Recuperação do espaço protético com a utilização de mini-implantes / Prostetic space opening with the use of TADs

O controle da movimentação dentária, principalmente no sentido vertical, é um grande desafio mecânico no tratamento ortodôntico. Em pacientes adultos, é frequente a extrusão de dentes posteriores decorrente da perda do antagonista, com redução do espaço interoclusal necessário para a reabilitação protética. O objetivo do presente trabalho foi relatar um caso clínico, no qual foi realizada a intrusão dos dentes 14, 15, 16, 24, 25 e 26 por meio de dois mini-implantes vestibulares e um palatino, como ancoragem ortodôntica associada ao aparelho ortodôntico fixo. Tendo restabelecido o espaço protético adequado, a paciente foi encaminhada para fazer a reabilitação protética. Foi possível concluir que o uso de mini-implantes foi eficaz para a intrusão, tornando-se um valioso recurso para tratar a extrusão de dentes posteriores, decorrente de perdas dentárias no arco antagonista. (AU)

The control of dental movement, mainly in the vertical direction, is a great mechanical challenge in orthodontic treatment. Extrusion of posterior teeth is frequently observed due to the loss of the antagonist, with reduction of the interocclusal space necessary for prosthetic rehabilitation. The objective of the present study is to report a clinical case in which teeth 14, 15, 16, 24, 25 and 26 were intruded through two vestibular mini-implants and a palatine on both sides, as orthodontic anchorage associated with fixed orthodontic appliance. Upon re-establishment of the adequate prosthetic space, the patient was referred for prosthetic rehabilitation. It was possible to conclude that the use of mini-implants was effective for intrusion, making it a valuable resource to treat the extrusion of posterior teeth due to tooth losses in the antagonist arch. (AU)

Smile prevails over other facial components of male facial esthetics.

BACKGROUND: The aim of this study was to assess whether scores assigned to the eyes, nose, mouth, and chin regions work as predictors of full smiling face scores. METHODS: In this cross-sectional study, the authors used the facial photographs of 86 smiling men. Photographs yielded 5 components: 1 of the face itself and 4 subcomponents (eyes, nose, mouth, and chin region). Raters assigned the photographs beauty scores that the authors measured morphometrically. The authors analyzed the predictive ability of the subcomponents against that of the full face. RESULTS: The subcomponents were statistically significant predictors of facial beauty (mouth: r2 = 0.38, P < .0001; eyes: r2 = 0.14, P < .0001; chin region: r2 = 0.09, P < .0001; nose: r2 = 0.02, P = .05). The more beautiful people had several statistically significant characteristics, such as narrower faces. CONCLUSIONS: Facial subcomponents are predictive factors of the male smiling face and contribute in the following descending order of importance: mouth, eyes, chin region, and nose. PRACTICAL IMPLICATIONS: The results suggest that for many people improvement in smile esthetics also likely will exert a more positive effect on facial beauty than will other procedures (for example, rhinoplasty).

Citotoxicidade da resina acrílica com e sem adesivo temático para confecção da placa de Hawley / Acrylic resin cytotoxicity with and without thematic adhesive for hawley retainer

As placas de Hawley podem ser utilizadas como aparelhos passivos de contenção pós-movimentação ortodôntica, confeccionadas com resina acrílica e grampos de aço. Como todo aparelho removível, seu efeito depende da colaboração do paciente na sua utilização, principalmente de pacientes jovens. A confecção da placa de Hawley com adesivos temáticos surgiu com o objetivo de diminuir esse problema, motivando o paciente quanto ao seu uso. Avaliou-se, in vitro, a biocompatibilidade da resina acrílica com e sem adesivo temático. A citotoxicidade das resinas com e sem adesivos foi avaliada por meio de estudo colorimétrico em células L929, incubadas por 1, 2, 3 e 8 dias, em contato direto com corpos de prova. A quantificação das células viáveis foi realizada por espectrofotometria. Foi verificada baixa viabilidade celular nos dois grupos avaliados, com menores valores de absorbância no grupo das resinas com adesivo temático. Conclui-se que as resinas acrílicas com e sem adesivos temáticos apresentaram elevado grau de citotoxicidade, sendo que as resinas acrílicas sem adesivo apresentaram aumento na viabilidade celular após 8 dias, fator não observado nas resinas temáticas.(AU)

Hawley retainers are commonly used as a passive orthodontic appliance, made with acrylic resin and stainless steel clasps. Like any removable appliance, its effect depends on patient collaboration in its use, especially in young patients. Hawley's retainers with thematic adhesives came to motivate patient and minimize this problem. This study aimed to evaluate in vitro biocompatibility of the acrylic resin with and without the thematic adhesive. The resins cytotoxicity with and without adhesives was evaluated by means of a colorimetric study in L929 cells, incubated for 1, 2, 3, and 8 days, in direct contact with the samples. The viable cell quantification was performed by spectrophotometry. Low cell viability was observed in the two groups evaluated, with lower absorbance values in the resin group with thematic adhesive. It was concluded that acrylic resins with and without thematic adhesives presented high cytotoxicity. Adhesive-free acrylic resins presented an increase in cell viability after 8 days, which was not observed in resins with thematic adhesives. (AU)

Dentoskeletal and soft tissue changes in class II subdivision treatment with asymmetric extraction protocols.

BACKGROUND: This study cephalometrically compared the dentoskeletal and soft tissue changes consequent to one and three-premolar extraction protocols of class II subdivision malocclusion treatment. METHODS: A sample of 126 lateral cephalometric radiographs from 63 patients was selected and divided into two groups. Group 1 consisted of 31 type 1 class II subdivision malocclusion patients treated with asymmetric extractions of two maxillary premolars and one mandibular premolar on the class I side, with an initial mean age of 13.58 years. Group 2 consisted of 32 type 2 class II subdivision malocclusion patients treated with asymmetric extraction of one maxillary first premolar on the class II side, with an initial mean age of 13.98 years. t test was used for intergroup comparison at the pre- and posttreatment stages and to compare the treatment changes. RESULTS: Group 1 had greater maxillomandibular sagittal discrepancy reduction and greater maxillary first molar extrusion. Group 2 had mandibular incisor labial inclination and protrusion, and group 1 had mandibular incisor lingual inclination and retraction. Maxillary molar asymmetry increased in group 2, while mandibular molar asymmetry increased in group 1. CONCLUSIONS: The treatment changes produced by these two class II subdivision protocols are different to adequately satisfy the different needs for types 1 and 2 class II subdivision malocclusions.

Evaluation of cytotoxicity and corrosion resistance of orthodontic mini-implants.

OBJECTIVE:: To evaluate and compare in vitro cytotoxicity and corrosion resistance of mini-implants from three different commercial brands used for orthodontic anchorage. METHODS:: Six mini-implants (Conexão(tm), Neodent(tm) and SIN(tm)) were separately immersed in artificial saliva (pH 6.76) for 30 and 60 days. The cytotoxicity of the corrosion extracts was assessed in L929 cell cultures using the violet crystal and MTT assays, as well as cell morphology under light microscopy. Metal surface characteristics before and after immersion in artificial saliva were assessed by means of scanning electron microscopy (SEM). The samples underwent atomic absorption spectrophotometry to determine the concentrations of aluminum and vanadium ions, constituent elements of the alloy that present potential toxicity. For statistical analysis, one-way ANOVA/Bonferroni tests were used for comparisons among groups with p < 0.05 considered significant. Statistical analysis was carried out with Graph Pad PRISM software Version 4.0. RESULTS:: No changes in cell viability or morphology were observed. Mini-implants SEM images revealed smooth surfaces with no obvious traces of corrosion. The extracts assessed by means of atomic absorption spectrophotometry presented concentrations of aluminum and vanadium ions below 1.0 µg/mL and 0.5 µg/mL, respectively. CONCLUSION:: Orthodontic mini-implants manufactured by Conexão(tm), Neodent(tm) and SIN(tm) present high corrosion resistance and are not cytotoxic.

Evaluation of cytotoxicity and corrosion resistance of orthodontic mini-implants

ABSTRACT Objective: To evaluate and compare in vitro cytotoxicity and corrosion resistance of mini-implants from three different commercial brands used for orthodontic anchorage. Methods: Six mini-implants (Conexão(tm), Neodent(tm) and SIN(tm)) were separately immersed in artificial saliva (pH 6.76) for 30 and 60 days. The cytotoxicity of the corrosion extracts was assessed in L929 cell cultures using the violet crystal and MTT assays, as well as cell morphology under light microscopy. Metal surface characteristics before and after immersion in artificial saliva were assessed by means of scanning electron microscopy (SEM). The samples underwent atomic absorption spectrophotometry to determine the concentrations of aluminum and vanadium ions, constituent elements of the alloy that present potential toxicity. For statistical analysis, one-way ANOVA/Bonferroni tests were used for comparisons among groups with p < 0.05 considered significant. Statistical analysis was carried out with Graph Pad PRISM software Version 4.0. Results: No changes in cell viability or morphology were observed. Mini-implants SEM images revealed smooth surfaces with no obvious traces of corrosion. The extracts assessed by means of atomic absorption spectrophotometry presented concentrations of aluminum and vanadium ions below 1.0 µg/mL and 0.5 µg/mL, respectively. Conclusion: Orthodontic mini-implants manufactured by Conexão(tm), Neodent(tm) and SIN(tm) present high corrosion resistance and are not cytotoxic.

RESUMO Objetivo: avaliar, in vitro, e comparar a citotoxicidade e a resistência à corrosão de mini-implantes de três marcas comerciais diferentes, utilizados para ancoragem ortodôntica. Métodos: seis mini-implantes fabricados pelas empresas Conexão(r), Neodent(r) e SIN(r) foram imersos, separadamente, em saliva artificial (pH = 6,76), por 30 e 60 dias, de forma a obter os extratos da corrosão. A citotoxicidade dos extratos foi avaliada em cultura de células L929, empregando-se a análise de ensaios do cristal violeta e MTT, bem como da morfologia celular sob microscopia óptica. As características da superfície do metal antes e após a imersão em saliva artificial foram avaliadas usando microscopia eletrônica de varredura. Os extratos foram submetidos a espectrofotometria de absorção atômica, para determinar as concentrações dos íons alumínio e vanádio, elementos constituintes da liga e que apresentam toxicidade em potencial. Para análise estatística, os testes one-way ANOVA/Bonferroni foram usados para comparação entre os grupos, com p < 0,05 sendo considerado significativo. A análise estatística foi realizada com o programa Graph Pad PRISM v. 4.0. Resultados: não foi observada alteração na viabilidade ou morfologia celular após a exposição dos mini-implantes aos extratos. A análise dos mini-implantes por microscopia eletrônica de varredura revelou superfícies lisas e sem traços evidentes de corrosão. Os extratos analisados usando espectrofotometria de absorção atômica apresentaram concentrações de íons alumínio e vanádio inferiores a 1,0 µg/ml e 0,5 µg/ml, respectivamente. Conclusão: os mini-implantes fabricados pelas empresas Conexão(r), Neodent(r) e SIN(r) apresentam alta resistência à corrosão e não são citotóxicos.

Estudo da alteração dimensional linear dos elásticos ortodônticos em diferentes pigmentos e tempos de armazenamento / Study of linear dimensional change of orthodontic elastics in different pigments and storage times

O objetivo deste trabalho foi avaliar a alteração dimensional linear dos elásticos ortodônticos sendo submetidos ao tempo de armazenagem em saliva artificial a 37ºC durante o período imediato (T0), 24 horas (T24) e 30 dias (T30). Os grupos de elásticos foram divididos em cinco cores com dez (n=10) amostras por grupo: cinza (C); verde (V); preta (P); rosa (R) e transparentes (T), e marcas comerciais: Morelli (a); 3M Unitek (b); GAC (c). Utilizou-se a máquina de análise de dimensão (perfilômetro) da marca Mitutoyo, que avaliou a alteração de dimensão conforme as distâncias de extremidade dos elásticos e os fatores envolvidos como o tempo de armazenamento e a marca comercial. Em seguida, os dados foram analisados estatisticamente, obtendo os resultados e realizadas as tabelas, gráficos e as correlações lineares. Para esta avaliação foram utilizados os testes Anova e de Tukey (p < 0,01). Os resultados apontaram os seguintes valores: grupo V ­ t0:3,09 (± 0,24), t24:3,12 (± 0,36) e t30d:3,15 (± 0,22); grupo T ­ t0:3,07 (± 0,16), t24:3,10 (± 0,15), t30d:3,14 (± 0,10), grupo P ­ t0:3,13 (± 0,24), t24:,16 (± 0,19), t30d:3,18 (± 0,20); grupo R ­ t0:3,08 (± 0,25), t24:3,11 (± 0,14), t30d:3,13 (± 0,18); grupo C ­ t0:3,15 (± 0,31), t24h:3,18 (± 0,15) e t30d:3,19 (± 0,59). O grupo P apresentou diferença estatisticamente significante em relação aos demais. As marcas comerciais apresentaram pequenas alterações dimensionais, aceitáveis clinicamente de acordo com a literatura. Concluiu-se que os pigmentos, que determinam a cor específica dos elásticos, são fatores que interferem na propriedade deste material. O tempo de armazenamento é determinante e fundamental para avaliação do comportamento de estabilidade do material polimérico.

The objective of this study was to evaluate the linear dimensional change of orthodontic elastics submitted to the storage in artificial saliva 37ºC at baseline (T0), 24-hour (T24), and at 30-day (T30) periods. The groups (n=10) were divided into five colors: gray (C), green (V), black (P), pink (R), and clear (T) with the following brands: Morelli (a), 3m Unitek (b), and GAC (c). A profilometer (Mitutoyo) was used to analyze the dimensional changes. Next, means were obtained also with tables, plots, and linear correlations. The Anova and Tukey´s tests (p<0.01) were used to evaluate data. The results showed that group V presented values: t0:3.09 (± 0.24), t24:3.12 (± 0.36) and t30d:3.15 (± 0.22); T group: t0:3.07 (± 0.16), t24:3.10 (± 0.15), t30d:3.14 (± 0.10), P group: t0:3.13 (± 0.24), t 24:16 (± 0.19), t30d:3.18 (± 0.20); R group: t0:3.08 (± 0.25), t24:3.11 (± .14), t30d:3.13 (± 0.18), C group: t0:3.15 (± 0.31), t24h:3.18 (± 0.15) and t30d: 3.19 (± 0.59), being statistically different from the P group compared to other groups. The commercial brands presented small dimensional changes and according the literature. It can be concluded that pigments can interfere with the elastic property.The storage time is fundamental to evaluate the stability of the polymeric material.

Avaliação microscópica de fios ortodônticos de NiTi revestidos com polímero / Microscopic evaluation of polymer-coated NiTi orthodontic archwires

Objetivo: avaliar microscopicamente a superfície de fios de NiTi revestidos por polímeros. Material e métodos: foram selecionadas quatro marcas de fios estéticos, divididas em quatro grupos: G1 (Tecnident); G2 (TP Orthodontics); G3 (Trianeiro) e G4 (Morelli). Os grupos foram analisados por meio de microscopia eletrônica de varredura (MEV), e os resultados analisados por meio do índice de irregularidades. Resultados: os grupos em ordem crescente de irregularidades foram: Morelli, Tecnident, Trianeiro e TP Orthodontics.

Objective: to microscopically evaluate the surface of polymercoated NiTi archwires: Material and methods: four brands were selected in this study: G1 (Tecnident), G2 (TP Orthodontics); G3 (Trianeiro) and G4 (Morelli). The specimens were investigated under SEM and the results provided as irregularity indexes. Results: the irregularity indexes were classified in the following ascending order: Morelli, Tecnident, Trianeiro, and TP Orthodontics.

Avaliação da degradação da força liberada por ligaduras elásticas convencionais e temáticas / Force degradation assessment released by conventional and thematic orthodontic elastic ties

As ligaduras elásticas são consideradas importantes fontes de força na movimentação ortodôntica. No entanto, apresentam a desvantagem de não serem capazes de liberar níveis de forças constantes no meio bucal, por sofrerem alterações em suas propriedades físicas (dimensão, características individuais), prejudicando suas propriedades mecânicas. O objetivo deste trabalho foi avaliar a degradação de força das ligaduras elásticas ortodônticas convencionais e temáticas. Dezoito grupos experimentais foram avaliados (n=10), tendo como fatores em estudo o formato das ligaduras, temática (Orthosource) e convencional (Morelli); o tempo de armazenagem em saliva artificial a 37°C (24 horas e 30 dias) e a cor (vermelho, rosa e azul). Para a determinação da intensidade das forças liberadas, todas as ligaduras elásticas foram distendidas quatro vezes o valor do seu comprimento original (1 mm), em máquina de ensaio universal Instron 5965 à velocidade constante de 5,08 mm/min, sendo a resistência máxima à tração registrada em N. Os dados foram analisados pelos testes Anova e Tukey para comparações entre os grupos (α=0,05). Os resultados demonstraram que a degradação de força após 24 horas foi muito superior nas ligaduras elásticas convencionais (24,09%, 18,90% e 14,45%) do que nas ligaduras temáticas (1,31%, 2,55% e 2,99%) nas cores vermelho, rosa e azul, respectivamente. Após 30 dias, a degradação de força continuou sendo superior nas ligaduras elásticas convencionais (33,20%, 27,23% e 21,87%), embora a degradação nas ligaduras temáticas tenha aumentado drasticamente neste período (11,89%, 15,55% e 18,53%) nas cores vermelho, rosa e azul, respectivamente...

Elastic ties are considered an important source of force for orthodontic movement. However, they present the disadvantage of not being able to release constant force levels overtime in the oral environment due to changes in their physical properties (dimension, individual characteristics) affecting their mechanical properties. The purpose of this study was to evaluate the force degradation of conventional and thematic orthodontic elastic ties. Eighteen experimental groups were evaluated (n=10) having as variables the elastic tie format of two commercial brands, thematic (Orthosource) and conventional (Morelli), the storage time in artificial saliva at 37°C (immediate, 24 hours and 30 days) and color (red, pink and blue). To determine the magnitude of the forces released, all elastic ties were stretched four times their original size (1 mm) in a universal testing machine (Instron 5965) at a constant speed rate of 5.08 mm/min with the tensile strength measured in N. The data were analyzed by Anova and Tukey statistical tests for multiple comparisons among the groups (α=0.05). The results demonstrated that force degradation after 24h was much greater for the conventional (24,09%, 18,90% and 14,45%) than for the thematic elastic ties (1,31%, 2,55% and 2,99%) in red, pink and blue colors, respectively. After 30 days, force degradation continued to be greater with the conventional elastic ties (33,20%, 27,23% and 21,87%) although force degradation with the thematic elastic ties increased dramatically (11,89%, 15,55% and 18,53%) in red, pink and blue colors, respectively...

Radiographic evaluation of orthodontic treatment by means of four different cephalometric superimposition methods.

INTRODUCTION: Despite discussion on the merit of various cephalometric superimposition methods, there remains a need to assess which one can be used in daily practice with reasonably accuracy and less working time. OBJECTIVE: The aim of this study was to investigate four methods of cephalometric superimposition by means of assessing the longitudinal changes in craniofacial morphology caused by growth and response of adolescents with Class I malocclusion to orthodontic treatment involving first premolar extraction. METHODS: Pretreatment (T1) and post-treatment (T2) standardized lateral cephalometric radiographs of 31 adolescents (20 females and 11 males), with Angle Class I malocclusion and indication of premolar extraction, participated in this study. Radiographs were digitized, traced and had structures identified by means of a cephalometric software. Four superimposition methods were used: Björk structural method, Steiner/Tweed SN line, Ricketts N-Ba line at N-point and Ricketts N-Ba line at CC-point. Positional changes were quantified by horizontal and vertical linear changes in the following cephalometric landmarks: anterior/posterior nasal spine (ANS and PNS), gnathion (Gn), Gonion (Go), Pogonion (Pog), A-point and B-point. Differences between T1 and T2 in horizontal and vertical positional changes for all superimposition methods were assessed by one-way analysis of variance (ANOVA) and Bonferroni correction (p < 0.05). RESULTS: There were no statistically significant differences among the cephalometric superimposition methods or when patients' sex was considered. CONCLUSION: Björk structural method, Steiner/Tweed SN line, Ricketts N-Ba line at N-point and Ricketts N-Ba line at CC-point methods were reliable and presented similar precision when the overall facial changes due to active growth and/or orthodontic treatment were examined.

Radiographic evaluation of orthodontic treatment by means of four different cephalometric superimposition methods

INTRODUCTION: Despite discussion on the merit of various cephalometric superimposition methods, there remains a need to assess which one can be used in daily practice with reasonably accuracy and less working time. OBJECTIVE: The aim of this study was to investigate four methods of cephalometric superimposition by means of assessing the longitudinal changes in craniofacial morphology caused by growth and response of adolescents with Class I malocclusion to orthodontic treatment involving first premolar extraction. METHODS: Pretreatment (T1) and post-treatment (T2) standardized lateral cephalometric radiographs of 31 adolescents (20 females and 11 males), with Angle Class I malocclusion and indication of premolar extraction, participated in this study. Radiographs were digitized, traced and had structures identified by means of a cephalometric software. Four superimposition methods were used: Björk structural method, Steiner/Tweed SN line, Ricketts N-Ba line at N-point and Ricketts N-Ba line at CC-point. Positional changes were quantified by horizontal and vertical linear changes in the following cephalometric landmarks: anterior/posterior nasal spine (ANS and PNS), gnathion (Gn), Gonion (Go), Pogonion (Pog), A-point and B-point. Differences between T1 and T2 in horizontal and vertical positional changes for all superimposition methods were assessed by one-way analysis of variance (ANOVA) and Bonferroni correction (p < 0.05). RESULTS: There were no statistically significant differences among the cephalometric superimposition methods or when patients' sex was considered. CONCLUSION: Björk structural method, Steiner/Tweed SN line, Ricketts N-Ba line at N-point and Ricketts N-Ba line at CC-point methods were reliable and presented similar precision when the overall facial changes due to active growth and/or orthodontic treatment were examined. .

INTRODUÇÃO: apesar dos debates sobre os méritos dos vários métodos de sobreposição cefalométrica, ainda há necessidade de se avaliar quais deles poderiam ser utilizados na prática diária, com razoável precisão e menor tempo de trabalho. OBJETIVO: o objetivo desta pesquisa foi investigar quatro métodos de sobreposição cefalométrica, avaliando as mudanças longitudinais na morfologia craniofacial causadas pelo crescimento e resposta ao tratamento, em adolescentes com má oclusão de Classe I tratados ortodonticamente com extração de primeiros pré-molares. MÉTODOS: foram usadas telerradiografias laterais pré-tratamento (T1) e pós-tratamento (T2) de 31 adolescentes (20 do sexo feminino e 11 do sexo masculino), com Classe I de Angle e indicação de extração de pré-molares. As radiografias foram digitalizadas, traçadas e as estruturas, identificadas com um software cefalométrico (Radiocef, Radio Memory, Belo Horizonte, Brasil). Quatro métodos de sobreposição foram utilizados para avaliar mudanças de posição devidas ao crescimento e/ou tratamento: método Estrutural de Björk; método Steiner/Tweed linha SN; Ricketts linha N-Ba no ponto N; e Ricketts linha N-Ba no ponto CC. As mudanças posicionais avaliadas pelos métodos de sobreposição foram quantificadas por mudanças lineares horizontais e verticais nos seguintes pontos cefalométricos: espinha nasal anterior (ENA), espinha nasal posterior (ENP), gnátio (Gn), Gônio (Go), Pogônio (Pog), Ponto A e Ponto B. Mudanças de posição horizontal e vertical entre T1 e T2 para todos os métodos de sobreposição foram avaliadas por análise de variância (ANOVA) e teste de Bonferroni (p < 0,05). RESULTADOS: não houve diferença estatística significativa entre os métodos de sobreposição cefalométrica em toda a amostra ou quando o sexo dos pacientes foi considerado. CONCLUSÃO: de acordo com a metodologia aplicada nesse estudo, os métodos de sobreposição cefalométrica Estrutural de Björk, de Steiner/Tweed linha SN, ...

Avaliação da resistência ao cisalhamento de tubos de colagem ortodônticos / Shear bond strength evaluation of orthodontic molar tubes

O objetivo do presente trabalho é avaliar a resistência ao cisalhamento de tubos de colagem ortodônticos de diferentes marcas comerciais. Foram utilizados 30 tubos de colagem ortodônticos divididos em cinco grupos (n = 6): I (Rocky Mountain Orthodontics, Colorado, USA), II (Ormco Corporation, Glendora, Califórnia), III (3M-Unitek, Minnesota, USA), IV (G&H Wire Company, Hanover, Alemanha) e V (Dentsplay GAC International, NY, USA). Os mesmos foram colados no ponto mais convexo e centralizados na face do dente bovino e levados à máquina universal de ensaios mecânicos Emic DL 2000, a uma velocidade de 0,5 mm por minuto. Foi avaliada a força necessária para descolar os tubos ortodônticos. Os dados foram analisados pela análise de variância (ANO-VA) e teste de Fisher. Os tubos ortodônticos do grupo III necessitaram de uma força maior para que ocorresse a descolagem, esses resultados foram estatisticamente significantes em relação aos demais (p < 0,01), que se descolaram com força menor. O grupo IV apresentou os menores valores para descolar, entretanto, sem diferença estatística com o grupo V (p > 0,01). Conclui-se que tubos ortodônticos podem ser utilizados como alternativa para a bandagem dos molares. Três das cinco marcas comerciais suportaram tanto a força ortodôntica como a mastigatória, enquanto que duas marcas comerciais suportaram somente as forças ortodônticas.

The purpose of this study is to evaluate the shear bond strength (SBS) of orthodontic molar tubes from different trademarks. Thirty molar tubes were divided into five groups (n = 6): I (Rocky Mountain Orthodontics, Colorado, USA), II (Ormco Corporation, Glendora, Califórnia), III (3M-Unitek, Minnesota, USA), IV (G&H Wire Company, Hanover, Alemanha) e V (Dentsplay GAC International, NY, USA). The tubes were bonded to bovine teeth and placed on an Emic DL2000 testing machine with a crosshead speed of 0.5 mm/minute. The amount of force required to debond the tubes was assessed. Data were analyzed using two-way variance analysis (ANOVA) and the Fisher test. There was a statistically significant difference (p < 0.001) on shear bond strength. Othodontic tubes of group III presented thehigher SBS, while group IV showed the lower SBS, with no statistical difference in relation to group V (p > 0.01). It was concluded that bonding tubes may be used as an alternative to molar bands. Three of the five brands assessed in this study, supported both, orthodontic and masticatory forces, while two of them supported only the orthodontic forces.

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

OBJECTIVE: To evaluate the bonding strength of the ceramic bracket and composite resin restoration interface, using four types of treatment on the base of the bracket. METHODOLOGY: 48 photoactivated composite resin discs were used (FiltekTM Z250) contained in specimens and divided into 4 groups of 12 specimens for each group according to the type of treatment performed on the base of the brackets. Once the brackets were bonded, the specimens were subjected to shear stress carried out in a universal testing machine (MTS: 810 Material Test System) calibrated with a fixed speed of 0.5 mm / minute. The values obtained were recorded and compared by means of appropriate statistical tests - analysis of variance and then Tukey's test. RESULTS AND CONCLUSIONS: The surfaces of ceramic brackets conditioned with 10% hydrofluoric acid for 1 minute, followed by aluminum oxide blasting, 50µ, after silane application and primer application, was considered the best method to prepare surfaces of ceramic brackets prior to orthodontic esthetic bonding.

OBJETIVO: avaliar a resistência à união da interface entre braquete cerâmico e restauração de resina composta, empregando quatro tipos de tratamento na base do braquete. MÉTODOS: foram utilizados 48 discos de resina fotoativada (Filtek® Z250) incluídos em corpos de prova, divididos em quatro grupos, com 12 espécimes em cada grupo, de acordo com o tipo de tratamento realizado na base do braquete. Uma vez colados os braquetes, os corpos de prova foram submetidos à tensão de cisalhamento, realizado numa máquina universal de ensaios (MTS: 810 Material Test System) calibrada com velocidade fixa de 0,5mm/min. Os valores obtidos foram registrados e comparados por meio de médias, utilizando-se testes estatísticos adequados (análise de Variância e, posteriormente, teste de Tukey). RESULTADOS E CONCLUSÕES: o condicionamento das superfícies dos braquetes cerâmicos com ácido hidrofluorídrico a 10% por 1 minuto, seguido do jateamento com óxido de alumínio com 50um de tamanho, e posterior aplicação do silano e, depois, aplicação de adesivo, foi considerado o melhor método para o preparo de superfícies de braquetes cerâmicos previamente à colagem estética ortodôntica.

Influence of ceramic surface treatment on shear bond strength of ceramic brackets.

OBJECTIVE: To compare four different surface treatment methods and determine which produces adequate bond strength between ceramic brackets and facets of porcelain (feldspathic), and evaluate the Adhesive Remnant Index (ARI) scores. MATERIALS AND METHODS: Ten facets of porcelain specimens with glazed surfaces were used for each group. The specimens were randomly assigned to one of the following treatment conditions of the porcelain surface: (1) no surface treatment (control group), (2) fine diamond bur + orthophosphoric acid gel 37%, (3) hydrofluoric acid (HFL) 10%, and (4) HFL 10% + silane. Ceramic brackets were bonded with the adhesive cement Transbond XT. The shear bond strength values were measured on a universal testing machine at a crosshead speed of 0.5 mm/min. RESULTS: There was a significant difference (P<0.05) between the control group and all other groups. There was no significant difference (P<0.05) between treated porcelain surface with diamond bur + orthophosphoric acid gel 37% (4.8 MPa) and HFL 10% (6.1 MPa), but the group treated with HFL 10% had clinically acceptable bond strength values. The group treated with HFL 10% + silane (17.5 MPa) resulted in a statistically significant higher tensile bond strength (P<0.05). In group 4, 20% of the porcelain facets displayed damage. CONCLUSION: Etching of the surface with HFL increased the bond strength values. Silane application was recommended to bond a ceramic bracket to the porcelain surface in order to achieve bond strengths that are clinically acceptable.

Utilização de documentação ortodôntica na identificação humana / Use of orthodontic records in human identification

OBJETIVO: o objetivo deste trabalho é relatar um caso pericial onde um indivíduo encontrado carbonizado foi identificado utilizando-se as informações presentes na sua documentação ortodôntica. MÉTODOS: um indivíduo do sexo masculino foi encontrado carbonizado no interior de um automóvel. Após a realização dos exames periciais no local, exames necroscópicos e radiográficos no Instituto Médico-Legal, identificou-se que a vítima utilizava aparelho ortodôntico fixo, possuía dentes supranumerários nas quatro hemiarcadas, terceiros molares semi-inclusos e restaurações de amálgama em determinadas faces de diversos dentes. Como os tecidos moles do indivíduo apresentavam-se bastante destruídos, uma identificação pela análise das impressões digitais tornou-se inviável. Após a entrega da documentação ortodôntica pela família, foi feita a análise do prontuário clínico, radiografias, fotografias intra e extrabucais e modelos de gesso - confrontando-se essas informações com as obtidas anteriormente. RESULTADOS E CONCLUSÕES: o confronto odontolegal revelou 20 pontos concordantes do exame necroscópico e da documentação ortodôntica, permitindo a determinação de uma correlação positiva entre o cadáver examinado e a identidade da pessoa desaparecida, tornando-se desnecessária a realização de outros exames para a identificação da vítima (exame de DNA).

OBJECTIVE: This study describes a forensic case of incinerated remains of a man that were identified using information found in his orthodontic records. METHODS: Incinerated remains of a man were found inside a car. After forensic crime scene investigation and postmortem and radiographic exams in the Forensic Department, forensic experts found that the victim had a fixed orthodontic appliance, supernumerary teeth in all quadrants, partially erupted third molars and amalgam restorations in some surfaces of several teeth. As the individual's soft tissues were substantially destroyed, identification using fingerprints was not the ideal choice. After orthodontic records were handed in by the family, his clinical chart, radiographs, intra- and extraoral photographs and impressions were analyzed, and these data were compared with previously collected information. RESULTS AND CONCLUSIONS: Forensic dentistry examination revealed 20 concordant points in specimen examination and orthodontic records, which enabled the establishment of a positive correlation between the cadaver under examination and the missing person and eliminated the need for further analyses (DNA tests) to identify the victim.

Esthetic effect of orthodontic appliances on a smiling face with and without a missing maxillary first premolar.

INTRODUCTION: In this study, we evaluated the effects of orthodontic appliances and an extracted maxillary first premolar on the esthetic evaluation of a smiling face according to the perceptions of orthodontists and laypeople. METHODS: Standardized oblique photographs of a young woman with a pleasing smile were taken. The photos were edited by using digital imaging software to produce 10 combinations of presence or absence of orthodontic appliances with either esthetic or metal brackets, rubber bands of different colors, and presence or absence of the maxillary first premolar. Two groups of 50 observers each, 1 of laypeople and the other of orthodontists, evaluated the images and assigned esthetic scores to the smiles according to a visual analog scale. RESULTS: The presence of orthodontic appliances and metal brackets, regardless of rubber band color, had no negative effect on the esthetic evaluation of the smile by either group. Appliances with esthetic brackets were significantly less pleasing for laypeople, whereas for orthodontists they did not affect the esthetic evaluation of the smile. The extraction space had a significantly negative effect on the evaluation of the smile, and only orthodontists thought that the appliance minimized its effect. CONCLUSIONS: The type of bracket used with the orthodontic appliances and a maxillary first premolar extraction space produced different esthetic perceptions in laypeople and orthodontists.

Bond strength of metallic brackets after dental bleaching.

OBJECTIVE: To test the hypothesis that there is no difference between the action of at-home and in-office vital bleaching on the shear bond strength of metallic brackets bonded with composite resin 24 hours after bleaching. MATERIALS AND METHODS: Forty-five human upper premolars were randomly divided into three groups: (1) control, (2) 10% carbamide peroxide at-home bleached, and (3) 35% hydrogen peroxide in-office bleached. Twenty-four hours after bleaching the teeth were pumiced, bonded with metallic brackets, and stored in distilled water. One day after bonding the shear bond strength of the brackets was determined. RESULTS: The mean shear bond strength of Group 1 (control) and Group 2 (carbamide peroxide bleached) were not statistically different. Group 3 (hydrogen peroxide bleached) had a significantly lower mean shear bond strength than Group 1 and Group 2. CONCLUSIONS: The hypothesis is rejected. Use of 10% carbamide peroxide bleaching does not significantly alter shear bond strength values. On the other hand, use of 35% hydrogen peroxide bleaching significantly reduces these values and diminishes the amount of resin remnant on the tooth surface after bracket debonding.

Utilização de auxiliares odontológicos em Ortodontia: implicações éticas e legais / Utilization of dental assistants in Orthodontics: ethics and legal implications

INTRODUÇÃO: o mercado de trabalho tem se mostrado saturado de profissionais atuando nos grandes centros urbanos e, por este motivo, as estratégias de produtividade são imprescindíveis. A delegação de funções aos auxiliares odontológicos tem se tornado vital e corriqueira para aqueles que exercem a Ortodontia. OBJETIVO: conhecer o perfil do cirurgião-dentista especialista nesta área e as funções delegadas por ele à equipe auxiliar. METODOLOGIA: foi aplicado um questionário a todos os especialistas em Ortodontia e Ortopedia Facial inscritos no Conselho Regional de Odontologia de Goiás, com atividade em Goiânia e Aparecida de Goiânia. RESULTADOS E CONCLUSÃO: os resultados demonstraram que os ortodontistas, de um modo geral, aproveitam bem a mão-de-obra auxiliar chegando até a ultrapassar os limites ético-legais.

INTRODUCTION: the work market has been shown to be saturated with professionals working at large urban centers and, for this reason, productive strategies are indispensable. The delegation of functions to dental assistants is becoming vital and quite common for those that work with Orthodontics. AIM: to evaluate the profile of the orthodontists and the workload delegated by them to the dental assistant team. METHODS: a questionnaire was given to all specialists in Orthodontics and Dentofacial Orthopedics registered at the Regional Council of Dentistry of Goiás, with practices in Goiânia and Aparecida de Goiânia. RESULTS AND CONCLUSIONS: the results demonstrated that orthodontists, in general, take advantage of the work labor of the dental assistants even surpassing the ethical-legal limits.

Experiência de cárie e situaçäo de higiene oral em crianças dos orfanatos de Anápolis-GO / Caries experience and oral hygiene status among institutionalized children in Anápolis-GO, Brazil

O objetivo do presente estudo foi avaliar a condiçäo de saúde bucal das crianças mantidas nos orfanatos de Anápolis-GO. A populaçäo de estudo foi constituída de 168 crianças de ambos os sexos, na idade de 6 a 12 anos. A prevalência de cárie foi bastante elevada em todas as idades e apenas 5,3 por cento das crianças apresentaram-se livres de cárie. Aos 12 anos, o CPO-D foi 6,37. As necessidades de tratamento na dentiçäo decídua e permanente foram superiores às necessidades atendidas. A situaçäo de higiene oral (IHOS) mostrou-se deficiente para todas as idades. Conclui-se que o estado de saúde bucal deste grupo de crianças é precário e que há necessidade urgente de medidas de promoçäo de saúde bucal nas instituiçöes pesquisadas