American Orthodontics; group 6 - stainless steel (Kirium Line - Abzil Lancer; group 7 - stainless steel (Monobloc - Morelli; group 8 - stainless steel (Standard - Morelli and group 9 - stainless steel (Monobloc Golden - Morelli. METHODS: Elemental composition was evaluated using the Spectroscopy of Dispersive Energy. The qualitative slot surface evaluation was assessed using a 500X scanning electron microscope. The microphotography was classified according to surface characteristics in 0-8 values. RESULTS: Elemental composition - group 1 = 100% titanium alloy; group 9 = 99,48% of titanium nitride coated. Group 3 = cobalt-chromium alloy; Group 8 = nickel free stainless steel alloy; other groups stainless steel alloy. Surface evaluation - Group 1 = value 2 (smoothest surface; Groups 2, 5 and 7 =value 3 (smooth surface; Groups 3, 8 and 9 showed value 6 (roughness surface; Group 4 = value 6,5 (the most roughness and irregular surface; and Group 6 has intermediate characteristics among the groups, with value 5. CONCLUSIONS: Metallic brackets were composed of different alloys and they were available with a small percentage or no nickel. The surface roughness was similar for both titanium and stainless steel, however the titanium nitride coated and cobalt-chromium showed an irregular and rough surface.

  20. Composição química e aspecto superficial do slot de braquetes metálicos / Elemental composition and superficial aspect of metallic brackets slot

    Scientific Electronic Library Online (English)

    Tatiana Féres, Assad-Loss; Regina Maria Lopes, Neves; José Nelson, Mucha.

    2008-06-01

    Full Text Available OBJETIVO: avaliar a composição química e rugosidade do fundo do slot de 90 braquetes metálicos divididos em 9 grupos: grupo 1- aço inoxidável (Equilibrium 2 - Dentaurum); grupo 2 - titânio (Equilibrium ti - Dentaurum); grupo 3- cromo-cobalto (Topic- Dentaurum); grupo 4 - aço inoxidável (Standard -TP [...] Orthodontics); grupo 5 - aço inoxidável (Serie light - American Orthodontics); grupo 6 - aço inoxidável (Kirium Line - Abzil Lancer); grupo 7 - aço inoxidável livre de níquel (Monobloc - Morelli); grupo 8 - aço inoxidável (Convencional- Morelli) e grupo 9 - aço inoxidável livre de níquel (Monobloc Golden - Morelli). METODOLOGIA: a composição química foi analisada pela Espectroscopia de Energia Dispersiva. A avaliação qualitativa do fundo do slot foi realizada através do MEV classificada de 0 a 8, correspondente às características da superfície. RESULTADOS: composição química - grupo 1 = titânio puro; grupo 9 = recoberto por nitreto de titânio em 99,48%; grupo 3 = cromo-cobalto; grupo 8 = aço inoxidável livre de níquel. Os demais grupos são compostos de aço inoxidável. Avaliação da superfície - grupo 1 = valor 2 (superfície mais polida); grupos 2, 5 e 7 = valor 3 (aspecto de polimento); grupos 3, 8 e 9 = valor 6 (menor polimento); grupo 4 = valor 6,5 (maior rugosidade) e o grupo 6 = valor 5 (características intermediárias de polimento). CONCLUSÕES: os braquetes metálicos são compostos de diferentes ligas e estão disponíveis com baixo conteúdo ou ausência de níquel. Os braquetes de titânio apresentaram polimento semelhante aos de aço inoxidável, porém os recobertos por nitreto de titânio e os de cromo-cobalto mostraram superfície mais irregular ou menos polida. Abstract in english AIM: To evaluate the elemental composition and the slot roughness of 90 metallic brackets divided into 9 groups: group 1 - stainless steel (Equilibrium 2 - Dentaurum); group 2 - titanium (Equilibrium ti - Dentaurum); group 3 - chromium-cobalt (Topic - Dentaurum); group 4 - stainless steel (Standard [...] - TP Orthodontics); group 5 - stainless steel (Serie light - American Orthodontics); group 6 - stainless steel (Kirium Line - Abzil Lancer); group 7 - stainless steel (Monobloc - Morelli); group 8 - stainless steel (Standard - Morelli) and group 9 - stainless steel (Monobloc Golden - Morelli). METHODS: Elemental composition was evaluated using the Spectroscopy of Dispersive Energy. The qualitative slot surface evaluation was assessed using a 500X scanning electron microscope. The microphotography was classified according to surface characteristics in 0-8 values. RESULTS: Elemental composition - group 1 = 100% titanium alloy; group 9 = 99,48% of titanium nitride coated. Group 3 = cobalt-chromium alloy; Group 8 = nickel free stainless steel alloy; other groups stainless steel alloy. Surface evaluation - Group 1 = value 2 (smoothest surface); Groups 2, 5 and 7 =value 3 (smooth surface); Groups 3, 8 and 9 showed value 6 (roughness surface); Group 4 = value 6,5 (the most roughness and irregular surface); and Group 6 has intermediate characteristics among the groups, with value 5. CONCLUSIONS: Metallic brackets were composed of different alloys and they were available with a small percentage or no nickel. The surface roughness was similar for both titanium and stainless steel, however the titanium nitride coated and cobalt-chromium showed an irregular and rough surface.

  1. Orthodontic anchorage: a systematic review.

    Science.gov (United States)

    Feldmann, Ingalill; Bondemark, L

    2006-05-01

    The aim of this systematic review was to examine, in an evidence-based way, what kind of orthodontic anchorage systems/applications are evaluated and their effectiveness. A literature survey from the Pub Med and Cochrane databases covering the period from January 1966 to December 2004 was performed. Randomized controlled trials (RCT), prospective and retrospective controlled studies, and clinical trials comparing at least two anchorage situations were included. Two reviewers selected and extracted the data independently and also assessed the quality of the retrieved studies. The search strategy resulted in 494 articles, of which 14 met the inclusion criteria. Two main anchorage situations were identified: anchorage of molars during space closure after premolar extractions and anchorage loss in the incisor or premolar region (or both) during molar distalization. Because of contradictory results and the vast heterogeneity in study methods, the scientific evidence was too weak to evaluate anchorage efficiency during space closure. Intraoral molar distalization leads to anchorage loss in various amounts depending on the choice of distalization unit. Most of the studies had serious problems with small sample size, confounding factors, lack of method error analysis, and no blinding in measurements. To obtain reliable scientific evidence, controlled RCT's with sufficient sample sizes are needed to determine which anchorage system is the most effective in the respective anchorage situation. Further studies should also consider patient acceptance and cost analysis as well as implants as anchorage. PMID:16637733

  2. Orthodontic and surgical management of a skeletal Class III case.

    Science.gov (United States)

    Ousehal, Lahcen; El Mabrak, Asmaa; Kadiri, Fatmi

    2015-12-01

    This article presents a case report on a skeletal Class III associated with transverse maxillary constriction treated using a combined orthodontic and surgical approach. The presurgical orthodontic phase involved decompensation for the malocclusion accompanied by upper arch expansion. After 15months of orthodontic preparation, the patient underwent mandibular setback surgery. A period of orthodontic stabilization and finishing was undertaken during the three months post-surgery, with final debonding 24months after the start of treatment. The esthetic and functional results were very satisfactory thanks to this collaboration between orthodontics and surgery. PMID:26507298

  3. Assessment of pain experience in adults and children after bracket bonding and initial archwire insertion

    Scientific Electronic Library Online (English)

    Marcio José da Silva, Campos; Marcelo Reis, Fraga; Nádia Rezende Barbosa, Raposo; Ana Paula, Ferreira; Robert Willer Farinazzo, Vitral.

    2013-10-01

    Full Text Available INTRODUÇÃO: durante o tratamento ortodôntico, os pacientes rotineiramente relatam situações de dor, que ocorrem em até 95% dos casos. Essa dor é proveniente de alterações no ligamento periodontal e nos tecidos moles circundantes, e a sua intensidade e prevalência variam de acordo com a faixa etária [...] dos pacientes. OBJETIVO: o objetivo desse estudo foi avaliar a experiência de dor nos dentes e na mucosa bucal em pacientes adultos e crianças durante duas fases iniciais do tratamento ortodôntico. MÉTODOS: a intensidade de dor nos dentes e na mucosa bucal relatada por 20 pacientes, 10 crianças (11-13 anos) e 10 adultos (18-37 anos), foi registrada com uma Escala Visual Analógica (EVA) durante 14 dias, sendo 7 dias apenas com os braquetes colados e 7 dias com o arco inicial inserido. RESULTADOS: não houve diferença significativa na intensidade de dor entre adultos e crianças. Após a colagem dos braquetes, 50% das crianças e 70% dos adultos relataram dor; e, após a inserção do arco inicial, a prevalência de relatos foi de 70% para ambos os grupos. Os adultos relataram dores constantes e de baixa intensidade na mucosa bucal, enquanto as crianças mostraram grande variação na intensidade, porém com tendência de diminuição durante o período de avaliação. Os picos de intensidade e prevalência de dor nos dentes ocorreram, respectivamente para crianças e adultos, 24h e 48h após a inserção do arco inicial. CONCLUSÃO: de modo geral, as crianças exibiram menor prevalência de relatos de dor, porém com maior intensidade do que os adultos. Abstract in english INTRODUCTION: Ninety five percent of orthodontic patients routinely report pain, due to alterations in the periodontal ligament and surrounding soft tissues, with intensity and prevalence varying according to age. OBJECTIVE: This study aimed to assess toothache and buccal mucosal pain in adults and [...] children during two initial phases of the orthodontic treatment. METHODS: The intensity of toothache and buccal mucosal pain reported by 20 patients, 10 children (11-13 years) and 10 adults (18-37 years) was recorded with the aid of a Visual Analog Scale (VAS), during 14 days - 7 days with bonded brackets only and 7 days with the initial archwire inserted. RESULTS: There was no significant difference in pain intensity among adults and children. After bracket bonding, 50% of the children and 70% of the adults reported pain. 70% of both groups reported pain after initial archwire insertion. While adults reported constant, low intensity, buccal mucosal pain, the children showed great variation of pain intensity, but with a trend towards decreasing pain during the assessment period. After initial archwire insertion the peaks of toothache intensity and prevalence occurred 24 hours in children and 48 hours in adults. CONCLUSIONS: In general, children reported pain less frequently than adults did, though with greater intensity.

  4. Protocol for absolute anchorage in orthodontics: miniscrew

    Directory of Open Access Journals (Sweden)

    Adriana Silva de Carvalho

    2008-01-01

    Full Text Available Anchorage is one of the most important points in orthodontic treatment. With the object of reducing the need for cooperation from patients, and enlarge the treatment possibilities, miniscrews have been used as aids in orthodontic treatment, providing the possibility of absolute anchorage. The purpose of this article was to present a clinical protocol in order to facilitate the planning and performance of miniscrew application. When installing miniscrews, there is the transmucous technique, in which perforation is performed directly in the mucosa using a bur, indicated for keratinized mucosa; and the flap technique, in which bone is exposed with the aid of a flap and perforation is made in the bone, indicated in alveolar mucosa. When well planned and performed, miniscrews provide very satisfactory results and are an excellent method of orthodontic anchorage.

  5. Orthodontic Micro-implant-absoanchor…An Overview

    Directory of Open Access Journals (Sweden)

    Anitha G

    2010-10-01

    Full Text Available Orthodontists have been straightening teeth for decades relying on the ancient physics principle "every action has a reaction," in which tooth displacement in one part of the jaw causes movement on the other as well. Use of dental implants as orthodontic anchors, however, is changing that principle by expediting treatment times and expanding possibilities for previously untreatable cases. In conventional orthodontics, teeth are used to move other teeth, but implants can serve as excellent anchors from which force is applied to move the targeted teeth without causing shifts in other teeth..Cases progress faster when implants are used as anchorage, but not because teeth are subject to higher force levels. Rather, it's is the result of a more efficient appliance design that provides the ability to move multiple teeth simultaneously rather than individually, as is necessary in conventional orthodontics.

  6. Adult orthodontics: multi- or interdisciplinary treatment approach

    DEFF Research Database (Denmark)

    Melsen, Birte

    2007-01-01

    An increasing number of adult patients seen in the orthodontic offices are presenting with an ongoing degeneration caused either by loss of one or more teeth and/or progressing periodontal disease. The treatment of these patients can rarely stand alone and both diagnosis and treatment planning...... conservative approach practiced in many places within periodontology, it should be appreciated that any orthodontic tooth movement involving intrusive components should not be performed in the presence of pathological pockets. New regenerative periodontal treatment procedures have improved the prognosis for...... experiments carried out on monkeys and dogs have repeatedly demonstrated that it is possible to regain lost attachment even in the case of horizontal bone loss through a carefully conducted combined periodontal- and orthodontic treatment and long-term follow-up have confirmed that the results can be...

  7. Ortodoncia y periodoncia Orthodontics and periontics

    Directory of Open Access Journals (Sweden)

    P. Tortolini

    2011-08-01

    Full Text Available El paciente periodontal se puede beneficiar con un tratamiento combinado de ortodoncia y periodoncia, ya que determinados movimientos dentarios como la extrusión, la intrusión, la rotación, el enderezamiento, etc pueden ser favorables para el periodonto enfermo. Lo que es fundamental antes de empezar el tratamiento de ortodoncia de un paciente periodontal es eliminar la inflamación activa de los tejidos.Periodontal patients can benefit from a combined treatment of orthodontics and periodontics, because certain tooth movements as extrusión, intrusion, rotation, straightening, etc. may be favorable for the periodontal patient. Which is essential before starting orthodontic treatment of a periodontal patient is to eliminate active inflammation of the tissues.

  8. Anxiety among adolescents and its affect on orthodontic compliance

    Directory of Open Access Journals (Sweden)

    Trakyali G

    2009-01-01

    Full Text Available Background: Investigations have suggested that poor compliance could be an indicator of poor relationship with family and could be related to the person?s personality traits. Aim: The aim of this study was to determine the effect of parents attitude, the anxiety during treatment and self-confidence/self-care of the patient on cooperation during orthodontic treatment. Materials and Methods: The study material consisted of questionnaires completed by 82 adolescent patients and their parents. The patients were divided into two groups of 42 compliant and 40 non-compliant patients. The above-mentioned questionnaries were State-Trait Anxiety Inventory-STAI, Piers-Harris Children?s Self Concept Scale and The Exercise of Self-Care Agency for the patients and Mc Master Family Assessment Device and Parental Attitude Research Instrument-PARI for the parents. Results: The problem solving and caring attitude of the father and his determinative role in the family had a positive infulence on the compliance of the child. The patients who showed better compliance also had a lower state of anxiety, which could also be explained by the positive effect of the attitude of the father in the family. Conclusion: It would be useful to overcome the increased state of anxiety of the child in the orthodontic clinic by using educational and relaxation techniques. Besides, it would be wise to ask the father to be present at the first appointment during part of the education of the child.

  9. Analysis of Bracket Assembly for Diversion Box Leak Detector

    International Nuclear Information System (INIS)

    This Supporting Document Presents Structural and Stress Analysis of a Bracket Assembly for the diversion box leak detectors related to the Cross Site Transfer Project. The results show that the assembly meets the requirements for dead load and natural phenomena hazards loads (seismic and wind)

  10. Weak Dirac bracket construction and the superparticle covariant quantization problem

    International Nuclear Information System (INIS)

    The general procedure for constructing a consistent covariant Dirac-type bracket for the models with mixed first and second class constraints is presented. The proposed scheme essentially relies upon explicit separation of the initial constraints into infinitely reducible first and second class ones (by making use of some covariant projectors). Reducibility of the second class constraints involved manifests itself in weakening some properties of the bracket as compared to the standard Dirac one. In particular, a commutation of any quantity with the second class constraints and the Jacobi identity holds on the second class constraint surface only. The procedure developed is realized for a N=1 Brink-Schwarz superparticle in arbitrary dimension and for a N=1, D=9 massive superparticle with the Wess-Zumino term. The possibility to apply the bracket for quantizing the superparticles within the framework of the recent unified algebra approach by I.A.Batalin and I.V.Tyutin (1992,1993) is examined. It is shown, in particular, that for a D=9 massive superparticle it is impossible to construct a Dirac-type bracket possessing a (strong) Jacobi identity in a full phase space. (orig.)

  11. Commutativity of missing label operators in terms of Berezin brackets

    Energy Technology Data Exchange (ETDEWEB)

    Boya, Luis J [Dpto. Fisica Teorica, Facultad de Ciencias, Universidad de Zaragoza, E-50009 Zaragoza (Spain); Campoamor-Stursberg, Rutwig [Dpto. GeometrIa y TopologIa, Fac. CC. Matematicas, Universidad Complutense de Madrid, Plaza de Ciencias, 3 E-28040 Madrid (Spain)], E-mail: luisjo@unizar.es, E-mail: rutwig@mat.ucm.es

    2009-06-12

    We obtain a criterion on the commutativity of polynomials in the enveloping algebra of a Lie algebra in terms of an involution condition with respect to the Berezin bracket. As an application, it is shown that the commutativity requirement of missing label operators for reduction chains in the missing label problem can be solved analytically.

  12. Seismic response Analyses of Hanaro in-chimney bracket structures

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jae Han; Ryu, J.S.; Cho, Y.G.; Lee, H.Y.; Kim, J.B

    1999-05-01

    The in-chimney bracket will be installed in the upper part of chimney, which holds the capsule extension pipes in upper one-third of length. For evaluating the effects on the capsules and related reactor structures, ANSYS finite element analysis model is developed and the dynamic characteristics are analyzed. The seismic response anlayses of in-chimney bracket and related reactor structures of HANARO under the design earthquake response spectrum loads of OBE (0.1 g) and SSE (0.2 g) are performed. The maximum horizontal displacements of the flow tubes are within the minimum half gaps between close flow tubes, it is expected that these displacement will not produce any contact between neighbor flow tubes. The stress values in main points of reactor structures and in-chimney bracket for the seismic loads are also within the ASME Code limits. It is also confirmed that the fatigue usage factor is muchless than 1.0. So, any damage on structural integrity is not expected when an in-chimney bracket is installed to upper part of the reactor chimney. (author). 12 refs., 24 tabs., 37 figs.

  13. U matrix construction for Quantum Chromodynamics through Dirac brackets

    International Nuclear Information System (INIS)

    A procedure for obtaining the U matrix using Dirac brackets, recently developed by Kiefer and Rothe, is applied for Quantum Chromodynamics. The correspondent interaction Lagrangian is the same obtained by Schwinger, Christ and Lee, using independent methods. (L.C.J.A.)

  14. Seismic response Analyses of Hanaro in-chimney bracket structures

    International Nuclear Information System (INIS)

    The in-chimney bracket will be installed in the upper part of chimney, which holds the capsule extension pipes in upper one-third of length. For evaluating the effects on the capsules and related reactor structures, ANSYS finite element analysis model is developed and the dynamic characteristics are analyzed. The seismic response anlayses of in-chimney bracket and related reactor structures of HANARO under the design earthquake response spectrum loads of OBE (0.1 g) and SSE (0.2 g) are performed. The maximum horizontal displacements of the flow tubes are within the minimum half gaps between close flow tubes, it is expected that these displacement will not produce any contact between neighbor flow tubes. The stress values in main points of reactor structures and in-chimney bracket for the seismic loads are also within the ASME Code limits. It is also confirmed that the fatigue usage factor is much less than 1.0. So, any damage on structural integrity is not expected when an in-chimney bracket is installed to upper part of the reactor chimney. (author). 12 refs., 24 tabs., 37 figs

  15. Heat treatment following surface silanization in rebonded tribochemical silica-coated ceramic brackets: shear bond strength analysis

    Science.gov (United States)

    SILVA, Emilia Adriane; TRINDADE, Flávia Zardo; RESKALLA, Hélcio Nagib José Feres; de QUEIROZ, José Renato Cavalcanti

    2013-01-01

    Objective This study aimed to evaluate the effects of heat treatment on the tribochemical silica coating and silane surface conditioning and the bond strength of rebonded alumina monocrystalline brackets. Material and Methods Sixty alumina monocrystalline brackets were randomly divided according to adhesive base surface treatments (n=20): Gc, no treatment (control); Gt, tribochemical silica coating + silane application; Gh, as per Gt + post-heat treatment (air flux at 100ºC for 60 s). Brackets were bonded to the enamel premolars surface with a light-polymerized resin and stored in distilled water at 37ºC for 100 days. Additionally, half the specimens of each group were thermocycled (6,000 cycles between 5-55ºC) (TC). The specimens were submitted to the shear bond strength (SBS) test using a universal testing machine (1 mm/min). Failure mode was assessed using optical and scanning electron microscopy (SEM), together with the surface roughness (Ra) of the resin cement in the bracket using interference microscopy (IM). 2-way ANOVA and the Tukey test were used to compare the data (p>0.05). Results The strategies used to treat the bracket surface had an effect on the SBS results (p=0.0), but thermocycling did not (p=0.6974). Considering the SBS results (MPa), Gh-TC and Gc showed the highest values (27.59±6.4 and 27.18±2.9) and Gt-TC showed the lowest (8.45±6.7). For the Ra parameter, ANOVA revealed that the aging method had an effect (p=0.0157) but the surface treatments did not (p=0.458). For the thermocycled and non-thermocycled groups, Ra (µm) was 0.69±0.16 and 1.12±0.52, respectively. The most frequent failure mode exhibited was mixed failure involving the enamel-resin-bracket interfaces. Conclusion Regardless of the aging method, Gh promoted similar SBS results to Gc, suggesting that rebonded ceramic brackets are a more effective strategy. PMID:24037072

  16. Heat treatment following surface silanization in rebonded tribochemical silica-coated ceramic brackets: shear bond strength analysis

    Directory of Open Access Journals (Sweden)

    Emilia Adriane Silva

    2013-07-01

    Full Text Available OBJECTIVE: This study aimed to evaluate the effects of heat treatment on the tribochemical silica coating and silane surface conditioning and the bond strength of rebonded alumina monocrystalline brackets. MATERIAL AND METHODS: Sixty alumina monocrystalline brackets were randomly divided according to adhesive base surface treatments (n=20: Gc, no treatment (control; Gt, tribochemical silica coating + silane application; Gh, as per Gt + post-heat treatment (air flux at 100ºC for 60 s. Brackets were bonded to the enamel premolars surface with a light-polymerized resin and stored in distilled water at 37ºC for 100 days. Additionally, half the specimens of each group were thermocycled (6,000 cycles between 5-55ºC (TC. The specimens were submitted to the shear bond strength (SBS test using a universal testing machine (1 mm/min. Failure mode was assessed using optical and scanning electron microscopy (SEM, together with the surface roughness (Ra of the resin cement in the bracket using interference microscopy (IM. 2-way ANOVA and the Tukey test were used to compare the data (p>0.05. RESULTS: The strategies used to treat the bracket surface had an effect on the SBS results (p=0.0, but thermocycling did not (p=0.6974. Considering the SBS results (MPa, Gh-TC and Gc showed the highest values (27.59±6.4 and 27.18±2.9 and Gt-TC showed the lowest (8.45±6.7. For the Ra parameter, ANOVA revealed that the aging method had an effect (p=0.0157 but the surface treatments did not (p=0.458. For the thermocycled and non-thermocycled groups, Ra (µm was 0.69±0.16 and 1.12±0.52, respectively. The most frequent failure mode exhibited was mixed failure involving the enamel-resin-bracket interfaces. CONCLUSION: Regardless of the aging method, Gh promoted similar SBS results to Gc, suggesting that rebonded ceramic brackets are a more effective strategy.

  17. The general harmonic-oscillator brackets: compact expression, symmetries, sums and Fortran code

    International Nuclear Information System (INIS)

    We present a very simple expression and a Fortran code for the fast and precise calculation of three-dimensional harmonic-oscillator transformation brackets. The complete system of symmetries for the brackets along with analytical expressions for sums containing products of two and three brackets is given

  18. The general harmonic-oscillator brackets: compact expression, symmetries, sums and Fortran code

    OpenAIRE

    Kamuntavicius, G. P.; Kalinauskas, R. K.; Barrett, B. R.; Mickevicius, S.; Germanas, D.

    2001-01-01

    We present a very simple expression and a Fortran code for the fast and precise calculation of three-dimensional harmonic-oscillator transformation brackets. The complete system of symmetries for the brackets along with analytical expressions for sums, containing products of two and three brackets, is given.

  19. Corrosion behavior of self-ligating and conventional metal brackets

    Scientific Electronic Library Online (English)

    Lúcio Henrique Esmeraldo Gurgel, Maia; Hibernon, Lopes Filho; Antônio Carlos de Oliveira, Ruellas; Mônica Tirre de Souza, Araújo; Delmo Santiago, Vaitsman.

    2014-04-01

    Full Text Available Objetivo: testar a hipótese nula de que o processo de envelhecimento em braquetes autoligáveis não é superior ao de braquetes convencionais. Métodos: Vinte e cinco braquetes metálicos convencionais (GN, 3M/Unitek; GE, GAC; VE, Aditek) e 25 autoligáveis (SCs, 3M/Unitek; INs, GAC; ECs, Aditek) d [...] e três fabricantes (n = 150) foram submetidos ao envelhecimento em solução de NaCl à temperatura constante de 37 ± 1ºC, durante 21 dias. O conteúdo de íons níquel, cromo e ferro na solução coletada com 7, 14 e 21 dias foi quantificado por meio de espectrofotometria de absorção atômica. Depois de completado o processo de envelhecimento, os braquetes foram analisados com microscópio eletrônico de varredura (MEV), em magnificações de 22x e de 1.000x. Resultados: comparando-se a liberação de metais por braquetes autoligáveis e convencionais do mesmo fabricante, observou-se que o grupo SCs liberou mais níquel (p Abstract in english Objective: To test the null hypothesis that the aging process in self-ligating brackets is not higher than in conventional brackets. Methods: Twenty-five conventional (GN-3M/Unitek; GE-GAC; VE-Aditek) and 25 self-ligating (SCs-3M/Unitek; INs-GAC; ECs-Aditek) metal brackets from three manufactu [...] rers (n = 150) were submitted to aging process in 0.9% NaCl solution at a constant temperature of 37 ± 1ºC for 21 days. The content of nickel, chromium and iron ions in the solution collected at intervals of 7, 14 and 21 days was quantified by atomic absorption spectrophotometry. After the aging process, the brackets were analyzed by scanning electron microscopy (SEM) under 22X and 1,000X magnifications. Results: Comparison of metal release in self-ligating and conventional brackets from the same manufacturer proved that the SCs group released more nickel (p

  20. Gingival esthetics: an orthodontic and periodontal approach

    OpenAIRE

    Máyra Reis Seixas; Roberto Amarante Costa-Pinto; Telma Martins de Araújo

    2012-01-01

    INTRODUCTION: Currently, people's esthetic requirements and expectations have increased substantially. Therefore, dentists have been seeking ways to provide excellent treatment results which, consequently, increasingly require a well organized transdisciplinary approach. The link between orthodontics and periodontics became evident from the moment professionals began to understand the biology of tooth movement. As regards smile esthetics, however, such cooperation is now essential. OBJECTIVE:...

  1. Neurologic Regulation and Orthodontic Tooth Movement.

    Science.gov (United States)

    Kyrkanides, Stephanos; Huang, Hechang; Faber, Richard D

    2016-01-01

    Pain and discomfort are prevalent symptoms among the vast majority of patients with fixed orthodontic appliances and is the most disliked aspect of treatment. The periodontium is a highly innervated structure that also provides the necessary trophic factors, such as nerve growth factor, which promote neuronal survival, maintenance and axonal growth, via interaction with specific nerve surface receptors, such as TrkA. Various types of nerves are found in the periodontium, including thinly myelinated and unmyelinated sensory fibers that express the neuropeptides substance P and calcitonin gene-related peptide among others. Tooth movement activates peripheral sensory nerve endings, which transmit painful signals to the brain after being processed at the trigeminal spinal nucleus, resulting in local expression of pain related genes, such as c-Fos. Concurrently, an attendant inflammatory process is detected in the trigeminal spinal nucleus, including activation of astrocytes, microglia and neurons. This complex neurologic reaction to tooth movement mediates orthodontic pain and also serves a source of neurogenic inflammation exhibited in the trigeminal spinal nucleus and the periodontium. Activated periodontal sensory fibers release neuropeptides in the periodontal environment, which in turn induce a local inflammatory cascade aiding in alveolar bone turnover and tooth movement per se. Control of pain with nonsteroidal anti-inflammatory drugs and other prescription or over-the-counter pain killers effectively reduce this neurologic reaction and alleviate the attendant pain, but also reduce the neurogenic inflammatory component of orthodontic tooth movement causing a slowdown in bone turnover and consequently delaying orthodontic treatment. PMID:26599119

  2. Assessment of the periodontal health status in patients undergoing orthodontic treatment with fixed or removable appliances. A microbiological and preliminary clinical study

    OpenAIRE

    Abbate, Gian Marco; Levrini, Luca; Migliori, Federico; Orru, Germano; Sauro, Salvatore; Caprioglio, Alberto

    2013-01-01

    Objectives: The use of removable orthodontic appliances minimizes the negative effects on periodontal health allowing patients to carry out oral hygiene without obstacles. The aim of this preliminary study was to evaluate microbiological and clinical changes presented during the first three months of orthodontic therapy in adults with fixed appliances and Invisalign® System (Align Technology, Santa Clara, California). Materials and Methods: Plaque Index (PI), Probing Depth (PD), Bleeding on ...

  3. Relationship between Body Mass Index, Skeletal Maturation and Dental Development in 6- to 15- Year Old Orthodontic Patients in a Sample of Iranian Population

    OpenAIRE

    Zohreh Hedayati; Fatemeh Khalafinejad

    2014-01-01

    Statement of the Problem: The prevalence of overweight and obesity has been increasing markedly in recent years. It may influence growth in pre pubertal children. Purpose: The purpose of this study was to determine whether increased Body Mass Index (BMI) is associated with accelerated skeletal maturation and dental maturation in six to fifteen years old orthodontic patients in Shiraz, Iran. Materials and Method: Skeletal maturation and dental development of 95 orthodontic patients (65 ...

  4. Three-dimensional analysis of an orthodontic delta spring

    Scientific Electronic Library Online (English)

    Fábio Rodrigo Mandello, Rodrigues; Paulo César, Borges; Marco Antônio, Luersen; Marcelo do Amaral, Ferreira.

    2014-09-01

    Full Text Available INTRODUCTION: The purpose of this study was to analyze the force system, moment-force ratios (M/F) and von Mises stresses in an orthodontic delta spring using a 3D finite element model. The M/F ratio produced by an orthodontic spring is related to the different types of tooth movement that are likel [...] y to occur in the sagittal and occlusal planes. METHODS: Analyses were performed using a 3D finite element model, and a data acquisition system was used to validate the numerical results. RESULTS: Reactive forces between 0.0 and 2.0 N were observed along the x-axis, while null values were observed along the y- and z-axes. The maximum activation that ensured geometric stability and mechanical stresses below the elastic limit of the material was 10.0 mm. CONCLUSION: The results indicate that a delta spring can provide (i) uncontrolled tipping for activation of less than 1.0 mm; (ii) controlled counterclockwise tipping for activation between 1.0 and 4.5 mm; (iii) translation for activation between 4.5 and 5.0 mm; and (iv) controlled clockwise tipping in the sagittal plane for activation between 5.0 and 10.0 mm. No tooth movement was observed in the occlusal plane for the M/F ratios observed.

  5. Biocompatibility of orthodontic adhesives in rat subcutaneous tissue

    Directory of Open Access Journals (Sweden)

    Rogério Lacerda dos Santos

    2010-10-01

    Full Text Available ABSTRACT OBJECTIVE: The objective of the present study was to verify the hypothesis that no difference in biocompatibility exists between different orthodontic adhesives. MATERIAL AND METHODS: Thirty male Wistar rats were used in this study and divided into five groups (n=6: Group 1 (control, distilled water, Group 2 (Concise, Group 3 (Xeno III, Group 4 (Transbond XT, and Group 5 (Transbond plus Self-Etching Primer. Two cavities were performed in the subcutaneous dorsum of each animal to place a polyvinyl sponge soaked with 2 drops of the respective adhesive in each surgical loci. Two animals of each group were sacrificed after 7, 15, and 30 days, and their tissues were analyzed by using an optical microscope. RESULTS: At day 7, Groups 3 (Transbond XT and 4 (Xeno III showed intense mono- and polymorphonuclear inflammatory infiltrate with no differences between them, whereas Groups 1 (control and 2 (Concise showed moderate mononuclear inflammatory infiltrate. At day 15, severe inflammation was observed in Group 3 (Transbond XT compared to other groups. At day 30, the same group showed a more expressive mononuclear inflammatory infiltrate compared to other groups. CONCLUSION: Among the orthodontic adhesive analyzed, it may be concluded that Transbond XT exhibited the worst biocompatibility. However, one cannot interpret the specificity of the data generated in vivo animal models as a human response.

  6. Effect of Low Llevel Therapy on Orthodontic Movement in Human

    Directory of Open Access Journals (Sweden)

    Hosseini MH

    2011-12-01

    Full Text Available Background and Aims: Lasers with different characteristics have been used to stimulate orthodontic tooth movement. Considering the contradictory findings in this regard, this study was designed to assess the effect of low level laser therapy (LLLT on the rate of orthodontic tooth movement.Materials and Methods: In this randomized clinical trial study, 12 patients (4 boys and 8 girls; average age:16.9 ± 3.4 with extracted upper first premolars and required canine retraction into extraction site were included. While in both sides canines were retracted by NiTi coil spring, one side was exposed to GaAlAs laser (890 nm. LLLT was done (on the buccal and palatal mucosa by slow movement of probe at the beginning of the first month. Impression and cast fabrication performed at the beginning of retraction, one and two months later. The amount of retraction on the cast was measured with the aid of a reference plaque fabricated on the rogae using a digital caliper. Data were analyzed using paired sample T-test and one-sample Kolmogorov-Simirnov test. Results: There was no significant difference in the amounts of canine movement between laser exposed and control sides (P>0.05. Conclusion: The energy dose of laser used in this study (72 J per each tooth was not appropriate for increasing dental movement.

  7. Clinical evaluation of periodontal health during orthodontic treatment with fixed appliances

    Directory of Open Access Journals (Sweden)

    H?n?oiu T.

    2014-12-01

    Full Text Available Objectives: Fixed orthodontic appliances make daily application of oral hygiene standard procedures more difficult and in time may lead to accumulation of oral biofilms and development of gingivitis and hyperplasia. The aim of the study is to evaluate the periodontal health expressed by clinical indices in patients under orthodontic treatment with fixed appliances, according to different oral hygene maintenance programs. Material and method: We performed a randomized prospective study on 60 patients with fixed orthodontic appliances (17-25 years of age devided in three study groups. The clnical indices recorded were: modified gingival index, plaque index and sulcular bleeding index. Statistical analysis or the results were carried out using Student t test. Results: The patients were randomly divided into three groups: group A-patients were instructed to use electric brush, water flosser and interdental brush, group B- electric brush, interdental brush and fluoride and group C- manual brushing and fluoride. Statistical comparison of the values of the indexes with the Student t test for independent samples showed statistically significant differences in all three groups of patients studied between initial and final values of all recorded clinical parameters. Conclusions: Fixed orthodontics do not induce periodontal disease if basic principles of oral hygiene are followed in compliant patients, which are correctly instructed to deal with real challenge, represented by complete elimination of debris and bacterial accumulation.

  8. Distraction-like phenomena in maxillary bone due to application of orthodontic forces in ovariectomized rats

    Directory of Open Access Journals (Sweden)

    Apostolos I Tsolakis

    2012-01-01

    Full Text Available Background: Orthodontic forces may not only influence the dentoalveolar system, but also the adjacent and surrounding cortical bone. Aim: Since there is very limited information on this issue, we aimed to study the possible changes in maxillary cortical bone following the application of heavy orthodontic forces in mature normal and osteoporotic rats. Materials and Methods: Twenty-four 6-month-old female rats were selected and divided into an ovariectomized group and a normal group. In both groups, the rats were subjected to a 60 grFNx01 orthodontic force on the upper right first molar for 14 days. Results: In both groups, histological sections showed that the application of this force caused hypertrophy and fatigue failure of the cortical maxillary bone. The osteogenic reaction to distraction is expressed by the formation of subperiosteal callus on the outer bony side, resembling that seen in distracted bones. Conclusion: From this study we concluded that heavy experimental orthodontic forces in rats affect the maxillary cortical bone. The osteogenic reaction to these forces, expressed histologically by subperiosteal callus formation, is similar to that seen in distraction osteogenesis models.

  9. Randomized clinical controlled trial on the effectiveness of conventional and orthodontic manual toothbrushes

    Directory of Open Access Journals (Sweden)

    Lisiane Krieger Gomes

    2012-08-01

    Full Text Available The objective of this study was to compare the effectiveness of two manual toothbrushes (conventional and orthodontic. The following clinical parameters were used: VPI (visible plaque index and GBI (gingival bleeding index. Patients, 64 total (30 males and 34 females, in the permanent dentition, with a mean age of 17.8 years, were randomly selected from a practice specializing in orthodontics. Each participant received audio-visual instructions on oral hygiene as well as a kit of materials containing two manual toothbrushes (orthodontic and conventional. Each toothbrush was randomly allocated to one side of the mouth (split-mouth design and used for a period of approximately 4 weeks. The VPI and GBI were measured by a single calibrated examiner before (T0 and after (T1 the implementation of interventions. The Mann-Whitney test was used to compare the VPI values between the groups, and the Student t-test for independent samples was used to compare GBI values. The level of significance was set at 5%. No statistically significant difference was observed between the groups at T0 for both VPI and GBI, and at T1 for the GBI. The manual orthodontic toothbrush produced a statistically lower VPI (P < 0.05 at T1, but this did not seem to be of clinical importance.

  10. Randomized clinical controlled trial on the effectiveness of conventional and orthodontic manual toothbrushes

    Scientific Electronic Library Online (English)

    Lisiane Krieger, Gomes; Carlos Frederico, Sarmento; Flávio Roberto Guerra, Seabra; Patrícia Bittencourt Dutra dos, Santos; Fábio Henrique de Sa Leitão, Pinheiro.

    2012-08-01

    Full Text Available The objective of this study was to compare the effectiveness of two manual toothbrushes (conventional and orthodontic). The following clinical parameters were used: VPI (visible plaque index) and GBI (gingival bleeding index). Patients, 64 total (30 males and 34 females), in the permanent dentition, [...] with a mean age of 17.8 years, were randomly selected from a practice specializing in orthodontics. Each participant received audio-visual instructions on oral hygiene as well as a kit of materials containing two manual toothbrushes (orthodontic and conventional). Each toothbrush was randomly allocated to one side of the mouth (split-mouth design) and used for a period of approximately 4 weeks. The VPI and GBI were measured by a single calibrated examiner before (T0) and after (T1) the implementation of interventions. The Mann-Whitney test was used to compare the VPI values between the groups, and the Student t-test for independent samples was used to compare GBI values. The level of significance was set at 5%. No statistically significant difference was observed between the groups at T0 for both VPI and GBI, and at T1 for the GBI. The manual orthodontic toothbrush produced a statistically lower VPI (P

  11. Comparison of External Apical Root Resorption after Orthodontic Treatment with Two Appliances (Standard Edgewise and MBT

    Directory of Open Access Journals (Sweden)

    V. Mollabashi

    2016-01-01

    Full Text Available Introduction & Objective: The aim of this study was todeterminetheamount of external apical root resorption(EARRwithin two orthodontic appliances (standard edgewise and MBT. Material & Methods In this retrospective study, panoramic radiographs of 83 orthodontic patients (27 male and 56 female were evaluated. 46 patients had been treated with standard edgewise appliance (29 patients with extraction and 17 patients without extraction and 37 patients had been treated with MBT appliance (27 patients with extraction and 10 patients without extraction.EARR were evaluated in 24 teeth (anterior teeth, premolars and first molars in each patient. SPSS software and ordinal regression test were used for statistical analysis. Result: In this study the most EARR was seen in upper lateral incisors, then lower lateral incisors.EARR in upper canines and lower second premolars was significantly related to extraction of first premolarin MBT appliance. In non extraction cases, EARR was not related to the orthodontic appliance. Conclusion: Incisors teeth are the most disposed teeth to EARR. Orthodontic treatment with extraction increased EARR in canines and second premolars. MBT appliance may increase EARR. Sci J Hamadan Univ Med Sci . 2016; 22 (4 :316-322

  12. Changes in orthodontic treatment modalities in the past 20 years: exploring the link between technology and scientific evidence.

    Science.gov (United States)

    Bradley, T Gerard

    2013-01-01

    STATEMENT OF THE ISSUE: Is there a link between the many perceived advances in orthodontic techniques/therapy and science in the past 20 years? The purpose of this paper is to take five topics and match the perceptions with the scientific evidence. The variety of appliances and the swings in treatment philosophy have been dramatic, including the swing from extraction to non-extraction therapy, the introduction of space-age wires, appliances that grow mandibles, the introduction and extraordinary growth of Invisalign, and reduced friction brackets to reduce treatment time, all with claims by manufacturers of better results than ever before. The focus is on faster treatment, reduced visits/appointments and superior results. Most of these 'advancements' represent what has been the 'juggernaut of technology'. Five questions are posed, and an evidence-based approach is used to critically examine the literature in these selected topics. PMID:23729055

  13. Assessment of the mechanical properties of glass ionomer cements for orthodontic cementation

    Directory of Open Access Journals (Sweden)

    Marcel M. Farret

    2012-12-01

    Full Text Available OBJECTIVE: To evaluate the mechanical properties of three glass ionomers cements (GICs used for band cementation in Orthodontics. METHODS: Two conventional glass ionomers (Ketac Cem Easy mix/3M-ESPE and Meron/Voco and one resin modified glass ionomer (Multi-cure Glass ionomer/3M-Unitek were selected. For the compressive strength and diametral tensile strength tests, 12 specimens were made of each material. For the microhardness test 15 specimens were made of each material and for the shear bond strength tests 45 bovine permanent incisors were used mounted in a self-cure acrylic resin. Then, band segments with a welded bracket were cemented on the buccal surface of the crowns. For the mechanical tests of compressive and diametral tensile strength and shear bond strength a universal testing machine was used with a crosshead speed of 1,0 mm/min and for the Vickers microhardness analysis tests a Microdurometer was used with 200 g of load during 15 seconds. The results were submitted to statistical analysis through ANOVA complemented by Tukey's test at a significance level of 5%. RESULTS: The results shown that the Multi-Cure Glass Ionomer presented higher diametral tensile strength (p OBJETIVO: avaliar as propriedades mecânicas de três cimentos de ionômero de vidro (CIVs utilizados para cimentação de anéis ortodônticos. MÉTODOS: foram utilizados dois CIVs convencionais (Ketac Cem Easy mix/3M-ESPE e Meron/Voco e um CIV modificado por resina (Multi-Cure Glass ionomer/3M-Unitek. Para os testes de resistência à compressão e tração diametral, foram confeccionados 12 corpos de prova de cada material. Para os testes de microdureza, foram confeccionados 15 corpos de prova de cada material; para os testes de resistência de união ao cisalhamento, foram utilizados 45 dentes bovinos incluídos em resina acrílica, sobre os quais foi cimentada uma lâmina de anel ortodôntico com braquete soldado a ela para a realização dos ensaios. Para os testes de compressão, tração diametral e cisalhamento, foi utilizada uma máquina universal de ensaios a uma velocidade de 1mm/min; para os testes de microdureza Vickers, foi utilizado um microdurômetro com 200g de carga durante 15 segundos. Os resultados foram submetidos à análise estatística ANOVA, complementada pelo teste de Tukey ao nível de significância de 5%. RESULTADOS: os resultados demonstraram que o Multi-Cure Glass Ionomer apresentou resistência à tração diametral significativamente maior (p < 0,01 e maior resistência à compressão (p = 0,08 em relação aos CIVs convencionais. Além disso, o Ketac Cem apresentou microdureza significativamente maior que os demais materiais (p < 0,01. CONCLUSÃO: o CIV modificado por resina apresentou propriedades mecânicas superiores às dos CIVs convencionais, que, por sua vez, apresentaram poucas diferenças entre si.

  14. A portfolio of dilemmas: Experimental evidence on choice bracketing in a mini-trust game

    OpenAIRE

    Ding, Jieyao

    2012-01-01

    Bracketing is a mental procedure about how people deal with multiple tasks. If a decision maker handles all the tasks at the same time, it is called broad bracketing. If she handles the tasks separately, e.g., one or a few tasks each time, it is called narrow bracketing. This paper experimentally investigates the effect of broad versus narrow bracketing in the context of a mini-trust game. The result shows that, in the narrow bracketing treatment, the investor (first mover) is more likely to ...

  15. Efficiency in bracket bonding with the use of pretreatment methods to tooth enamel before acid etching: sodium hypochlorite vs. hydrogen peroxide techniques

    Scientific Electronic Library Online (English)

    Hermann, Rivera-Prado; Ángeles, Moyaho-Bernal; Alejandro, Andrade-Torres; Guillermo, Franco-Romero; Álvaro, Montiel-Jarquín; Claudia, Mendoza-Pinto; Eugenio, García-Cano; Ana K, Hernández-Ruíz.

    2015-04-01

    Full Text Available Las fallas de adhesion se producen por la existencia de la biopelicula en la superficie del organo dental, ya que es impermeable y no permite el contacto en muchas areas, de manera que disminuye el efecto del grabado acido; el cual tiene la capacidad de disolver selectivamente los tejidos calcificad [...] os, pero no parece eliminar la biopelicula en la superficie dental, por lo tanto, no se lleva a cabo la suficiente fuerza de adhesion en la interfase diente-bracket. El objetivo es comparar la eficiencia en la adhesion de los brackets con el empleo de dos metodos de pre-tratamientos de la superficie del esmalte, el hipoclorito de sodio vs. peroxido de hidrogeno. Estudio comparativo, transversal, in vitro. Se evaluaron 75 premolares extraidos con fines ortodoncicos, tres grupos de 25 dientes, asignados aleatoriamente con alguna de las dos tecnicas de pre-tratamiento al esmalte, hipoclorito de sodio al 5.25%, peroxido de hidrogeno al 3.5% y un grupo control. La tecnica de pre-tratamiento al esmalte mas eficiente para la fuerza de adhesion a los brackets fue el hipoclorito de sodio, con una media de 17.15 (Kg/F), se observaron diferencias significativas inter-grupos (p= 0.001). Las pruebas post hoc para las fuerzas de adhesion mostraron diferencia estadistica - mente significativa para la tecnica de hipoclorito de sodio/ grupo control (p=.001). La utilizacion de hipoclorito de sodio ayuda a mejorar la adhesion de los brackets en la superficie del esmalte. Abstract in english Bond failures are produced by the existence of biofilm on the tooth surface. Because biofilm is impermeable, it prevents contact in many areas, reducing the etching effect which selectively dissolves calcified tissues but does not seem to eliminate biofilm from the tooth surface, and thus the bond b [...] etween the tooth and the bracket is not strong enough. The aim of this study is to compare bracket bonding efficiency with two dental surface pretreatments: sodium hypochlorite vs. hydrogen peroxide techniques. This was a cross-sectional, comparative, in vitro study. Seventy-five premolars extracted for orthodontic purposes were evaluated. They were divided into three groups of 25 teeth and assigned randomly toone of the pretreatment techniques (5.25%sodium hypochlorite or 3.5% hydrogen peroxide) or to a control group. The most efficient pretreatment technique for bonding to brackets was sodium hypochlorite, with an average of 17.15 (kg/F). Significant differences were observed between groups (p=0.0001). The post hoc bond strength test showed statistically significant differences between the sodium hypochlorite technique and the control group (p=0.0001). The sodium hypochlorite technique improves bracket adhesion to tooth enamel.

  16. Comparison of shear bond strength of rebonded brackets with four methods of adhesive removal.

    Science.gov (United States)

    Yassaei, S; Aghili, H; KhanPayeh, E; Goldani Moghadam, M

    2014-09-01

    Rebonding of a dislodge bracket is considered as an economic saving option which can be done with use of in-office methods or by commercial recycling. The aim of this study was to compare the shear rebond strength (SRS) of brackets recycled with different resin removal methods. Eighty premolars were divided into four experimental groups. The teeth were bonded with metal brackets. The brackets were debonded and adhesive remnants were removed from bracket bases by means of Er:YAG laser, sandblasting, direct flame, and CO2 laser, respectively. Following adhesive removal from enamel surfaces with carbide bur, recycled brackets were rebonded. Finally, all brackets were debonded with a Dartec testing machine and the SRS values were determined. The SRS values of groups 3 and 4 were significantly lower compare to other groups (P value < 0.001). SEM examination showed complete adhesive removal from bracket base cleaned with Er:YAG laser irradiation. Microroughening of the base of sandblasted bracket was observed in the SEM image. Resin removal with direct flame and CO2 laser irradiation was incomplete. Er:YAG laser recycling of brackets is an efficient in-office method of reconditioning which caused minimum damage to the bracket base. PMID:23568626

  17. Esthetic perception and economic value of orthodontic appliances by lay Brazilian adults

    Scientific Electronic Library Online (English)

    Daniela, Feu; Fernanda, Catharino; Candice Belchior, Duplat; Jonas, Capelli Junior.

    2012-10-01

    Full Text Available OBJETIVO: avaliar a percepção de brasileiros adultos leigos para diferentes aparelhos ortodônticos e sua influência na valorização econômica do tratamento, considerando o nível socioeconômico, idade e sexo dos avaliadores. MÉTODOS: oito combinações de aparelhos ortodônticos e alinhadores foram coloc [...] adas em um adulto com bom alinhamento dentário, e fotografias frontais foram feitas para compor um álbum de imagens de pesquisa. Uma amostra de adultos (n = 252, mediana = 26 anos) classificou cada imagem por (1) atratividade, em uma escala visual analógica, e (2) disposição a pagar a mais para realizar o tratamento com um aparelho estético em relação a um aparelho metálico e em relação a um alinhador. Comparações da atratividade dos aparelhos foram realizadas utilizando-se o teste de Friedman e o post-hoc de Dann. A correlação entre a valorização econômica, nível socioeconômico, idade, sexo e percepção estética foi calculada com a análise de correlação de Spearman. RESULTADOS: a atratividade dos aparelhos ortodônticos variou significativamente, na seguinte hierarquia: alinhadores > aparelhos de safira > aparelhos metálicos tradicionais e autoligáveis > aparelhos dourados. A correlação entre a atratividade dos aparelhos e a disposição em pagar mais por eles foi fraca. Contudo, ter melhor nível socioeconômico e idade entre 17 e 26 anos aumentou significativamente a disposição de pagar dos avaliadores. CONCLUSÕES: alinhadores e braquetes de safira com fio estético foram considerados as opções de maior atratividade para essa amostra. Entretanto, os avaliadores não estiveram dispostos a pagar a mais para realizar seus tratamentos com os dispositivos que julgaram mais estéticos, sendo, contudo, significativamente influenciados por seu nível socioeconômico e idade. Abstract in english OBJECTIVE: To evaluate the esthetic perception of different appliances by Brazilian lay adults and its influence in the attributed value of orthodontic treatment, considering evaluators' socioeconomic status, age and gender. METHODS: Eight different combinations of orthodontic appliances and clear t [...] ray aligners were placed in a consenting adult with pleasing smile. Standardized frontal photographs were captured and incorporated into a research album. A sample of adults (n = 252, median = 26 years old) were asked to rate each image for (1) its attractiveness on a visual analog scale and (2) the willingness to pay (WTP) for a cosmetic appliance when compared to a standard metalic appliance and a clear tray aligner. Comparisons between the appliances' attractiveness were performed using the Friedman's test and Dann's post-hoc test. Correlation between appliances' attributed value, socioeconomic status, age, gender, and esthetic perception was assessed using Spearman's correlation analysis. RESULTS: Attractiveness ratings of orthodontic appliances varied significantly in the following hierarchy: Clear aligners>sapphire brackets>self-ligating/conventional stainless steel brackets>and golden metal appliances. The correlation between WTP and esthetic perception was week. However, for individuals with better socioeconomic status and aged between 17-26 years old significantly, a significantly higher WTP was found. CONCLUSION: Clear aligners and sapphire brackets with esthetic archwire were considered better esthetic options in this sample. Nevertheless, patients were not willing to pay more money for appliances they deemed more esthetic, however, they were significantly influenced by their socioeconomic level and age.

  18. The effect of photobiomodulation on root resorption during orthodontic treatment

    OpenAIRE

    Nimeri G; Kau CH; Corona R; Shelly J

    2014-01-01

    Ghada Nimeri, Chung H Kau, Rachel Corona, Jeffery Shelly Department of Orthodontics, University of Alabama, Birmingham, AL, USA Abstract: Photobiomodulation is used to accelerate tooth movement during orthodontic treatments. The changes in root morphology in a group of orthodontic patients who received photobiomodulation were evaluated using the cone beam computed tomography technique. The device used is called OrthoPulse, which produces low levels of light with a near infrared wavelength of...

  19. Modified miniplates for temporary skeletal anchorage in orthodontics

    DEFF Research Database (Denmark)

    Cornelis, Marie; Scheffler, Nicole R; Mahy, Pierre; Siciliano, Sergio; De Clerck, Hugo J; Tulloch, J F Camilla

    2008-01-01

    PURPOSE: Skeletal anchorage systems are increasingly used in orthodontics. This article describes the techniques of placement and removal of modified surgical miniplates used for temporary orthodontic anchorage and reports surgeons' perceptions of their use. PATIENTS AND METHODS: We enrolled 97 consecutive orthodontic patients having miniplates placed as an adjunct to treatment. A total of 200 miniplates were placed by 9 oral surgeons. Patients and surgeons completed questionnaires after placeme...

  20. Cytokines and VEGF Induction in Orthodontic Movement in Animal Models

    OpenAIRE

    Perillo, L.; Polimeni, A.; De Rosa, A.; Berrino, L.; Pierantoni, G. M.; Feola , A; Cito, L.; A. Monsurrò; Di Domenico, M; F. D'apuzzo

    2012-01-01

    Orthodontics is a branch of dentistry that aims at the resolution of dental malocclusions. The specialist carries out the treatment using intraoral or extraoral orthodontic appliances that require forces of a given load level to obtain a tooth movement in a certain direction in dental arches. Orthodontic tooth movement is dependent on efficient remodeling of periodontal ligament and alveolar bone, correlated with several biological and mechanical responses of the tissues surrounding the teeth...

  1. Orthodontic Treatment of a Mandibular Incisor Extraction Case with Invisalign

    OpenAIRE

    Zawawi, Khalid H.

    2014-01-01

    Mandibular incisor extraction for orthodontic treatment is considered an unusual treatment option because of the limited number of patients that meet the criteria for such treatment. Accurate diagnosis and treatment planning is essential to achieve the desired results. Adult orthodontic patients are increasingly motivated by esthetic considerations and reject the idea of conventional fixed appliances. In recent years, Invisalign appliances have gained tremendous attention for orthodontic trea...

  2. A quantum Goldman bracket in (2 + 1) quantum gravity

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, J E [Dipartimento di Fisica Teorica, Universita degli Studi di Torino and Istituto Nazionale di Fisica Nucleare, Sezione di Torino, via Pietro Giuria 1, 10125 Torino (Italy); Picken, R F [Departamento de Matematica and CAMGSD-Centro de Analise Matematica, Geometria e Sistemas Dinamicos, Instituto Superior Tecnico, Technical University of Lisbon, Avenida Rovisco Pais, 1049-001 Lisboa (Portugal)], E-mail: nelson@to.infn.it, E-mail: rpicken@math.ist.utl.pt

    2008-08-01

    In the context of quantum gravity for spacetimes of dimension (2 + 1), we describe progress in the construction of a quantum Goldman bracket for intersecting loops on surfaces. Using piecewise linear paths in R{sup 2} (representing loops on the spatial manifold, i.e. the torus) and a quantum connection with noncommuting components, we review how holonomies and Wilson loops for two homotopic paths are related by phases in terms of the signed area between them. Paths rerouted at intersection points with other paths occur on the rhs of the Goldman bracket. To better understand their nature we introduce the concept of integer points inside the parallelogram spanned by two intersecting paths, and show that the rerouted paths must necessarily pass through these integer points.

  3. Derivation of the Hall and Extended Magnetohydrodynamics Brackets

    CERN Document Server

    D'Avignon, E C; Lingam, M

    2015-01-01

    There are several plasma models intermediate in complexity between ideal magnetohydrodynamics (MHD) and two-fluid theory, with Hall and Extended MHD being two important examples. In this paper we investigate several aspects of these theories, with the ultimate goal of deriving the noncanonical Poisson brackets used in their Hamiltonian formulations. We present fully Lagrangian actions for each, as opposed to the fully Eulerian, or mixed Eulerian-Lagrangian, actions that have appeared previously. As an important step in this process we exhibit each theory's two advected fluxes (in analogy to ideal MHD's advected magnetic flux), discovering also that with the correct choice of gauge they have corresponding Lie-dragged potentials resembling the electromagnetic vector potential, and associated conserved helicities. Finally, using the Euler-Lagrange map, we show how to derive the noncanonical Eulerian brackets from canonical Lagrangian ones.

  4. Algebric generalization of symmetry Dirac bracket. Application to field theory

    International Nuclear Information System (INIS)

    The A set of observable of a physical system with finite e infinite number of degrees of freedom and submitted to certain constraint conditions, is considered. Using jordan algebra structure on A in relation to bymmetric Poisson bracket obtained by Droz-Vincent, a jordan product is obtained on the A/I quocient set with regard to I ideal generated by constraints of second class. It is shown that this product on A/I corresponds to symmetric Dirac bracket. The developed formulation is applied to a system corresponding to harmonic oscillators, non relativistic field, Rarita-Schwinger field and the possibility of its utilization in fermionic string theories is discussed. (M.C.K.)

  5. A Quantum-Classical Brackets from p-Mechanics

    CERN Document Server

    Kisil, V V

    2005-01-01

    We provide an answer to the long standing problem of mixing quantum and classical dynamics within a single formalism. The construction is based on p-mechanical derivation (quant-ph/0212101, quant-ph/0304023) of quantum and classical dynamics from the representation theory of the Heisenberg group. To achieve a quantum-classical mixing we take the product of two copies of the Heisenberg group which represent two different Planck's constants. In comparison with earlier guesses our answer contains an extra term of analytical nature, which was not obtained before in purely algebraic setup. Keywords: Moyal brackets, Poisson brackets, commutator, Heisenberg group, orbit method, representation theory, Planck's constant, quantum-classical mixing

  6. Risk factors for low molar bite force in adult orthodontic patients

    DEFF Research Database (Denmark)

    Andersen, Malene Krogh; Sonnesen, Ane Liselotte

    2013-01-01

    The aim was to analyse which parameters in a standard orthodontic material are most important for identifying factors for low bite force. Such analyses have not previously been reported in adult orthodontic patients. The sample comprised 95 adults (67 females and 28 males) aged 18-55 years sequentially admitted for conventional orthodontic treatment. All subjects had moderate to severe malocclusions. Bite force was measured by a pressure transducer, craniofacial dimensions and head posture were measured on profile radiographs, number of teeth in contact were evaluated with a plastic strip in intercuspidal position, and symptoms and signs of temporomandibular disorders (TMD) were evaluated by TMD screening. Associations were assessed by Spearman correlations, Wilcoxon signed-rank sum test, and multiple stepwise regression analyses. Associations were found between bite force and craniofacial dimensions as mandibular prognathia (S-N-Pg, P <0.05; S-N-sm, P <0.05), sagittal jaw relationship (SS-N-Pg, P <0.05), mandibular inclination (NSL/ML, P <0.05), and mandibular plane angle (ML/RL, P <0.01) and between bite force and TMD symptoms (P <0.05) and TMD signs (P <0.05). Multiple regression analysis showed that gender (P <0.001), TMD symptoms (P <0.01), and mandibular plane angle (P <0.001) were the most important factors for the magnitude of the bite force in adult orthodontic patients (R(2) = 0.32). The results showed that particularly women with TMD symptoms and an increased mandibular plane angle are at risk of having low bite force. This may prove valuable in the clinic, especially in orthodontic cases with an increased need for vertical anchorage during treatment.

  7. An Analytical Study on an Orthodontic Index: Index of Complexity, Outcome and Need (ICON)

    Science.gov (United States)

    Torkan, Sepide; Pakshir, Hamid Reza; Fattahi, Hamid Reza; Oshagh, Morteza; Momeni Danaei, Shahla; Salehi, Parisa; Hedayati, Zohreh

    2015-01-01

    Statement of the Problem The validity of the Index of Complexity, Outcome and Need (ICON) which is an orthodontic index developed and introduced in 2000 should be studied in different ethnic groups. Purpose The aim of this study was to perform an analysis on the ICON and to verify whether this index is valid for assessing both the need and complexity of orthodontic treatment in Iran. Materials and Method Five orthodontists were asked to score pre-treatment diagnostic records of 100 patients with a uniform distribution of different types of malocclusions determined by Dental Health Component of the Index of Treatment Need. A calibrated examiner also assessed the need for orthodontic treatment and complexity of the cases based on the ICON index as well as the Index of Orthodontic Treatment Need (IOTN). 10 days later, 25% of the cases were re-scored by the panel of experts and the calibrated orthodontist. Results The weighted kappa revealed the inter-examiner reliability of the experts to be 0.63 and 0.51 for the need and complexity components, respectively. ROC curve was used to assess the validity of the index. A new cut-off point was adjusted at 35 in lieu of 43 as the suggested cut-off point. This cut-off point showed the highest level of sensitivity and specificity in our society for orthodontic treatment need (0.77 and 0.78, respectively), but it failed to define definite ranges for the complexity of treatment. Conclusion ICON is a valid index in assessing the need for treatment in Iran when the cut-off point is adjusted to 35. As for complexity of treatment, the index is not validated for our society. It seems that ICON is a well-suited substitute for the IOTN index. PMID:26331142

  8. Avaliação da força de tração em braquetes colados pela técnica indireta com diferentes sistemas de adesão Evaluation of tensile strength of brackets bonded by indirect technique

    Directory of Open Access Journals (Sweden)

    André Tortamano

    2007-06-01

    Full Text Available OBJETIVO: o objetivo do presente estudo foi avaliar a resistência à tração de braquetes ortodônticos colados pela técnica indireta e pela técnica direta convencional. METODOLOGIA: foram utilizados 50 pré-molares humanos íntegros, recém-extraídos por motivos ortodônticos. Esses dentes foram divididos em 5 grupos, nos quais foram colados braquetes ortodônticos metálicos (Abzil-Brasil com as resinas compostas ortodônticas Concise (3M-Unitek-EUA e Transbond XT (3M-Unitek-EUA - utilizadas em ambas as técnicas, direta e indireta - e Transbond Sondhi (3M-Unitek-EUA - desenvolvida exclusivamente para a técnica indireta. O grupo I (controle I foi objeto de colagem direta com Transbond XT; no grupo II (controle II procedeu-se à colagem direta com Concise o grupo III recebeu colagem indireta com Concise; o grupo IV foi submetido à colagem indireta com Transbond XT e no grupo V foi realizada colagem indireta com Transbond Sondhi. Na técnica direta, o braquete foi colado diretamente sobre o esmalte após condicionamento ácido e aplicação de adesivo. Na técnica indireta, os braquetes foram colados primeiramente sobre modelo de gesso e depois transferidos para o dente, com o auxílio de moldeira individualizada. Os corpos-de-prova foram submetidos a testes de tração (Instron 4400 e os resultados foram objeto de testes estatísticos de análise de variância e de Tukey a 1%. RESULTADOS: os grupos III e V revelaram resultados significantemente menores que os dos dois grupos controles. CONCLUSÃO: a força obtida na colagem indireta com a resina Transbond XT não difere da força obtida na colagem direta com as resinas Concise e Transbond XT.AIM: The purpose of this study was to evaluate the bonding strength of brackets for direct and indirect bonding techniques. METHODS: Were used 50 human premolars recently extracted for orthodontic reasons. These teeth were divided in 5 groups and metalic orthodontic brackets (Abzil-Brazil were bonded by direct and indirect techniques with orthodontic composite resins: group I (Control I - direct bonding using Concise (3M-Unitek-EUA; group II (Control II - direct bonding using Transbond (3M-Unitek-EUA with XT bond system; group III - indirect bonding using Concise (3M-Unitek-EUA; group IV - indirect bonding using Transbond (3M-Unitek-EUA with XT bonding system; group V - indirect bonding using Transbond with Sondhi bonding system (3M-Unitek-EUA. The Sondhi bonding system was designed specifically for indirect bonding. In the direct bonding technique brackets were placed directly on the enamel surface, in the indirect technique brackets were first bonded in a cast of the teeth and then they were transfered by means of a tray to the teeth. The samples were submitted to tensile tests (Instron 4400 and the statistical ANOVA and Tukey ( 1% tests were applied. RESULTS: The groups III and V showed lower bond strength than control groups (I and II, there was no significant difference between group IV and control groups (I and II. CONCLUSION: It was concluded that for indirect bonding technique only the Transbond XT (3M didn't show significant statistical difference when compared to the direct bonding technique.

  9. [Orthognathic surgery: specific aspects of surgical-orthodontic preparations].

    Science.gov (United States)

    Raberin, M; Mauhourat, S

    2014-09-01

    Orthodontic preparation, mandatory before surgery, has benefited from great innovations in periodontics and implantology. The objectives of current orthodontics are short procedures and compliance with dental capital. Using bone anchorage changes treatment modalities for dental compensation. Piezo-electric surgery has become the first line procedure for osteotomies by improving surgical precision and downgrading nerve complications. Alveolar corticotomy has allowed decreasing orthodontic preparation time by causing an acceleration of tooth displacement. Primary transverse and sagittal surgery allow improving or protecting periodontal and muscular systems during orthodontic preparation. Normalization of oro-facial functions is an essential factor of surgical stability. The initial dysfunction justifies an appropriate and rapid management. PMID:25081489

  10. External apical root resorption in maxillary incisors in orthodontic patients: associated factors and radiographic evaluation

    International Nuclear Information System (INIS)

    This study was performed to evaluate the incidence and degree of external apical root resorption of maxillary incisors after orthodontic treatment and to evaluate particular associated factors related to external apical root resorption. The records and maxillary incisor periapical radiographs of 181 patients were investigated. Crown and root lengths were measured and compared on the pre- and post-treatment periapical radiographs. Crown length was measured from the center of the incisal edge to the midpoint of the cemento-enamel junction (CEJ). Root length was measured from the CEJ midpoint to the root apex. A correction factor for the enlargement difference was used to calculate root resorption. The periapical radiographs of 564 teeth showed that the average root resorption was 1.39±1.27 (8.24±7.22%) and 1.69±1.14 mm (10.16±6.78%) for the maxillary central and lateral incisors, respectively. The results showed that the dilacerated or pointed roots, maxillary premolar extraction cases, and treatment duration were highly significant factors for root resorption (p<0.001). Allergic condition was a significant factor at p<0.01. Age at the start of treatment, large overjet, and history of facial trauma were also factors significantly associated with root resorption (p<0.05). There was no statistically significant difference in root resorption among the factors of gender, overbite, tongue-thrusting habit, types of malocclusion, and types of bracket. These results suggested that orthodontic treatment should be carefully performed in pre-treatment extraction patients who have pointed or dilacerated roots and need long treatment duration.

  11. External apical root resorption in maxillary incisors in orthodontic patients: associated factors and radiographic evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Nanekrungsan, Kamonporn [Dept. of Dentistry, Overbrook Hospital, Chiang Rai (Thailand); Patanaporn, Virush; Janhom, Apirum; Korwanich, Narumanus [Dept. of Chiang Mai University, Chiang Mai (Thailand)

    2012-09-15

    This study was performed to evaluate the incidence and degree of external apical root resorption of maxillary incisors after orthodontic treatment and to evaluate particular associated factors related to external apical root resorption. The records and maxillary incisor periapical radiographs of 181 patients were investigated. Crown and root lengths were measured and compared on the pre- and post-treatment periapical radiographs. Crown length was measured from the center of the incisal edge to the midpoint of the cemento-enamel junction (CEJ). Root length was measured from the CEJ midpoint to the root apex. A correction factor for the enlargement difference was used to calculate root resorption. The periapical radiographs of 564 teeth showed that the average root resorption was 1.39{+-}1.27 (8.24{+-}7.22%) and 1.69{+-}1.14 mm (10.16{+-}6.78%) for the maxillary central and lateral incisors, respectively. The results showed that the dilacerated or pointed roots, maxillary premolar extraction cases, and treatment duration were highly significant factors for root resorption (p<0.001). Allergic condition was a significant factor at p<0.01. Age at the start of treatment, large overjet, and history of facial trauma were also factors significantly associated with root resorption (p<0.05). There was no statistically significant difference in root resorption among the factors of gender, overbite, tongue-thrusting habit, types of malocclusion, and types of bracket. These results suggested that orthodontic treatment should be carefully performed in pre-treatment extraction patients who have pointed or dilacerated roots and need long treatment duration.

  12. Association of orthodontic treatment needs and oral health-related quality of life in Saudi children seeking orthodontic treatment

    OpenAIRE

    Hassan AH; Hassan MH; Linjawi AI

    2014-01-01

    Ali H Hassan,1 Mona HA Hassan,2,3 Amal I Linjawi11Department of Orthodontics, 2Department of Dental Public Health, Faculty of Dentistry, King Abdulaziz University, Jeddah, Kingdom of Saudi Arabia; 3Department of Biostatistics, High Institute of Public Health, Alexandria University, Egypt Introduction: The objective was to assess the effects of different orthodontic treatment needs on the oral health-related quality of life (OHRQoL) of Saudi children seeking orthodontic treatment as perceived ...

  13. A Systematic Review of Individual Motivational Factors in Orthodontic Treatment: Facial Attractiveness as the Main Motivational Factor in Orthodontic Treatment

    OpenAIRE

    Lusine Samsonyanová; Zdenek Broukal

    2014-01-01

    Introduction. Physical, mental, and social consequences of malocclusion may impact the quality of life. The aim of this review is to describe main factors motivating parents for orthodontic treatment for their children. Methods. A systematic review study design was used to identify articles analyzing different motivational factors in orthodontic treatment appearing in Medline database, EMBASE, and Google Scholar. The search terms used were teasing, motivating factors, orthodontics, malocclusi...

  14. Effects of Immediate Orthodontic and Orthopedic Forces on Peri-Miniscrew Bones: Histomorphologic and Histomorphometric Assessment in Dogs

    OpenAIRE

    Mansour Rismanchian; Sayed Hamid Raji; Danesh Teimori Rik; Sayed Mohammad Razavi; Navid Khalighinejad; Hossein Goroohi; Hamid Badrian

    2012-01-01

    Aim. The aim of this study was histomorphologic and histomorphometric evaluation of peri-screw bone after immediate orthodontic and orthopedic forces and comparing them with a control group. Materials and Methods. 18 dual-top miniscrews were inserted in the premolar region of three Iranian dogs. Screws were divided into three groups: (1) the first group undergoing immediate orthodontic force of 300?cN, (2) the second group undergoing immediate orthopedic force of 600?cN and (3) a control grou...

  15. Evolution of Class III treatment in orthodontics.

    Science.gov (United States)

    Ngan, Peter; Moon, Won

    2015-07-01

    Angle, Tweed, and Moyers classified Class III malocclusions into 3 types: pseudo, dentoalveolar, and skeletal. Clinicians have been trying to identify the best timing to intercept a Class III malocclusion that develops as early as the deciduous dentition. With microimplants as skeletal anchorage, orthopedic growth modification became more effective, and it also increased the scope of camouflage orthodontic treatment for patients who were not eligible for orthognathic surgery. However, orthodontic treatment combined with orthognathic surgery remains the only option for patients with a severe skeletal Class III malocclusion or a craniofacial anomaly. Distraction osteogenesis can now be performed intraorally at an earlier age. The surgery-first approach can minimize the length of time that the malocclusion needs to worsen before orthognathic surgery. Finally, the use of computed tomography scans for 3-dimensional diagnosis and treatment planning together with advances in imaging technology can improve the accuracy of surgical movements and the esthetic outcomes for these patients. PMID:26124025

  16. Root Resorption in Orthodontics: Literature Review

    Directory of Open Access Journals (Sweden)

    María Alexandra Lozano-Chourio

    2009-12-01

    Full Text Available This article is a literature review about external root resorption and the biological and mechanical factors that predispose its appearance in orthodontic patients. Genetic, systemic and pharmacological factors, chronological and dental age, nutritional status, gender, race, habits, tooth morphology, size and number, resorptions and dental trauma previous to periapical infections, occlusal factors and specific vulnerability to resorption are described. Among mechanical factors, the type of appliances, the type of movement, duration of forces, and duration of treatment are included. Since external root resorption is considered an undesirable side effect associated with orthodontic movement, it is responsibility of the orthodontist to be aware of all these risk factors for external root resorption, for its timely prevention or interception.

  17. Computerized analysis of the smile in Orthodontics

    Directory of Open Access Journals (Sweden)

    Luiz Vicente de Moura LOPES

    2006-05-01

    Full Text Available In most cases the search for orthodontic treatment is related withesthetics cause. Nowadays, a beautiful smile is extremely importantfor the society. Establishing elements for diagnosis and planning,looking at a harmonious and well-balanced smile became an obligation at dentistry offices. The esthetics is evaluated by the outline of the bone tissues and its relation with the soft tissues. A good way to get this evaluation is using photographs. The purpose of this research was to analyze computer standard pictures of the maximum smile, as complement to the orthodontic documentation to help not only in the diagnostic and planning but also in the valuation of obtained results. Standard pictures of the maximum smile were obtained in the natural position of the head. Linear,angular and proportional measures were evaluated through the computerized program (CEFX2001 – CDT. The sample consisted of 28 patients, white, male, age between 19 and 25 years old, with Class I occlusion and no previous orthodontic treatment. The values of the descriptive statistics and error analysis were obtained. The results were compared with the values found in the literature, and the values found at a study using the same computerized program CEFX2001 – CDT, but with female patients. The final results were similar to the values found in the literature and the values found in a study using the same computerized program CEFX2001 – CDT,but with female patients.

  18. GLASS TRANSITION AND DEGREE OF CONVERSION OF A LIGHT-CURED ORTHODONTIC COMPOSITE

    OpenAIRE

    Sostena, Michela M. D. S.; Nogueira, Renata A.; Grandini, Carlos R.; João Carlos Silos Moraes

    2009-01-01

    OBJECTIVE: This study evaluated the glass transition temperature (Tg) and degree of conversion (DC) of a light-cured (Fill Magic) versus a chemically cured (Concise) orthodontic composite. MATERIAL AND METHODS: Anelastic relaxation spectroscopy was used for the first time to determine the Tg of a dental composite, while the DC was evaluated by infrared spectroscopy. The light-cured composite specimens were irradiated with a commercial LED light-curing unit using different exposure times (40, ...

  19. Eficacia del JAL 90458 sobre el recrecimiento de placa en pacientes con aparatología fija multibrackets / Efficacy of JAL 90458 in the regrowth of plaque in patients with orthodontic braces

    Scientific Electronic Library Online (English)

    P.C., Claudet Angulo; J.J., Alió Sanz; E.M., Ramírez Mingorance; C., Iglesias Conde; F.J., Manso Platero.

    2013-10-01

    Full Text Available Introducción. El objetivo fue evaluar la eficacia del JAL 90458 sobre el recrecimiento de placa en pacientes con aparatología fija "multibrackets". Material y métodos. Participaron 16 sujetos (11 mujeres y 5 hombres) entre 12 a 39 años de edad. El estudio fue realizado bajo condiciones de un ensayo [...] clínico, aleatorizado, doble ciego y paralelo de grupos balanceados usando un diseño de recrecimiento de placa. Los sujetos recibieron una profilaxis oral y suspendieron toda medida de higiene oral por los siguientes 4 días, usando sólo el gel asignado. Se evaluó el Índice de placa de Quigley-Hein modificado por Turesky (IPQH-T), el Índice de placa bracket (IPb) y el Índice de Sangrado al Sondaje (ISS). Para el análisis de datos se utilizó el test de la t de Student para muestras independientes, el test exacto de Fisher y el coeficiente de correlación de Pearson. Resultados. Se obtuvieron diferencias estadísticamente significativa entre el JAL 90458 y el gel control en el IPQH-T (2,52±0,57 vs 1,78±0,79, p Abstract in english Introduction. The objective was test the efficacy of JAL 90458 on the regrowth of plaque in patients with orthodontic braces. Material and methods. A total of 16 subjects (11 women and 5 men) between the ages of 12 and 39 took part in this study. The study was conducted under clinical trial conditio [...] ns, double blind, parallel and randomized in balanced groups using a plaque regrowth design. The subjects had a professional teeth-cleaning and were instructed to not use any kind of oral hygiene measures for the next four days, using only the gel that had been assigned to them. We took into account the following parameters: the Quigley - Hein plaque index, modified by Turesky (QHPI-T), Plaque-Bracket Index (PIb) and the Bleeding on Probing Index (BOP). Analysis of the data was done using a Student´s t-test, Fisher´s exact test and Pearson´s correlation coefficient. Results. Statistically significant differences between the JAL 90458 group and the control gel group were obtained in the QHPI-T (2.52±0.57 vs 1.78±0.79, p

  20. Periodontal Intervention in Speedy Orthodontics-A Case Report.

    Science.gov (United States)

    Kumar, Snehi; Srivastava, Amitabh; Sharma, Ashish; Garg, Aarti; Kumar, Surubhi

    2016-01-01

    The use of orthodontic treatment in adult patients is becoming more common and these patients have more specific objectives and concerns related to facial and dental aesthetics, specially regarding duration of treatment. Dentists are on the lookout for techniques for increased efficiency in orthodontic treatment. Alveolar Corticotomy-assisted orthodontic treatment is a recent orthodontic technique that is recently gaining wide acceptance and is recorded as effective means of accelerating orthodontic treatment. A 17-year-old female patient was undergoing orthodontic treatment for the past one year but during her space closure, a visual examination confirmed a buccal thickening that was encountered in the buccal plate between premolars and canine. Periodontal intervention involved elective alveolar decortication in the form of dots performed around the teeth that were to be moved. This was carried out to induce a state of increased tissue turnover and a transient osteopenia, which further helps in faster rate of orthodontic tooth movement. Its main advantages are reduction of treatment time and post-orthodontic stability. PMID:26894189

  1. Orthodontic traction of impacted canine using magnet: a case report

    OpenAIRE

    Li, Larry CF; Wong, Ricky WK; King, Nigel M

    2008-01-01

    ABSTRACT: A 15 year and 1 month old Chinese female with palatally impacted upper left canine was successfully treated with an upper removable appliance with a magnet incorporated to provide orthodontic traction force. This case report indicates the possibility of using magnetic force as a safe, effective and comfortable way for orthodontic traction.

  2. The management of traumatic ankylosis during orthodontics: a case report.

    LENUS (Irish Health Repository)

    McNamara, T G

    2000-01-01

    Dental ankylosis may be a significant complication in orthodontic clinical practice. This case report describes the management of a malocclusion, complicated by an ankylosed maxillary central incisor, which arose during orthodontic treatment, following an acute traumatic injury. The use of the ankylosed incisor in successfully managing the significant Class II division 1 malocclusion is described.

  3. Orthodontics Without Braces and Wires!! ....... A New Paradigm.

    Directory of Open Access Journals (Sweden)

    Vasu Murthy S

    2011-07-01

    Full Text Available The very need of orthodontic treatment by a majority of patients is often for reasons of enhancement or improvement in dental alignment and facial esthetics. Reluctance for use of labial fixed metallic appliances is due to poor esthetics and fear of pain. Clear plastic aligners offer an excellent alternative to esthetic orthodontic treatment especially for young adults in their permanent dentition.

  4. Orthodontic Anchorage Implants: State-of-the-art

    DEFF Research Database (Denmark)

    Melsen, Birte

    2007-01-01

    The limits of an orthodontic treatment are often set by the lack of suitable anchorage. The mini-implant is used where conventional anchorage cannot be applied and not as a replacement for conventional anchorage. In patients with lack of teeth and reduced periodontium, skeletal anchorage allows the...... will improve the reconstruction possibilities. The mini-implant has widened the orthodontic possibilities....

  5. Paradigm shifts in orthodontic treatment with mini-implant anchorage

    Directory of Open Access Journals (Sweden)

    Johnny Joung-Lin Liaw

    2015-01-01

    Full Text Available After the applications of mini-implant anchorage, the envelope of orthodontic treatment was expanded and some treatment modes were changed because of more predictable tooth movement with empowered anchorage. The author tried to share his experience of TADs applications for clarifying the paradigm shifts of orthodontic treatment assisted with the mini-implant anchorage.

  6. Transversal changes in dental arches from non-extraction treatment with self ligating brackets

    Scientific Electronic Library Online (English)

    Liliana Avila, Maltagliati; Yasushi Inoue, Myiahira; Liana, Fattori; Leopoldino, Capelozza Filho; Mauricio, Cardoso.

    2013-06-01

    Full Text Available OBJETIVO: o presente estudo teve por objetivo avaliar, em modelos de gesso, as alterações dimensionais transversais das arcadas dentárias, decorrentes do tratamento ortodôntico sem extração, com braquetes autoligáveis. MÉTODOS: a amostra constou de 29 pacientes que apresentavam má oclusão de Classe [...] I, com apinhamento superior e inferior mínimo de 4mm, que foram tratados unicamente com aparelho fixo, sem desgastes, extração ou distalização dentária. Os modelos de gesso foram obtidos antes e ao final do tratamento. CONCLUSÃO: os resultados indicaram que as maiores alterações transversais ocorreram na região dos pré-molares, tanto dos primeiros como dos segundos, e tanto na maxila como na mandíbula. A distância intercaninos teve aumento, em média, de 0,75mm na arcada superior, e de 1,96mm na inferior. Os molares também demonstraram tendência de aumento das dimensões transversais, porém em menor intensidade que os pré-molares. Todas as medidas denotaram diferença estatisticamente significativa, com exceção dos segundos molares superiores. Abstract in english OBJECTIVE: The present study aimed at analyzing, with the use of dental casts, the transverse changes of the upper and lower dental arches, after non-extraction orthodontic treatment, with self-ligating brackets. METHODS: The sample comprised 29 patients, all presenting Class I malocclusion with upp [...] er and lower crowding of at least 4 mm and treated only with a fixed appliance, without stripping, extraction or distalization. The dental casts were obtained before and after leveling with 0.019 x 0.025-in stainless steel archwires. CONCLUSION: The results indicated that the majority of transverse changes occurred at the premolar areas, both the first and the second, as well as on the upper and lower dental arches. The intercanine distance increased 0.75 mm, on average, in the upper arch and 1.96 mm in the lower arch. The molars also demonstrated a tendency towards an increase in their transverse dimension, however, at a lower intensity comparing to premolars. All measurements presented statistically significant differences with the exception of the maxillary second molars.

  7. Assessment of Bond Strength between Metal Brackets and Non-Glazed Ceramic in Different Surface Treatment Methods

    Directory of Open Access Journals (Sweden)

    I. Harririan

    2010-06-01

    Full Text Available Objective: The aim of this study was to evaluate the bond strength between metal brackets and non-glazed ceramic with three different surface treatment methods.Materials and Methods: Forty-two non-glazed ceramic disks were assigned into three groups. Group I and II specimens were etched with 9.5% hydrofluoric acid. Subsequently in group I, silane and adhesive were applied and in group II, bonding agent was used only.In group III, specimens were treated with 35% phosphoric acid and then silane and adhesive were applied. Brackets were bonded with light-cured composites. The specimens were stored in water in room temperature for 24 hours and then thermocycled 500 times between 5°C and 55°C.Results: The difference of tensile bond strength between groups I and III was not significant(P=0.999. However, the tensile bond strength of group II was significantly lower than groups I, and III (P<0.001. The adhesive remnant index scores between the threegroups had statistically significant differences (P<0.001.Conclusion: With the application of scotch bond multi-purpose plus adhesive, we can use phosphoric acid instead of hydrofluoric acid for bonding brackets to non-glazed ceramic restorations.

  8. Comparison of rate of maxillary canine movement with or without modified corticotomy facilitated orthodontic treatment: A prospective clinical trial

    Directory of Open Access Journals (Sweden)

    Harshal N Suryavanshi

    2015-01-01

    Full Text Available Background and Objectives: The average orthodontic treatment time for extraction therapy is 31 months. One of the main disadvantages of orthodontic treatment is time. Alveolar corticotomies have been used in conjunction with orthodontics to reduce the treatment time by increasing the rate of tooth movement. Concerns about the possible risks of corticotomy procedure have led to the modification of this technique. Germeη et al. reported a case treated by their modified corticotomy technique and noted reduced treatment time without any adverse effects on the periodontium and the vitality of teeth with their new conservative corticotomy technique. This study was undertaken to clinically evaluate the efficacy of the aforesaid technique. Materials and Methods: A split-mouth study design was carried out to compare the rate of maxillary canine movement with and without modified corticotomy facilitated orthodontic treatment in 10 patients requiring maxillary first premolar extractions. The modified corticotomy procedure was performed on the maxillary arch unilaterally. The upper arch was immediately activated bilaterally after surgical procedure using equal orthodontic forces for retraction of the maxillary canines. The amount of tooth movement was recorded at an interval of every month till the completion of canine retraction. The rate of canine movement on experimental and control site was compared. The patients were followed for 6 months to check the occurrence of undesired effects such as root resorption, periodontal damage and loss of vitality of teeth on the experimental side. Results: Higher mean velocity was observed in canines with modified corticotomy facilitated retraction compared to conventionally retracted canines; with the difference in mean velocity between the two groups was found to be clinically significant as well as statistically significant (P < 0.001. Interpretation and Conclusion: The results suggested that modified corticotomy technique serves as an effective and safe way to accelerate orthodontic tooth movement, without adversely affecting the periodontium, root resorption, and the vitality of the teeth, as concluded by clinical and radiographic examination.

  9. Double bracket dissipation in kinetic theory for particles with anisotropic interactions

    OpenAIRE

    Holm, Darryl D.; Putkaradze, Vakhtang; Tronci, Cesare

    2007-01-01

    We derive equations of motion for the dynamics of anisotropic particles directly from the dissipative Vlasov kinetic equations, with the dissipation given by the double bracket approach (Double Bracket Vlasov, or DBV). The moments of the DBV equation lead to a nonlocal form of Darcy's law for the mass density. Next, kinetic equations for particles with anisotropic interaction are considered and also cast into the DBV form. The moment dynamics for these double bracket kinetic...

  10. Actual versus theoretical torsional play in conventional and self-ligating bracket systems

    DEFF Research Database (Denmark)

    Dalstra, Michel; Eriksen, Henrik

    2015-01-01

    Abstract Objective: The aim of this study was to assess the amount of torsional play in 32 commercially available self-ligating and conventional 0·018-inch and 0·022-inch bracket systems in relation to 0·017×0·022-inch and 0·019×0·025-inch stainless steel wires, respectively, and compare the results with the theoretical amount of play for the given bracket/wire combinations. Methods: Torque moments were measured in a mechanical force testing system by twisting straight pieces of stainless steel wire seated in the bracket slot in increments of 0·5° until a full torsional expression was registered. Five upper central incisor brackets from each of the 32 different bracket systems were selected for the study. Results: The result from the laboratory testing clearly showed that wire/slot play was larger than anticipated from the nominal values, especially regarding the 0·022-inch brackets and particularly in relation to the passive self-ligating brackets. The play ranged from 19·8 to 36·1° of play for the most imprecise bracket system. Conclusions: The result does not favour the use of self-ligating brackets when focussing on torque control. The actual play is larger due to oversized slots and the inability of self-ligation brackets to press the archwire into the bottom of the slot. In conventional brackets, the initial torque moment is generated by the steel ligatures pressing the arch wire against the bottom of the slot. The oversize of the slot is thus less critical in relation to the conventional than in relation to the passive self-ligation bracket.

  11. Cariogram caries risk profiles in adolescent orthodontic patients with and without some salivary variables

    DEFF Research Database (Denmark)

    Petsi, Georgia; Gizani, Sotiria; Twetman, Svante; Kavvadia, Katerina

    2014-01-01

    OBJECTIVE: To compare the Cariogram caries risk profiles with and without salivary buffer capacity and mutans streptococci (MS) counts in adolescents with fixed orthodontic appliances. MATERIALS AND METHODS: The sample consisted of 90 healthy Greek adolescents who were undergoing orthodontic...... treatment. The Cariogram risk model was applied through a questionnaire and clinical and salivary examinations. The actual chance of avoiding new caries was calculated, and participants were categorized into three groups (0-40% ?=? high caries risk, 41-60% ?=? medium caries risk, and 61-100% ?=? low caries...... to the medium risk category when MS counts were excluded. The difference between the nine-item Cariogram and the MS-reduced version, however, was not statistically significant (P ?=? .07). CONCLUSIONS: The Cariogram model may be used both with and without salivary tests for risk grouping in...

  12. Multiplicative structure of Kauffman bracket skein module quantizations

    OpenAIRE

    Bullock, Doug; Przytycki, Jozef H.

    1999-01-01

    We describe, for a few small examples, the Kauffman bracket skein algebra of a surface crossed with an interval. If the surface is a punctured torus the result is a quantization of the symmetric algebra in three variables (and an algebra closely related to a cyclic quantization of $U(so_3$). For a torus without boundary we obtain a quantization of "the symmetric homologies" of a torus (equivalently, the coordinate ring of the $SL_2(C)$-character variety of $Z \\oplus Z$). Presentations are als...

  13. Maslov indices, Poisson brackets, and singular differential forms

    Science.gov (United States)

    Esterlis, I.; Haggard, H. M.; Hedeman, A.; Littlejohn, R. G.

    2014-06-01

    Maslov indices are integers that appear in semiclassical wave functions and quantization conditions. They are often notoriously difficult to compute. We present methods of computing the Maslov index that rely only on typically elementary Poisson brackets and simple linear algebra. We also present a singular differential form, whose integral along a curve gives the Maslov index of that curve. The form is closed but not exact, and transforms by an exact differential under canonical transformations. We illustrate the method with the 6j-symbol, which is important in angular-momentum theory and in quantum gravity.

  14. Comparison surface characteristics and chemical composition of conventional metallic and Nickel-Free brackets

    Scientific Electronic Library Online (English)

    Ricardo Lima, Shintcovsk; Luegya Amorim Henriques, Knop; Luiz Gonzaga, Gandini Jr; Lidia Parsekian, Martins; Aline Segatto, Pires.

    Full Text Available This study aims at comparing conventional and nickel-free metal bracket surface characteristics with elemental composition by scanning electron microscopy (SEM), using energy dispersive spectroscopy (EDS). The sample consisted of 40 lower incisor brackets divided into four groups: ABZ = conventional [...] brackets, Kirium Abzil 3M® (n = 10); RL = conventional brackets, Roth Light Morelli® (n = 10); NF = nickel-free brackets, Nickel-Free Morelli® (n = 10); and RM = nickel-free brackets, Roth Max Morelli® (n = 10). Qualitative evaluation of the bracket surface was performed using SEM, whereby surface features were described and compared. The elemental composition was analyzed by EDS. According to surface analysis, groups ABZ and RL showed a homogeneous surface, with better finishing, whereas the surfaces in groups NF and RM were rougher. The chemical components with the highest percentage were Fe, Cr and C. Groups NF and MR showed no nickel in their composition. In conclusion, the bracket surface of the ABZ and RL groups was more homogeneous, with grooves and pores, whereas the surfaces in groups NF and RM showed numerous flaws, cracks, pores and grooves. The chemical composition analysis confirmed that the nickel-free brackets had no Ni in their composition, as confirmed by the manufacturer’s specifications, and were therefore safe to use in patients with a medical history of allergy to this metal.

  15. Geometry of Vlasov kinetic moments: A bosonic Fock space for the symmetric Schouten bracket

    International Nuclear Information System (INIS)

    The dynamics of Vlasov kinetic moments is shown to be Lie-Poisson on the dual Lie algebra of symmetric contravariant tensor fields. The corresponding Lie bracket is identified with the symmetric Schouten bracket and the moment Lie algebra is related with a bundle of bosonic Fock spaces, where creation and annihilation operators are used to construct the cold plasma closure. Kinetic moments are also shown to define a momentum map, which is infinitesimally equivariant. This momentum map is the dual of a Lie algebra homomorphism, defined through the Schouten bracket. Finally the moment Lie-Poisson bracket is extended to anisotropic interactions

  16. Dirac's and Generalized Faddeev-Jackiw brackets for Einstein's theory in G $\\rightarrow 0$ limit

    CERN Document Server

    Escalante, Alberto

    2015-01-01

    In this paper the Dirac and Faddeev-Jackiw formulation for Einstein's theory in $G \\rightarrow 0$ limit is performed; the fundamental Dirac's and Faddeev-Jackiw brackets for the theory are obtained. First, the Dirac brackets are constructed by eliminating the second class constraints remaining the first class ones, then we fix the gauge and we convert the first class constraints in second class constraints and the new fundamental Dirac's brackets are computed. Alternatively, we reproduce all relevant Dirac's results by means of the symplectic method. We identify the Faddeev-Jackiw constraints and we prove that the Dirac and the Faddeev-Jackiw brackets coincide to each other.

  17. THE EFFECTS OF FIXED ORTHODONTIC TREATMENT PERIOD ON WHITE SPOT LESION PREVALENCE AND DMFT INDEX-Sabit Ortodontik Tedavi Süresinin Beyaz Nokta Lezyonu Olu?um S?kl??? ve DMFT ?ndeksi Üzerine Etkileri

    OpenAIRE

    KARABEK?RO?LU, Said; ?LER?, Zehra; KAHRAMAN, Fatma Betül; Ünlü, Nimet

    2014-01-01

    ABSTRACTPurpose: The purpose of this study was to assess the effects of fixed orthodontic treatment duration on DMFT (D: decay, F: filling and M: missing teeth) index and white spot lesion (WSL) formation.Materials and Methods: Eighty four patients (45 females and 39 males, 13-18 years old, mean age: 14.7±0.8) who were undergoing fixed orthodontic treatment were invited to participate in this study. All patients were treated with a 0.018 inch slot MBT fixed orthodontic appliances. An examiner...

  18. Evaluation of the changes of interleukin- 6 level in gingival cervical fluid (GCF during orthodontic movements

    Directory of Open Access Journals (Sweden)

    Safavi SMR

    2007-06-01

    Full Text Available Background and Aim: In recent years, different substances have been considered in gingival cervical fluid (GCF as diagnostic markers due to the evaluation of biologic events and biochemical process related to bone turnover during orthodontic movements. IL-6 concentration increases in GCF during the first week after force loading. The aim of this study was to investigate the levels of IL-6 in GCF during orthodontic movements.Materials and Methods: Fourteen orthodontic patients (9 females and 5 males, mean age 15.1±2.5 years with "nCl I malocclusion needing first bicuspid extraction participated in this clinical trial. In each patient one maxillary canine was distalized (DC with a NiTi push coil spring. The contra-lateral canine (CC was included in the orthodontic appliance but was not subjected to the orthodontic force  and one of the mandibular canines was used as control with no orthodontic appliance (Antagonist canine: AC. The concentration of IL-6 was evaluated at the baseline and 14th and 28th days after intervention. GCF was taken with periopapers from both mesial and distal sides of tooth before appliance activation, on the 14th and 28th days. Concentration of IL-6 in DC, CC, and AC detected by ELISA reader was compared by repeated measure ANOVA and LSD multiple comparison, P<0.05 was considered statistically significant.Results: Although the inflammatory gingival indices increased in both DC and CC teeth but it was not significant. The amount of IL-6 in GCF increased on day 14th in DC teeth in comparison with AC and CC teeth. In addition, the concentration of IL-6 in DC teeth was significantly greater than the 1st and 28th days. The maximum concentration of IL-6 was detected in both pressure and tension sides of DCs at T14. At T28, although the IL-6 levels were significantly higher than baseline levels but, it was significantly less than T14.Conclusion: The results of this study support the hypothesis that mechanical stimuli cause an inflammatory reaction within the periodontal tissues.