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Adhesives for orthodontic bracket bonding  

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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.

Déborah Daniella Diniz Fonseca

2010-04-01

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Effects of fluoride release from orthodontic bonding materials on nanomechanical properties of the enamel around orthodontic brackets  

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Background: The aim of the present study is to evaluate the effects of a fluoride-releasing composite resin bonding material on reducing enamel demineralization underneath and around orthodontic brackets and compare that with a conventional adhesive system. Materials and Methods: Buccal surfaces of 10 intact extracted premolar teeth were divided into two parts with nail varnish and stainless steel brackets were randomly bonded by two resin composite systems: (Transbond XT) and (Transbond XT plus Color Change) (3M, Unitek, Monrovia, CA, USA) on two sides of the teeth and then samples were placed in a demineralization solution. It is claimed that the second system has the ability of fluoride release. Elastic modulus and hardness of enamel were measured with nanoindentation test in 6 depths in 1-36 ?m from the enamel surface and in 7 regions: Control (intact enamel surface), underneath the brackets and also 50 and 100 ?m from the brackets edge. These nanomechanical features were evaluated in different regions and depths using analysis of variance and paired t-test (P < 0.05). Results: Considerable difference can be seen in different depths and regions in terms of hardness and elastic modulus. The region under the bracket with fluoridated adhesive shows similar results with intact enamel, whereas these parameters in fluoride less side show a significant reduction (P < 0.05). Conclusion: Results show that use of resin composite bonding system with the ability of fluoride release for bracket bonding, may reduce demineralization of enamel around brackets during orthodontic treatment. PMID:24688563

Raji, Seyed Hamid; Banimostafaee, Hamed; Hajizadeh, Fatemeh

2014-01-01

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The use of Ormocer as an alternative material for bonding orthodontic brackets.  

Science.gov (United States)

As new adhesives, composite resins, and bonding techniques were introduced, orthodontists adopted some of these innovations and added them to their armamentarium. The purpose of this study was to compare the shear bond strength (SBS) of two adhesive materials; one with an organically modified ceramic matrix, Admira (Voco, Cuxhaven, Germany) and another that contains the traditional Bis GMA matrix namely Transbond XT (3M Unitek, Monrovia, Calif). The new materials have a lower wear rate and are more biocompatible than traditional composites. Forty molar teeth were randomly divided into two groups: 20 teeth bonded with the Transbond adhesive system and the other 20 teeth with the Admira bonding system. Student's t-test was used to compare the SBS of the two adhesives. Significance was predetermined at P < or = .05. The results of the t-test comparisons (t = 0.489) of the SBS indicated that there was no significant (P = .628) difference between the two adhesives tested. The mean SBS for Admira was 5.1 +/- 3.3 MPa and that for Transbond XT was 4.6 +/- 3.2 MPa. It was concluded that the new material, Ormocer, which is an organically modified ceramic restorative material can potentially have orthodontic applications if available in a more flowable paste. These new materials are more biocompatible and have lower wear rate including bonding orthodontic brackets to teeth. PMID:15747824

Ajlouni, Raed; Bishara, Samir E; Soliman, Manal M; Oonsombat, Charuphan; Laffoon, John F; Warren, John

2005-01-01

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A stainless steel bracket for orthodontic application.  

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Aesthetics has become an essential element when choosing orthodontic fixed appliances. Most metallic brackets used in orthodontic therapy are made from stainless steel (SS) with the appropriate physical properties and good corrosion resistance, and are available as types 304, 316 and 17-4 PH SS. However, localized corrosion of these materials can frequently occur in the oral environment. This study was undertaken to evaluate the accuracy of sizing, microstructure, hardness, corrosion resistance, frictional resistance and cytotoxicity of commercially available Mini-diamond (S17400), Archist (S30403) and experimentally manufactured SR-50A (S32050) brackets. The size accuracy of Mini-diamond was the highest at all locations except for the external horizontal width of the tie wing (P < 0.05). Micrographs of the Mini-diamond and Archist showed precipitates in the grains and around their boundaries. SR-50A showed the only austenitic phase and the highest polarization resistance of the tested samples. SR-50A also had the highest corrosion resistance [SR-50A, Mini-diamond and Archist were 0.9 x 10(-3), 3.7 x 10(-3), and 7.4 x 10(-3) mm per year (mpy), respectively], in the artificial saliva. The frictional force of SR-50A decreased over time, but that of Mini-diamond and Archist increased. Therefore, SR-50A is believed to have better frictional properties to orthodontic wire than Mini-diamond and Archist. Cytotoxic results showed that the response index of SR-50A was 0/1 (mild), Mini-diamond 1/1 (mild+), and Archist 1/2 (mild+). SR-50A showed greater biocompatibility than either Mini-diamond or Archist. It is concluded that the SR-50A bracket has good frictional property, corrosion resistance and biocompatibility with a lower probability of allergic reaction, compared with conventionally used SS brackets. PMID:15947222

Oh, Keun-Taek; Choo, Sung-Uk; Kim, Kwang-Mahn; Kim, Kyoung-Nam

2005-06-01

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Biodegradation of the orthodontic bracket system.  

Science.gov (United States)

Corrosion of the orthodontic appliance may occur in vivo with time. Electrochemical breakdown of corrosion-resistant high nickel and titanium wire can also occur. The use of recycled brackets could possibly accelerate the corrosion process. New and recycled brackets were evaluated in vitro in an artificial saliva system. The results indicated that different brands of new brackets have differences in corrosion behavior. In addition, recycling by the three commercial processes tested increased the liability of brackets to undergo corrosion. Superior behavior was noted for two types of bracket bases. Bracket corrosion may be assessed by a simple in vitro test. PMID:3463194

Maijer, R; Smith, D C

1986-09-01

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In Vitro Effects of Two Topical Varnish Materials and Er:YAG Laser Irradiation on Enamel Demineralization around Orthodontic Brackets  

Science.gov (United States)

The aim of this in vitro was to evaluate the effects of tricalcium phosphate (TCP) and amorphous calcium phosphate (ACP) containing varnish materials and Er:YAG laser irradiation on enamel demineralization around orthodontic brackets. Forty extracted human premolar teeth were randomly divided into four treatment groups (i.e., 10 in each group): (1) 5% NaF-ACP varnish, (2) 5% NaF-TCP varnish, (3) Er:YAG laser, and (4) control (no treatment). Er:YAG laser was operated at a wavelength of 2.94??m and the energy output was 80?mJ per pulse; a pulse duration of 200??sec and and a frequency of 2?Hz were used with water cooling. All samples were then put into pH cycles. Surface microhardness values and representative SEM images were assessed. Surface microhardness values were evaluated using Kruskal-Wallis and Mann-Whitney U tests. The results revealed that demineralization was significantly lower in the TCP and ACP varnish groups, whereas mean surface microhardness values of the TCP varnish were found higher than the ACP (P < 0.05). TCP and ACP varnish materials were found effective for reducing enamel demineralization around orthodontic brackets. Use of Er:YAG laser irradiation as described in this study for inhibition of demineralization was found not satisfactory. PMID:24987734

Sungurtekin Ekci, Elif; Sandalli, Nuket

2014-01-01

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Soportes de autoligado en ortodoncia / Orthodontic brackets  

Scientific Electronic Library Online (English)

Full Text Available SciELO Cuba | Language: Spanish Abstract in spanish Fundamento: el sistema de ligado del arco al soporte debe ser seguro, fuerte, rápido, confortable para el paciente, fácil de usar y producir poca fricción. Objetivo: argumentar el manejo de las técnicas fijas con el uso de los soportes de autoligado. Conclusiones: los soportes de autoligado constitu [...] yen una opción novedosa en ortodoncia, pero en Cuba se han utilizado poco. Se clasifican en pasivos y activos. El sistema Damon, Vision LP y Time son los más utilizados entre los pasivos y el Speed e In Ovation entre los activos. Se describen cuatro fases de tratamiento para usar la técnica con este tipo de soportes y a pesar de su alto costo, es más ventajosa que las técnicas precedentes. Abstract in english Background: the system bound to the orthodontic bracket arch must be safe, strong, rapid and comfortable for the patient, easy to use and must provoke little friction. Objective: to argue about the management of fixed techniques with the use of brackets. Conclusions: brackets constitute a newfangled [...] option in orthodontics, but in Cuba it has been rarely used. They are classified into passive and active. Damon system, Vision LP and Time are the mostly used among the passive ones and the Speed and In Ovation among the active ones. Four phases of treatment are described to use the technique of these orthodontic brackets and in spite of its high cost; it is more advantageous than the previous techniques.

Lizandro Michel, Pérez García; Eduardo, Reytor Saavedra.

2013-04-01

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Soportes de autoligado en ortodoncia / Orthodontic brackets  

Scientific Electronic Library Online (English)

Full Text Available SciELO Cuba | Language: Spanish Abstract in spanish Fundamento: el sistema de ligado del arco al soporte debe ser seguro, fuerte, rápido, confortable para el paciente, fácil de usar y producir poca fricción. Objetivo: argumentar el manejo de las técnicas fijas con el uso de los soportes de autoligado. Conclusiones: los soportes de autoligado constitu [...] yen una opción novedosa en ortodoncia, pero en Cuba se han utilizado poco. Se clasifican en pasivos y activos. El sistema Damon, Vision LP y Time son los más utilizados entre los pasivos y el Speed e In Ovation entre los activos. Se describen cuatro fases de tratamiento para usar la técnica con este tipo de soportes y a pesar de su alto costo, es más ventajosa que las técnicas precedentes. Abstract in english Background: the system bound to the orthodontic bracket arch must be safe, strong, rapid and comfortable for the patient, easy to use and must provoke little friction. Objective: to argue about the management of fixed techniques with the use of brackets. Conclusions: brackets constitute a newfangled [...] option in orthodontics, but in Cuba it has been rarely used. They are classified into passive and active. Damon system, Vision LP and Time are the mostly used among the passive ones and the Speed and In Ovation among the active ones. Four phases of treatment are described to use the technique of these orthodontic brackets and in spite of its high cost; it is more advantageous than the previous techniques.

Lizandro Michel, Pérez García; Eduardo, Reytor Saavedra.

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

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Full Text Available SciELO Brazil | Language: English Abstract in english 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.

Alexandra Ioana, Holst; Stefan, Holst; Ursula, Hirschfelder; Volker Von, Seckendorff.

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

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english 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.

Alexandra Ioana, Holst; Stefan, Holst; Ursula, Hirschfelder; Volker Von, Seckendorff.

2012-08-01

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

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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.

Alexandra Ioana Holst

2012-08-01

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Effect of bonding material, etching time and silane on the bond strength of metallic orthodontic brackets to ceramic  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese O objetivo neste estudo foi avaliar a resistência de união de bráquetes a cerâmica feldspática com diferentes tempos de condicionamento ácido, materiais de união, com ou sem aplicação do silano. Cilindros de cerâmica feldspática foram condicionados com ácido fluorídrico 10% por 20 ou 60 s. Para cada [...] tempo de condicionamento, metade dos cilindros recebeu duas camadas de silano. Bráquetes metálicos foram fixados aos cilindros utilizando Transbond XT (3M Unitek) ou Fuji Ortho LC (GC). A fotoativação foi realizada com tempo de exposição total de 40 s utilizando LED UltraLume 5. O ensaio de resistência ao cisalhamento foi realizado após 24 h de armazenagem. Os dados foram submetidos à Análise de Variância a três fatores e teste de Tukey (?=0,05). O Índice de Remanescente Adesivo (IRA) foi utilizado para avaliar a quantidade de adesivo remanescente na superfície cerâmica com magnificação de 8×. Os espécimes condicionados por 60 s apresentaram maior resistência de união comparado com 20 s. A aplicação do silano foi efetiva no aumento da resistência de união ao cisalhamento de bráquetes com a cerâmica para ambos os materiais. O Transbond XT mostrou resistência de união significativamente maior que Fuji Orth LC. O IRA mostrou predominância de escore 0 (ausência de resina na superfície cerâmica) para todos os grupos, com aumento de escores 1, 2 e 3 (aumento da presença de resina na superfície cerâmica) para o tempo de condicionamento de 60 s. Em conclusão, o tempo de condicionamento de 60 s, aplicação de silano e resina Transbond XT melhoraram significativamente a resistência de união ao cisalhamento de bráquetes a cerâmica feldspática. Abstract in english The purpose of this study was to evaluate the bond strength of metallic orthodontic brackets to feldspathic ceramic with different etching times, bonding materials and with or without silane application. Cylinders of feldspathic ceramic were etched with 10% hydrofluoric acid for 20 or 60 s. For each [...] etching time, half of the cylinders received two layers of silane. Metallic brackets were bonded to the cylinders using Transbond XT (3M Unitek) or Fuji Ortho LC (GC). Light-activation was carried out with total exposure time of 40 s using UltraLume 5. Shear bond strength testing was performed after 24 h storage. Data were submitted to three-way ANOVA and Tukey's test (?=0.05). The adhesive remnant index (ARI) was used to evaluate the amount of adhesive remaining on the ceramic surface at ×8 magnification. Specimens etched for 60 s had significantly higher bond strength compared with 20 s. The application of silane was efficient in increasing the shear bond strength between ceramic and both fixed materials. Transbond XT showed significantly higher (p

Ana Rosa, Costa; Américo Bortolazzo, Correr; Regina Maria, Puppin-Rontani; Silvia Amélia, Vedovello; Heloísa Cristina, Valdrighi; Lourenço, Correr-Sobrinho; Mário, Vedovello Filho.

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Shear bond strength of orthodontic brackets bonded with glass ionomer cement  

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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.

Miti? Vladimir

2009-01-01

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

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english 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.

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

2014-06-01

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Metallurgical characterization, galvanic corrosion, and ionic release of orthodontic brackets coupled with Ni-Ti archwires.  

Science.gov (United States)

In orthodontics, a combination of metallic alloys is placed into the oral cavity during medical treatment and thus the corrosion resistance and ionic release of these appliances is of vital importance. The aim of this study is to investigate the elemental composition, microstructure, hardness, corrosion properties, and ionic release of commercially available orthodontic brackets and Copper Ni-Ti archwires. Following the assessment of the elemental composition of the orthodontic wire (Copper Ni-Ti) and the six different brackets (Micro Loc, Equilibrium, OptiMESH(XRT), Gemini, Orthos2, and Rematitan), cyclic polarization curves were obtained for each material to estimate the susceptibility of each alloy to pitting corrosion in 1M lactic acid. Galvanic corrosion between the orthodontic wire and each bracket took place in 1M lactic acid for 28 days at 37 degrees C and then the ionic concentration of Nickel and Chromium was studied. The orthodontic wire is made up from a Ni-Ti alloy with copper additions, while the orthodontic brackets are manufactured by different stainless steel grades or titanium alloys. All tested wires and brackets with the exception of Gemini are not susceptible to pitting corrosion. In galvanic corrosion, following exposure for 28 days, the lowest potential difference (approximately 250 mV) appears for the orthodontic wire Copper Ni-Ti and the bracket made up from pure titanium (Rematitan) or from the stainless steel AISI 316 grade (Micro Loc). Following completion of the galvanic corrosion experiments, measurable quantities of chromium and nickel ions were found in the residual lactic acid solution. PMID:16969817

Darabara, Myrsini S; Bourithis, Lefteris I; Zinelis, Spiros; Papadimitriou, George D

2007-04-01

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Design of an Orthodontic Torque Simulator for Measurement of Bracket Deformation  

Science.gov (United States)

The design and testing of an orthodontic torque simulator that reproduces the effect of archwire rotation on orthodontic brackets is described. This unique device is capable of simultaneously measuring the deformation and loads applied to an orthodontic bracket due to archwire rotation. Archwire rotation is used by orthodontists to correct the inclination of teeth within the mouth. This orthodontic torque simulator will provide knowledge of the deformation and loads applied to orthodontic bracket that will aide clinicians by describing the effect of archwire rotation on brackets. This will also impact that design on new archwirebracket systems by providing an assessment of performance. Deformation of the orthodontic bracket tie wings is measured using a digital image correlation process to measure elastic and plastic deformation. The magnitude of force and moments applied to the bracket though the archwire is also measured using a six-axis load cell. Initial tests have been performed on two orthodontic brackets of varying geometry to demonstrate the measurement capability of the orthodontic torque simulator. The demonstration experiment shows that a Damon Q bracket had a final plastic deformation after a single loading of 0.022 mm while the Speed bracket deformed 0.071 mm. This indicates that the Speed bracket plastically deforms 3.2 times more than the Damon Q bracket for similar magnitude of applied moment. The demonstration experiment demonstrates that bracket geometry affect the deformation of orthodontic brackets and this difference can be detected using the orthodontic torque simulator.

Melenka, G. W.; Nobes, D. S.; Major, P. W.; Carey, J. P.

2013-12-01

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Frictional resistance of ceramic and stainless steel orthodontic brackets.  

Science.gov (United States)

Frictional resistance of orthodontic appliances is recognized by most clinicians to be detrimental to tooth movement. The purpose of this study was to compare planar, static frictional forces among stainless steel and ceramic brackets. Both nitinol and stainless steel rectangular arch wires were passed freely through the slots of a pair of brackets from each type. Tests were carried out in air and in artificial saliva. A 300-gm load was suspended from the arch wire to simulate the normal force, and an incremental horizontal force was applied until movement of the arch wire was initiated. Under all conditions, the stainless steel brackets had lower coefficients of friction than the ceramic brackets. The stainless steel wire generated less friction than nitinol, and friction increased in the presence of artificial saliva in comparison with air alone. These results show that, under experimental conditions, ceramic brackets, nitinol arch wires, and saliva all increase static frictional resistance. PMID:2239837

Pratten, D H; Popli, K; Germane, N; Gunsolley, J C

1990-11-01

18

A comparison of shear bond strength of orthodontic brackets bonded with four different orthodontic adhesives  

Science.gov (United States)

Objectives: The objective of this study is to compare the shear bond strength (SBS) of stainless steel (SS) orthodontic brackets bonded with four different orthodontic adhesives. Materials and Methods: Eighty newly extracted premolars were bonded to 0.022 SS brackets (Ormco, Scafati, Italy) and equally divided into four groups based on adhesive used: (1) Rely-a-Bond (self-cure adhesive, Reliance Orthodontic Product, Inc., Illinois, USA), (2) Transbond XT (light-cure adhesive, 3M Unitek, CA, USA), (3) Transbond Plus (sixth generation self-etch primer, 3M Unitek, CA, USA) with Transbond XT (4) Xeno V (seventh generation self-etch primer, Dentsply, Konstanz, Germany) with Xeno Ortho (light-cure adhesive, Dentsply, Konstanz, Germany) adhesive. Brackets were debonded with a universal testing machine (Model No. 3382 Instron Corp., Canton, Mass, USA). The adhesive remnant index (ARI) was recordedIn addition, the conditioned enamel surfaces were observed under a scanning electron microscope (SEM). Results: Transbond XT (15.49 MPa) attained the highest bond strength. Self-etching adhesives (Xeno V, 13.51 MPa; Transbond Plus, 11.57 MPa) showed clinically acceptable SBS values and almost clean enamel surface after debonding. The analysis of variance (F = 11.85, P < 0.0001) and Chi-square (?2 = 18.16, P < 0.05) tests revealed significant differences among groups. The ARI score of 3 (i.e., All adhesives left on the tooth) to be the most prevalent in Transbond XT (40%), followed by Rely-a-Bond (30%), Transbond Plus with Transbond XT (15%), and Xeno V with Xeno Ortho (10%). Under SEM, enamel surfaces after debonding of the brackets appeared porous when an acid-etching process was performed on the surfaces of Rely-a-Bond and Transbond XT, whereas with self-etching primers enamel presented smooth and almost clean surfaces (Transbond Plus and Xeno V group). Conclusion: All adhesives yielded SBS values higher than the recommended bond strength (5.9-7–8 MPa), Seventh generation self-etching primer Xeno V with Xeno Ortho showed clinically acceptable SBS and the least amount of residual adhesive left on the enamel surface after debonding. PMID:24987660

Sharma, Sudhir; Tandon, Pradeep; Nagar, Amit; Singh, Gyan P; Singh, Alka; Chugh, Vinay K

2014-01-01

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A method for producing controlled fluoride release from an orthodontic bracket.  

Science.gov (United States)

The aim of this study was to manufacture and test, in vitro, a novel modification to provide fluoride-releasing orthodontic brackets. Thirty-two orthodontic brackets were drilled to produce a recess (approximately 1.3 mm in diameter and 0.7 mm in depth) at the centre of the bracket base. Four materials, with and without the addition of sodium fluoride, a glass ionomer cement (Ketac Cem micro), a resin-modified glass ionomer cement (RMGIC; GC Fuji Ortho LC), a zinc phosphate (Zinc Cement Improved), and a resin (Transbond XT) were used to fill the recess in the bracket base. Fluoride release was measured daily during the first week and then weekly for 10 weeks. An ion chromatograph with suppressed conductivity was used for free fluoride ion determination. Statistical analysis to determine the amount of flouride release was undertaken using analysis of variance and Tukey's test. During the first 2 weeks, the resin group, with the addition of 38 per cent sodium fluoride added, released significantly more free fluoride (P < 0.05), but after 2 weeks the fluoride release markedly decreased. After 5 weeks, the RMGIC group, with 15 per cent added sodium fluoride, had significantly higher (P < 0.05) daily fluoride release than the other groups. The findings demonstrated that an appropriate fluoridated material can be used as a fluoride-releasing reservoir in a modified orthodontic bracket to enable it to release fluoride over the period of fixed appliance treatment. PMID:17804428

Li, Song; Hobson, Ross S; Bai, Yuxing; Yan, Zhuoqun; Carrick, Thomas E; McCabe, John F

2007-12-01

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21 CFR 872.5410 - Orthodontic appliance and accessories.  

Science.gov (United States)

...so that pressure can be exerted on the teeth. This device includes the preformed orthodontic band, orthodontic band material, orthodontic elastic band, orthodontic metal bracket, orthodontic wire clamp, preformed orthodontic space...

2010-04-01

 
 
 
 
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Evaluation of Shear Bond Strength of Orthodontic Brackets Bonded with Nano-filled Composites  

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Full Text Available Objectives: The purpose of this study was to evaluate the shear bond strength (SBS of orthodontic brackets bonded with two types of nano-composites in comparison to a conventional orthodontic composite. Materials and Methods: Sixty extracted human first premolars were randomly divided into 3 groups each containing 20 teeth. In group I, a conventional orthodontic composite (Transbond XT was used to bond the brackets, while two nano-composites (Filtek TM Supreme XT and AELITE Aesthetic Enamel were used in groups II and III respectively. The teeth were stored in distilled water at 37°C for 24 hours, thermocycled in distilled water and debonded with a universal testing machine at a crosshead speed of 1 mm/min. The adhesive remnant index (ARI was also evaluated using a stereomicroscope. Results: AELITE Aesthetic Enamel nano-composite revealed a SBS value of 8.44±2.09 MPa, which was higher than Transbond XT (6.91± 2.13 and Filtek TM Supreme XT (6.04± 2.01. Statistical analysis revealed a significant difference between groups II and III (P 0.05. Evaluation of ARI showed that Transbond XT left fewer adhesive remains on teeth after debonding. Conclusion: Results of this study indicate that the aforementioned nano-composites can be successfully used for bonding orthodontic brackets.

Mohammad Sadegh Ahmad Akhoundi

2013-01-01

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

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Full Text Available 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 for 30 s and the weakest after 45 s treatment. Conclusion: The phosphoric acid application time has an effect on the quality and strength of the enamel - bracket bond.

Miti? Vladimir

2008-01-01

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The use of single step adhesives in bonding orthodontic brackets.  

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Full Text Available Previous studies have suggested that the new single-step adhesive systems used in operative dentistry and can bond to both enamel and dentin, require a shorter application time while maintaining adequate bond strength. In orthodontics, several repetitions of the bonding procedure are necessary, therefore, adhesive systems requiring less time for application are of particular interest. The purpose of this study was to determine the effect of incorporating single step adhesives to a traditional bonding system, on the shear bond strength of orthodontic brackets. Sixty recently extracted human teeth were divided into three equal groups. Group I (control: brackets were bonded with the Transbond XT adhesive system (3M/Unitek following the manufacturer's instructions; Group II: Single Bond (3M adhesive was applied to the tooth surface and Transbond XT adhesive paste was used to bond the brackets; Group III: Optibond Solo (Kerr Co. adhesive was applied to the enamel surface and Transbond XT adhesive was used to bond the brackets. Teeth were stored in deionized water at 37oC for 24 hours. A Zwick Universal Testing Machine was used to measure shear bond strength. The shear bond strengths for the three groups tested were; Group ?: 11.8+4.6 Mpa; Group ??: 12.5+3.9 Mpa; and Group ???: 9.7+4.3 Mpa. Analysis of Variance (F=2.37 indicated that there were no significant differences (p>0.05 in the bond strengths among the three groups. In conclusion, the use of single step adhesives to replace the sealant did not significantly affect the shear bond strength of the adhesive system.

L. Von Wald

1999-01-01

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Orthodontic Bracket Manufacturing Tolerances and Dimensional Differences between Select Self-Ligating Brackets  

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Full Text Available In all manufacturing processes there are tolerances; however, orthodontic bracket manufacturers seldom state the slot dimensional tolerances. This experiment develops a novel method of analyzing slot profile dimensions using photographs of the slot. Five points are selected along each wall, and lines are fitted to define a trapezoidal slot shape. This investigation measures slot height at the slot's top and bottom, angles between walls, slot taper, and the linearity of each wall. Slot dimensions for 30 upper right central incisor self-ligating stainless steel brackets from three manufacturers were evaluated. Speed brackets have a slot height 2% smaller than the nominal 0.559?mm size and have a slightly convergent taper. In-Ovation brackets have a divergent taper at an average angle of 1.47 degrees. In-Ovation is closest to the nominal value of slot height at the slot base and has the smallest manufacturing tolerances. Damon Q brackets are the most rectangular in shape, with nearly 90-degree corners between the slot bottom and walls. Damon slot height is on average 3% oversized.

Thomas W. Major

2010-01-01

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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)

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Coating and Surface Treatments on Orthodontic Metallic Materials  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Metallic biomaterials have been extensively used in orthodontics throughout history. Gold, stainless steel, cobalt-chromium alloys, titanium and its alloys, among other metallic biomaterials, have been part of the orthodontic armamentarium since the twentieth century. Metals and alloys possess outstanding properties and offer numerous possibilities for the fabrication of orthodontic devices such as brackets, wires, bands, ligatures, among others. However, these materials have drawbacks that c...

Claudia García; Santiago Arango; Alejandro Peláez-Vargas

2012-01-01

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Rebonding of unused brackets with different orthodontic adhesives  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english 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

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

2012-04-01

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Rebonding of unused brackets with different orthodontic adhesives  

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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.

Emigdio Enrique Orellana Jimenez

2012-04-01

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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)

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Effect of different methods of enamel conditioning on bond strength of orthodontic brackets  

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Full Text Available Background and Aim: With the introduction of different bondable restorative materials in dentistry, various methods have been suggested to enhance the polymerization and shear bond strength of these materials. The aim of this study was to determine the effects of different methods of enamel conditioning on bond strength of orthodontic brackets and on the bracket/ adhesive failure mode. Materials and Methods: In this experimental in vitro study, brackets were bonded to thirty-six bovine incisor teeth with different protocols according to the manufacturer's instructions as follows: Group 1: conventional multistep adhesive (n=12; Group 2: self-etching primer system (n=12; Group 3: acid+self-etching primer system (n=12. Specimens were loaded in a universal testing machine (Instron, Canton and Mass and the mode of failure was recorded. Data were analyzed by ANOVA and Kruskall-Wallis tests with p<0.05 as the limit of significance. Results: The mean shear bond strength was 11.7 ± 4.2, 10.5 ± 4.4, and 10.9 ± 4.8 MPa for group 1, 2, and 3 respectively. There was no significant difference in bond strength among the three groups (P=0.800. No significant difference was observed among the three groups with respect to residual adhesive on the enamel surfaces (P=0.554. Conclusion: Based on the results of the present study, the use of self-etching primers may be an alternative to conventional phosphoric acid pre-treatment in orthodontic bonding.

Davari AR

2007-01-01

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Effect of fluoride on tooth erosion around orthodontic brackets  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese O objetivo do presente estudo foi avaliar o efeito do flúor na prevenção da erosão do esmalte circunjacente a braquetes ortodônticos sob desafio erosivo. Braquetes edgewise foram colados com resina TransbondTM XT na superfície vestibular de 40 incisivos bovinos. Os dentes foram divididos em 4 grupos [...] (n = 10): G1: Saliva remineralizadora; G2: Desafio erosivo; G3: Grupo experimental submetido à aplicação tópica de flúor gel neutro (NaF a 2%) antes do desafio erosivo; G4: Grupo experimental submetido à três aplicações diárias de dentifrício fluoretado (1500 ppmF PFM) durante o desafio erosivo. Após 14 dias de desafio erosivo, foi realizado exame visual e táctil por dois examinadores calibrados e treinados (Kappa = 0,867). Os escores utilizados foram: 0 = Esmalte hígido, 1 = Esmalte desmineralizado sem cavidade, 2 = Esmalte desmineralizado com cavidade, 3 = Esmalte remineralizado sem cavidade, 4 = Esmalte remineralizado com cavidade. Foram utilizados os testes de Kruskal-Wallis e Mann-Whitney para determinar os níveis de erosão, estabelecendo um intervalo de confiança de 95% (p Abstract in english The aim of the present study was to evaluate the effect of fluoride in prevention of tooth erosion around orthodontic brackets under erosive challenge. Edgewise brackets were bonded with TransbondTM XT composite on vestibular surface of 40 bovine incisors. The teeth were assigned to 4 groups (n=10): [...] G1: Remineralizing saliva; G2: Erosive challenge; G3: Experimental group submitted to topical application of neutral fluoride gel (2% NaF) before erosive challenge; G4: Experimental group submitted to three daily applications of fluoride dentifrice (PFM 1500 ppmF) during erosive challenge. After 14 days of erosive challenge, direct visual and tactile examination were performed by two calibrated and trained examiners (Kappa = 0.867). The following scores were used: 0 = Intact enamel, 1 = Demineralized enamel without cavity, 2 = Demineralized enamel with cavity, 3 = Remineralized enamel without cavity, 4 = Remineralized enamel with cavity. Kruskal-Wallis and Mann-Whitney tests were applied to determine erosion levels, establishing a confidence interval of 95% (p

Erika Machado, Caldeira; Tatiana Kelly da Silva, Fidalgo; Paula, Passalini; Mariana, Marquezan; Lucianne Cople, Maia; Matilde da Cunha Gonçalves, Nojima.

2012-10-01

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Trial production of titanium orthodontic brackets fabricated by metal injection molding (MIM) with sintering.  

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Safety and esthetics are two indispensable factors to consider when fabricating orthodontic brackets. However, these factors are not easily achieved when conventional techniques (including forging and casting) are used in the mass production of titanium brackets, albeit the brackets exhibit excellent biocompatibility. In the present study, orthodontic brackets were manufactured by metal powder injection molding with sintering. Brackets with three different base designs were made and subjected to compression shear tests for evaluation of their bonding strength to enamel substrate. The shapes given to the dimple of the base were spherical, oval, and grooved. The maximum shear forces for each type were 11.1 kgf, 7.6 kgf, and 18.5 kgf, respectively. The bonding strengths of the titanium bracket were equivalent to those obtained with conventional stainless steel brackets. Moreover, uniform distribution of Vickers hardness values (average, 240 +/- 40 Hv) measured at three locations indicated that the titanium bracket was uniformly sintered. Accordingly, titanium brackets thus fabricated exhibit a potential for clinical application. PMID:8876601

Deguchi, T; Ito, M; Obata, A; Koh, Y; Yamagishi, T; Oshida, Y

1996-07-01

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Transparent magnesium aluminate spinel: a prospective biomaterial for esthetic orthodontic brackets.  

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Adult orthodontics is recently gaining popularity due to its importance in esthetics, oral and general health. However, none of the currently available alumina or zirconia based ceramic orthodontic brackets meet the esthetic demands of adult patients. Inherent hexagonal lattice structure and associated birefringence limits the visible light transmission in polycrystalline alumina and make them appear white and non transparent. Hence focus of the present study was to assess the feasibility of using magnesium aluminate (MgAl2O4) spinel; a member of the transparent ceramic family for esthetic orthodontic brackets. Transparent spinel specimens were developed from commercially available white spinel powder through colloidal shaping followed by pressureless sintering and hot isostatic pressing at optimum conditions of temperature and pressure. Samples were characterized for chemical composition, phases, density, hardness, flexural strength, fracture toughness and optical transmission. Biocompatibility was evaluated with in-vitro cell line experiments for cytotoxicity, apoptosis and genotoxicity. Results showed that transparent spinel samples had requisite physico-chemical, mechanical, optical and excellent biocompatibility for fabricating orthodontic brackets. Transparent spinel developed through this method demonstrated its possibility as a prospective biomaterial for developing esthetic orthodontic brackets. PMID:25027301

Krishnan, Manu; Tiwari, Brijesh; Seema, Saraswathy; Kalra, Namitha; Biswas, Papiya; Rajeswari, Kotikalapudi; Suresh, Madireddy Buchi; Johnson, Roy; Gokhale, Nitin M; Iyer, Satish R; Londhe, Sanjay; Arora, Vimal; Tripathi, Rajendra P

2014-11-01

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

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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

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

2014-01-01

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Shear bond strength of precoated orthodontic brackets: an in vivo study  

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Full Text Available Ali H HassanDepartment of Preventive Dental Sciences, Faculty of Dentistry, King Abdulaziz University, Jeddah, Saudi ArabiaObjective: To evaluate the shear bond strength of precoated orthodontic brackets bonded with self-etching primer relative to that of noncoated conventionally-bonded brackets at two different time intervals.Methods: Twenty-one subjects were selected for randomized split-mouth bonding of two types of brackets to the maxillary arch. Half of the teeth had precoated brackets bonded using selfetching adhesive, and the other half had regular brackets bonded using Transbond XT adhesive. Nitinol wires were tied to the upper arch and were left until the time of debonding. The patients were randomly divided into two groups: one debonded after one hour and the other debonded two weeks after the initial wire placement. The shear bond strength was directly recorded from the patients’ mouths using an in vivo debonding device.Results: There were no significant differences in shear bond strength between the precoated and conventional groups or within each group at different time intervals. There were significant differences between anterior and posterior teeth in both the precoated and conventional groups. Conclusion: Pre-coated brackets bonded with self-etching adhesive have the same bonding strength as the conventionally bonded brackets.Keywords: shear bond, bonding, orthodontics, precoated, brackets, self-etching adhesive

Ali H Hassan

2010-06-01

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Orthodontic brackets in high field MR imaging: experimental evaluation of magnetic field interactions at 3.0 tesla  

International Nuclear Information System (INIS)

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 FZ [mN] was evaluated by determining the deflection angle ?[ ] using the established deflection angle test according to the ASTM guidelines. The magnetic-field-induced rotational force Frot 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 ? was found to be > 45 and the translational force exceeded the gravitational force FG on the particular bracket (FZ: 1.2-45.7 mN). The translational force FZ was found to be up to 68.5 times greater than the gravitational force FG (FZ/FG: 1.4-68.5). The rotational force Frot 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.)

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Clinical evaluation of the failure rate of metallic brackets bonded with orthodontic composites  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese O objetivo do presente estudo foi avaliar in vivo a taxa de falha de braquetes metálicos colados com dois compósitos ortodônticos. Dezenove pacientes com idades entre 10,5 e 38,7 anos, que necessitavam de tratamento ortodôntico corretivo, foram selecionados para estudo. As superfícies de esmalte de [...] segundos pré-molares a segundos pré-molares foram tratadas com Transbond Plus Self-Etching Primer (3M Unitek). Em seguida, 380 bráquetes foram colados nos dentes superiores e inferiores, como segue: 190 com compósito Transbond XT (3M Unitek) (controle) e 190 com Transbond Plus Color Change (3M Unitek) (experimental), em quadrantes contralaterais. Os bráquetes colados foram fotopolimerizados por 40 s e arcos de alinhamento inicial foram inseridos. As taxas de insucesso na adesão foram registrados durante um período de seis meses. No final da avaliação, seis falhas de adesão ocorreram, três para cada composto. Para a análise estatística foram utilizados os testes de Kaplan-Meyer e log-rank (Mantel-Cox), e não houve diferença estatisticamente significante entre os materiais (p=0,999). Ambos compósitos, Transbond XT e Transbond Plus Color Change, tiveram baixas taxas de descolagem durante o período de estudo Abstract in english The purpose of the present study was to evaluate in vivo the failure rate of metallic brackets bonded with two orthodontic composites. Nineteen patients with ages ranging from 10.5 to 38.7 years needing corrective orthodontic treatment were selected for study. The enamel surfaces from second premola [...] rs to second premolars were treated with Transbond Plus-Self Etching Primer (3M Unitek). Next, 380 orthodontic brackets were bonded on maxillary and mandibular teeth, as follows: 190 with Transbond XT composite (3M Unitek) (control) and 190 with Transbond Plus Color Change (3M Unitek) (experimental) in contralateral quadrants. The bonded brackets were light cured for 40 s, and initial alignment archwires were inserted. Bond failure rates were recorded over a six-month period. At the end of the evaluation, six bond failures occurred, three for each composite. Kaplan-Meyer method and log-rank test (Mantel-Cox) was used for statistical analysis, and no statistically significant difference was found between the materials (p=0.999). Both Transbond XT and Transbond Plus Color Change composites had low debonding rates over the study period.

Fábio Lourenço, Romano; Rodrigo Alexandre, Valério; Jaciara Miranda, Gomes-Silva; José Tarcísio Lima, Ferreira; Gisele, Faria; Maria Cristina, Borsatto.

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

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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.

Gabriel Schmidt Dolci

2008-06-01

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

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese 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.

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

2008-06-01

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Frictional and mechanical properties of diamond-like carbon-coated orthodontic brackets.  

Science.gov (United States)

This study investigated the effects of a diamond-like carbon (DLC) coating on frictional and mechanical properties of orthodontic brackets. DLC films were deposited on stainless steel brackets using the plasma-based ion implantation/deposition (PBIID) method under two different atmospheric conditions. As-received metal brackets served as the control. Two sizes of stainless steel archwires, 0.018 inch diameter and 0.017 × 0.025 inch cross-section dimensions, were used for measuring static and kinetic friction by drawing the archwires through the bracket slots, using a mechanical testing machine (n = 10). The DLC-coated brackets were observed with a scanning electron microscope (SEM). Values of hardness and elastic modulus were obtained by nanoindentation testing (n = 10). Friction forces were compared by one-way analysis of variance and the Scheffé test. The hardness and elastic modulus of the brackets were compared using Kruskal-Wallis and Mann-Whitney U-tests. SEM photomicrographs showed DLC layers on the bracket surfaces with thickness of approximately 5-7 ?m. DLC-coated brackets deposited under condition 2 showed significantly less static frictional force for the stainless steel wire with 0.017 × 0.025 inch cross-section dimensions than as-received brackets and DLC-coated brackets deposited under condition 1, although both DLC-coated brackets showed significantly less kinetic frictional force than as-received brackets. The hardness of the DLC layers was much higher than that of the as-received bracket surfaces. In conclusion, the surfaces of metal brackets can be successfully modified by the PBIID method to create a DLC layer, and the DLC-coating process significantly reduces frictional forces. PMID:21934113

Muguruma, Takeshi; Iijima, Masahiro; Brantley, William A; Nakagaki, Susumu; Endo, Kazuhiko; Mizoguchi, Itaru

2013-04-01

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

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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. Orthodontic 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 < 0.05. The average bond strengths (range: 90.18-90.89 kgf/cm² did not differ among the three groups. The Colgate 360º showed less bristle wear and a better bristle tip morphology than the Oral B Indicator 35 toothbrush. However, use of either toothbrush did not decrease the bond strength of the orthodontic brackets. Therefore, patients undergoing orthodontic therapy can safely use either toothbrush.

Guilherme José Pimentel Lopes de Oliveira

2010-09-01

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Effect of elastomeric ligatures on frictional forces between the archwire and orthodontic bracket  

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Full Text Available SciELO Brazil | Language: English Abstract in english AIM: To evaluate the frictional force between the archwire and orthodontic bracket generated by elastomeric ligatures with polymer coating (Super slick, TP Orthodontics) and conventional ligatures (Morelli) using two types of insertion techniques. METHODS: Forty elastomeric ligatures, 20 with polyme [...] r coating and 20 conventional, were evaluated. Each type of ligature was separated into two groups (n=10), according to the insertion mode: conventional or crossed (from mesial to distal region crossed in front). To analyze friction, 40 5-cm-long segments of stainless steel orthodontic archwire 0.019" x 0.025" (Morelli) and Edgewise brackets (slot 0.022" x 0.028"; Morelli) were used. Each set (bracket, wire and elastic) was submitted to frictional testing in a universal test machine (Instron 4411) at a crosshead speed of 5 mm/min. Each bracket was moved 5 mm on the wire, with maximum friction and mean friction being recorded by software. Three readouts were taken for each bracket. Data were submitted to two-way ANOVA and Tukey's test (p

Flávia Ramos, Venâncio; Sílvia Amélia Scudeler, Vedovello; Carlos Alberto Malanconi, Tubel; Viviane Veroni, Degan; Adriana Simone, Lucato; Letícia Nery, Lealdim.

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Effect of elastomeric ligatures on frictional forces between the archwire and orthodontic bracket  

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Full Text Available SciELO Brazil | Language: English Abstract in english AIM: To evaluate the frictional force between the archwire and orthodontic bracket generated by elastomeric ligatures with polymer coating (Super slick, TP Orthodontics) and conventional ligatures (Morelli) using two types of insertion techniques. METHODS: Forty elastomeric ligatures, 20 with polyme [...] r coating and 20 conventional, were evaluated. Each type of ligature was separated into two groups (n=10), according to the insertion mode: conventional or crossed (from mesial to distal region crossed in front). To analyze friction, 40 5-cm-long segments of stainless steel orthodontic archwire 0.019" x 0.025" (Morelli) and Edgewise brackets (slot 0.022" x 0.028"; Morelli) were used. Each set (bracket, wire and elastic) was submitted to frictional testing in a universal test machine (Instron 4411) at a crosshead speed of 5 mm/min. Each bracket was moved 5 mm on the wire, with maximum friction and mean friction being recorded by software. Three readouts were taken for each bracket. Data were submitted to two-way ANOVA and Tukey's test (p

Flávia Ramos, Venâncio; Sílvia Amélia Scudeler, Vedovello; Carlos Alberto Malanconi, Tubel; Viviane Veroni, Degan; Adriana Simone, Lucato; Letícia Nery, Lealdim.

2013-03-01

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Influence of surface treatments on the shear bond strength of orthodontic brackets to porcelain  

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The purpose of this study was to investigate the effect of various surface treatments after different storage time and thermocycling on the shear bond strength of orthodontic brackets to the feldspathic porcelain surfaces. 128 disc-shaped porcelain specimens were randomly assigned to the following surface treatments: 9.6% HFA, 9.6% HFA combined with silane, 50 ? aluminum trioxide sandblasting followed by silane and application of silane after 37% phosphoric acid. Metal or ceramic brackets were bonded onto each treated porcelain facet with light cured resin. The samples were stored in 37 °C water 1 day or 7 days, thermocycled 500 times from 5 to 55 °C. The shear bond strengths were measured (1 mm/min), and statistically analyzed. The bond failure sites were classified according to ARI system. The surface of the glazed, sandblasted, hydrofluoric and phosphoric acid etched porcelain were examined with SEM. All groups achieved reasonable bond strengths to withstand the application of orthodontic forces. Water storage for 7 days caused lower shear bond strength than that of 1 day. But there is no statistically significant difference between the two groups. The mean shear bond strength provided by ceramic bracket with mechanical retention had no statistical difference with that of metal bracket. Therefore, the optimal treatment for orthodontic brackets bonding to feldspathic porcelain was to apply phosphoric acid combined with silane.

Wang, Cong; Zeng, Jishan; Wang, Shaoan; Yang, Zheng; Huang, Qian; Chen, Pixiu; Zhou, Shujuan; Liu, Xiaoqing

2008-11-01

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In vitro evaluation of corrosion and cytotoxicity of orthodontic brackets.  

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The corrosion resistance of AISI 304 stainless steel (AISI 304 SS) and manganese stainless steel (low-nickel SS) brackets in artificial saliva was investigated. The cytotoxic effects of their corrosion products on L929 cell culture were compared by two assays, crystal violet, to evaluate cell viability, and MTT (3-[4,5-dimethylthiazol-2-yl]2,5-diphenyltetrazolium bromide), for cell metabolism and proliferation. The atomic absorption spectroscopic analysis of the corrosion products demonstrated that nickel and manganese ion concentrations were higher for the AISI 304 SS-bracket immersion solution as compared with the low-nickel SS brackets. Scanning electron microscopy and energy-dispersive spectroscopy demonstrated less corrosion resistance for the AISI 304 SS brackets. Although none of the bracket extracts altered L929 cell viability or morphology, the AISI 304 SS-bracket extracts decreased cellular metabolism slightly. The results indicated that the low-nickel SS presents better in vitro biocompatibility than AISI 304 SS brackets. Abbreviations used: AISI, American Iron and Steel Institute; EDS, energy-dispersive spectroscopy; OD, optical density; ISO, International Organization for Standardization; MTT, (3-{4,5 dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide; NiSO(4), nickel sulfate; SEM, standard error of the mean; WHO, World Health Organization; and TNF, tumor necrosis factor. PMID:17452565

Costa, M T; Lenza, M A; Gosch, C S; Costa, I; Ribeiro-Dias, F

2007-05-01

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Orthodontic molar brackets: the effect of three different base designs on shear bond strength.  

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The purpose of the study was to assess the relative base designs of three different maxillary molar stainless steel brackets with reference to the shear bond strength of three different adhesive resins. The molar brackets used were Victory series (3M Unitek), Upper Molar (GAC) and Optimesh XRT (Ormco). The adhesives used were Transbond XT (3M Unitek), Enlight (Ormco) and Sure Ortho Light Bond (Sure Orthodontics). The human enamel specimens (144) were randomly divided into nine groups and each group (n=16) was allocated to a bracket/adhesive combination. The contact surface of each of the bracket bases was measured three dimensionally using a reflex microscope. The base designs were also subjected to further microscopic investigations. The brackets were bonded to the enamel, temperature cycled and the shear bond strength was measured. The size and design of each of the brackets was different. The base size, surface treatment, mesh strand diameter and aperture size of the bracket base mesh have a significant effect on the shear bond strength at the bracket/adhesive interface. The shear bond strengths of all three Ormco bracket/adhesive resin combinations (5.8-6.8 MPa) were significantly lower (p<0.05; Kruskal-Wallis) than the other six bracket/adhesive combinations (9.4-12.1 MPa). The different adhesive types (3 types) could not be mainly responsible for the low shear bond values found for the Ormco bracket. The 3M Unitek combination of the Victory series bracket and Transbond XT adhesive proved to have a high shear bond strength without enamel damage. PMID:23675217

Hudson, Athol P; Grobler, Sias R; Harris, Angela M P

2011-03-01

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Hypersensitivity reactions to orthodontic materials.  

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Full Text Available Most allergic reactions that may be observed during orthodontic treatment are manifestations of hypersensitivity to potentially allergenic factors of orthodontic materials. These factors basically include the latex material of disposable elastic surgical gloves and of most elastic orthodontic materials and the nickel contained in the alloys of metal orthodontic appliances. Allergic hypersensitivity reactions may involve extra- and intra-oral clinical signs usually including localized manifestations, at the site of contact with the allergen, such as erythema, edema, itching of the skin or oral mucosa and more rarely systemic manifestations, such as generalized rash and dyspnea, whereas in extreme situations aphylactic reaction may be observed. In any case, when taking the patient’s medical history, it is necessary to record in detail all previous allergic episodes of any type. Where considered necessary, the diagnosis of hypersensitivity to specific materials is documented by the allergiologist following specialized dermatological or hematological tests. Although the phenomenon of hypersensitivity to orthodontic materials is not common in routine clinical practice, in cases where an allergic reaction is observed, the prompt diagnosis is of utmost importance, and it should be followed by the immediate interruption of exposure to the allergen along with the substitution of any suspected /potent allergens or/and modification of treatment planning. The aim of this review is to describe, on the basis of modern literature, the latest evidence-based scientific data concerning etiology, diagnosis and treatment of allergic reactions to materials most frequently used during orthodontic treatment.

Philippos N. Synodinos

2005-01-01

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The tensile bond strength of new and rebonded stainless steel orthodontic brackets.  

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The study investigated the effect on the tensile/peel bond strength of the variables associated with the bracket base, the enamel surface, and the type of adhesive when both new and used brackets were rebonded to a previously bonded enamel surface. The tensile/peel bond strength was firstly evaluated for three different types of stainless steel orthodontic bracket/base combinations. The cast integral base gave a significantly lower bond strength than the foil-mesh and photo-etched bases. Following debonding, a group of new brackets were bonded to the teeth using a chemically-activated or a light-cured adhesive. The old adhesive had been removed from the enamel by either a hand scaler or a tungsten-carbide bur. The rebonded new brackets demonstrated a small, but statistically significant fall in bond strength. No differences were found between the enamel preparations or the adhesives. A further group of previously debonded brackets were rebonded to the same teeth. The bracket bases were prepared by either smoothing with a green stone or heating in a bunsen flame followed by sandblasting and electropolishing. Highly significant falls in bond strength were obtained with all the bases. No significant differences were found between the two methods of bracket preparation. PMID:8500538

Regan, D; LeMasney, B; van Noort, R

1993-04-01

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

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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.

Farzaneh Ahrari

2013-01-01

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Evaluation of acquired acid resistance of enamel surrounding orthodontic brackets irradiated by laser and fluoride application.  

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Demineralization of enamel around orthodontic brackets is a clinical problem which can lead to some esthetic concerns like white spot lesions. The aim of this in vitro study was to evaluate the effect of the Er, Cr:YSGG laser and fluoride application on the acid resistance of enamel adjacent to orthodontic brackets. A total of 60 healthy, permanent, human premolars were selected and bonded with brackets, then they were randomly assigned to four groups (n?=?15): topical APF gel (1.23 % F, pH 3.5, for 4 min); Er,Cr:YSGG laser (P:0.25 W, E:12.5 mJ, RR:20 Hz, PD:140 ?s, 11 % air, without water, for 10 s); fluoride + laser group (F + L), and control group (C). All specimens were demineralized for 10 days in a 0.2 M acetate buffer solution, and the calcium content were subsequently determined with atomic absorption spectrometry. There were significant differences between the calcium content of F + L and F group in comparison to control group. The least concentration of calcium was seen in F + L group, and the most value was observed in C group. Combination of Er, Cr:YSGG laser with fluoride and fluoride alone decreased enamel solubility significantly more than laser alone. In addition, combination of laser and fluoride leads to less consumption of fluoride amount. And patients can use it at the beginning of treatment instead of daily use of fluoride. So we suggest using it in preventing enamel demineralization around orthodontic brackets. PMID:23624699

Fekrazad, Reza; Ebrahimpour, Leila

2014-11-01

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

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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 and 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<0.05. Group 3 had statistically significant lower bond strength than Groups 2, 4, and 6, but no statistically significant differences were found on comparison to Groups 1 and 5. A larger number of fractures at the bracket/composite interface were evidenced by the ARI scores. OrthoPrimer bonding agent yielded higher bond strength in the groups using either conventional or sandblasted polycarbonate brackets, which was not observed in the groups using metallic brackets.

Matheus Melo Pithon

2007-04-01

52

Comparative Evaluation of Shear Bond Strength of Orthodontic Brackets on Pretreatment with CPPACP, Fluor Protector and Phosflur: An In-vitro Study  

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Objective: The purpose of this study is to evaluate bond strength, bracket tooth interface of Orthodontic brackets that are bonded for fixed Orthodontic treatment procedure on pretreatment with CPPACP, Fluor Protector and Phosflur. The goal is to assess the adhesive remnants following application of these remineralizing agents using Adhesive Remnant Index. Materials and Methods: Two hundred freshly extracted premolar teeth each divided into Control, CPP-ACP, Fluor Protector and Phosflur. Teeth were pretreated with these agents prior to bonding procedure. Shear Bond Strength was tested using a Universal Testing Machine. A jig was attached to upper jaw of the machine. The acrylic block containing the embedded teeth was secured in the lower jaw of the machine such that the bracket base of the teeth parallel the direction of the shear force at a crosshead speed of 1 mm/minute until bracket failure. The force required to dislodge the bracket was recorded. Results: Mean Shear bond strength value is highest for Phosflur (15.3658 ± 2.4546 ) followed by Fluor Protector , CPP-ACP and lowest for Control (7.0462 ± 0.8838 MPa). Conclusion: Phosflur, Fluor protector,CPP-ACP have comparable Shear bond strength values in comparison to control. PMID:24995233

2014-01-01

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Shear bond strength of orthodontic brackets after acid-etched and erbium-doped yttrium aluminum garnet laser-etched  

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Background: Laser ablation has been suggested as an alternative method to acid etching; however, previous studies have obtained contrasting results. The purpose of this study was to compare the shear bond strength (SBS) and fracture mode of orthodontic brackets that are bonded to enamel etched with acid and erbium-doped yttrium aluminum garnet (Er:YAG) laser. Materials and Methods: In this experimental in vitro study, buccal surfaces of 15 non-carious human premolars were divided into mesial and distal regions. Randomly, one of the regions was etched with 37% phosphoric acid for 15 s and another region irradiated with Er:YAG laser at 100 mJ energy and 20 Hz frequency for 20 s. Stainless steel brackets were then bonded using Transbond XT, following which all the samples were stored in distilled water for 24 h and then subjected to 500 thermal cycles. SBS was tested by a chisel edge, mounted on the crosshead of universal testing machine. After debonding, the teeth were examined under ×10 magnification and adhesive remnant index (ARI) score determined. SBS and ARI scores of the two groups were then compared using t-test and Mann-Whitney U test. Significant level was set at P < 0.05. Results: The mean SBS of the laser group (16.61 ± 7.7 MPa) was not significantly different from that of the acid-etched group (18.86 ± 6.09 MPa) (P = 0.41). There was no significant difference in the ARI scores between two groups (P = 0.08). However, in the laser group, more adhesive remained on the brackets, which is not suitable for orthodontic purposes. Conclusion: Laser etching at 100 mJ energy produced bond strength similar to acid etching. Therefore, Er:YAG laser may be an alternative method for conventional acid-etching. PMID:25097641

Alavi, Shiva; Birang, Reza; Hajizadeh, Fatemeh

2014-01-01

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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  

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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.)

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

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

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english 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

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

56

Optimal enamel conditioning strategy for rebonding orthodontic brackets: a laboratory study  

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Objective: To compare the conventional etching and primer method (CEP) and the self-etching primer method (SEP) in rebonding brackets. Methods: Forty human maxillary second premolars extracted for orthodontic purpose were randomly divided into 4 equal groups. Group 1 and Group 2 were bonded using the CEP method; Group 3 and Group 4 using the SEP method. All the brackets were debonded and 40 new brackets were rebonded with four different protocols after surface cleaning: Group 1: CEP + adhesive; Group 2: CEP without etch step + adhesive; Group 3: SEP + adhesive; Group 4: non-acidic primer + adhesive. Then, the shear bond strength (SBS) of each group was tested and the measurements of adhesive remnant index scores (ARI) and SEM examination were performed. Results: The mean SBSs for Group 1, 2, 3 and 4 were 14.18, 6.57, 11.90, 5.91 MPa, respectively. Statistical differences of the SBS existed between Group 1 and 2 (P SBS and ARI of the rebonded brackets were showed between CEP and SEP methods. PMID:25356128

Zhang, Qi-Feng; Yao, Hua; Li, Zhi-Yong; Jin, Li; Wang, Hui-Ming

2014-01-01

57

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

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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...

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

2011-01-01

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

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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 ...

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

2007-01-01

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

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese 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

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

2014-06-01

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

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese 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

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

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

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Full Text Available SciELO Brazil | Language: English Abstract in english 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

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

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

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Full Text Available SciELO Brazil | Language: English Abstract in english 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

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

2010-09-01

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

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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.

Berahman Sabzevari

2013-12-01

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Comparison of friction produced by two types of orthodontic bracket protectors  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese 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.

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

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Comparison of friction produced by two types of orthodontic bracket protectors  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese 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.

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

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

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese 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

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

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

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese 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

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

2013-08-01

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Effect of applying a sustained force during bonding orthodontic brackets on the adhesive layer and on shear bond strength.  

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The objective of this research was to investigate the effect of applying a sustained seating force during bonding on the adhesive layer and on shear bond strength (SBS) of orthodontic brackets. Forty human premolars divided into two groups were included in the study. Stainless steel brackets were bonded to the premolars with Transbond XT light cure adhesive and Transbond Plus Self Etch Primer (SEP). The brackets in both groups were subjected to an initial seating force of 300 g for 3 seconds, sufficient to position the bracket. The seating force was maintained throughout the 40 seconds of light curing in group 2. SBS was tested 24 hours after bracket bonding with a shear blade using an Instron testing unit at a crosshead speed of 2 mm/minute. A Student's t-test was used to compare the bond strength of the two groups and a chi-square test to compare the frequencies of the adhesive remnant index (ARI) scores. The mean SBS was significantly different between the two groups (P=0.025). The bond strength was higher (mean 8.15±0.89 MPa) in group 2 compared with group 1 (mean 7.39±1.14 MPa). There was no significant difference (P=0.440) in the ARI scores between the two groups. Applying a sustained seating force during orthodontic bracket bonding improves bond strength but does not change the distribution of the ARI scores. PMID:21030470

Montasser, Mona A

2011-08-01

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Brackets, epitopes and flash memory cards: a futuristic view of clinical orthodontics.  

Science.gov (United States)

Orthodontics continues to be a profession anchored in traditional technology using appliances that cause inflammatory periodontal ligament (PDL) responses. Existing concepts of biological tooth movement based largely on histological tissue observations and the application of physical principles require major reassessment. In the next millennium, the genome revolution and knowledge of protein production and control could lead to the genetic correction of dentofacial anomalies and pain-free, biomolecular methods of malocclusion correction and long-term stability. A fundamental change is likely to be the abolition of bracket systems and their replacement with preprogrammed microchips driven by computers, and the control of PDL blood vessels and cells by pharmacological targeting. Future survival of the profession will depend on a radically different specialist who will be educated with a postgraduate curriculum based on molecular biology and computer engineering. PMID:10806932

Sims, M R

1999-11-01

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A Comparison of the Shear Bond Strength of Orthodontic Brackets Bonded With Light-Emitting Diode and Halogen Light-Curing Units  

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Full Text Available Statement of the problem: Various methods such as light emitting diode (LED have been used to enhance the polymerization of resin-based orthodontic adhesives. There is a lack of information on the advantages and disadvantages of different light curing systems.Purpose: The aim of this study was to compare the effect of LED and halogen light curing systems on the shear bond strength of orthodontic brackets.Materials and Methods: Forty extracted human premolars were etched with 37% phosphoric acid and cleansed with water spray and air dried. The sealant was applied on the tooth surface and the brackets were bonded using Transbond adhesive (3M Unitek,Monrovia, Calif. Adhesives were cured for 40 and 20 seconds with halogen (Blue Light, APOZA, Taiwan and LED (Blue dent, Smart, Yugoslavia light-curing systems,respectively. Specimens were thermocycled 2500 times (from 5 to 55 °C and the shear bond strength of the adhesive system was evaluated with an Universal testing machine (Zwick GmbH, Ulm, Germany at a crosshead speed of 1 mm/min until the bracketswere detached from the tooth. Adhesive remnant index (ARI scores were determined after bracket failure. The data were submitted to statistical analysis, using Mann-Whitney analysis and t-test.Results: No significant difference was found in bond strength between the LED and halogen groups (P=0.12. A significant difference was not observed in the adhesive remnant index scores between the two groups (P=0.97.Conclusion: Within the limitations of this in vitro study, the shear bond strength of resin-based orthodontic adhesives cured with a LED was statistically equivalent to those cured with a conventional halogen-based unit. LED light-curing units can be suggested for the polymerization of orthodontic bonding adhesives.

SM. Abtahi

2006-09-01

71

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

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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.

M. Hashem-Hoseini

2008-12-01

72

Bonding Orthodontic Ceramic Brackets to Ceramic Restorations: Evaluation of Different Surface Conditioning Methods  

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Full Text Available The purpose of this study was to compare the shear bond strength and Adhesive Remnant Index of four different veneering ceramic materials to ceramic brackets. Additionallly, a further aim of this study was to overcome the etching using hydrofluoric acid which is noxious and could seriously damage the corneas of the eyes. Two surface conditioning methods of four ceramic materials before bonding brackets were examined: in group 1 an air particle abrasion with 25 ?m aluminium trioxide (4 seconds at a pressure of 2.5 bars and subsequently a silane coupling agent (Espe Sil, 3M Unitek, Monrovia, USA was applicated on one side of each ceramic specimen (10 per group. In group 2 one side of each sample (20 per group was etched with 37.0 per cent orthophosphoric acid for two minutes and was followed by a silane application (Espe Sil, 3M Unitek, Monrovia, USA. After this procedure the self-ligating ceramic brackets Clarity SL (3M Unitek, Monrovia, USA brackets were bonded to the ceramic blocks and a thermocycling process started (5°C - 55°C, 6000 cycles. Then, shear bond strength and Adhesive Remnant Index (ARI were measured. To determine statistical differences Oneway-ANOVA and Tukey Post-hoc test were performed. Hydrofluoric acid seems not to be justifiable anymore for preparing the surface of dental ceramic restorations before bracket bonding. Sandblasting with 25 ?m aluminium trioxide and the use of orthophosphoric acid (37.0 per cent seem to prepare the surface of ceramic restoration sufficiently before ceramic bracket bonding. The found level of shear bond strength values seems to be sufficient for bonding ceramic brackets to ceramic restorations.

Andreas Faltermeier

2013-07-01

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The effect of using a new experimental self-etch primer/adhesive on the shear bond strength of orthodontic brackets: a comparative study.  

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Full Text Available Conventional adhesive systems use three different agents, an enamel conditioner, a primer solution, and an adhesive resin during the bonding of orthodontic brackets to enamel. A unique characteristic of some new bonding systems in operative dentistry, is that they combine the conditioning and priming agents into a single application. Combining conditioning and priming saves time and should be more cost-effective to the clinician and indirectly to the patient. AIM: To assess and compare the effects of using two self-etch primers including an experimental one, on the shear bond strength of orthodontic brackets. DESIGN: In vitro study. SETTING: College of Dentistry, University of Iowa. MATERIAL AND METHOD: The brackets were bonded to extracted human teeth according to one of three protocols; Group I (Control: Teeth were etched with 37% phosphoric acid. After applying the sealant, the brackets were bonded with Transbond XT (3M Unitek, Monrovia, California, USA and light cured for 20 seconds. Group II: A self-etch acidic primer (ESPE Dental AG, Seefeld, Germany was placed on the enamel for 15 seconds and gently evaporated with air as suggested by the manufacturer. The brackets were then bonded with Transbond XT as in the first group. Group III: A new experimental self-etch primer EXL# 547 (3M ESPE, St. Paul, Minnesota, USA, was rubbed on the enamel for 10 seconds and left to stand for 20 seconds before it was air-dried and then light cured for 10 seconds. The brackets were then bonded as in groups I and II RESULTS: The present in vitro findings indicated that the shear bond strengths of the three groups were significantly different (P=0.018. Duncan multiple range tests indicated that Prompt L-Pop had a significantly lower (mean = 7.1 ± 4.4 MPa shear bond strength than both the new EXL# 547 self- etch primer (mean = 9.7 ± 3.7 MPa or phosphoric acid and the conventional adhesive system ( mean = 10.4 ± 2.8 MPa. CONCLUSIONS: The present results indicated that the newly introduced self-etch primers, containing both the enamel etchant and primer have the potential to be successfully used in bonding orthodontic brackets.

S. E. Bishara

2002-01-01

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Measurement of Orthodontic Bracket Tie Wing Elastic and Plastic Deformation by Arch Wire Torque Expression Utilizing an Optical Image Correlation Technique  

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Full Text Available Orthodontic lingual root movement (torque is an important aspect of treatment biomechanics and is typically achieved by torsion of a rectangular wire within the orthodontic bracket slot which introduces a force couple. The magnitude of the force moment achieved by wire torsion may be influenced by deformation of the orthodontic bracket. A device utilizing an optical image correlation technique has been developed to accurately quantify bracket slot dimensional changes during application of wire torsion. Simultaneous torque moment magnitude, degrees of wire twist, and bracket slot dimension data can be gathered. Bracket tie wing elastic deformation when loaded was demonstrated and plastic deformation was also observed with a single rotation of the wire.

Ryan A. Lacoursiere

2010-01-01

75

Orthodontic bracket designs and their impact on microbial profile and periodontal disease: A clinical trial  

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Aim: The aim of the present study was to compare the undisturbed plaque formation on teeth bonded with Preadjusted (Captain Ortho, Libral Traders, Mumbai, India) and Begg Brackets (Captain Ortho, Libral Traders, Mumbai, India) with nonbonded control sites via a de novo plaque growth over a period of 7 days. Materials and Methods: A clinical trial with the split-mouth design was set up enrolling 10 dental students. Within each subject sites with (Preadjusted) (P-site), Begg brackets (B-site) and control sites were followed. Plaque index and gingival index were recorded on days 3 and 7. Supra-gingival and sub-gingival plaque samples were taken from the brackets and the teeth on days 3 and 7, and were sent for aerobic and anaerobic culturing. The total number of bacterial colony forming units (CFU) was assessed for each sample using a colony counter. Tukeys and Dunnett test then statistically analyzed data. Results: The mean plaque index and gingival index increased on P-site and B-site on the third and 7th day. The shift from aerobic to anaerobic species was observed earlier in P-sites than in B-sites. The CFU were significantly higher for all sites on day 7 when compared with day 3. The aerobe/anaerobe CFU ratio was significantly lower in P-sites than in B-sites and then control showing an increase in the number of anaerobic species on the 3rd and 7th day (P < 0.05). Based on observed means, the mean difference was significant (P < 0.05). Conclusion: The present data suggest that Preadjusted brackets accumulated more plaque than Begg brackets. Bracket design can have a significant impact on bacterial load and on periodontal parameters.

Moolya, Nikesh N; Shetty, Arvind; Gupta, Neha; Gupta, Anvesha; Jalan, Vivek; Sharma, Rashmi

2014-01-01

76

Effect of fluoride solutions on the shear bond strength of orthodontic brackets  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese O objetivo deste estudo foi o de avaliar in vitro a resistência adesiva de bráquetes após o pré-tratamento do esmalte com diferentes soluções fluoretadas. Foram utilizados 48 incisivos bovinos hígidos recém-extraídos que foram aleatoriamente divididos em 4 grupos experimentais (n=12). CG (controle): [...] sem tratamento; FN: aplicação de flúor neutro por 4 min; FFA: aplicação de flúor fosfato acidulado (FFA) a 1,23% por 4 min; e VFS: aplicação de verniz de fluoreto de sódio a 5% por 6 h. Após o tratamento dos grupos, foi realizada a profilaxia do esmalte e os bráquetes foram fixados utilizando o compósito Transbond XT (3M), seguindo as especificações do fabricante. A resistência adesiva foi verificada através do teste de cisalhamento, realizado na Máquina de Ensaio Universal DL-2000 24 h após a fixação dos bráquetes. As superfícies dos dentes foram analisadas para verificação do índice de adesivo remanescente (IAR). Por meio dos testes estatísticos ANOVA e Tukey (?=5%), observou-se diferença estatisticamente significante entre os grupos estudados (p0,05). A análise dos escores do IAR revelou que grande parte das falhas ocorreram na interface esmalte-resina. Conclui-se que o tratamento do esmalte com FFA 1,23% e VFS a 5%, previamente à fixação de bráquetes ortodônticos, reduziu os valores de resistência adesiva ao cisalhamento Abstract in english The aim of this in vitro study was to evaluate the shear bond strength of brackets after pre-treatment with different fluoride solutions. This study used 48 freshly extracted sound bovine incisors that were randomly assigned to 4 experimental groups (n=12). CG: (control) without treatment; NF: 4 min [...] application of neutral fluoride; APF: application of 1.23% acidulated phosphate fluoride (APF) for 4 min; and SFV: application of 5% sodium fluoride varnish for 6 h. For each group, after surface treatment, prophylaxis of enamel and bracket bonding with Transbond XT composite resin (3M) were performed following the manufacturer's specifications. The shear bond strength was performed with a universal testing machine 24 h after fixing the brackets. The tooth surfaces were analyzed to verify the adhesive remnant index (ARI). Data were analyzed statistically by ANOVA and Tukey's test (?=0.05). There was statistically significant difference among the groups (p0.05). The analysis of ARI scores revealed that most failures occurred at the enamel-resin interface. It may be concluded that the pre-treatment of enamel with 1.23% APF and 5% SFV prior to fixing orthodontic brackets reduces shear bond strength values.

Gabriela da Rocha, Leódido; Hianna Oliveira, Fernandes; Mateus Rodrigues, Tonetto; Cristina Dupim, Presoto; Matheus Coêlho, Bandéca; Leily Macedo, Firoozmand.

77

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

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english 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.

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

78

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

Directory of Open Access Journals (Sweden)

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.

Hassan Isber

2011-02-01

79

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

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english 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.

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

2011-02-01

80

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

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese 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

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

 
 
 
 
81

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

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese 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

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

82

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

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese 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

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

2013-04-01

83

Effects of fluorosis on the shear bond strength of orthodontic brackets bonded with a self-etching primer.  

Science.gov (United States)

The aim of this study was to compare the shear bond strength (SBS) of brackets bonded to fluorosed and non-fluorosed teeth with self-etching primer (SEP) and phosphoric acid (PA). The study involved 40 mildly fluorosed [Thylstrup-Fejerskov (TFT) Index = 1-3] and 40 non-fluorosed human premolar teeth. The fluorosed and non-fluorosed teeth were randomly divided into two subgroups. In the first subgroup, 37 per cent PA was applied for 30 seconds and in the second, a SEP (Transbond Plus) was used. The brackets were bonded with light-cure adhesive paste (Transbond XT) and cured for 20 seconds. The SBSs were measured after 1000 thermocyclies. Two-way analysis of variance, Tukey's multiple comparison test, and Weibull analysis were used for the evaluation of SBS values. Bond failure locations were determined with the adhesive remnant index (ARI) and were compared with the Kruskal-Wallis and Mann-Whitney U-tests. The mean SBS was 9.01 MPa for the fluorosed teeth bonded with SEP. This value was significantly different from those of fluorosed teeth etched with PA (15.22 MPa) and non-fluorosed teeth conditioned with SEP (12.95 MPa) and PA (15.37 MPa). The ARI scores of the fluorosed teeth conditioned with SEP were significantly lower than those of non-fluorosed teeth conditioned with SEP or PA. The results of this in vitro study suggest that there are no differences in the SBS of orthodontic brackets between mildly fluorosed and non-fluorosed enamel etched with 37 per cent PA for 30 seconds. The SEP showed lower SBS values for orthodontic brackets bonded to mildly fluorosed enamel. The findings provide some evidence that routine clinical use of a SEP to bond brackets to mildly fluorosed teeth cannot be supported. PMID:20841314

Isci, Devrim; Sahin Saglam, Aynur Medine; Alkis, Huseyin; Elekdag-Turk, Selma; Turk, Tamer

2011-04-01

84

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

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english 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.

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

85

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

Directory of Open Access Journals (Sweden)

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.

Rebeca Di Nicoló

2010-03-01

86

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

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english 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.

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

87

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

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese 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, 3 [...] M/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). Abstract in english 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 na [...] mes, 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).

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

88

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

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese 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, 3 [...] M/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). Abstract in english 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 na [...] mes, 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).

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

2010-06-01

89

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

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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.

Luciane Macedo de Menezes

2010-06-01

90

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

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Full Text Available SciELO Brazil | Language: English Abstract in portuguese 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.

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

91

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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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.

Smita B. Patil

2014-01-01

92

Reconditioning of ceramic orthodontic brackets with an Er,Cr:YSGG laser.  

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It is now known that erbium lasers are effective in composite removal, but there is minimal information about their efficacy on recycling of ceramic brackets. This study, therefore, aimed to determine the percentage of remaining adhesive on the base and the shear bond strength of debonded ceramic brackets after being reconditioned by an Er,Cr:YSGG (erbium, chromium: yttrium-scandium-gallium-garnet) laser. Thirty premolars were divided into three groups, then bonded with mechanical retention ceramic brackets according to the bracket base conditions: (1) new brackets; (2) debonded brackets cleaned of adhesive with the Er,Cr:YSGG laser at 3.5 W; and (3) debonded brackets cleaned of adhesive with the Er,Cr:YSGG laser at 4 W. Before bonding, the percentage of remaining adhesive on the bases of reconditioned brackets was calculated by using stereomicroscopic images through an image processing software. The brackets were then tested in shear mode in a universal testing machine and the adhesive remnant index scores were determined. The percentage of remaining adhesive on the bases of brackets that were cleaned by the Er,Cr:YSGG laser at 4 W (3.1 %) was significantly lower than that of the 3.5-W laser group (5.9 %) (p = 0.03). No significant difference was found in bond strengths between the new and the reconditioned brackets (p = 0.19). The frequency of bond failure at the enamel-adhesive interface was lower in the laser-reconditioned brackets when compared to the new brackets. The application of Er,Cr:YSGG laser was efficient in removing adhesive from bases of debonded ceramic brackets because it produced comparable bond strengths to new brackets while reducing the risk of enamel damage during debonding. PMID:22585379

Ahrari, Farzaneh; Fekrazad, Reza; Kalhori, Katayoun A M; Ramtin, Mahshid

2013-01-01

93

Bacterial adhesion forces and biofilm prevention on orthodontic materials  

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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...

Mei, Li

2011-01-01

94

Shear bond strength of fluoride-releasing orthodontic bonding and composite materials.  

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Several fluoride-releasing bonding materials are available for orthodontic bracket placement. These are supposed to prevent white spot lesions during therapy. The objectives of this in vitro study were to evaluate the shear bond strength (SBS) and failure mode of a recently introduced fluoride-releasing adhesive, as well as the comparison with established orthodontic adhesives. Sixty bovine mandibular incisors were randomly allocated to three groups (n = 20): stainless steel brackets were bonded with Transbond Plus Color Change Adhesive, Transbond XT, or Light Bond. A universal testing machine was used to determine the SBS at a crosshead speed of 1 mm/minute. After debonding, the adhesive remnant index (ARI) was used to assess the adhesive remaining on the brackets. One-way analysis of variance comparing the three experimental groups showed no differences between the bonding systems for mean SBS (P = 0.27). ARI scores showed more residual adhesive on the teeth bonded with the Transbond systems (P < 0.01). As the fluoride-releasing bonding system provided sufficient mean bond strength in vitro (19.9 MPa), it may be used as an additional prophylactic measure in orthodontic therapy. However, the clinical effectiveness of its fluoride release may be questionable, as the amount of fluoride required from a bonding material to be caries preventive is still unknown. PMID:20080958

Pseiner, Bernhard Christian; Freudenthaler, Josef; Jonke, Erwin; Bantleon, Hans-Peter

2010-06-01

95

Influence of surface treatment on shear bond strength of orthodontic brackets  

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Full Text Available SciELO Brazil | Language: English Abstract in portuguese 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.

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

2013-06-01

96

Orthodontic materials research and applications: part 2. Current status and projected future developments in materials and biocompatibility.  

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The purpose of this 2-part opinion article was to project the developments expected to occur in the next few years in orthodontic materials research and applications. Part 1 reviewed developments in bonding to enamel. Part 2 looks at other orthodontic materials applications and explores emerging research strategies for probing the biological properties of materials. In the field of metallic brackets, expansion of the use of titanium alloys with improved hardness and nickel-free steels with better corrosion resistance and increased hardness is expected. Manufacturing techniques might be modified to include laser-welding methods and metal injection molding. Esthetic bracket research will involve the synthesis of high-crystallinity biomedical polymers with increased hardness and stiffness, decreased water sorption, and improved resistance to degradation. New plastic brackets might incorportate ceramic wings. Fiber-reinforced composite archwires, currently experimental, could soon be commercially available, and long-term applications of shape-memory plastics might become viable. Advancements in elastomeric materials will result in polymers with reduced relaxation, broader use of fluoride-releasing elastomers with decreased relaxation, and large-scale film coating of elastomers to decrease reactivity, water sorption, and degradation. Finally, biocompatibility assessments will incorporate testing of potential endocrinological action. New polymer formulations might be tested in adhesive and plastic bracket manufacturing, based on benzoic ring-free monomers to avoid the adverse effects of the estrogenic molecule bisphenol-A. PMID:17276868

Eliades, Theodore

2007-02-01

97

Effects of ultrasonic instrumentation with different scaler-tip angulations on the shear bond strength and bond failure mode of metallic orthodontic brackets  

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Objective To evaluate the effects of ultrasonic instrumentation with different scaler-tip angulations on the shear bond strength (SBS) and bond failure mode of metallic orthodontic brackets. Methods Adhesive pre-coated metallic brackets were bonded to 72 extracted human premolars embedded in autopolymerizing acrylic resin. The teeth were randomly divided into 3 groups (n = 24 each) to undergo no treatment (control group) or ultrasonic instrumentation with a scaler-tip angulation of 45° (45°-angulation group) or 0° (0°-angulation group). SBS was tested in a universal testing machine, and adhesive remnant index (ARI) scores were recorded. The Kruskal-Wallis test and Mann-Whitney U-test were used for statistical analysis. Results The control group had a significantly higher mean SBS value than the treated groups, which showed no significant differences in their mean SBS values. The ARI scores were not significantly different among the groups. Conclusions Ultrasonic instrumentation around the bracket base reduces the SBS of metallic orthodontic brackets, emphasizing the need for caution during professional oral hygiene procedures in orthodontic patients. The scaler-tip angulation does not influence the SBS reduction and bond failure mode of such brackets. PMID:24511515

Incerti Parenti, Serena; Ippolito, Daniela Rit; Gatto, Maria Rosari; Luigi, Checchi

2014-01-01

98

An evaluation of slot size in orthodontic brackets--are standards as expected?  

Science.gov (United States)

The slots of five upper left central incisor brackets from 11 commercially available bracket systems (3M Unitek, Monrovia, Calif: Twin Torque Roth, Clarity MBT, and Victory Series MBT; Dentarum, Pforzheim, Germany: Discovery Roth (0.56 mm) and Elegance Plastic Roth; Forestadent, Pforzheim, Germany: Mini Mono MBT; TP LaPorte, Indiana: Nu-Edge Roth and Mxi Advant-Edge Roth; Ormco Corp., Orange, Calif: Damon II SL Roth; Ortho Organizers, San Marcos, Calif: Elite Mini Opti-MIM Roth and Elite Mini Opti-MIM MBT) were measured in the 0.022-inch (0.5588 mm) dimension. Measurements were taken after operator calibration, and a digital readout was produced. Results indicate that all bracket slots are oversized. Three bracket systems slots (Twin Torque, Clarity, and Mini Mono) were within 5% (+/-1.08, 1.655, 1.75) of their stated dimensions with essentially parallel slot walls. The Elegance Plastic slot was parallel sided but oversized by 12% (+/-1.15). The geometry of bracket slots was also variable. The Victory Series slot was slightly divergent with the top oversized by 6% (+/-1.035). The Nu-Edge slot was divergent and slot top oversized by 14% (+/-1.32). The Mxi Advant-Edge, Damon II SL, Elite Mini Opti-MIM Roth, and MBT were all convergent, and the base of the Damon slot was oversized by 17% (+/-1.79). The Discovery bracket was convergent, and the slot base was oversized by 24% (+/-1.255), which was the largest recorded variance. This bracket also had a 7% difference between the widths of the slot top and the base. Inaccurate machining of bracket slot dimensions and the use of undersized archwires may directly and adversely affect three-dimensional tooth positioning. PMID:15387021

Cash, A C; Good, S A; Curtis, R V; McDonald, F

2004-08-01

99

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

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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-Chromium, 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 i...

Mônica Pereira Saporeti; Enio Tonani Mazzieiro; Wisley Falcco Sales

2012-01-01

100

Evaluation of self-etching adhesive and Er:YAG laser conditioning on the shear bond strength of orthodontic brackets.  

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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

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

 
 
 
 
101

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)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese 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

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

102

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)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese 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

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

2011-08-01

103

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

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese 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.

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

2005-06-01

104

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

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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.

André Moreira Mattos

2006-10-01

105

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

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese 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.

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

106

Are torque values of preadjusted brackets precise?  

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Full Text Available SciELO Brazil | Language: English Abstract in english 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.

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

107

Are torque values of preadjusted brackets precise?  

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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.

Alessandra Motta Streva

2011-08-01

108

Properties of Composite Materials Used for Bracket Bonding  

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Full Text Available SciELO Brazil | Language: English Abstract in portuguese 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

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

109

An overview of orthodontic material degradation in oral cavity  

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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.

Chaturvedi T

2010-01-01

110

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

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Full Text Available SciELO Brazil | Language: English Abstract in english 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, parti [...] cipated 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.

Solange Machado, Mota; Carla, Enoki; Izabel Yoko, Ito; Ana Maria, Elias; Mírian Aiko Nakane, Matsumoto.

111

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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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 composite-to-enamel bond. However, the efficacy of antioxidants in increasing the SBS of brackets bonded using resin-modified glass-ionomer 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 magni-fication. Data were analyzed using Mann-Whitney U test, one- and independent-samples t-test, and Fisher’sexact 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 dif-ference 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 de-serves further studies. PMID:22991638

Khosravanifard, Behnam; Rakhshan, Vahid; Araghi, Solmaz; Parhiz, Hadi

2012-01-01

112

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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Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese 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 fi [...] cam 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. Abstract in english 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.

Adriano Marotta, Araújo; Fernanda de Oliveira e, Silva; Weber José da Silva, Ursi; Eduardo César, Werneck.

2009-12-01

113

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

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Full Text Available SciELO Brazil | Language: English Abstract in portuguese 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.

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

2012-12-01

114

Clinical evaluation of the failure rates of metallic brackets  

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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. Brackets 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<0.05. There was no statistically significant difference between the dental arches (upper and lower, between the dental arch sides (right and left, and among the quadrants. CONCLUSIONS: The largest number of bracket failures occurred with Orthodontic Concise and Transbond XT without primer systems and few bracket failures occurred with conventional Transbond XT and Transbond XT+TPSEP. More bracket failures were observed in the posterior region compared with the anterior region.

Fábio Lourenço Romano

2012-04-01

115

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

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese 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 (p Abstract in english AIM: 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 tim [...] e 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

André Moreira, Mattos; Jonas, Capelli Júnior.

2006-10-01

116

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  

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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.

Roberta Buzzoni

2011-08-01

117

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)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese 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.

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

118

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)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese 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.

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

2008-08-01

119

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)

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.

Leonardo de Aquino Fleischmann

2008-08-01

120

The role of friction in orthodontics  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english INTRODUCTION: Sliding mechanics is widely used during orthodontic treatment. One of the disadvantages of this mechanics is the friction generated at the bracket/archwire interface, which may reduce the amount of desired orthodontic movement obtained. Due to the application and great acceptance of th [...] is type of mechanics, the role of friction in Orthodontics has been of interest for both clinicians and scientists. OBJECTIVE: Therefore, this article discussed how friction affects orthodontic tooth movement, with an approach to its clinical implications as well as the evolution of dental materials and its properties regarding resistance to sliding.

Mariana Ribeiro, Pacheco; Wellington Corrêa, Jansen; Dauro Douglas, Oliveira.

 
 
 
 
121

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)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese 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.

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

122

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)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese 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.

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

2013-12-01

123

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

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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.

Tatiana Kelly da Silva Fidalgo

2011-02-01

124

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)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese 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.

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

2014-06-01

125

Clinical evaluation of the failure rates of metallic brackets  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english 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

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

126

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

Science.gov (United States)

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. PMID:25025564

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

2014-01-01

127

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

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english 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

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

2011-02-01

128

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

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english 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

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

129

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

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english 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.

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

2014-06-01

130

A bracket design proposal for the first molar  

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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.

Roberto Scalon

2010-07-01

131

Rapid debonding of polycrystalline ceramic orthodontic brackets with an Er:YAG laser: an in vitro study.  

Science.gov (United States)

The usefulness of erbium-doped yttrium aluminum garnet laser irradiation for debonding ceramic brackets is assessed using a single laser pulse. Damon Clear brackets were chosen for their 85% transmission of 2.94 ?m radiation and were bonded to 20 human third molars using the Blugloo adhesive system. Laser parameters comprised of 600 mJ pulse energy with 800 ?s duration, 1.3 mm fiber tip. Light microscopy was used to assess Adhesive Remnant Index (ARI) scores, and scanning electron microscope (SEM) images were taken of the cross-section of the enamel-adhesive interface. Nineteen brackets (95%) were successfully debonded with a single laser pulse, while one bracket (5%) required eight pulses for debonding. For all teeth, the SEM analysis showed no signs of damage to the enamel, and ARI scores of three were observed, supporting the result that the laser effect is confined in the adhesive. The presented laser parameters are able to rapidly debond suitable brackets. The debonding mechanism was concluded to be thermomechanical ablation for single pulse debonding. PMID:23525867

Mundethu, Ambili Roselina; Gutknecht, Norbert; Franzen, Rene

2014-09-01

132

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

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese 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).

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

2007-12-01

133

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)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese 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.

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

134

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)

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.

Camila Belo Falcão

2009-06-01

135

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)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese 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.

Carla, Giannini; Paulo Afonso Silveira, Francisconi.

136

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

Directory of Open Access Journals (Sweden)

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. METODOLOGIA: 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.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 after 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.

Carla Giannini

2008-06-01

137

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

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese 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

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

2013-04-01

138

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

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese 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

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

139

Wear comparison of thermoplastic materials used for orthodontic retainers.  

Science.gov (United States)

Clear thermoplastic retainers are an alternative to fixed lingual retainers and removable Hawley appliances. However, thermoplastic retainers have demonstrated poor wear resistance and durability after only a few months of use. In this study, a simulated wear device was used to compare the wear of different thermoplastic materials used for orthodontic retainers. Three thermoplastic products were evaluated: C+ (Raintree Essix, New Orleans, La),.040-in Invisacryl C (Great Lakes Orthodontics, Towanda, NY), and.040-in TR sheet material (Bay Dental Direct, Bay City, Mich). Twenty specimens were fabricated for each group. The specimens were vacuum thermoformed according to the manufacturers' recommendations and subjected to wear for 1000 cycles in a wear apparatus with steatite ceramic abraders. Depth of wear was determined by surface profilometry. The maximum peak-to-valley measurement was recorded for each specimen. Mean wear (SD) in microns was as follows: C+, 5.9 (2.4); Invisacryl C, 6.1 (2.6); and TR, 1.6 (0.9). One-way analysis of variance detected a significant difference between groups (P .05). PMID:12970663

Gardner, Gary D; Dunn, William J; Taloumis, Louis

2003-09-01

140

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  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese 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 gr [...] upos, 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. Abstract in english 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.

Carla D' Agostini, Derech; Juliana da Silva, Pereira; Margareth Maria Gomes de, Souza.

 
 
 
 
141

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  

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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.

Carla D'Agostini Derech

2008-06-01

142

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  

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Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese 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 gr [...] upos, 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. Abstract in english 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.

Carla D' Agostini, Derech; Juliana da Silva, Pereira; Margareth Maria Gomes de, Souza.

2008-06-01

143

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  

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Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese 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.

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

2010-06-01

144

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  

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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.

A. C Dalvi

2010-06-01

145

Scanning electron microscopic examination of enamel surface after fixed orthodontic treatment: In-vivo study  

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Full Text Available Introduction. Therapy with fixed orthodontic appliances starts with bracket bonding and ends with debonding of brackets, leaving enamel surface varied. Objective. The aim of this pilot study was to examine enamel surface before and after debonding of orthodontic brackets by the use of scanning electron microscopy (SEM. Methods. Epoxy replicas of four patients’ premolars indicated for therapy with fixed orthodontic appliances were made and brackets were bonded to their teeth with a different adhesives (Enlight, No-mix, Fuji Ortho LC and Heliosit Orthodontic (n=4. Two months later, brackets on premolars were debonded and amounts of adhesive left on the tooth surfaces and the bracket bases were evaluated with the adhesive remnant index (ARI. After resin removal, epoxy replicas were made and the surface of premolars was evaluated with the enamel surface index (ESI. All replicas of premolars (n=32 were prepared for SEM examination and compared under different magnifications. Tooth damage was estimated based on correlation between ARItooth and ESI. Results. Pearson’s ?2 test showed no significant differences between ARItooth and ARIbracket of four materials used. Nonparametric correlations showed significant differences between ARItooth and ARIbracket, ESI and ARItooth, and between ESI and ARIbracket. Increasing of ARItooth is followed with the descent of ARIbracket and the ascent of ESI. Multivariate regression analysis showed a significant correlation between ESI and ARItooth. Conclusion. Most bond failures took place at enamel-adhesive interface. ARItooth was a predictor to enamel surface damage. The type of material did not affect enamel surface damage.

Sessa Tijana

2012-01-01

146

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  

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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.

Lilian Maria Brisque Pignatta

2009-02-01

147

Comparison of the effect of hydrogel and solution forms of sodium ascorbate on orthodontic bracket-enamel shear bond strength immediately after bleaching: An in vitro study  

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Full Text Available Aim: This study compared the effects of hydrogel and solution forms of sodium ascorbate (SA with two different application times on bracket bond strength subsequent to bleaching. Materials and Methods: A total of 72 sound premolars were randomly divided into six groups (n = 12: An unbleached control group (group one and five experimental groups of carbamide peroxide. Specimens in group two were bonded immediately after bleaching; specimens in groups three and four were bleached, then treated with SA solution for ten minutes and three hours, respectively, and then bonded. In groups five and six, SA hydrogel was used and the specimens were prepared similar to groups three and four, respectively. Following debonding, bond strengths were recorded in MPa. To evaluate the amount of resin left on the enamel surfaces, adhesive remnant index (ARI scores were used. Statistical Analysis: The bond strength data were analyzed with ANOVA and pairwise comparisons were made by Tukey test. The ARI data were subjected to Kruskal-Wallis test and two-by-two comparisons were made by the Mann-Whitney U test. Results: There were significant differences in bond strengths between the groups ( P < 0.0005. However, the differences between groups three, four, five and six were not significant. Furthermore, there were no significant differences between group one and groups four and six, whereas the differences between the other groups were significant ( P < 0.05. Regarding ARI, there were significant differences among the groups ( P = 0.004. Conclusion: Bleaching significantly decreased the bracket bond strength. Compromised bonding was reversed with a three-hour application of both forms of SA.

Kimyai Soodabeh

2010-01-01

148

Friction coefficients and wear rates of different orthodontic archwires in artificial saliva.  

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The aim of this paper is to analyze the influence of the nature of the orthodontic archwires on the friction coefficient and wear rate against materials used commonly as brackets (Ti-6Al-4V and 316L Stainless Steel). The materials selected as orthodontic archwires were ASI304 stainless steel, NiTi, Ti, TiMo and NiTiCu. The array archwire's materials selected presented very similar roughness but different hardness. Materials were chosen from lower and higher hardness degrees than that of the brackets. Wear tests were carried out at in artificial saliva at 37 °C. Results show a linear relationship between the hardness of the materials and the friction coefficients. The material that showed lower wear rate was the ASI304 stainless steel. To prevent wear, the wire and the brackets have high hardness values and in the same order of magnitude. PMID:23440428

Alfonso, M V; Espinar, E; Llamas, J M; Rupérez, E; Manero, J M; Barrera, J M; Solano, E; Gil, F J

2013-05-01

149

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)

150

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

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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

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

2014-08-01

151

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

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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 length 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<0.05, Bonferroni post hoc test were found in each joint configuration. The highest fracture strength means were observed for laser welding with filling material and 3 mm joint length (998 N. Using filling materials, there was a clear tendency to higher mean values of fracture strength in TIG and laser welding. However, statistically significant differences were found only in the 9-mm long joints (p<0.05, Bonferroni post hoc test. In conclusion, the fracture strength of welded joints was positively influenced by the additional use of filling material. TIG welding was comparable to laser welding except for the impossibility of joining orthodontic wire with orthodontic band.

Jens Johannes Bock

2008-10-01

152

Comparison of bond strength of lingual brackets under different composite base forming method.  

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Full Text Available AIM: To investigate the shear bond strength of indirectly bonded Ormco lingual brackets, using different composite bracket base preparation. DESIGN: Prospective random study SETTING: This study was conducted at Department of Orthodontics of the School of Dentistry of the University of Istanbul in 2004 MATERIAL AND METHODS: Twenty mandibular premolars extracted for orthodontic purposes were selected and divided into two equal groups. Group 1: (n=10 1 mm composite base was constructed directly on the intact bracket base. Group 2: (n=10 the bracket bases were first sandblasted with a microetcher using 50 ?m aluminium oxide particles and then the 1 mm composite base was constructed. INTERVENTION: The universal Lloyd testing instrument used for the application of shear forces. MAIN OUTCOME MEASURES: Results were compared statistically using analysis of variance and chi-square tests. RESULTS: The mean of shear bond strength test was 9.46±0.78 MPa and 12.11±0.82 MPa for group 1 and group 2 respectively. The difference was found to be statistically significant (P<0.001. The analysis of variance demonstrated that there were also statistically significant differences in adhesive remnant index (ARI scores between the groups (P<0.001. CONCLUSIONS: Sandblasting of the bracket bases increased the shear bond strength and the redundant between the bracket and the composite base.

Burak Aksu

2005-01-01

153

Comparative study on direct and indirect bracket bonding techniques regarding time length and bracket detachment  

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Full Text Available SciELO Brazil | Language: English Abstract in portuguese OBJETIVO: avaliar o tempo necessário para realização da colagem de braquetes pelas técnicas direta (CDB) e indireta (CIB), mensurando o tempo despendido entre a parte laboratorial (CIB) e a parte clínica (CDB e CIB), e a prevalência de descolamentos durante o período de observação de 24 semanas. MÉT [...] ODOS: dezessete pacientes (7 homens e 10 mulheres), com idade média de 21 anos, com necessidade de tratamento ortodôntico, foram selecionados para participar desse estudo. Foram utilizados um total de 304 braquetes, sendo que 151 foram colados pela técnica de CDB e 153 pela CIB, com o mesmo tipo de braquete e material de colagem. Os dados foram submetidos ao teste não paramétrico de Wilcoxon, com significância de 5%. RESULTADOS: o tempo total para realização da CIB foi maior em relação à CDB (p Abstract in english OBJECTIVE: The aim of this study was to assess the time spent for direct (DBB - direct bracket bonding) and indirect (IBB - indirect bracket bonding) bracket bonding techniques. The time length of laboratorial (IBB) and clinical steps (DBB and IBB) as well as the prevalence of loose bracket after a [...] 24-week follow-up were evaluated. METHODS: Seventeen patients (7 men and 10 women) with a mean age of 21 years, requiring orthodontic treatment were selected for this study. A total of 304 brackets were used (151 DBB and 153 IBB). The same bracket type and bonding material were used in both groups. Data were submitted to statistical analysis by Wilcoxon non-parametric test at 5% level of significance. RESULTS: Considering the total time length, the IBB technique was more time-consuming than the DBB (p

Jefferson Vinicius, Bozelli; Renato, Bigliazzi; Helga Adachi Medeiros, Barbosa; Cristina Lucia Feijo, Ortolani; Francisco Antonio, Bertoz; Kurt, Faltin Junior.

154

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  

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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.

Marcia Cristina Rastelli

2010-06-01

155

Development of an orthodontic elastic material using EMA-based resin combined with 1-butanol.  

Science.gov (United States)

For the development of new orthodontic elastic material, 1-butanol was added to PEMA-TA/HX resin. In the present study, basic experiments to reveal the mechanical properties of the materials were conducted. FT-IR spectroscopy showed that addition of 1-butanol did not cause any chemical changes to the PEMA-TA/HX resin. After addition of 1-butanol to PEMA-TA/HX resin, the modulus of elasticity, instantaneous modulus elasticity, retarded elasticity and viscosity were lowered in a concentration-dependent manner, whereas the elastic strain was increased in a concentration-dependent manner. Moreover, on the application of heat a shape-memory effect was observed. These results suggest that the modulus of elasticity of this material can be adjusted. Additionally, this material has the ability to restore force as a function of its shape-memory effect in cases of plastic deformation at the insertion of appliances. This new orthodontic elastic material has the potential to be clinically effective in orthodontic treatment. PMID:21946487

Masuda, Takehiro; Miyazawa, Ken; Ueda, Naoya; Hata, Yuki; Kawai, Tatsushi; Goto, Shigemi

2011-01-01

156

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  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese 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 (p Abstract in english The 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 c [...] onduced 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

Edgard Norões R. da, Matta; José de Albuquerque Calasans, Maia; Orlando, Chevitarese.

2005-04-01

157

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  

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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.

Edgard Norões R. da Matta

2005-04-01

158

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)

159

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

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Full Text Available SciELO Brazil | Language: English Abstract in english 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

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

160

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

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese 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. Abstract in english 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. [...

Luciane Macedo de, Menezes; Maria Perpétua Mota, Freitas; Tatiana Siqueira, Gonçalves.

 
 
 
 
161

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  

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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.

Carolina Freire de Carvalho Calabrich

2010-08-01

162

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  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese 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. Abstract in english 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.

Carolina Freire de Carvalho, Calabrich; Marcelo de Castellucci e, Barbosa; Maria Regina Lorenzetti, Simionato; Rogério Frederico Alves, Ferreira.

163

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

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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.

Shiva Alavi

2010-01-01

164

Antimicrobial and fluoride release capacity of orthodontic bonding materials  

Science.gov (United States)

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. PMID:24037071

CALDEIRA, Erika Machado; OSORIO, Amanda; OBEROSLER, Edna Lucia Couto; VAITSMAN, Delmo Santiago; ALVIANO, Daniela Sales; NOJIMA, Matilde da Cunha Goncalves

2013-01-01

165

Staining of esthetic brackets by plaque disclosing solutions  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english 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.

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.

166

Antimicrobial and fluoride release capacity of orthodontic bonding materials  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english 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.

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

2013-07-01

167

Antimicrobial and fluoride release capacity of orthodontic bonding materials  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english 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.

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

168

Effect of archwire size and material on the resistance to sliding of self-ligating brackets with second-order angulation in the dry state.  

Science.gov (United States)

When paired with a particular self-ligating bracket design, the material and the geometric characteristics of an archwire influence its resistance to sliding. Four designs of self-ligating brackets (1 with a slide, 3 with clips) were coupled with 5 types of archwires: 14-mil round austenitic nickel-titanium, 16 x 22-mil rectangular austenitic nickel-titanium, 19 x 25-mil rectangular austenitic nickel-titanium, 19 x 25-mil rectangular martensitic nickel-titanium, and 19 x 25-mil rectangular stainless steel. The resistance to sliding (RS) of each archwire-bracket couple was measured at second-order angles between -9 degrees and 9 degrees. Interbracket distances of 8 and 18 mm between the test bracket and the adjacent brackets mimicked closure of a premolar extraction. When clearance exists, the RS is negligible for self-ligating brackets with slides coupled to any size of wire as well as for those with clips when coupled to wires that do not contact the clip. Once the wire attains a certain size and contacts the clip, the RS depends on the archwire size, the bracket design, and the materials of the couple. When coupled with the 16 x 22-mil wire, the brackets with clips applied normal forces ranging from a low of 5.6 centi-Newtons (cN) (1 cN = 1 g) to a high of 230 cN. When clearance disappears, the RS increased proportionally with the second-order angle. The 19 x 25-mil stainless steel wires, which were the most stiff, increased at rates between 75 and 84 cN/degree; the 14-mil austenitic nickel-titanium wires, which were the least stiff, increased at rates from 2.6 to 5.4 cN/degree. The treatment objectives for a particular patient at a specific stage should determine the appropriate archwire-bracket combination. PMID:12226612

Thorstenson, Glenys A; Kusy, Robert P

2002-09-01

169

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)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese 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

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

170

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)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese 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

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

2010-06-01

171

Experiense with remineraling means in patients undergoing orthodontic treatment  

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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

Stepanova Ye.A.

2011-03-01

172

Analysis of mesiodistal angulations of preadjusted brackets  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english 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

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

2014-08-21

173

Evaluation of failure characteristics and bond strength after ceramic and polycarbonate bracket debonding: effect of bracket base silanization.  

Science.gov (United States)

The objectives of this study were to evaluate the effect of silanization on the failure type and shear-peel bond strength (SBS) of ceramic and polycarbonate brackets, and to determine the type of failure when debonded with either a universal testing machine or orthodontic pliers. Silanized and non-silanized ceramic and polycarbonate brackets (N = 48, n = 24 per bracket type) were bonded to extracted caries-free human maxillary central incisors using an alignment apparatus under a weight of 750 g. All bonded specimens were thermocycled 1000 times (5-55 degrees C). Half of the specimens from each group were debonded with a universal testing machine (1 mm/minute) to determine the SBS and the other half by an operator using orthodontic debonding pliers. Failure types of the enamel surface and the bracket base were identified both from visual inspection and digital photographs using the adhesive remnant index (ARI) and base remnant index (BRI). As-received ceramic brackets showed significantly higher bond strength values (11.5 +/- 4.1 MPa) than polycarbonate brackets [6.3 +/- 2.7 MPa; (P = 0.0077; analysis of variance (ANOVA)]. Interaction between bracket types and silanization was not significant (P = 0.4408). Silanization did not significantly improve the mean SBS results either for the ceramic or polycarbonate brackets (12.9 +/- 3.7 and 6.3 +/- 2.7 MPa, respectively; P = 0.4044; two-way ANOVA, Tukey-Kramer adjustment). There was a significant difference between groups in ARI scores for ceramic (P = 0.0991) but not polycarbonate (P = 0.3916; Kruskall-Wallis) brackets. BRI values did not vary significantly for ceramic (P = 0.1476) or polycarbonate (P = 0.0227) brackets. Failure type was not significantly different when brackets were debonded with a universal testing machine or with orthodontic debonding pliers. No enamel damage was observed in any of the groups. PMID:18209212

Ozcan, M; Finnema, K; Ybema, A

2008-04-01

174

The effect of Teflon coating on the resistance to sliding of orthodontic archwires.  

Science.gov (United States)

Teflon is an anti-adherent and aesthetic material. The aim of this study was to evaluate, in vitro, the influence of Teflon coating on the resistance to sliding (RS) of orthodontic archwires. For this purpose, Teflon-coated archwires were examined using frictional resistance tests by means of a universal testing machine and compared with conventional uncoated wires. Twelve types of archwires with round and rectangular sections (0.014, 0.018, and 0.018 × 0.025 inches) and of different materials (stainless steel and nickel-titanium) were tested with two passive self-ligating brackets (SmartClip™ and Opal(®)) and one active self-ligating bracket (Quick(®)). Each archwire-bracket combination was tested 10 times under 8 simulated clinical scenarios. Statistical comparisons were conducted between the uncoated and Teflon-coated archwires using Wilcoxon and Mann-Whitney tests, and linear regression analysis. For all bracket-archwire combinations, Teflon-coated archwires resulted lower friction than the corresponding uncoated archwires (P < 0.01). The results showed that Teflon coating has the potential to reduce RS of orthodontic archwires. PMID:21478301

Farronato, Giampietro; Maijer, Rolf; Carìa, Maria Paola; Esposito, Luca; Alberzoni, Dario; Cacciatore, Giorgio

2012-08-01

175

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

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english 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

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

2013-07-01

176

Cytomorphometric analysis for Metal Bracket Effects on Human Buccal Mucosa  

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Full Text Available Objective: To find out effect of metal brackets on the epithelial cells of the buccal mucosa as compared to normal mucosa without any brackets. Patients and Methods: Oral mucosal smears were obtained for patients visited for orthodontic treatment using a cytobrush. The study group consisted of P1: patients with no brackets, P2: 60 days after placement of metal brackets, P3: 30 days after removal of brackets. 30 individuals of both sexes who are undergoing fixed appliance theropy with bonded brackets were selected. With the use of exfoliative cytology, morphometric and morphologic changes in buccal mucosa cells adjacent to these brackets were determined and were compared at three points. Results: A decrease in nuclear area and an increase in cytoplasmic area occurred in the buccal mucosa cells adjacent to the brackets at P2 . At P3, this altered morphometry persisted only in cells adjacent to the metal brackets, although to a lesser degree than at P2 . A greater decrease in nuclear area was noted in cells adjacent to the metal brackets than in those for patients P1 . At all time points, smears of cells appeared normal or normal with some inflammatory changes. Conclusion: Placement of metal brackets in the buccal cavity induces cellular alterations. These alterations do not suggest malignancy.

Santosh kumar Goje

2010-04-01

177

Shear bond strength of new and recycled brackets to enamel.  

Science.gov (United States)

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 were 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-microm 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<0.05). In conclusion, the outcomes of this study showed that bracket recycling using 90-microm aluminum oxide particle air-abrasion was efficient and technically simple, and might provide cost reduction for orthodontists and patients alike. PMID:16721464

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

2006-01-01

178

[Enamel cracks: influence of orthodontic process].  

Science.gov (United States)

The presence of enamel cracks is not only due to the removal process. It is all the stages before that we need to consider. 1. The presence of risks factors before the treatment (cracks, trauma...) have to be explained to the patient and recorded. 2. The choice of bracket placement: the buccal side is responsible for less cracks than the lingual one. 3. Ceramic brackets need higher debonding forces than metal ones; metal reinforced orthodontic ceramic brackets could be an interesting approach. 4. CVIMR could be better than classic bonds. 5. In case of multiple rebondings, it is better not to etch enamel again but only to level the resin left on tooth surface. 6. Alternatives to removing brackets by pliers are studied, especially for the removal of ceramic brackets to thwart the high debonding force problem : heat, laser... PMID:25158747

Bernard-Granger, Chloé; Gebeile-Chauty, Sarah

2014-09-01

179

Laboratory evaluation of modern plastic brackets.  

Science.gov (United States)

The aim of the study was to evaluate some properties of modern orthodontic plastic brackets. Seven bracket brands [Aesthetik-Line (AL), Avalon (AV), Brillant (BR), Elegance (EL), OrthoFlex (OF), Silkon Plus (SL), and Spirit MB (SP)] were included in the study. The properties tested were chemical composition, base morphology, slot roughness, Vickers hardness (VH), and shear bond strength (SBS) with enamel.According to the results, the brackets were composed of polyurethane (AV and OF), polyoxymethylene (BR), and Ca-Al-silicate fibre glass-reinforced polycarbonate (AL, EL, SL, and SP). Metallic slots were composed of austenitic stainless steel (EL and SP) and Ag-Cu alloy (AV). The base morphology exhibited distinct designs, employing parallel retentive canals (AV, EL, and OF) or round-angled square protrusions with major retentive elements (AL, BR, and SP) or a combination of both (SL). The SP metallic slot demonstrated the lowest Sz values. No significant differences were found in VH among the brackets before water immersion (19.6-16.9 VH). After 12 weeks immersion, the brackets showed a significant hardness reduction (16.6-12.9 HV). SBS ranged between 111 and 193 N (8-14 MPa) for all brackets, except from SP (59 N/5 MPa). The predominant failure mode was mixed adhesive and cohesive. Most of the plastic brackets presented a base structure capable of adequate bonding to enamel, regardless of their differences in composition. Slot roughness showed differences among groups. All the brackets demonstrated plasticization after prolonged water storage. PMID:21750238

Ali, Omar; Makou, Margarita; Papadopoulos, Triantafillos; Eliades, George

2012-10-01

180

Characterization and cytotoxicity of ions released from stainless steel and nickel-titanium orthodontic alloys.  

Science.gov (United States)

The purpose of this study was to qualitatively and quantitatively characterize the substances released from orthodontic brackets and nickel-titanium wires and to comparatively assess the cytotoxicity of the ions released from these orthodontic alloys. Two full sets of stainless steel brackets of 20 brackets each (weight 2.1 g) and 2 groups of 0.018 x 0.025 Ni-Ti archwires of 10 wires each (weight 2.0 g) were immersed in 0.9% saline solution for a month. The immersion media were analyzed with inductively coupled plasma-atomic emission spectroscopy (ICP-AES), and the ionic content was statistically analyzed with 1-way analysis of variance (ANOVA). Human periodontal ligament fibroblasts and gingival fibroblasts were exposed to various concentrations of the 2 immersion media; nickel chloride was used as a positive control for comparison purposes. The cytotoxic or cytostatic activity of the media was investigated with the MTT and the DNA synthesis assays. The results of the cytotoxicity assay were analyzed with 2-way ANOVA and the Tukey test with solution and concentration variants as discriminating variables (alpha=0.05). The results indicated no ionic release for the nickel-titanium alloy aging solution, whereas measurable nickel and traces of chromium were found in the stainless steel bracket-aging medium. Concentrations of the nickel chloride solution greater then 2 mM were found to reduce by more than 50% the viability and DNA synthesis of fibroblasts; however, neither orthodontic materials-derived media had any effect on the survival and DNA synthesis of either cells. PMID:14718875

Eliades, Theodore; Pratsinis, Harris; Kletsas, Dimitris; Eliades, George; Makou, Margarita

2004-01-01

 
 
 
 
181

Shear bond strength of metallic brackets: influence of saliva contamination  

Directory of Open Access Journals (Sweden)

Full Text Available OBJECTIVE: To evaluate the influence of saliva contamination on shear bond strength and the bond failure pattern of 3 adhesive systems (Transbond XT, AdheSE and Xeno III on orthodontic metallic brackets bonded to human enamel. MATERIAL AND METHODS: Seventy-two permanent human molars were cut longitudinally in a mesiodistal direction, producing seventy-two specimens randomly divided into six groups. Each system was tested under 2 different enamel conditions: no contamination and contaminated with saliva. In T, A and X groups, the adhesive systems were applied to the enamel surface in accordance with manufacturer's instructions. In TS, AS and XS groups, saliva was applied to enamel surface followed by adhesive system application. The samples were stored in distilled water at 37ºC for 24 h, and then tested for shear bond strength in a universal testing machine (Emic, DL 2000 running at a crosshead speed of 1 mm/min. After bond failure, the enamel surfaces were observed under an optical microscope at 40x magnification. RESULTS: The control and contaminated groups showed no significant difference in shear bond strength for the same adhesive system. However, shear bond strength of T group (17.03±4.91 was significantly higher than that of AS (8.58±1.73 and XS (10.39±4.06 groups (p<0.05. Regarding the bond failure pattern, TS group had significantly higher scores of no adhesive remaining on the tooth in the bonding area than other groups considering the adhesive remnant index (ARI used to evaluate the amount of adhesive left on the enamel. CONCLUSIONS: Saliva contamination showed little influence on the 24-h shear bond strength of orthodontic brackets.

Luciana Borges Retamoso

2009-06-01

182

Comparative study of frictional forces generated by NiTi archwire deformation in different orthodontic brackets: In vitro evaluation / Estudo comparativo da força de atrito produzida pela deformação de arco NiTi em diferentes braquetes ortodônticos: avaliação in vitro  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese OBJETIVO: o objetivo desse trabalho foi comparar as forças de atrito entre fios NiTi 0,014" (Aditek) com deformações horizontais de 4mm, e braquetes com diferentes sistemas de ligação dos arcos. MÉTODOS: foram testados 4 tipos de braquetes autoligáveis (Damon MX, Easy Clip, Smart Clip e In-Ovation), [...] um braquete triplo (Synergy) e um braquete gêmeo com amarrilho 8 (Tecnident). Como grupo controle, foi utilizado braquete gêmeo com ligadura elástica convencional (Morelli). Foram executadas 10 repetições em cada combinação arco/braquete. As forças de atrito foram medidas em máquina de tração universal Instron, com velocidade de 3mm/minuto e deslocamento total de 6mm. Para análise estatística, usou-se a ANOVA e o Teste de Comparações Múltiplas de Dunnett. RESULTADOS: as forças de atrito por deformação do fio se mostraram crescentes na seguinte ordem: Synergy, Damon, amarrilho 8, Easy Clip, In-Ovation, Smart-Clip e ligadura convencional. As diferenças entre todos os grupos foram estatisticamente significantes, com exceção do Amarrilho 8 em relação aos grupos Damon e Easy Clip. CONCLUSÃO: em relação à ligadura convencional, todos os sistemas de fechamento das canaletas testados são eficientes em reduzir a força de atrito, porém, tal redução varia significativamente de acordo com o sistema de fechamento da canaleta selecionado. Abstract in english INTRODUCTION: The purpose of this study was to compare the frictional forces between 0.014-in NiTi wires (Aditek) with 4 mm horizontal deflection and brackets with different archwire ligation systems. METHODS: Four types of self-ligating brackets (Damon MX, Easy Clip, Smart Clip and In-Ovation), a t [...] riple bracket (Synergy) and a twin bracket with 8-shaped ligature (Tecnident) were tested. Twin brackets with conventional elastomeric ligatures (Morelli) were used as control group. Tests were repeated 10 times for each bracket/archwire combination. Frictional forces were measured in an Instron universal tensile machine at 3 mm/minute speed and a total displacement of 6 mm. Statistical analysis comprised ANOVA and Dunnett's multiple comparison post hoc test. RESULTS: Deflection-induced frictional (DIF) forces increased in the following order: Synergy, Damon, 8-shaped Ligature, Easy Clip, In-Ovation, Smart-Clip and conventional ligatures. The differences among groups were significant, with the exception of the 8-shaped ligature groups which was equal to the Damon and Easy Clip groups. CONCLUSIONS: Compared to conventional ligatures, all ligation systems tested reduced frictional forces. However, such reduction varied according to the ligation system employed.

Gilberto Vilanova, Queiroz; Rafael Yagüe, Ballester; João Batista, De Paiva; José, Rino Neto; Giselle Mara, Galon.

2012-08-01

183

Comparative study of frictional forces generated by NiTi archwire deformation in different orthodontic brackets: In vitro evaluation / Estudo comparativo da força de atrito produzida pela deformação de arco NiTi em diferentes braquetes ortodônticos: avaliação in vitro  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese OBJETIVO: o objetivo desse trabalho foi comparar as forças de atrito entre fios NiTi 0,014" (Aditek) com deformações horizontais de 4mm, e braquetes com diferentes sistemas de ligação dos arcos. MÉTODOS: foram testados 4 tipos de braquetes autoligáveis (Damon MX, Easy Clip, Smart Clip e In-Ovation), [...] um braquete triplo (Synergy) e um braquete gêmeo com amarrilho 8 (Tecnident). Como grupo controle, foi utilizado braquete gêmeo com ligadura elástica convencional (Morelli). Foram executadas 10 repetições em cada combinação arco/braquete. As forças de atrito foram medidas em máquina de tração universal Instron, com velocidade de 3mm/minuto e deslocamento total de 6mm. Para análise estatística, usou-se a ANOVA e o Teste de Comparações Múltiplas de Dunnett. RESULTADOS: as forças de atrito por deformação do fio se mostraram crescentes na seguinte ordem: Synergy, Damon, amarrilho 8, Easy Clip, In-Ovation, Smart-Clip e ligadura convencional. As diferenças entre todos os grupos foram estatisticamente significantes, com exceção do Amarrilho 8 em relação aos grupos Damon e Easy Clip. CONCLUSÃO: em relação à ligadura convencional, todos os sistemas de fechamento das canaletas testados são eficientes em reduzir a força de atrito, porém, tal redução varia significativamente de acordo com o sistema de fechamento da canaleta selecionado. Abstract in english INTRODUCTION: The purpose of this study was to compare the frictional forces between 0.014-in NiTi wires (Aditek) with 4 mm horizontal deflection and brackets with different archwire ligation systems. METHODS: Four types of self-ligating brackets (Damon MX, Easy Clip, Smart Clip and In-Ovation), a t [...] riple bracket (Synergy) and a twin bracket with 8-shaped ligature (Tecnident) were tested. Twin brackets with conventional elastomeric ligatures (Morelli) were used as control group. Tests were repeated 10 times for each bracket/archwire combination. Frictional forces were measured in an Instron universal tensile machine at 3 mm/minute speed and a total displacement of 6 mm. Statistical analysis comprised ANOVA and Dunnett's multiple comparison post hoc test. RESULTS: Deflection-induced frictional (DIF) forces increased in the following order: Synergy, Damon, 8-shaped Ligature, Easy Clip, In-Ovation, Smart-Clip and conventional ligatures. The differences among groups were significant, with the exception of the 8-shaped ligature groups which was equal to the Damon and Easy Clip groups. CONCLUSIONS: Compared to conventional ligatures, all ligation systems tested reduced frictional forces. However, such reduction varied according to the ligation system employed.

Gilberto Vilanova, Queiroz; Rafael Yagüe, Ballester; João Batista, De Paiva; José, Rino Neto; Giselle Mara, Galon.

184

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)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese 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.

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

185

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  

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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.

Walter Leal de Moura

2004-06-01

186

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)

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)

Yoshiyasu, Roseli Y.A

2001-07-01

187

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

LENUS (Irish Health Repository)

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.

Macauley, Donal

2012-12-01

188

Frictional Resistance of Three Types of Ceramic Brackets  

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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.

Claire L Williams

2014-01-01

189

Mapping chemical elements on the surface of orthodontic appliance by SEM-EDX  

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Background During orthodontic treatment, the various elements that constitute the fixed appliance undergo different processes. As a result of a change of the surface, elution/coverage of metals on the surface can be observed in the process of corrosion/passivation. Material/Methods Scanning electron microscopy with an energy-dispersive X-ray analytical system (SEM-EDX) was used to analyze the composition of stainless steel elements of orthodontic fixed appliances (before and after orthodontic treatment), to obtain the composition of the surface of the elements. The analyzed elements were: brackets (Victory Series APC PLUS 022, 3M Unitek, Monrovia, CA, USA); wires (0.017×0.025, 3M Unitek, Monrovia, CA, USA); and bands (37+, 3M Unitek, Monrovia, CA, USA). Results The results showed a decrease of chromium and iron contribution to the surface, with increase of oxygen content in used vs. new elements of the appliance. Conclusions Our results confirm the formation of oxides (passivation layer) on the surface of stainless steel as a result of the presence of the orthodontic appliance in patients’ oral cavities. PMID:24857929

Mikulewicz, Marcin; Wolowiec, Paulina; Michalak, Izabela; Chojnacka, Katarzyna; Czopor, Wojciech; Berniczei-Royko, Adam; Vegh, Andras; Gedrange, Thomas

2014-01-01

190

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

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Full Text Available SciELO Brazil | Language: English Abstract in portuguese 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.

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

191

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

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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

192

How and why of orthodontic bond failures: An in vivo study  

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Introduction: The bonding of orthodontic brackets and their failure rates by both direct and in-direct procedures are well-documented in orthodontic literature. Over the years different adhesive materials and various indirect bonding transfer procedures have been compared and evaluated for bond failure rates. The aim of our study is to highlight the use of a simple, inexpensive and ease of manipulation of a single thermo-plastic transfer tray and the use the of a single light cure adhesive to evaluate the bond failure rates in clinical situations. Materials and Methods: A total of 30 patients were randomly divided into two groups (Group A and Group B). A split-mouth study design was used, for, both the groups so that they were distributed equally with-out bias. After initial prophylaxis, both the procedures were done as per manufactures instructions. All patients were initially motivated and reviewed for bond failures rates for 6 months. Results: Bond failure rates were assessed for over-all direct and indirect procedures, anterior and posterior arches, and for individual tooth. Z-test was used for statistically analyzing, the normal distribution of the sample in a spilt mouth study. The results of the two groups were compared and P value was calculated using Z-proportion test to assess the significance of the bond failure. Conclusion: Over-all bond failure was more for direct bonding. Anterior bracket failure was more in-direct bonding than indirect procedure, which showed more posterior bracket failures. In individual tooth bond failure, mandibular incisor, and premolar brackets showed more failure, followed by maxillary premolars and canines.

Vijayakumar, R. K.; Jagadeep, Raju; Ahamed, Fayyaz; Kanna, Aprose; Suresh, K.

2014-01-01

193

Effects of brackets and ties on stiffness of an arch wire.  

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Beam theory was used to evaluate the stiffness of a simulated orthodontic model as affected by the type of bracket, interbracket distance, type of ligature tie, and size of segment. For a given deflection, the model generated greater force (increased stiffness) as the beam constant (N) increased. N increased as interbracket distance increased. Metal ties were as rigid or more rigid than o-rings. Four bracket segments were more rigid than two-bracket segments when tied with o-rings but not metal ligatures. Values of N of Lewis and narrow twin brackets with metal ties were similar and greater than the N of wide twin and medium single brackets. Wide twin brackets were more rigid than others with o-rings. PMID:3468796

Adams, D M; Powers, J M; Asgar, K

1987-02-01

194

Deformation of metal brackets: a comparative study.  

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The purpose of this study was to determine the effect of material and design on the force and stress required to permanently deform metal brackets. Fourteen types of metal brackets were categorized according to raw material composition, slot torque degree, and wing type. Five types of raw materials, three types of slot torque degree, and four types of wing design were tested using an archwire torque test developed by Flores. An analysis of variance (ANOVA) and t-test showed that all three categories had a significant effect on the force and stress needed to permanently deform metal brackets. Of the three, raw material had the greatest effect on the amount of force. Results showed that 17-4PH and 303S had higher yield strengths and regular twin brackets had higher resistance to deformation. Also, as slot torque degree increased, brackets deformed with less force. Result confirmed that brackets requiring the greatest stress to permanently deform were made of steel with the greatest hardness. PMID:7978523

Flores, D A; Choi, L K; Caruso, J M; Tomlinson, J L; Scott, G E; Jeiroudi, M T

1994-01-01

195

Evaluation of the orthodontic application of two new restorative systems.  

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Full Text Available AIM: As new adhesives, composite resins and bonding techniques were introduced, orthodontists adopted some of these innovations and added them to their armamentarium. The purpose of this study was to compare the shear bond strength (SBS of three adhesive systems used in dentistry; one with an organically modified matrix, Admira (Voco, Cuxhaven, Germany, another that contains the traditional Bis GMA matrix namely Transbond XT (3M Unitek, Monrovia, CA, and a nano-filled composite resin Grandio (Voco, Cuxhaven, Germany. MATERIALS AND METHODS: Sixty freshly extracted human molars were randomly divided into 3 groups; 20 teeth were bonded with Transbond XT, 20 teeth with Admira, and 20 teeth with Grandio. MAIN OUTCOME MEASURES: The analysis of variance was used to compare the SBS of the three groups. If significant differences were present, Tukey’s posterior tests for harmonic mean sample size were used to determine which of the means were significantly different from each other. Significance for all statistical tests was predetermined at p?0.05. RESULTS: The results of the Analysis of Variance (F-value = 0.545 of the SBS indicated that there was no significant (p=0.583 differences between the three groups tested. The mean SBS for Admira was 5.1±3.3 MPa, for Grandio 4.1±2.6 MPa and that for Transbond XT was 4.6±3.2 MPa. During debonding 3 of 20 brackets (15% in each of the Admira and Grandio groups failed without registering any force on the testing machine recording. None of the brackets bonded with Transbond XT had a similar failure mode. CONCLUSIONS: It was concluded that new materials that are being introduced in operative dentistry can potentially have orthodontic applications if the flow of these materials can be improved to better adhere to the bracket bases.

J. F. Laffoon

2004-01-01

196

Comparision of Shear Bond Strength of Stainless Steel and Ceramic Brackets at 24 Hours after Etching Enamel with Different Proportions of Acidulated Phosphate Fluoride  

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Aims and Objectives: To evaluate and compare the shear bond strength of stainless steel brackets and ceramic brackets at 24h after etching the enamel with acidulated phosphate fluoride gel (1.23% APF) at different proportions (40%,30%,20%) incorporated in conventional etchant (37% phosphoric acid). Materials and Methods: Eighty premolars (maxillary and mandibular first and second premolars) extracted for orthodontic purpose has been selected for the study and samples were divided into 4 groups containing 10 teeth each. Comprised of teeth etched Group 1 with 40% of APF gel etchant is Group 2 teeth etched with 30% of APF gel in Group 3 teeth etched with 20% of APF gel etchant and Group 4 teeth were etched with conventional etchant (37% phosphoric acid). Results: The experimental group of Acidulated Phosphate Fluoride (APF) at different proportion (40%, 30%, 20%) incorporated with etchant application for 40s on the enamel surface at 24h indicated that group 4 showed the higher bond strength of all other remaining groups and the groups 1, 2 and 3 showed satisfactory bond strength. The statistical evaluation also revealed that the bond strength of control group (37% phosphoric acid) was greater than those of experimental groups. Conclusion: The present study results shows that the ceramic brackets have higher bond strength than stainless steel brackets (material wise). PMID:25302260

Abinaya; Karthikeyan; Sarvanan; Vikram, Raj

2014-01-01

197

Automatic method of analysis of OCT images in the assessment of the tooth enamel surface after orthodontic treatment with fixed braces  

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Introduction Fixed orthodontic appliances, despite years of research and development, still raise a lot of controversy because of its potentially destructive influence on enamel. Therefore, it is necessary to quantitatively assess the condition and therein the thickness of tooth enamel in order to select the appropriate orthodontic bonding and debonding methodology as well as to assess the quality of enamel after treatment and clean-up procedure in order to choose the most advantageous course of treatment. One of the assessment methods is computed tomography where the measurement of enamel thickness and the 3D reconstruction of image sequences can be performed fully automatically. Material and method OCT images of 180 teeth were obtained from the Topcon 3D OCT-2000 camera. The images were obtained in vitro by performing sequentially 7 stages of treatment on all the teeth: before any interference into enamel, polishing with orthodontic paste, etching and application of a bonding system, orthodontic bracket bonding, orthodontic bracket removal, cleaning off adhesive residue. A dedicated method for the analysis and processing of images involving median filtering, mathematical morphology, binarization, polynomial approximation and the active contour method has been proposed. Results The obtained results enable automatic measurement of tooth enamel thickness in 5 seconds using the Core i5 CPU M460 @ 2.5GHz 4GB RAM. For one patient, the proposed method of analysis confirms enamel thickness loss of 80 ?m (from 730?±?165 ?m to 650?±?129 ?m) after polishing with paste, enamel thickness loss of 435 ?m (from 730?±?165 ?m to 295?±?55 ?m) after etching and bonding resin application, growth of a layer having a thickness of 265 ?m (from 295?±?55 ?m to 560?±?98 ?m after etching) which is the adhesive system. After removing an orthodontic bracket, the adhesive residue was 105 ?m and after cleaning it off, the enamel thickness was 605 ?m. The enamel thickness before and after the whole treatment decreased by about 125 ?m. Conclusions This paper presents an automatic quantitative method for the assessment of tooth enamel thickness. This method has proven to be an effective diagnostic tool that allows evaluation of the surface and cross section of tooth enamel after orthodontic treatment with fixed thin-arched braces and proper selection of the methodology and course of treatment. PMID:24755213

2014-01-01

198

Surface characterization of retrieved NiTi orthodontic archwires.  

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The structure and morphological condition of retrieved NiTi orthodontic archwires was evaluated and any possible alterations in the surface composition of the alloy following 1-6 months in vivo were characterized. NiTi wires (GAC, German Orthodontics, ORMCO) of various cross-sections were collected through a retrieval protocol and were subjected to multi-technique characterization. Optical microscopy revealed islands of amorphous precipitants and accumulated microcrystalline particles. Micro MIR-FTIR investigation of the retrieved samples demonstrated the presence of a proteinaceous biofilm, the organic constituents of which were mainly amide, alcohol, and carbonate. Scanning electron microscope and X-ray microanalysis showed that the elemental species precipitated on the material surface were Na, K, Cl, Ca, and P, forming NaCl, KCl, and Ca-P precipitates. Increased intra-oral exposure was consistently associated with the presence of a mature film, while evidence of alloy delamination, pitting, and crevice corrosion, as well as a notable reduction in the alloy grain size was observed. Intra-oral exposure of NiTi wires alters the topography and structure of the alloy surface through surface attack in the form of pitting or crevice corrosion or formation of integuments. Further in vivo research is required to resolve the implications of the described ageing pattern in the corrosion resistance of the alloy, the potential for nickel leaching, as well as bracket-archwire friction variants. PMID:10920564

Eliades, T; Eliades, G; Athanasiou, A E; Bradley, T G

2000-06-01

199

In vivo bracket bond strength using two adhesive systems applied under wet and dry conditions.  

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The purpose of this study was to investigate, in vivo, the bond strength of two adhesive materials: a moisture insensitive primer (MIP)* and a one step self etching primer (SEP)*, both used with Transbond XT* on dry and wet enamel and an adhesion time of 10-15 minutes. First or second upper and/or lower bicuspids (n = 124), to be extracted for orthodontic reasons, were used. A comparison of the materials' behavior was conducted under four different situations: 1) MIP on enamel etched and dry; 2) MIP on a surface etched and wetted with patient's saliva; 3) SEP on a dry field, 4) SEP on a saliva-wet enamel. For statistical analysis, Dunn-Sidak's multiple comparison test was applied with a probability of less than 0.05 (before correction). Stainless steel brackets with mesh-backed pads were bonded to the teeth. Bond strength was tested with modified orthodontic pliers on which a strain-gage was fixed to measure handle deformation while debonding. Moisture insensitive primer tested on wet enamel showed the highest mean bond strength outcomes (8.98 MPa) compared to one step etching primer (5.81 MPa). Statistical difference between these groups was significant (p = 0.000). Standard deviation was lower for the one-step technique, under dry and wet conditions. Since the media bond strength of SEP proved sufficient for clinical purposes and its behavior tended to be more homogeneous, this was considered the best choice. PMID:17121197

Ciola, Elida N; Picco, Alicia M; Sois, Ana M; Lucena, Mercedes H; Alonso, Verónica; Valvo, Maela; García, Luis; Geazzi, Ariel

2006-01-01

200

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

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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.

Zufall, Scott William

 
 
 
 
201

Er:YAG Laser for Brackets Bonding: A SEM Study after Debonding  

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Background. The introduction of Er:YAG laser in dentistry for ablation of hard tissues advocated an alternative method of enamel etching for orthodontics purpose. Materials and Methods. 55 extracted human third molars were inserted in acrylic resin blocks and divided into five groups of 11 teeth. Group 1 was treated with 37% orthophosphoric acid for 30 seconds. Group 2 was treated with laser irradiation (Er:YAG Fidelius III, Fotona, Slovenia) at 80?mJ and 4?Hz. Group 3 underwent laser treatment (80?mJ, 4?Hz), followed by 37% orthophosphoric acid for 30 seconds. The teeth in Group 4 were treated with laser at 40?mJ and 10?Hz. The teeth in Group 5 were treated with laser (40?mJ, 10?Hz), followed by 37% orthophosphoric acid for 30 seconds. The adhesive remnant index was determined after debonding. Results. Kruskas-Wallis test showed that location parameters (median and mean) are significantly different between Groups 2 and 4 when compared with control group; on the contrary no significant difference was detected between Groups 3 and 5 with the controls. Conclusion. The use of Er:YAG laser alone, as in Groups 2 and 4, showed no significant advantages over phosphoric acid in the bonding procedure for orthodontics brackets. PMID:25405238

Ierardo, G.; Di Carlo, G.; Petrillo, F.; Luzzi, V.; Vozza, I.; Migliau, G.; Kornblit, R.; Rocca, J. P.; Polimeni, A.

2014-01-01

202

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

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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.

Ulises Velazquez-Enriquez

2012-10-01

203

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

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english 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.

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

2012-10-01

204

Nickel hypersensitivity reaction before, during, and after orthodontic therapy.  

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Nickel is a strong biological sensitizer and consequently may induce a delayed hypersensitivity reaction (type IV immune response). Because nickel is a component of the majority of the orthodontic alloys, the objectives of this cross-sectional study were to determine the prevalence of nickel hypersensitivity reaction before, during, and after orthodontic therapy with conventional stainless steel brackets and wires; to evidence the induction of this reaction by the orthodontic appliances; and to characterize the nickel hypersensitive persons. Nickel patch tests and a questionnaire were used to evaluate the hypersensitivity to this metal. The total sample consisted of 170 patients, 105 females and 65 males, from the orthodontic department at Bauru Dental School, University of São Paulo. They were divided into three groups as follows: A (n = 60), patients before the beginning of orthodontic therapy; B (n = 66), patients currently undergoing orthodontic treatment, and C (n = 44), patients who had undergone orthodontic treatment previously. The chi-square test (chi2) showed an allergic reaction in 28.3% of the total sample with 23% female and 5.3% male. This indicated a gender difference (chi2 = 10.75, p history to metals (chi2 = 34.88, p stainless steel appliances does not initiate or aggravate a nickel hypersensitivity reaction. PMID:9637569

Janson, G R; Dainesi, E A; Consolaro, A; Woodside, D G; de Freitas, M R

1998-06-01

205

A comparative assessment of forces and moments generated by lingual and conventional brackets.  

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The aim of this study was to assess the effect of bracket type on the labiopalatal forces and moments generated in the sagittal plane. Incognito™ lingual brackets (3M Unitek), STb™ lingual brackets (Light Lingual System; ORMCO), and conventional 0.018 inch slot brackets (Gemini; 3M Unitek) were bonded on three identical maxillary acrylic resin models, with a palatally displaced right lateral incisor. The transfer trays for the indirect bonding of the lingual brackets were constructed in certified laboratories. Each model was mounted on the orthodontic measurement and simulation system and ten 0.013 inch CuNiTi wires were used for each bracket type. The wire was ligated with elastomerics and each measurement was repeated once after re-ligation. The labiopalatal forces and the moments in the sagittal plane were recorded on the right lateral incisor. One-way analysis of variance and post hoc Scheffe pairwise comparisons were used to assess the effect on bracket type on the generated forces and moments. The magnitude of forces ranged from 1.62, 1.27, and 1.81 N for the STb, conventional, and Incognito brackets, respectively; the corresponding moments were 2.01, 1.45, and 2.19 N mm, respectively. Bracket type was a significant predictor of the generated forces (P < 0.001) and moments (P < 0.001). The produced forces were different among all three bracket types, whereas the generated moments differed between conventional and lingual brackets but not between lingual brackets. PMID:21464153

Sifakakis, Iosif; Pandis, Nikolaos; Makou, Margarita; Katsaros, Christos; Eliades, Theodore; Bourauel, Christoph

2013-02-01

206

Impact of brackets on smile esthetics: laypersons and orthodontists perception  

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Full Text Available 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 elastic 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.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 ligaduras 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.

Seandra Cordeiro de Oliveira

2012-10-01

207

Impact of brackets on smile esthetics: laypersons and orthodontists perception  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese 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.

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

208

Should silane coupling agents be used when bonding brackets to composite restorations? An in vitro study.  

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The purpose of this in vitro study was to determine a safe and efficient method for bonding brackets to resin composite (RC), permitting the brackets to tolerate shear forces and allowing removal without causing surface damage to the aesthetic restoration. The shear bond strength (SBS) of 60 brackets bonded to silanated and non-silanated RC surfaces were compared. A Bis-GMA containing orthodontic adhesive system was used to bond stainless steel upper lateral incisor brackets to 60 composite discs, half of which had surface treatment with a silane coupling agent. SBS testing was performed with an Instron universal testing machine. After debond, the bracket base and corresponding RC discs were examined under a stereomicroscope and analyzed using the Adhesive Remnant Index (ARI). Non-parametric tests (Mann-Whitney U) indicated significant differences between the two groups (P adhesive interface in both groups. There would appear to be no advantage in using a silane agent when bonding metal orthodontic brackets to filled RCs. PMID:19193708

Eslamian, Ladan; Ghassemi, Amir; Amini, Fariborz; Jafari, Alireza; Afrand, Mona

2009-06-01

209

Laser Application in Prevention of Demineralization in Orthodontic Treatment  

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Full Text Available One common negative side effect of orthodontic treatment with fixed appliances is the development of incipient caries lesions around brackets, particularly in patients with poor oral hygiene. Different methods have been used to prevent demineralization such as fluoride therapy and application of sealant to prevent caries. The recent effort to improve the resistance against the demineralization is by the application of different types of lasers. The purpose of this review article is discussing the effects of laser in prevention of demineralizationin orthodontic patients.

Hooman Sadr Haghighi

2013-06-01

210

A comparative assessment of torque generated by lingual and conventional brackets.  

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The aim of this study was to assess the effect of bracket type on the labiopalatal moments generated by lingual and conventional brackets. Incognito™ lingual brackets (3M Unitek), STb™ lingual brackets (Light Lingual System; ORMCO), In-Ovation L lingual brackets (DENTSPLY GAC), and conventional 0.018 inch slot brackets (Gemini; 3M Unitek) were bonded on identical maxillary acrylic resin models with levelled and aligned teeth. Each model was mounted on the orthodontic measurement and simulation system and 10 0.0175 × 0.0175 TMA wires were used for each bracket type. The wire was ligated with elastomerics into the Incognito, STb, and conventional brackets and each measurement was repeated once after religation. A 15 degrees buccal root torque (+15 degrees) and then a 15 degrees palatal root torque (-15 degrees) were gradually applied to the right central incisor bracket. After each activation, the bracket returned to its initial position and the moments in the sagittal plane were recorded during these rotations of the bracket. One-way analysis of variance with post hoc multiple comparisons (Tukey test at 0.05 error rate) was conducted to assess the effect on bracket type on the generated moments. The magnitude of maximum moment at +15 degrees ranged 8.8, 8.2, 7.1, and 5.8 Nmm for the Incognito, STb, conventional Gemini, and the In-Ovation L brackets, respectively; similar values were recorded at -15 degrees: 8.6, 8.1, 7.0, and 5.7 Nmm, respectively. The recorded differences of maximum moments were statistically significant, except between the Incognito and STb brackets. Additionally, the torque angles were evaluated at which the crown torque fell well below the minimum levels of 5.0 Nmm, as well as the moment/torque ratio at the last part of the activation/deactivation curve, between 10 and 15 degrees. The lowest torque expression was observed at the self-ligating lingual brackets, followed by the conventional brackets. The Incognito and STb lingual brackets generated the highest moments. PMID:22573909

Sifakakis, Iosif; Pandis, Nikolaos; Makou, Margarita; Eliades, Theodore; Katsaros, Christos; Bourauel, Christoph

2013-06-01

211

Why Orthodontic Treatment?  

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Why you should get orthodontic treatment The goal of orthodontic treatment is a beautiful smile and a good bite—meaning straight teeth that mesh well ... clenching of teeth Inability to comfortably close lips Orthodontics has come a long way A variety of ...

212

Bracketing effects on risk tolerance  

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Full Text Available Research has shown that risk tolerance increases when multiple decisions and associated outcomes are presented together in a broader ``bracket'' rather than one at a time. The present studies disentangle the influence of problem bracketing (presenting multiple investment options together from that of outcome bracketing (presenting the aggregated outcomes of multiple decisions, factors which have been deliberately confounded in previous research. In the standard version of the bracketing task, in which participants decide how much of an initial endowment to invest into each in a series of repeated, identical gambles, we find a problem bracketing effect but not an outcome bracketing effect. However, this pattern of results does not generalize to the cases of non-identical gambles nor discrete choice, where we fail to find the standard bracketing effect.

Ester Moher

2010-08-01

213

Effect of Activation Mode on Shear Bond Strength of Metallic Brackets  

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Full Text Available SciELO Brazil | Language: English Abstract in portuguese 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

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

2013-09-01

214

In-office bacteria test for a microbial monitoring during the conventional and self-ligating orthodontic treatment  

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Full Text Available Abstract This study investigated the microbial level of Streptococcus mutans and Lactobacillus spp. during an orthodontic treatment, and compare the data with untreated control subjects. Sixty young adult subjects were selected (average 20.5, DS 1.62, among which 40 underwent an orthodontic treatment (20 were treated with self-ligating brackets and 20 with conventional brackets and 20 were controls. Plaque Index, salivary flow and buffering capacity of saliva were assessed before the beginning of the orthodontic treatment. Then the microbial counts were obtained by using an in-office bacteria test. The plaque index (PI increased over time in each group as well as salivary flow, mostly in subjects treated with self-ligating brackets, suggesting a difference between conventional and self-ligating brackets. S.mutans showed a different trend of colonization in the two treated groups, as for subjects treated with conventional brackets it showed the greater value at the early stage of treatment (T1, followed by a decrease at T2. Lactobacillus spp. showed significant increase over time in the two treated groups, respect to the control group. Linear regression analysis showed no significant predictor for the microbial count at T2. The assortment of the various species of bacteria change over time during the orthodontic treatment, and seems to show different trends, depending on the type of orthodontic device. Consequently a periodical microbial monitoring using in-office bacteria tests, seems indicated.

Mummolo Stefano

2013-02-01

215

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

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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.

Ehmer Ulrike

2007-02-01

216

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

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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. PMID:17286873

Hohoff, Ariane; Joos, Ulrich; Meyer, Ulrich; Ehmer, Ulrike; Stamm, Thomas

2007-01-01

217

Halogen light versus LED for bracket bonding: shear bond strength  

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Full Text Available 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.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: um 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.

Paulo Eduardo Guedes Carvalho

2013-02-01

218

[Evaluation of the risk of overheating and displacement of orthodontic devices in magnetic resonance imaging].  

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The use of magnetic resonance imaging (MRI) in the exploration of the orofacial region of patients who have orthodontic appliances can be disturbed by artifacts, with a theoretical risk of displacement and overheating of the different materials used in odontology. The purpose of this study was to evaluate the thermal effects and the risk of displacement induced by MRI on certain metallic devices used in orthodontics. The results show a very moderate increase in temperature of the materials during MRI exposure, less than 1 degrees C, in particular in the metal wire linking the brackets. The maximal forces observed were on the order of 0.27 N. The risk of detachment and displacement seems to be nonexistent at 1.5 Tesla when the usual recommendations are respected. Temporary removal of the wire and verification of the adhesive is recommended. However, priority should be given to nonmagnetic or slightly magnetic material to limit artifacts as much as possible when exploring the head region. PMID:17372554

Yassi, K; Ziane, F; Bardinet, E; Moinard, M; Veyret, B; Chateil, J F

2007-02-01

219

Shear bond strength of new and recycled brackets to enamel  

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Full Text Available SciELO Brazil | Language: English Abstract in portuguese 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

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

220

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  

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Full Text Available SciELO Chile | Language: English Abstract in spanish 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.

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

 
 
 
 
221

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)

Full Text Available SciELO Chile | Language: English Abstract in spanish 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.

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

2014-09-01

222

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

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english 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.

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

223

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

Directory of Open Access Journals (Sweden)

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.

Luciana Borges Retamoso

2010-02-01

224

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

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english 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.

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

2010-02-01

225

Relationship between self-concept and satisfaction with tooth alignment and demand for orthodontic treatment and professionally determined orthodontic needs  

Digital Repository Infrastructure Vision for European Research (DRIVER)

AbstractIntroduction: Recognition of psychological factors plays an important role in determination of orthodontic treatment needs as well as achieving a successful treatment. The aim of this study was to investigate the relationship between self-concept, dentofacial body image, subjective orthodontic treatment needs and professionally determined needs for orthodontic treatment among a group of university students.Materials and Methods: In this cross-sectional study, 164 students of Isfahan F...

Amirreza Amnaie; Mahmood Nasiri; Mohsen Adib; Amin Shirvani

2012-01-01

226

[Corrosion and calculus. How can the wire/bracket slide mechanics be improved?].  

Science.gov (United States)

Sliding mechanics are widely used in fixed orthodontic devices. Parasitic phenomena that block or slow the movement have, until now, been relatively neglected. The friction that appears at the interface of the wire/bracket/ligature opposes the free sliding action, necessary to allow the motor forces to displace the dental units that are guided on an appropriately shaped metal arch. There are three main causes that make unpredictable the control of orthodontic forces. The first one is the involuntary irregularities introduced onto the arches during their construction. The two others consist in factors blocking the sliding action. They can be unknown or misunderstood: the superficial corrosion of wires and brackets which affect the polished surface, and the appearance of adherent concretions due to hard and adherent tartar. This paper will discuss their involvement and describe the ways to improve the sliding effects. PMID:11987534

Loreille, Jean-Paul

2002-03-01

227

Face Adaptation in Orthodontics  

Directory of Open Access Journals (Sweden)

Full Text Available Bilateral Controversy in orthodontic science is widely present in different patterns; one of the most common is the debate between early versus late orthodontic treatment. This paper is going to demonstrate two clinical cases of class III malocclusion which are treated orthodontically, one in early mixed dentition and the other in permanent dentition. The face is highly capable to adapt to the changes achieved by orthodontics provided the earlier treatment begins, the more the face adapts to our standards; the later treatment begins, the more our standards have to adapt to the face.

Maen Mahfouz

2014-07-01

228

Improvement of orthodontic friction by coating archwire with carbon nitride film  

Energy Technology Data Exchange (ETDEWEB)

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.

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

229

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.

230

Improvement of orthodontic friction by coating archwire with carbon nitride film  

Science.gov (United States)

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 2 carbon dominated structures, and diversiform bonds (N sbnd C, N tbnd 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 2C 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.

Wei, Songbo; Shao, Tianmin; Ding, Peng

2011-10-01

231

Effect of a self-etching primer on shear bond strength of adhesive precoated brackets in vivo.  

Science.gov (United States)

The aim of this study was to evaluate the influence of a self-etching primer (SEP) (Transbond Plus SEP, 3M Unitek, Monrovia, Calif) on shear bond strength of adhesive uncoated and precoated Victory brackets (3M Unitek). The sample group consisted of 23 patients, with four premolars each, equally divided in four different groups. Brackets were bonded in vivo by the same operator using a split-mouth random technique: group 1, 37% phosphoric acid + primer + composite + conventional Victory bracket; group 2, 37% phosphoric acid + primer + precoated Victory bracket; group 3, SEP + composite + conventional bracket; group 4, SEP + precoated bracket. After 30 days, premolars were extracted for orthodontic reasons and a Universal Instron Machine was used to apply an occlusal shear force directly to the enamel-bracket interface at a speed of 0.5 mm/min. The groups were compared using two-way analysis of variance. Mean results and standard deviation for the groups were: group 1 = 11.60 +/- 2.65 Mpa, group 2 = 9.79 +/- 2.71 Mpa, group 3 = 10.75 +/- 2.67 Mpa, and group 4 = 10.31+/- 2.70 Mpa. No difference was observed between the conventional etching and primer or SEP (P = .948). However, significant differences in bond strength were present between the uncoated and precoated brackets (P = .032). Considering the values required to withstand normal orthodontic forces (8-9 Mpa), it could be concluded that the SEP combined with adhesive precoated brackets showed adequate shear bond strength and may be suitable for clinical use. PMID:16448282

Cal-Neto, Julio P; Miguel, José Augusto M; Zanella, Eduardo

2006-01-01

232

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

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english 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 de [...] ntal 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.

Michela M. D. S., Sostena; Renata A., Nogueira; Carlos R., Grandini; João Carlos Silos, Moraes.

2009-12-01

233

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

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english 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.

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

2013-12-01

234

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

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english 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.

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

235

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

DEFF Research Database (Denmark)

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 treatment with fixed appliances were enrolled and randomly allocated to a randomized controlled trial with two parallel groups. The intervention group was instructed to drink one glass of milk (~ 200 ml) supplemented with fluoride (5 ppm) once daily and the subjects of the control group to drink the same amount of milk without fluoride. The intervention period was 12 weeks and the end-point was mineral gain or loss in enamel, assessed by QLF on two selected sites from each individual. The attrition rate was 12.5% and 112 sites were included in the final evaluation. Results. There was no statistically significant difference between the groups concerning fluorescence (¿F) values and lesion area (A mm(2)) at baseline.After 12 weeks, a significant decrease (p <0.05) in ¿F was registered in the fluoridated milk group and a significant increase in the non-fluoride control group (p <0.05). The mean reduction in the test group was somewhat lower (14%) than the increase in the control group (18%), but individual variations were evident. Only minor alterations of lesion area were recorded over the 12-week period and no statistically significant differences compared with baseline were found in any of the groups. Conclusion. Daily intake of fluoridated milk may aid remineralization of white spot lesions adjacent to fixed orthodontic appliances.

Sköld-Larsson, Kerstin; Sollenius, Ola

2012-01-01

236

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  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese 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. Abstract in english 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 1 [...] 2 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.

Patrícia Helou Ramos, Andrade; Rogério Vieira, Reges; Marcos Augusto, Lenza.

2012-08-01

237

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

Energy Technology Data Exchange (ETDEWEB)

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.

Barrett, R.D.

1990-05-01

238

Orthodontic wire: a continuing evolution.  

Science.gov (United States)

Wires have substantial structural presence in active and retentive orthodontic therapy. Wires, and auxiliaries fabricated from wire, may deliver force to produce dental displacements, they may attempt to prevent unwanted displacements, or they may simply carry force from one location to another within the dentofacial complex. Wires may have relatively simple or rather convoluted geometries. The most prominent wire in clinical orthodontic treatment is the "arch wire." Marketed in just two, symmetrical, cross-sectional shapes, its sizes are numerous, and arch wires are manufactured of a variety of metallic alloys and compositions. The primary objective of this article is to trace the history of arch wires over the past century, considering the evolution from the stiff arch bow to the wire exhibiting Hookean material behavior, from the precious metal to the stainless steel to the titanium alloys, and into the era of the "superelastic" wire and a thermomechanical behavior decidedly more complex than its predecessors. Timely, relevant questions that are addressed herein pertain to the current "state-of-the-art" of orthodontic wires, the extent to which the mechanics of the "old" and new wires are understood, and the anticipated arch wire advancements in the near future as a new millennium approaches. PMID:9573877

Nikolai, R J

1997-09-01

239

Fricção em braquetes gerada por fios de aço inoxidável, superelásticos com IonGuard e sem IonGuard Friction force on brackets generated by stainless steel wire and superelastic wires with and without IonGuard  

Directory of Open Access Journals (Sweden)

Full Text Available OBJETIVO: o objetivo deste estudo foi verificar a fricção no braquete (Roth, Composite, 10.17.005, 3,2mm, largura 0,022" x 0,030", Torque -2° e angulação +13°, Morelli®, Brasil, utilizando fios ortodônticos retangulares de 0,019" x 0,025" de aço inoxidável (Morelli®, Brasil e de níquel-titânio superelásticos Bioforce com IonGuard e sem IonGuard (Bioforce, GAC®, EUA. MÉTODOS: foram utilizados 24 conjuntos braquetes/segmento de fio, divididos em 3 grupos de acordo com o fio. Cada conjunto braquete/segmento de fio foi testado 3 vezes e obtida uma média. Os ensaios foram realizados em máquina universal de ensaios EMIC DL2000®. Os dados foram submetidos à Análise de Variância com significância de 95%. RESULTADOS: o fio retangular Bioforce com IonGuard apresentou fricção significativamente menor que o Bioforce sem IonGuard, porém sem diferença do fio de aço inoxidável. Entretanto, o coeficiente de variação dos fios Bioforce com e sem IonGuard foi menor que o do fio de aço inoxidável. CONCLUSÃO: os fios retangulares de 0,019" x 0,025" Bioforce com IonGuard apresentam menor fricção que o fio Bioforce sem IonGuard, sem diferença para o fio de aço inoxidável.OBJECTIVE: The aim of this study was to evaluate the friction forces on brackets (Roth, Composite, 10.17.005, 3.2 mm, width 0.022" x 0.030 ", Torque -2° and angulation +13°, Morelli®, Brazil, with stainless steel orthodontic rectangular wire (Morelli®, Brazil and nickel titanium superelastic Bioforce wires with and without IonGuard (Bioforce, GAC®, USA. MATERIAL AND METHODS: Twenty-four brackets/wire segment combinations were used, distributed into three groups according to the orthodontic wire. Each bracket/wire segment combination was tested three times. The tests were performed in a universal testing machine Emic DL2000®. The data was submitted to ANOVA one way followed by Tukey's post hoc test (p<0.05. RESULTS: The rectangular orthodontic Bioforce wire with IonGuard presented significantly lower resistance to sliding than Bioforce without IonGuard. There was no statistical difference among the other groups. However, the coefficient of variation of Bioforce with and without IonGuard was lower than that of the stainless steel wire. CONCLUSION: The rectangular orthodontic Bioforce wire with IonGuard presented lower resistance to sliding than Bioforce without IonGuard, with no difference to the stainless steel wire.

Luiz Carlos Campos Braga

2011-08-01

240

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  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese 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 (p Abstract in english OBJECTIVE: 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 res [...] in 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

Michele Balestrin, Imakami; Karyna Martins, Valle-Corotti; Paulo Eduardo Guedes, Carvalho; Ana Carla Raphaelli Nahás, Scocate.

 
 
 
 
241

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  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese 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 (p Abstract in english OBJECTIVE: 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 res [...] in 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

Michele Balestrin, Imakami; Karyna Martins, Valle-Corotti; Paulo Eduardo Guedes, Carvalho; Ana Carla Raphaelli Nahás, Scocate.

2011-06-01

242

Comparison between two methods for resin removing after bracket debonding  

Directory of Open Access Journals (Sweden)

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.

Rodrigo De Marchi

2012-12-01

243

Degradation of orthodontic wires under simulated cariogenic and erosive conditions  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english 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.

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

2014-08-04

244

Torque expression of 0.018 and 0.022 inch conventional brackets.  

Science.gov (United States)

The aim of this study was to assess the effect of the moments generated with low- and high-torque brackets. Four different bracket prescription-slot combinations of the same bracket type (Mini Diamond® Twin) were evaluated: high-torque 0.018 and 0.022 inch and low-torque 0.018 and 0.022 inch. These brackets were bonded on identical maxillary acrylic resin models with levelled and aligned teeth and each model was mounted on the orthodontic measurement and simulation system (OMSS). Ten specimens of 0.017 × 0.025 inch and ten 0.019 × 0.025 inch stainless steel archwires (ORMCO) were evaluated in the low- and high-torque 0.018 inch and 0.022 inch brackets, respectively. The wires were ligated with elastomerics into the brackets and each measurement was repeated once after religation. Two-way analysis of variance and t-test were conducted to compare the generated moments between wires at low- and high-torque brackets separately. The maximum moment generated by the 0.017 × 0.025 inch stainless steel archwire in the 0.018 inch brackets at +15 degrees ranged from 14.33 and 12.95 Nmm for the high- and low-torque brackets, respectively. The measured torque in the 0.022 inch brackets with the 0.019 × 0.025 inch stainless steel archwire was 9.32 and 6.48 Nmm, respectively. The recorded differences of maximum moments between the high- and low-torque series were statistically significant. High-torque brackets produced higher moments compared with low-torque brackets. Additionally, in both high- and low-torque configurations, the thicker 0.019 × 0.025 inch steel archwire in the 0.022 inch slot system generated lower moments in comparison with the 0.017 × 0.025 inch steel archwire in the 0.018 inch slot system. PMID:22828075

Sifakakis, Iosif; Pandis, Nikolaos; Makou, Margarita; Eliades, Theodore; Katsaros, Christos; Bourauel, Christoph

2013-10-01

245

Design Modification for Failed Grill Bracket using Finite Element Analysis  

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Full Text Available Grill is a part placed on vehicle located in front of the Engine cooling module by means of bracket. The purpose of the Grill is to protect the cooling module from front impact and at the same time provide appropriate aesthetic value to the vehicle. This report presents the failure analysis of grill bracket of Engine cooling module of a Truck using Finite Element Analysis. The Grill bracket has failed in the field before warranty period so it has to be replaced with new one. Replacing old bracket means economic loss to the company. The Failure of this Grill bracket is analysed using Finite Element Analysis. 3 D models were created using Pro –E CAD softwares and Finite element analysis was done using Medina and Permas softwares. After doing Finite Element Analysis it was observed that high stresses were coming at failure location on the Grill bracket. The high stresses were mainly observed due to accelerations loads. Several proposals for alternate designs were created considering the packaging data, availability of the standard materials and manufacturing feasibility. These alternate designs were again checked by finite element analysis. The most optimized design was finalized through this process. The finalized design showed 60% lower stress values at failure location compared to current design. New proposed design was found to pass the given warranty period (100000 miles. Thus Finite element analysis proved to be very suitable tool for the situation where quick solution is expected.

K. S. Kulkarni

2013-03-01

246

Laser diagnostics in orthodontics  

Science.gov (United States)

The results of statistical analysis of Doppler spectra of intensity fluctuations of light, scattered from mucose membrane of oral cavity of healthy volunteers and patients, abused by the orthodontic diseases, are presented. Analysis of Doppler spectra, obtained from tooth pulp of patients, is carried out. New approach to monitoring of blood microcirculation in orthodontics is suggested. Influence of own noise of measuring system on formation of the speckle-interferometric signal is studied.

Ryzhkova, Anastasia V.; Lebedeva, Nina G.; Sedykh, Alexey V.; Ulyanov, Sergey S.; Lepilin, Alexander V.; Kharish, Natalia A.

2003-10-01

247

Involvement of TSP1 and MMP9/NGAL in Angiogenesis during Orthodontic Periodontal Remodeling  

Science.gov (United States)

In the present study the aim was to measure the levels of Thrombospondin-1 (TSP1) and Lipocalin-2/matrix metalloproteinase 9 (MMP9/NGAL) complex in gingival crevicular fluid (GCF) at different time points of orthodontic treatment, to determine the relationship between these values and those of total-matrix metalloproteinase 9 (MMP9) and theirs implication in angiogenesis balance, in the situation of a good control of the bacterial plaque, emphasizing the role of TSP1 and MMP9/NGAL complex. GCF samples were collected from 16 young orthodontic patients requiring upper canine distalization (test tooth) with first premolar extraction. The contralateral canine (control tooth) was free from orthodontic force. For the orthodontic appliance, brackets Roth 0.018?inch with 0.012?inch NiTi archwire and a laceback were used. TSP1, MMP9/NGAL, and MMP9 increased from 1 hour before activation of orthodontic appliance to a maximum at 8 hours for MMP9 and 72 hours for MMP9/NGAL and TSP1. The results show a change in time of TSP1, MMP9/NGAL, and MMP9 levels in GCF of patients with this method of orthodontic treatment. The powerful correlation of MMP9/NGAL with TSP1 suggests their stronger involvement in angiogenesis processes in PDL during orthodontic periodontal remodeling, in the situation of a healthy periodontium and a good control of the bacterial plaque. PMID:24967433

Surlin, Petra; Silosi, Isabela; Rauten, Anne Marie; Cojocaru, Manole; Foia, Lili

2014-01-01

248

Halogen light versus LED for bracket bonding: shear bond strength  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese 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.

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

249

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

Science.gov (United States)

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

Melsen, Birte

2011-06-01

250

Beta titanium: a new orthodontic alloy.  

Science.gov (United States)

Historically, few alloys have been used in the fabrication of orthodontic appliances. This article reviews the gold-based, stainless steel, chrome-cobalt-nickel, and nitinol alloys, as well as beta titanium, a new material for orthodontics. Mechanical properties and manipulative characteristics are summarized to develop a basis for the selection of the proper alloy for a given clinical situation. The beta titanium wire has a unique balance of low stiffness, high springback, formability, and weldability which indicates its use in a wide range of clinical applications. A number of such applications are described. PMID:6928342

Burstone, C J; Goldberg, A J

1980-02-01

251

On Derivation of Goldman Bracket  

CERN Document Server

Non abelian Gauge field theory on space-time, modeled as a noncompact 3-manifold $\\Sigma\\times\\mathbb{R}$, with $\\Sigma$ being a compact Riemann surface and time taking values in $\\mathbb{R}$, has been considered. The Atiyah-Bott brackets between the gauge fields have been computed in this infinite dimensional setting. Traces of monodromies of the gauge connections around free homotopy classes of closed loops on the underlying Riemann surface and the Poisson brackets between them are computed using the formalism originated from hamiltonian methods of Soliton theory. Finally, the brackets for real Lie groups $GL(n,\\mathbb{R})$, $SL(n,\\mathbb{R})$, U(n), SU(n) and $Sp(2n,\\mathbb{R})$ are explicitly worked out.

Chowdhury, S Hasibul Hassan

2013-01-01

252

Eighteen-month bracket survival rate: conventional versus self-etch adhesive.  

Science.gov (United States)

The aim of this study was to evaluate, over an 18-month period, the clinical performance of a self-etch adhesive [Transbond Plus Self Etching Primer (SEP), 3M Unitek] compared with a conventional adhesive that employs the etch-and-rinse approach (Transbond XT, 3M Unitek). One operator, using the straight-wire technique, bonded 567 metallic brackets to the teeth of 30 patients (age range 12-18 years) in a way that patients acted as self-control. The brackets were bonded following the manufacturers' instructions except for the fact that the self-etch system was brushed for a longer time than recommended (10-15 seconds) since previous investigations have reported that prolonged application times can improve the bonding efficacy of self-etch systems to enamel. The failure modes were visually classified into: adhesive-enamel, adhesive-bracket, and cohesive failure. The survival rates of the brackets were estimated by Kaplan-Meier and log-rank test (P 0.05). Most of the failures were cohesive and at the adhesive-enamel interface. There was no difference in the fracture debonding mode. These findings indicate that Transbond Plus SEP can be safely used for orthodontic brackets since the survival rates are similar to the conventional Transbond XT. PMID:17989121

Reis, Alessandra; dos Santos, José Elui; Loguercio, Alessandro Dourado; de Oliveira Bauer, José Roberto

2008-02-01

253

Conservative orthodontic treatment of mandibular bilateral condyle fracture.  

Science.gov (United States)

Maxillofacial trauma is rare in children younger than the age of 5 years (range 0.6%-1.2%), and they can require different clinical treatment strategies compared with fractures in the adult population because of concerns regarding mandibular growth and development of dentition. A 5-year-old girl with a history of falling from a bicycle 7 hours earlier was referred to the department of oral and maxillofacial surgery. Multislice computed tomographic examination demonstrated a bilateral fracture of the mandibular condyle neck associated with minimal fracture of the alveolar ridge of the maxilla. The multislice computed tomographic scan also demonstrated dislocation on the right condyle neck and, on the left side, a medial inclination of approximately 45 degrees associated with greenstick fracture of the right parasymphysis region. In this particular case, orthodontic rubber elastics in combination with fixed orthodontic brackets provided good results in the treatment of bilateral condyle neck fractures associated with greenstick fracture of parasymphysis. PMID:25098573

Gašpar, Goran; Brakus, Ivan; Kova?i?, Ivan

2014-09-01

254

Orthodontic rare earth magnets--in vitro assessment of cytotoxicity.  

Science.gov (United States)

The aim of this study was to assess and compare in vitro the cytotoxic effects of uncoated and parylene-coated rare earth magnets, used in orthodontics. Cytotoxicity of samarium-cobalt magnets (SmCo5 and Sm2Co17) and neodymium-iron-boron magnets (Nd2Fe14B) was assessed by two in vitro methods, the millipore filter method and an extraction method. Orthodontic stainless steel brackets served as controls. Uncoated SmCo5-magnets showed high cytotoxicity while uncoated Sm2Co17-magnets demonstrated moderate cytotoxicity. Uncoated neodymium-iron-boron magnets, as well as parylene coated Sm2Co17-magnets and parylene-coated neodymium-iron-boron magnets, showed negligible cytotoxicity. Short-term exposure to a static magnetic field did not cause any cytotoxic effect on the cells. PMID:7857892

Bondemark, L; Kurol, J; Wennberg, A

1994-11-01

255

Aspects of orthodontic-prosthetic rehabilitation of dentofacial anomalies.  

Science.gov (United States)

Skeletal class III malocclusion is one of the most difficult dentofacial anomalies, characterized by deviation in the development of the mandible and maxilla in the sagittal plane, where the mandible is dominant in relation to the maxilla. In patients with class III malocclusion, anomalies in the dentoalveolar level and esthetic discrepancies are also frequent. The etiology of class III malocclusion is multifactorial due to the interaction of hereditary and environmental factors. Rehabilitation and treatment of malocclusion is one of the major goals of modern dentistry. This article presents the orthodontic-prosthetic therapy and rehabilitation of a 45-year-old patient with an abnormal occlusal vertical dimension and a skeletal class III malocclusion. The patient came to the clinic complaining about degraded esthetics and disordered functions of the orofacial region (functions of eating, swallowing, speech) and also pain in the temporomandibular joint. After the diagnosis was made, the patient was first referred to orthodontic treatment with fixed orthodontic appliances (self-ligating brackets system Rot 0.22). Upon completion of the orthodontic treatment, the patient was sent for further prosthetic treatment. Fixed prosthetic restorations were made in the upper and lower jaw, thus achieving a satisfactory result in terms of esthetics and function of the stomatognathic system. PMID:23890094

Ajdukovi?, Zorica; Janoševi?, Mirjana; Filipovi?, Gordana; Arsi?, Stojanka; Janoševi?, Predrag; Petrovi?, Nenad

2014-04-01

256

Nambu brackets with constraint functionals  

CERN Document Server

If a Hamiltonian dynamical system with $n$ degrees of freedom admits $m$ constants of motion more than $2n-1$, then there exist some functional relations between the constants of motion. Among these relations the number of functionally independent ones are $s=m-(2n-1)$. It is shown that for such a system in which the constants of motion constitute a polynomial algebra closing in Poisson bracket, the Nambu brackets can be written in terms of these $s$ constraint functionals. The exemplification is very rich and several of them are analyzed in the text.

Tegmen, A

2006-01-01

257

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)

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.

Cláudio Pereira Viana

2005-06-01

258

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

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese 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.

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.

259

Six-month bracket failure rate evaluation of a self-etching primer.  

Science.gov (United States)

The aim of this study was to compare the clinical performance of a self-etching primer (SEP) with a conventional two-step etch and primer [conventional method (CM)]. The chair time required for bonding was also evaluated. Thirty-seven patients (14 males and 23 females) with a mean age of 16 years 5 months were included in the study. Six hundred and seventy-two brackets were bonded by one operator using a split-mouth design, with either SEP (Transbond Plus) or CM (Transbond XT). Bracket failure rates were estimated with respect to bonding procedure, dental arch, type of tooth (incisor, canine, and premolar), and gender. The results were evaluated using the chi-square test. The survival rate of the brackets was estimated with Kaplan-Meier analysis. Bracket survival distributions with respect to bonding procedure, dental arch, type of tooth, and patient gender were compared with a log-rank test. Bond failure interface was determined with the adhesive remnant index (ARI). The failure rates were 0.6 per cent for both bonding procedures. The failure and survival rates did not show significant differences between the bonding procedures, upper and lower dental arches, or gender. However, premolar brackets displayed a higher bond failure rate and a lower survival rate than incisor and canine brackets (P SEP was significantly shorter than with CM (P 0.05). The results of this in vivo, randomized, cross-mouth clinical trial demonstrated a high survival rate with Transbond Plus. This finding indicates that SEP can be effectively used for bonding of orthodontic brackets. PMID:18216373

Elekdag-Turk, Selma; Isci, Devrim; Turk, Tamer; Cakmak, Fethiye

2008-04-01

260

Friction: on the edge of fiction. A critique of bracket-archwire friction research protocols and their clinical relevance.  

Directory of Open Access Journals (Sweden)

Full Text Available The purpose of this article was to survey studies that have used in vitro experimental approaches to investigate frictional forces in the bracket-archwire complex during simulated orthodontic movement. A critical review of the research protocols adopted for the study of the foregoing system is provided, along with a discussion of the evidence supporting the proposed clinical implications for the tooth movement rate in vivo.

T. Eliades

1999-01-01

 
 
 
 
261

Development of a device to measure bracket debonding force in vivo.  

Science.gov (United States)

The purposes of this study were to develop a device to measure bracket debonding force in vivo and to evaluate, in vitro, the bond strength obtained with the device and with tensile and shear bond strength (SBS) tests performed in a universal testing machine. The device was developed using polypropylene pliers (3M Unitek). The basic principle consisted of measuring the applied force to debond, using two strain gauges (Kyowa) bonded to the region of major deformation of the plier handles. The crowns of 75 bovine incisors were embedded in acrylic resin and orthodontic brackets were bonded to the facial surface with Transbond XT (3M Unitek). In group A (n = 25) debonding was carried out with the device, while tensile bond strength testing was performed in group B (n = 25) and SBS testing in group C (n = 25). A universal testing machine (EMIC-DL-2,000) was used for these last two groups. According to analysis of variance and Tukey's test (alpha = 0.05), the mean bond strength for group C (7.71 MPa) was statistically higher than for groups A (2.98 MPa) and B (2.69 MPa). Groups A and B were not statistically different. The device was shown to be feasible to obtain in vivo bond strength values for orthodontic brackets, and that the bond strength values were dependent on the method and direction of debonding. PMID:17804426

Prietsch, José Renato; Spohr, Ana Maria; Lima da Silva, Isaac Newton; Pinheiro Beck, João Carlos; Silva Oshima, Hugo Mitsuo

2007-12-01

262

Notes on Super Nambu Bracket  

CERN Document Server

We formulate the super Nambu-Poisson algebra over a super manifold. The super Nambu bracket breaks the skew-symmetry in part. Some examples of the super Nambu-Hamilton system are given. We show that the divergence of super Nambu-Hamilton fields lead to a generalization of the Batallin-Vilkovski algebra.

Sakakibara, M

2002-01-01

263

Complications of orthodontic treatment: are soft drinks a risk factor?  

Science.gov (United States)

Soft drink consumption has steadily increased in recent decades in both western and developing countries. The trend is most apparent among children and adolescents. This rise in soft drink consumption has raised concerns among health care professionals, including dental practitioners. Accordingly, the effects of soft drinks on dental health have been investigated. Several studies have shown that dental problems, such as caries, enamel erosion, and corrosion of dental materials, may be associated with soft drink consumption. Because orthodontic appliances restrict toothbrush access, patients undergoing orthodontic treatment need special oral care and advice. This article reviews the risks and implications of soft drink consumption for orthodontic patients. PMID:19388431

Yip, Hilings H Y; Wong, Ricky W K; Hägg, Urban

2009-01-01

264

A Comparison of Apical Root Resorption in Incisors after Fixed Orthodontic Treatment with Standard Edgewise and Straight Wire (MBT Method  

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Full Text Available Statement of Problem: One of the major outcomes of orthodontic treatment is the apical root resorption of teeth moved during the treatment. Identifying the possible risk factors, are necessary for every orthodontist. Purpose: The aim of this study was to compare the rate of apical root resorption after fixed orthodontic treatment with standard edgewise and straight wire (MBT method, and also to evaluate other factors effecting the rate of root resorption in orthodontic treatments.Materials and Method: In this study, parallel periapical radiographs of 127 patients imaging a total of 737 individual teeth, were collected. A total of 76 patients were treated by standard edgewise and 51 patients by straight wire method. The periapical radiographs were scanned and then the percentage of root resorption was calculated by Photoshop software. The data were analyzed by Paired-Samples t-test and the Generalized Linear Model adopting the SPSS 15.0.Results: In patients treated with straight wire method (MBT, mean root resorption was 18.26% compared to 14.82% in patients treated with standard edgewise tech-nique (p< .05. Male patients had higher rate of root resorption,statistically significant (p< .05. Age at onset of treatment, duration of treatment, type of dental occlusion, premolar extractions and the use of intermaxillary elastics had no significant effect on the root resorption in this study.Conclusion: Having more root resorption in the straight wire method and less in the standard edgewise technique can be attributed to more root movement in pre-adjusted MBT technique due to the brackets employed in this method.

Zahed Zahedani SM.

2013-09-01

265

The effect of pretreatment with fluoride on the tensile strength of orthodontic bonding  

Energy Technology Data Exchange (ETDEWEB)

White spot decalcifications and caries occurring adjacent to bonded orthodontic brackets have long been a concern to orthodontists. One procedure suggested to overcome this problem is fluoride treatment prior to bonding. The purpose of this study was to compare the tensile bond strength of orthodontic self-cured resin from Concise on teeth rinsed 4 minutes in 1.23% APF with untreated controls. Measurements were made on an Instron machine. Debonding interfaces were observed with a scanning electron microscope and energy dispersive x-ray spectrometry. Distributions were calculated. The tensile bond strengths of the fluoride-treated teeth and the untreated teeth were not significantly different. The debonding interfaces between resin and bracket base, within the resin itself, and between enamel and resin were similar in the two experimental groups. However, greater enamel detachment was seen within the fluoride pretreatment group. So while fluoride pretreatment does not significantly affect tensile bond strength, it may cause enamel detachment after debonding.

Wang, W.N.; Sheen, D.H. (National Defense Medical Center, Taipei, Taiwan (China))

266

Release of Metal Ions from Orthodontic Appliances: An In Vitro Study  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In this paper, we report the results of an in vitro experiment on the release of metal ions from orthodontic appliances composed of alloys containing iron, chromium, nickel, silicon, and molybdenum into artificial saliva. The concentrations of magnesium, aluminum, silicon, phosphorus, sulfur, potassium, calcium, titanium, vanadium, manganese, iron, cobalt, copper, zinc, nickel, and chromium were significantly higher in artificial saliva in which metal brackets, bands, and wires used in orthod...

Mikulewicz, Marcin; Chojnacka, Katarzyna; Woz?niak, Barbara; Downarowicz, Patrycja

2012-01-01

267

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

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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 ...

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

2011-01-01

268

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)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese 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.

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

269

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  

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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.

Vanessa Nínia Correia Lima

2010-04-01

270

Cephalometry in orthodontic practice  

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Cephalometry is applied in orthodontic practice to: - obtain information on the growth of the skull - assist diagnosis of the relationship between the jaws and abnormalities in dentition - evaluate the results of treatment. The course of the diagnostic procedure with the aid of the Ricketts analysis and evaluation of the treatment results using five superimpositions is demonstrated by means of two examples. (Auth.)

271

Application of occlusal indices in orthodontic practice  

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Full Text Available Introduction. Occlusal indices were designed to improve diagnostic criteria and to enable an objective assessment of malocclusion severity. The aim of this study was to present the most frequently used occlusal indices in orthodontic practice and to determine their reliability when applied to dental models. Material and Methods. Three occlusal indices were selected for analysis: the Index of Orthodontic Treatment Need (IOTN, the Peer Assessment Rating Index (PAR and the Index of Complexity, Outcome and Need (ICON. Twenty dental models of patients referred to Department of Orthodontics, School of Dentistry, Belgrade, with malocclusions of different type and severity were used in this study. All dental models were measured by three afore mentioned indices twice, two months apart, in order to determine intraexaminer reliability. Results. The results showed that three indices had good reliability. Weighted Kappa was calculated for IOTN (0.72 and 0.79 for the aesthetic and the dental health component, respectively and root mean square error was calculated for PAR and ICON (2.1 and 4.5, respectively. There was no statistically significant difference in scores between two measurements of these two indices (p<0.01. Conclusion. Application of occlusal indices enables orthodontists to determine priorities in patient care, planning of orthodontic service, monitoring and promotion of standards. Occlusal indices are reliable diagnostic criteria.

?or?evi? Jelena

2009-01-01

272

Associations between pretreatment age and treatment time with orthodontic treatment outcome: A comparison by means of two orthodontic indices.  

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Full Text Available AIM: To compare the associations between pretreatment age and treatment time with orthodontic treatment outcome by means of two orthodontic indices.DESIGN: A retrospective analysis of treated patients.SETTING: The study was conducted at the accredited graduate Orthodontic Clinic of the University of Illinois at Chicago (UIC, USA.MATERIALS AND METHODS: The study casts of 100 treated orthodontic cases were randomly selected from the model store of the clinic without bias for age, gender or race.MAIN OUTCOME MEASURES: The pretreatment study casts and their corresponding post treatment casts were assessed using the original Peer Assessment Rating (PAR Index while the same post treatment study casts were also assessed using the American Board of Orthodontics Objective Grading System (ABO OGS, by a calibrated examiner. All the ABO OGS criteria were assessed except the radiographic component (root angulations. The associations were examined using chi-square tests.RESULTS: Using the PAR Index, statistically significant associations were found between orthodontic treatment outcomes and pre-treatment age (p = 0.010 as well as between orthodontic treatment outcome and treatment time (p = 0.035. No statistically significant associations were found between orthodontic treatment outcomes and pre-treatment age (p = 0.926 or treatment time (p = 0.900, according to the ABO OGS.CONCLUSION: Despite the general good finishes of the studied cases, the PAR Index was sensitive to the pretreatment age and treatment duration in assessing the quality of orthodontic treatment outcome unlike the ABO OGS.

Chukwudi Ochi Onyeaso

2008-01-01

273

Factorial designs: an overview with applications to orthodontic clinical trials.  

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Factorial designs for clinical trials are often encountered in medical, dental, and orthodontic research. Factorial designs assess two or more interventions simultaneously and the main advantage of this design is its efficiency in terms of sample size as more than one intervention may be assessed on the same participants. However, the factorial design is efficient only under the assumption of no interaction (no effect modification) between the treatments under investigation and, therefore, this should be considered at the design stage. Conversely, the factorial study design may also be used for the purpose of detecting an interaction between two interventions if the study is powered accordingly. However, a factorial design powered to detect an interaction has no advantage in terms of the required sample size compared to a multi-arm parallel trial for assessing more than one intervention. It is the purpose of this article to highlight the methodological issues that should be considered when planning, analysing, and reporting the simplest form of this design, which is the 2 × 2 factorial design. An example from the field of orthodontics using two parameters (bracket type and wire type) on maxillary incisor torque loss will be utilized in order to explain the design requirements, the advantages and disadvantages of this design, and its application in orthodontic research. PMID:23885023

Pandis, Nikolaos; Walsh, Tanya; Polychronopoulou, Argy; Katsaros, Christos; Eliades, Theodore

2014-06-01

274

Laser Applications in Orthodontics  

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Full Text Available A laser is a collimated single wavelength of light which delivers a concentrated source of energy. Soon after different types of lasers were invented, investigators began to examine the effects of different wavelengths of laser energy on oral tissues, routine dental procedures and experimental applications. Orthodontists, along with other specialist in different fields of dentistry, can now benefit from several different advantages that lasers provide during the treatment process, from the beginning of the treatment, when separators are placed, to the time of resin residues removal from the tooth surface at the end of orthodontic treatment. This article outlines some of the most common usages of laser beam in orthodontics and also provides a comparison between laser and other conventional method that were the standard of care prior to the advent of laser in this field.

Somayeh Heidari

2013-09-01

275

Comparison between two methods for resin removing after bracket debonding  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese 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.

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

276

Relationship between orthodontic treatment and gingival health: A retrospective study  

Science.gov (United States)

Objective: The aim of this retrospective study was to evaluate the relationship between orthodontic treatment and gingival health. Materials and Methods: A total of 251 patients among whom 177 were girls and 74 were boys, recruited from the records pool of the Department of Orthodontics, Faculty of Dentistry, University of Gazi, were included in the study. Patients’ treatments have been completed by postgraduate students during the period between 2006 and 2012. Patients’ folders were analyzed according to their age, treatment time, and the type of orthodontic treatment. Intra-oral photographs were analyzed, and the presence or absence of visible plaque, visible inflammation, and gingival recession were recorded, and incisor inclinations analyzed on lateral cephalometric films, before and after orthodontic treatment. Results: No statistically significant difference was found in patients treated with functional appliances before and after treatment. In patients treated with fixed orthodontic appliances, visible plaque, visible inflammation, and gingival recession showed significant increases after treatment, gingival biotype did not show any significant difference. Positive correlation was found between lower incisor position and gingival recession in patients treated with fixed appliance and extraction. And also cuspids were the teeth with the highest prevalence of gingival recession. Conclusion: Considering the relationship between orthodontic treatment and gingival health, cooperation among patients, orthodontists, and periodontists is important.

Boke, Fatma; Gazioglu, Cagri; Akkaya, Sevil; Akkaya, Murat

2014-01-01

277

Orthodontic movement of endodontically treated teeth: Contemporary views.  

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Full Text Available AIM: To collect and assess the contemporary data referring to orthodontic movement of endodontically treated teeth.METHOD: Relevant original and review articles were retrieved from PubMed, Medline, Cochrane, Embase, and Scopus databases, until February 2010. RESULTS: Endodontically treated teeth can be moved equally well to vital teeth and for the same distances, without more frequent adverse consequences. They present a smaller degree of apical resorption in mean values compared to vital teeth, however this difference is not regarded to be statistically or clinically significant. Root resorption seems to be related more to the severity of trauma and the stage of root development rather than orthodontic or surgical manipulations. The obturating material of choice in the event of endodontic treatment of teeth with incomplete apex as well as in cases of teeth with complete apex under orthodontic movement, seems to be Ca(OH2, because of the evidence based action of Ca(OH2 against the frequently observed root resorption. In cases of fractures, a 12 month waiting period is suggested before the start of orthodontic treatment, while in cases with no radiographic findings treatment can begin relatively immediately. CONCLUSIONS: Orthodontic movement of endodontically treated teeth is feasible without negative consequences to the apex. Orthodontic treatment prognosis of endodontically treated teeth depends on the type, the severity and the timing of trauma, as well as the management of the case by the team of therapists.

Ioulia Ioannidou-Marathiotou

2010-01-01

278

Relationship between self-concept and satisfaction with tooth alignment and demand for orthodontic treatment and professionally determined orthodontic needs  

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Full Text Available AbstractIntroduction: Recognition of psychological factors plays an important role in determination of orthodontic treatment needs as well as achieving a successful treatment. The aim of this study was to investigate the relationship between self-concept, dentofacial body image, subjective orthodontic treatment needs and professionally determined needs for orthodontic treatment among a group of university students.Materials and Methods: In this cross-sectional study, 164 students of Isfahan Faculty of Nursing and Midwifery were studied based on a simple sampling procedure. Data were collected using a standardized questionnaire consisting of 40 questions, including 3 parts for measurement of self-concept, dentofacial body image and self-perceived treatment need. Professionally determined orthodontic need was assessed using IOTN by two orthodontists. Data was analyzed using SPSS 11. Statistical methods for standardization of questionnaire, Cronbach's alpha, Student’s t-test and Spearman’s correlation were used at a significance level of 0.05.Results: Statistically significant correlations were seen between participants' self-concept, dentofacial body image, subjective orthodontic need and the professionally determined orthodontic need, with Spearman’s correlation coefficients of -0.16, 0.19 and -0.036, respectively (p value < 0.05.Conclusion: The majority of the students were satisfied with their teeth alignment and the more satisfied they were, the higher self-concept they had, with lower demand for orthodontic treatment. Moreover, the orthodontic needs determined by orthodontists were less among students with high self-concept. Key words: Health services needs and demand, Malocclusion, Self-assessment, Self-concept.

Amirreza Amnaie

2012-01-01

279

Nickel and cobalt hypersensitivity reaction before and after orthodontic therapy in children.  

Science.gov (United States)

Nickel and cobalt are major components of alloys used in orthodontics. The objectives of this cross-sectional study was to determine the prevalence of a nickel hypersensitivity reaction before and after orthodontic treatment with conventional stainless steel brackets and wires. The total sample consisted of 82 patients (55 females, and 27 males) from the Orthodontic Department at the Faculty of Dentistry, Süleyman Demirel University. A patch test and a questionnaire were used to evaluate hypersensitivity to these metals. The statistical analysis was carried out using Fisher's exact X(2) (2 x 2) test. The prevalence of nickel allergy was found to be higher in females than males (14.55% in females, 0% in males), and the prevalence of cobalt allergy was found to be 9.76% (7.27% in females, 14.81% in males). Orthodontic treatment with conventional stainless steel alloys does not appear to have an allergenic effect on the gingival and oral health of the patient. A family history of an allergy to these metals or the use of metallic objects in contact with the skin do not characterize nickel and cobalt hypersensitivity. This suggests orthodontic therapy with conventional stainless steel appliances does not initiate or aggravate a nickel hypersensitivity reaction. There was no association between the before treatment and after treatment to a nickel and cobalt hypersensitivity reaction. PMID:15558093

Saglam, Aynur Medine Sahin; Baysal, Vahide; Ceylan, A Murat

2004-11-15

280

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

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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.

José Rino Neto

2012-10-01

 
 
 
 
281

Interrelationships of endodontic- orthodontic treatments  

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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.

Khedmat S

2005-05-01

282

The effect of perturbations on resistance to sliding in second-order moments comparing two different bracket types  

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Orthodontic literature has shown all ligation methods to behave similarly in the clinical situation; however, the reasoning behind this still requires further investigation. A novel frictional device able to measure forces at the level of the bracket along with a custom perturbation device was used to investigate the effect of perturbations on resistance to sliding (RS) using conventional and passive ligated brackets. 150 3M Victory Series twins (0.022 slot) and 150 Damon Q brackets (0.022 slot) were tested using an 0.018 x 0.025 stainless steel wire for RS. There were 5 test groups consisting of equal numbers (n=30) representing combinations of high and low amplitude and frequency of perturbations along with a control. Second order angulation tested ranged from 0 to 6 degrees. Results for conventional brackets in the presence of perturbations at 0 degrees showed there was a statistically significant reduction (P<0.001) in RS when compared to controls. At 6 degrees, this difference (P<0.001) was seen in both high perturbation groups and one of the low perturbation groups. For passive ligated brackets, no statistically significant difference between groups was seen at 0 degrees. However, at 6 degrees high perturbation groups both resulted in statistically significant (P<0.001) reductions in RS when compared to controls. From this study it was concluded that passive ligated brackets have a lower RS when compared to conventional ligated brackets under all test conditions and angulations. Also, amplitude of perturbations has a larger role than frequency in reduction of RS values. PMID:25395993

Wong, Justin K; Romanyk, Dan L; Toogood, Roger W; Heo, Giseon; Carey, Jason P

2014-01-01

283

[Different orthodontic anchorage systems. A critical examination].  

Science.gov (United States)

Every orthodontic measure requires a detailed analysis of the individual anchorage situation in order to absorb (stationary anchorage) or control (reciprocal anchorage) the reactive forces and moments. Basically, an anchorage is oriented to the quality of the biological anchorage of the teeth. This is influenced by a number of factors: size of root surface, attachment level, density and structure of alveolar bone, periodontal reactivity, muscular activity, occlusal forces, craniofacial morphology and the nature of the tooth movement resulting from the planned correction. The quality of the biological anchorage may be enhanced by selective modification of the position of the anchor teeth: cortical anchorage of the first molar (Ricketts), distal inclination of the molars (Tweed, Begg) and differential torque control (Burstone). In this context, undesired anchorage effects also need to be discussed, for example interaction between the teeth being corrected and compact bone structures (symphysis menti, floor of the maxillary sinus) or the loss of anchorage by periodontal hyalinization or excessive friction within the bracket slot. In addition, the anchorage situation of ankylosed teeth and endosseous implants, as well as the advantages and disadvantages of additional mechanical anchorage aids (head-gear, Nance holding arch, lingual arch) are discussed. On the basis of the complexity of the individual biological and biomechanical aspects, guidelines are derived with which to establish anchorage control matched to the specific situation. PMID:8375786

Diedrich, P

1993-08-01

284

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

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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.

Paula Passalini

2010-06-01

285

Comparing orthodontic treatment need indexes  

Directory of Open Access Journals (Sweden)

Full Text Available

Background: Orthodontic Treatment Need Indexes are investigated to evaluate their validity criteria and their formulation on a scientific basis.

Methods: A bibliographic research was performed on Medline Database to find articles about orthodontic treatment need indexes published from 1960 to 2007. English language papers about criteria to establish indexes, their validity and reproducibility, and comparing two or more indexes were chosen.

Results: The study shows that orthodontic treatment need indexes are not based on evidence but are all based on the opinion of experts, although widely shared by the orthodontic community since the use of these indexes in clinical practice. The validity is assessed in terms of objectivity of the measurements needed to evaluate the clinical severity of the case under consideration. In this case, the quantitative methods seem to be more reliable and objective than the qualitative.

Conclusions: Currently in the orthodontic field the theory that orthodontic therapy is useful to prevent any disease in the patients is not supported by evidence based medicine. The recommendations about orthodontic treatment need should come from scientific debates, in order to support consensus based decisions.

Cristina Grippaudo

2008-09-01

286

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

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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.

Camila Ferraz

2012-10-01

287

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

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese 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.

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

288

An in vitro study to evaluate the effects of addition of zinc oxide to an orthodontic bonding agent  

Science.gov (United States)

Objective: The objective of this study is to test the antimicrobial effect of zinc oxide when incorporated into an orthodontic bonding material and to check the effect of addition of zinc oxide on the shear bond strength of the bonding material. Materials and Methods: Zinc oxide was added to a resin modified light cure glass ionomer cement (GIC) (Fuji Ortho LC GC America, Alsip, Ill) to make modified bonding agent containing 13% and 23.1% ZnO and the antimicrobial assay was done using agar disc diffusion method. Discs of the modified bonding agent were prepared and a culture of Streptococcus mutans mixed with soft agar was poured over it and incubated at 38°C for 48 h and zones of inhibition were measured. The test was repeated after a month to check the antimicrobial effect. In addition shear bond strength of the brackets bonded with the modified bonding agent was tested. Results: The agar disc showed zones of inhibition around the modified bonding agent and the antimicrobial activity was more when the concentration of ZnO was increased. The antimicrobial effect was present even after a month. The shear bond strength decreased as the concentration of ZnO increased. Conclusion: The incorporation of ZnO into a resin modified light cure GIC (Fuji Ortho LC GC America, Alsip, Ill) added antimicrobial property to the original compound. PMID:24966757

Jatania, Archana; Shivalinga, B. M.

2014-01-01

289

[White spot lesions and orthodontic treatment. Prevention and treatment].  

Science.gov (United States)

Decalcification of the enamel surface adjacent to fixed orthodontic appliances, in the form of white spot lesions, is a common and frequent well-known side-effect of orthodontic treatment. Fixed appliances and the bonding materials increase the retention of biofilm and encourage the formation of white spot lesions. Management of these lesions begins with a good oral hygiene regime and needs to be associated with use of fluoride agents (fluoridated toothpaste, fluoride containing mouth rinse, gel, varnish, bonding materials, elastic ligature), CPP-ACP, antiseptics, LASER, tooth whitening, resin infiltration, micro-abrasion. The purpose of this review is to access the direct evidence regarding the prevention and management of white spot lesions during and after orthodontic treatment. PMID:25158746

Morrier, Jean-Jacques

2014-09-01

290

Technical report for quality requirements establishment of in-chimney bracket  

Energy Technology Data Exchange (ETDEWEB)

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.

Kim, Kwan Hyun

2000-06-01

291

Poisson bracket relations for relativity groups  

CERN Document Server

Poisson bracket relations for generators of canonical transformations are derived directly from the Galilei and Poincare groups of changes of space-time coordinates. The method is simple but rigorous. The meaning of each step is clear because it corresponds to an operation in the group of changes of space-time coordinates. Only products and inverses are used; differences are not used. It is made explicitly clear why constants occur in some bracket relations but not in others, and how some constants can be removed, so that in the end there is a constant in the bracket relations for the Galilei group but not for the Poincare group. Problems are included.

Jordan, Thomas F

2008-01-01

292

The Current Concepts of Orthodontic Discrepancy Stability  

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Full Text Available There is a wide range of opinions on the best time to start orthodontic treatment but the vast majority is carried out on children who have lost all their baby (deciduous teeth and have most of their adult teeth (except for wisdom teeth present in the mouth. Stability of orthodontic discrepancy is one of the most important factors that determine when start orthodontic treatment of the dentofacial deformaties. This paper threw light on stability of orthodontic discrepancy, its classification, comparing between stable versus unstable orthodontic discrepancy and its impact on the timing of orthodontic treatment.

Maen Mahfouz

2014-04-01

293

Fricção em braquetes gerada por fios de aço inoxidável, superelásticos com IonGuard e sem IonGuard / Friction force on brackets generated by stainless steel wire and superelastic wires with and without IonGuard  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese OBJETIVO: o objetivo deste estudo foi verificar a fricção no braquete (Roth, Composite, 10.17.005, 3,2mm, largura 0,022" x 0,030", Torque -2° e angulação +13°, Morelli®, Brasil), utilizando fios ortodônticos retangulares de 0,019" x 0,025" de aço inoxidável (Morelli®, Brasil) e de níquel-titânio sup [...] erelásticos Bioforce com IonGuard e sem IonGuard (Bioforce, GAC®, EUA). MÉTODOS: foram utilizados 24 conjuntos braquetes/segmento de fio, divididos em 3 grupos de acordo com o fio. Cada conjunto braquete/segmento de fio foi testado 3 vezes e obtida uma média. Os ensaios foram realizados em máquina universal de ensaios EMIC DL2000®. Os dados foram submetidos à Análise de Variância com significância de 95%. RESULTADOS: o fio retangular Bioforce com IonGuard apresentou fricção significativamente menor que o Bioforce sem IonGuard, porém sem diferença do fio de aço inoxidável. Entretanto, o coeficiente de variação dos fios Bioforce com e sem IonGuard foi menor que o do fio de aço inoxidável. CONCLUSÃO: os fios retangulares de 0,019" x 0,025" Bioforce com IonGuard apresentam menor fricção que o fio Bioforce sem IonGuard, sem diferença para o fio de aço inoxidável. Abstract in english OBJECTIVE: The aim of this study was to evaluate the friction forces on brackets (Roth, Composite, 10.17.005, 3.2 mm, width 0.022" x 0.030 ", Torque -2° and angulation +13°, Morelli®, Brazil), with stainless steel orthodontic rectangular wire (Morelli®, Brazil) and nickel titanium superelastic Biofo [...] rce wires with and without IonGuard (Bioforce, GAC®, USA). MATERIAL AND METHODS: Twenty-four brackets/wire segment combinations were used, distributed into three groups according to the orthodontic wire. Each bracket/wire segment combination was tested three times. The tests were performed in a universal testing machine Emic DL2000®. The data was submitted to ANOVA one way followed by Tukey's post hoc test (p

Luiz Carlos Campos, Braga; Mario, Vedovello Filho; Mayury, Kuramae; Heloísa Cristina, Valdrighi; Sílvia Amélia Scudeler, Vedovello; Américo Bortolazzo, Correr.

294

Fricção em braquetes gerada por fios de aço inoxidável, superelásticos com IonGuard e sem IonGuard / Friction force on brackets generated by stainless steel wire and superelastic wires with and without IonGuard  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese OBJETIVO: o objetivo deste estudo foi verificar a fricção no braquete (Roth, Composite, 10.17.005, 3,2mm, largura 0,022" x 0,030", Torque -2° e angulação +13°, Morelli®, Brasil), utilizando fios ortodônticos retangulares de 0,019" x 0,025" de aço inoxidável (Morelli®, Brasil) e de níquel-titânio sup [...] erelásticos Bioforce com IonGuard e sem IonGuard (Bioforce, GAC®, EUA). MÉTODOS: foram utilizados 24 conjuntos braquetes/segmento de fio, divididos em 3 grupos de acordo com o fio. Cada conjunto braquete/segmento de fio foi testado 3 vezes e obtida uma média. Os ensaios foram realizados em máquina universal de ensaios EMIC DL2000®. Os dados foram submetidos à Análise de Variância com significância de 95%. RESULTADOS: o fio retangular Bioforce com IonGuard apresentou fricção significativamente menor que o Bioforce sem IonGuard, porém sem diferença do fio de aço inoxidável. Entretanto, o coeficiente de variação dos fios Bioforce com e sem IonGuard foi menor que o do fio de aço inoxidável. CONCLUSÃO: os fios retangulares de 0,019" x 0,025" Bioforce com IonGuard apresentam menor fricção que o fio Bioforce sem IonGuard, sem diferença para o fio de aço inoxidável. Abstract in english OBJECTIVE: The aim of this study was to evaluate the friction forces on brackets (Roth, Composite, 10.17.005, 3.2 mm, width 0.022" x 0.030 ", Torque -2° and angulation +13°, Morelli®, Brazil), with stainless steel orthodontic rectangular wire (Morelli®, Brazil) and nickel titanium superelastic Biofo [...] rce wires with and without IonGuard (Bioforce, GAC®, USA). MATERIAL AND METHODS: Twenty-four brackets/wire segment combinations were used, distributed into three groups according to the orthodontic wire. Each bracket/wire segment combination was tested three times. The tests were performed in a universal testing machine Emic DL2000®. The data was submitted to ANOVA one way followed by Tukey's post hoc test (p

Luiz Carlos Campos, Braga; Mario, Vedovello Filho; Mayury, Kuramae; Heloísa Cristina, Valdrighi; Sílvia Amélia Scudeler, Vedovello; Américo Bortolazzo, Correr.

2011-08-01

295

Review of properties and clinical applications of orthodontic wires.  

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Full Text Available During the last decades, a variety of alloys has been used in orthodontics to manufacture wires. The orthodontic clinician is called to select from a large number of materials that meet the biomechanical requirements of the clinical case to be treated. Mechanical properties of orthodontic wires are assessed by different laboratory tests, such as tensile, torsional, and bending tests. Although wire characteristics determined by such tests cannot be directly linked with their clinical application, they provide a basis for useful comparisons. The "ideal" wire characteristics have been specified by a number of authors. However, each wire may be considered ideal or not, depending on the targeted clinical outcome on each case. The clinician should know the properties and biomechanical behavior of available wires in order to choose the appropriate wire depending on the targeted outcome in different orthodontic treatment phases. The aim of this literature review is to summarize orthodontic wire properties and demonstrate their clinical applications as shown by their general properties. Stainless steel, cobalt-chromium, nickel-titanium, beta-titanium and multistranded wires are studied. Moreover, the so-called "aesthetic" wires are reviewed, as well as their potential development expected in the near future.

Ilias Mistakidis

2011-01-01

296

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

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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.

Ariana Pulido Guerrero

2010-03-01

297

Immunosuppressants: implications in Orthodontics  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english 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.

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

298

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

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese 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

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

2013-04-01

299

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

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese 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

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

300

The influence of fixed orthodontic appliances on masticatory and swallowing threshold performances.  

Science.gov (United States)

To test the hypothesis that treatment with orthodontic appliances disturbs masticatory and swallowing performances. Twenty-seven subjects with malocclusions requiring orthodontic treatment were included in this prospective study. The masticatory and swallowing performances were evaluated at five different times: before bracket placement (T0), immediately after archwire placement (T1), 48 h after archwire placement (T2), 30 days after archwire placement (T3) and 3 months after the initial appointment (T4). Masticatory performance was determined by the median particle sizes for the Optocal test food after 15 chewing strokes, and the swallowing thresholds were registered for both the test food and a natural food (peanuts). Pain during mastication was evaluated using a 100-mm visual analogue scale. Masticatory performance was significantly reduced at T2, at which time patients reported the highest pain values. The time spent to the first swallow was increased at T2 for the natural food but not for the test food. The values for pain, masticatory and swallowing performances at T3 and T4 were similar to those at T0. Orthodontic patient masticatory function is only reduced during the period of higher pain experience, which could also disrupt the deglutition of harder foods. However, neither mastication nor deglutition processes were disturbed by orthodontic appliances in long-term treatment. PMID:25155222

Magalhães, I B; Pereira, L J; Andrade, A S; Gouvea, D B; Gameiro, G H

2014-12-01

 
 
 
 
301

Problems in Standardization of Orthodontic Shear Bond Strength Tests; A Brief Review  

Directory of Open Access Journals (Sweden)

Full Text Available Bonding brackets to the enamel surface has gained much popularity today. New adhesive systems have been introduced and marketed and a considerable increase in research regarding bond strength has been published. A considerable amount of these studies deal with shear bond strength of adhesives designed for orthodontic purpose.Previous studies have used variety of test designs. This diversity in test design is due to the fact that there is no standard method for evaluating shear bond strength in orthodontics. Therefore comparison of data obtained from different study is almost impossible.This article tries to briefly discuss the developments occurred in the process of shear bond strength measurement of orthodontic adhesives with an emphasis on the type of test set up and load application.Although the test designs for measuring shear bond strength in orthodontics are still far from ideal, attempts must be made to standardize these tests especially in order to makecomparison of different data easier. It is recommended that test designs be set up in such a manner that better matches with the purpose of the study.

M.S. A. Akhoundi

2005-03-01

302

Preparation and evaluation of orthodontic setup  

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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.

Telma Martins de Araújo

2012-06-01

303

Orthodontics : in Africa or for Africa  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The Department of Orthodontics was founded in 1960 with an independent head of department. After 35 years it is appropriate to delineate the field of study of modern orthodontics and also to set course for the future. This inaugural address will contrast orthodontics for Africa in the context of a developing country with orthodontics in Africa in the context of a developed country. The department envisages playing an important role in training the healthcare workers who will provide commun...

Wiltshire, W. A.

1995-01-01

304

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

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english 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.

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

2012-10-01

305

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

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english 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

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

2010-03-01

306

Evaluation of Oxidative Stress Biomarkers in Patients with Fixed Orthodontic Appliances  

Science.gov (United States)

Aim. The aim of this study was to examine the changes in the levels of interleukine-1 beta (IL-1?), tumor necrosis factor alpha (TNF-?), malondialdehyde (MDA), nitric oxide (NO), and 8-hydroxydeoxyguanosine (8-OHdG) in saliva and IL-1?, TNF-?, and NO in gingival crevicular fluid (GCF) samples of patients with fixed orthodontic appliances. Material and Method. The subject population consisted of 50 volunteers who were in need of orthodontic treatment with fixed orthodontic appliances. GCF and saliva samples were obtained from all individuals before treatment, at 1st month of treatment and at 6th month of treatment. Periodontal clinical parameters were measured. Samples were investigated to detect IL-1?, TNF-?, and 8-OHdG levels using ELISA method and NO and MDA levels using spectrophotometric method. Results. Since IL-1? level detected in GCF at the 6th month of orthodontic treatment is statistically significant according to baseline (P < 0.05), all other biochemical parameters detected both in saliva and in GCF did not show any significant change at any measurement periods. Conclusion. Orthodontic tooth movement and orthodontic materials used in orthodontic treatment do not lead to a change above the physiological limits that is suggestive of oxidative damage in both GCF and saliva. PMID:24864131

Atug Ozcan, Sevil Sema; Ceylan, Ismail; Kurt, Nezahat; Dagsuyu, Ilhan Metin; Canakci, Cenk Fatih

2014-01-01

307

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

308

Orthodontic bonded retainers.  

Science.gov (United States)

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

Butler, Jonathan; Dowling, Paul

2005-01-01

309

Asymmetric extractions in orthodontics  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english 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.

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

310

Asymmetric extractions in orthodontics  

Directory of Open Access Journals (Sweden)

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.

Camilo Aquino Melgaço

2012-04-01

311

The Role and Efficacy of Herbal Antimicrobial Agents in Orthodontic Treatment  

Science.gov (United States)

Aims: To assess the effect of herbal antimicrobial agents on Streptococcus mutans count in biofilm formations during orthodontic treatment. Materials and Methods: We calculated the growth inhibition of oral bacteria in the orthodontic appliances after herbal antibacterial agents were placed in culture media. The Minimum Inhibitory Concentrations (MICs) of these agents on Streptococcus mutans growth were determined. After cultivating colonies of Streptococci in biofilm medium with these herbal antimicrobial agents and orthodontic attachments, viable cell counting was performed from the bacteria which were attached on them. Scanning electron microscopy (SEM) analysis of morphology was observed on bacterial cells which were attached to orthodontic attachments. The effects of these agents were then evaluated and recommendations were forwarded. Results: There was an increase in count of Streptococcus mutans with respect to the herbal antibacterial agents. Conclusion: Despite the antibacterial functions of these herbal agents, there was increase in the biofilm formation caused by Streptococcus mutans to orthodontic bands, which had occurred most likely through upregulation of glucosyl transferase expression. These extracts may thus play an important role in increased bacterial attachment to orthodontic wires. Thus, this study was corroborative of an amalgamation of Ayurvedic therapy and Orthodontic treatment. PMID:25121056

Mishra, Sumita; Kumar Sahu, Sanjeeb; Bhusan Nanda, Smruti; Charan Sahu, Kanhu

2014-01-01

312

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

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english 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.

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

2014-01-01

313

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

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english 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.

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