ABSTRACT Introduction: Class II division 1 malocclusion treatment with functional devices offers acceptable results. These devices can be removable or fixed, and the essential difference between them is the need for compliance. It is clinically important to investigate if there are differences in the treatment effects of these devices that present different characteristics. Objective: This retrospective longitudinal study compared the treatment effects of Class II correction with the MARA appliance, Activator-Headgear (AcHg) combination, both followed by multibracket fixed appliances, and an untreated control group. Material and Methods: Each experimental group was composed of 18 patients, with a baseline mean age of 11.70 and 10.88 years, treated for 3.60 and 3.17 years. The control group consisted of 20 subjects with baseline mean age of 11.07 years. The groups were evaluated before (T1) and after (T2) treatment. Lateral radiographs were used to evaluate the treatment changes with treatment (T2-T1), compared to the control group. Intergroup comparisons were performed using repeated-measures analysis of variance (ANOVA), followed by Tukey’s test. Results: The AcHg group showed significantly greater maxillary growth restriction than the MARA, while the mandibular changes were due to natural growth. Both devices promoted significantly greater maxillary incisors retrusion, mandibular incisors labial inclination, and improvement of overjet and molar relationships, compared to the control. Conclusions: Both functional devices followed by multibracket appliances were effective to correct Class II malocclusion. Nonetheless, the AcHg combination presents superior skeletal effects, due to significantly greater maxillary growth restriction compared to the MARA appliance. Moreover, the appliances presented similar dentoalveolar effects.

RESUMO Introdução: O tratamento da má oclusão de Classe II divisão 1 com dispositivos funcionais oferece resultados aceitáveis. Esses dispositivos podem ser removíveis ou fixos, e a diferença essencial entre eles é a necessidade de colaboração. É clinicamente importante investigar se existem diferenças nos efeitos do tratamento desses dispositivos que apresentam características diferentes. Objetivo: O presente estudo retrospectivo longitudinal comparou os efeitos do MARA e da combinação Aparelho Extrabucal-Ativador (AEB-At) no tratamento da Classe II, ambos seguidos por aparelho fixo, adicionando também um grupo controle não tratado. Métodos: Cada grupo experimental foi composto por 18 pacientes; respectivamente, com média de idade inicial de 11,70 e 10,88 anos, tratados por 3,60 e 3,17 anos. O grupo controle foi composto por 20 indivíduos, com idade média inicial de 11,07 anos. Os grupos foram avaliados antes (T1) e após (T2) o tratamento. Radiografias de perfil foram utilizadas para avaliar as alterações do tratamento (T2-T1), em comparação com o grupo controle. As comparações intergrupos foram realizadas por meio da análise de variância para medidas repetidas (ANOVA), seguida pelo teste de Tukey. Resultados: O AEB-At apresentou uma restrição do crescimento maxilar significativamente maior que o MARA, enquanto as alterações mandibulares foram decorrentes do crescimento natural. Ambos os dispositivos promoveram significativamente mais retrusão dos incisivos superiores, inclinação vestibular dos incisivos inferiores e melhora da sobressaliência e relação molar, em comparação com o controle. Conclusões: Ambos os dispositivos funcionais associados ao aparelho fixo foram efetivos na correção da má oclusão de Classe II. No entanto, a combinação AEB-At apresenta efeitos esqueléticos superiores, devido à restrição de crescimento maxilar significativamente maior do que com o aparelho MARA. Além disso, os aparelhos apresentaram efeitos dentoalveolares semelhantes.

Abstract Objective Maxillary molar distalization with intraoral distalizer appliances is a non-extraction orthodontic treatment used to correct molar relationship in patients with Class II malocclusion presenting maxillary dentoalveolar protrusion and minor skeletal discrepancies. This study compares the changes caused by three distalizers with different force systems. Methodology 71 patients, divided into three groups, were included. The Jones jig group (JJG, n=30; 16 male, 14 female, 13.17 years mean age) was treated with the Jones jig for 0.8 years. The Distal jet group (DJG, n=25; 8 male, 17 female, 12.57 years mean age) was treated with the Distal jet for 1.06 years. The First Class group (FCG, n=16; 6 male, 10 female, 12.84 years mean age) was treated with the First Class for 0.69 years. Intergroup treatment changes were compared using one-way ANOVA, followed by post-hoc Tukey’s tests. Results Intergroup comparisons showed significantly greater maxillary incisor protrusion in DJG than in FCG (2.56±2.24 mm vs. 0.74±1.39mm, p=0.015). The maxillary first premolars showed progressive and significantly smaller mesial angulation in JJG, FCG and DJG, respectively (14.65±6.31º, 8.43±3.99º, 0.97±3.16º; p<0.001). They also showed greater mesialization in JJG than FCG (3.76±1.46 mm vs. 2.27±1.47 mm, p=0.010), and greater extrusion in DJG compared to JJG (0.90±0.77 mm vs 0.11±0.60 mm, p=0.004). The maxillary second premolars showed progressive and significantly smaller mesial angulation and mesialization in JJG, FCG and DJG, respectively (12.77±5.78º, 3.20±3.94º, -2.12±3.71º and 3.87±1.34 mm, 2.25±1.40 mm, 1.24±1.26 mm, respectively; p<0.001). DJG showed smaller distal angulation of maxillary first molars (-2.14±5.09º vs. -7.73±4.28º and -6.05±3.76º, for the JJG and FCG, respectively; p<0.001) and greater maxillary second molars extrusion (1.17±1.41 mm vs -0.02±1.16 mm and 0.16±1.40 mm, for the JJG and FCG, respectively; p=0.003). Overjet change was significantly larger in DJG compared to FCG (1.79±1.67 mm vs 0.68±0.84; p=0.046). Treatment time was smaller in FCG (0.69±0.22 years vs 0.81±0.33 years and 1.06±0.42 years, comparing it with the JJG and DJG, respectively; p=0.005). Conclusion The three appliances corrected the Class II molar relationship by dentoalveolar changes. The Distal jet produced smaller molar distal angulation than the Jones jig and First Class. The First Class appliance showed less anchorage loss, greater percentage of distalization and shorter treatment time than the Jones jig and Distal jet.

RESUMO Objetivo: o objetivo do presente estudo foi comparar as alterações dentoesqueléticas em pacientes com má oclusão de Classe II, divisão 1, tratados com três tipos de aparelhos funcionais fixos. Métodos: a amostra compreendeu 95 pacientes, selecionados retrospectivamente e divididos em quatro grupos: G1, composto por 25 pacientes (idade média de 12,77 ± 1,24 anos), tratados com aparelho Jasper Jumper; G2, com 25 pacientes (idade média de 12,58 ± 1,65 anos), tratados com aparelho Herbst; G3, com 23 pacientes (idade média de 12,37 ± 1,72 anos), tratados com o Aparelho de Protração Mandibular (APM); e um Grupo Controle (GC), composto por 22 sujeitos não tratados (idade média de 12,66 ± 1,12 anos) que apresentavam a mesma má oclusão. A comparação intergrupos foi realizada com ANOVA, seguida do teste Tukey. Resultados: os grupos Jasper Jumper e Herbst apresentaram significativamente maior restrição de deslocamento anterior da maxila. O Jasper Jumper demonstrou aumento significativamente maior no ângulo do plano mandibular, em comparação ao grupo controle. O grupo APM demonstrou inclinação palatina significativamente maior dos incisivos superiores. O desenvolvimento vertical dos molares superiores foi significativamente maior no grupo Herbst. Conclusões: apesar de algumas diferenças intergrupos na quantidade de alterações dentoesqueléticas, os aparelhos foram eficazes na correção das principais características das más oclusões de Classe II.

ABSTRACT Objective: This study aimed at comparing the dentoskeletal changes in patients with Class II division 1 malocclusion, treated with three types of fixed functional appliances. Methods: A sample comprising 95 patients with the same malocclusion, retrospectively selected, and divided into four groups, was used: G1 consisted of 25 patients (mean age 12.77 ± 1.24 years) treated with Jasper Jumper appliance; G2, with 25 patients (mean age 12.58 ± 1.65 years) treated with the Herbst appliance; G3, with 23 patients (mean age 12.37 ± 1.72 years) treated with the Mandibular Protraction Appliance (MPA); and a Control Group (CG) comprised of 22 untreated subjects (mean age 12.66 ± 1.12 years). Intergroup comparison was performed with ANOVA, followed by Tukey test. Results: The Jasper Jumper and the Herbst group showed significantly greater maxillary anterior displacement restriction. The Jasper Jumper demonstrated significantly greater increase in the mandibular plane angle, as compared to the control group. The MPA group demonstrated significantly greater palatal inclination of the maxillary incisors. Vertical development of the maxillary molars was significantly greater in the Herbst group. Conclusions: Despite some intergroup differences in the amount of dentoskeletal changes, the appliances were effective in correcting the main features of Class II malocclusions.

Resumo Objetivo: o objetivo desse estudo foi comparar as alterações cefalométricas em pacientes com má oclusão de Classe II, divisão 1, tratados com o aparelho Jones Jig ou com extrações dos primeiros pré-molares superiores. Métodos: a amostra consistiu de 88 telerradiografias laterais de 44 pacientes, que foram divididos em dois grupos. O Grupo 1 consistiu de 21 pacientes tratados com o aparelho Jones Jig, com idade inicial média de 12,88 ± 1,23 anos e idade final média de 17,18 ± 1,37 anos, com tempo médio de tratamento de 4,29 anos. O Grupo 2 compreendeu 23 pacientes tratados com extrações dos primeiros pré-molares superiores, com idade inicial média de 13,59 ± 1,91 anos, idade final média de 16,39 ± 1,97 anos, e tempo médio de tratamento de 2,8 anos. A comparação intergrupos das alterações dos tratamentos foi realizada pelos testes t e de Mann-Whitney. Resultados: a correção da Classe II no G2 (extrações dos primeiros pré-molares superiores) apresentou uma retrusão maxilar significativamente maior, redução da discrepância anteroposterior das bases apicais, menor aumento da altura facial anteroinferior e uma redução significativamente maior do trespasse horizontal do que no G1 (aparelho Jones Jig). Conclusões: o tratamento com extrações dos primeiros pré-molares superiores promoveu maior redução do trespasse horizontal, mas os dois protocolos de tratamento produziram alterações semelhantes no perfil tegumentar.

Abstract Objective: The aim of this study was to compare the cephalometric changes in Class II division 1 malocclusion patients treated with Jones Jig appliance or with maxillary first premolar extractions. Methods: The sample consisted of 88 lateral cephalograms of 44 patients, divided into two groups. Group 1 consisted of 21 patients treated with Jones Jig appliance, with a mean initial age of 12.88 ± 1.23 years and final mean age of 17.18 ± 1.37 years, and a mean treatment time of 4.29 years. Group 2 comprised 23 patients treated with maxillary first premolar extractions, with a mean initial age of 13.59 ± 1.91 years and mean final age of 16.39 ± 1.97 years, and a mean treatment time of 2.8 years. Intergroup treatment changes were compared with t and Mann-Whitney tests. Results: Class II correction in G2 (maxillary first premolar extractions) presented significantly greater maxillary retrusion, reduction of anteroposterior apical base discrepancy, smaller increase in the lower anterior face height and significantly greater overjet reduction than G1 (Jones Jig). Conclusions: Treatment with maxillary first premolar extractions produced greater overjet reduction, but the two treatment protocols produced similar changes in the soft tissue profile.

Abstract The aim of this study was to assess, correlate, and compare users’ perceptions and preference related to maxillary removable retainers. Volunteers were recruited to use four retainer types: conventional wrap-around (CWA), wrap-around with an anterior opening (OWA), “U” wrap-around (UWA), and clear thermoplastic retainer (CT). The main outcomes were the volunteers’ perceptions, evaluated with a 100-mm visual analogue scale, and their preferred retainer. The retainers were used for 21 days each (washout intervals of 7 days). Nineteen volunteers (27 ± 4.53 years) were randomly divided into four groups that used the four retainers, but with a different sequence. Perceptions were evaluated immediately after the use of each retainer and the preference at the end of the research. Repeated measures ANOVA and Friedman tests with post-hoc Tukey’s test (intergroup comparisons), and Pearson and Spearman analyses (correlations between perceptions) were applied. The WA retainers did not significantly differ among themselves. The CT was rated significantly worse in speech (p ≤ 0.001), discomfort (p < 0.001), and occlusal interference (p < 0.001), and did not significantly differ from the others in esthetics. Users preferred significant more the WA retainers in comparison with the CT retainers. The occlusal interference caused by the CT was positively correlated to other perceptions, such as changes in speech and discomfort. WA retainers presented similar preference and perceptions, but were significantly better than the CT. The CT occlusal coverage appeared to be the primary cause of its rejection.

Resumo Introdução Este estudo transversal buscou associar resultados cefalométricos normativos do tratamento do retrognatismo mandibular com melhora estética do perfil facial na percepção do paciente. Objetivo este estudo transversal buscou associar resultados cefalométricos normativos do tratamento do retrognatismo mandibular com melhora estética do perfil facial na percepção do paciente. Material e método Os resultados cefalométricos normativos obtidos em radiografias cefalométricas laterais de uma amostra de 24 pacientes com maloclusão de Classe II em fase de crescimento tratados com aparelho de avanço mandibular, foram avaliados comparando-se as grandezas pré e pós-tratamento. As mesmas radiografias foram utilizadas para gerar silhuetas negras padronizadas que foram dispostas aleatoriamente. Os pacientes foram instruídos a escolher seu perfil preferido e indicar quanta mudança foi percebida por meio de uma escala de Likert de 7 pontos. Os dados foram comparados com resultados cefalométricos aplicando-se metodologia de modelos mistos para medidas repetidas no tempo, teste t de student e teste t para variâncias heterogêneas, com nível de significância de 5%. Resultado 75% dos pacientes escolheram silhuetas pós-tratamento e a mudança foi percebida independentemente da escolha por pré ou pós-tratamento. Não houve diferença significativa entre as variáveis cefalométricas dos traçados que deram origem às silhuetas consideradas melhores e piores após a avaliação. Conclusão Não houve associação entre os resultados cefalométricos pós-tratamento e a percepção da melhora estética por pacientes ortodônticos.

Abstract Introduction This cross-sectional study aimed to associate the normative cephalometric results of mandibular retrognathism treatment with patient perception on the esthetic improvement of facial profile. Objective this cross-sectional study aimed to associate the normative cephalometric results of mandibular retrognathism treatment with patient perception on the esthetic improvement of facial profile. Material and method The normative cephalometric results were obtained from lateral cephalometric radiographs of a sample of 24 Class II malocclusion patients in the pubertal growth spurt. Such patients were treated with a mandibular advancement device and evaluated by comparing pre- and post-treatment variables. The same radiographs were used to produce standardized black silhouettes that were randomly arranged. Patients were instructed to choose their preferred profile and indicate the changes perceived using a 7-point Likert scale. The data were compared with cephalometric results using a mixed-model methodology for time-repeated measures, Student’s t-test, and t-test for heterogeneous variances, at 5% significance level. Result A rate of 75% of patients preferred post-treatment silhouettes and changes were perceived regardless of the choice of either pre- or post-treatment profile. There was no significant difference between the cephalometric variables of the tracings that produced the silhouettes considered better or worse after the evaluation. Conclusion There was no association between the cephalometric results after treatment and the perception of esthetic improvement by patients treated for mandibular retrognathia.

RESUMO Objetivo: o objetivo do presente estudo foi comparar os efeitos esqueléticos, dentários e em tecidos moles do Aparelho de Protração Mandibular (APM) em pacientes adolescentes e adultos com má oclusão de Classe II. Métodos: a amostra consistiu das telerradiografias pré- e pós-tratamento de 39 indivíduos com má oclusão de Classe II tratados com APM e aparelhos fixos. A amostra foi dividida em dois grupos: o Grupo 1 compreendeu 23 indivíduos (10 homens e 13 mulheres), com idade inicial de 11,75 anos, com um tempo médio de tratamento de 3,32 anos; o Grupo 2 incluiu 16 pacientes (7 do sexo masculino e 9 do sexo feminino), com idade média inicial de 22,41 anos, com um tempo médio de tratamento de 4,24 anos. A comparação intergrupos dos estágios inicial e final e das alterações com o tratamento foi realizada com testes t, considerando-se um nível de significância de p< 0,05. Resultados: os adultos apresentaram quantidades menos significativas de alterações esqueléticas, dentoalveolares e de tecidos moles do que os adolescentes. Houve uma inclinação palatina significativamente maior dos incisivos superiores e retrusão do lábio superior nos adolescentes. O grupo de adultos apresentou maior proclinação dos incisivos inferiores no estágio pós-tratamento. Conclusão: pacientes adultos tratados com APM apresentaram quantidades menos significativas de alterações esqueléticas, dentoalveolares e de tecidos moles do que os adolescentes.

ABSTRACT Objective: The aim of this study was to compare the skeletal, dental, and soft tissue effects of the Mandibular Protraction Appliance (MPA) application in adolescent and adult Class II malocclusion patients. Methods: The sample comprised the pretreatment and posttreatment lateral cephalograms of 39 subjects presenting Class II malocclusion treated with the MPA and fixed appliances. Sample was divided into two groups: Group 1 comprised 23 subjects (10 male; 13 female), at a mean pretreatment age of 11.75 years, with a mean treatment time of 3.32 years; Group 2 included 16 subjects (7 male; 9 female), at a mean pretreatment age of 22.41 years, with a mean treatment time of 4.24 years. Intergroup comparison of the initial and final stages and treatment changes between the groups was performed with t tests, at p< 0.05. Results: The adults showed less significant amounts of skeletal, dentoalveolar and soft tissue changes than the adolescents. There was significantly greater palatal tipping of the maxillary incisors and retrusion of the upper lip in the adolescents. The adult group showed greater mandibular incisor proclination in the posttreatment stage. Conclusion: Adult patients treated with MPA showed less significant amounts of skeletal, dentoalveolar and soft tissue changes than adolescents.

Resumo Objetivo Este estudo analisou as alterações dentárias, esqueléticas e tegumentares promovidas pelo Aparelho de Protração Mandibular (APM) por meio da análise de Ricketts. Material e método A amostra contou com 27 pacientes (14 meninas e 13 meninos) com má oclusão de Classe II, perfil facial convexo, trespasse horizontal aumentado e deficiência mandibular, com idade média inicial de 12,27 e final de 15,18 anos, tratados com aparelho fixo combinado com o APM. A comparação das telerradiografias iniciais (T1) e finais (T2) foi realizada pelo teste t dependente, com nível de significância de 5%. Resultado Observou-se diferença estatisticamente significante para a retrusão (p=0.000) e lingualização dos incisivos superiores (p=0.000), protrusão (p=0.000) e vestibularização dos incisivos inferiores (p=0.000), aumento do ângulo interincisivos (p=0.002), melhora da relação molar (p=0.003), restrição do deslocamento anterior da maxila (p=0.000), diminuição do ângulo do plano mandibular (p=0.024) e melhora do perfil facial (p=0.000). Conclusão O APM promoveu alterações dentoalveolares, observadas principalmente pela diminuição do ângulo do plano mandibular e restrição do deslocamento para anterior da maxila que contribuíram para a melhora do perfil do paciente.

Abstract Objective This study was designed to evaluate the skeletal, dental and soft tissue effects of mandibular deficiency treatment with the mandibular protraction appliance (MPA) using 12 factors of the Ricketts analysis. Material and method This cross-sectional retrospective study sample consisted of a group (n = 27), with Class II malocclusion, convex facial profile, increased horizontal trespass and mandibular deficiency, with initial mean age of 12.27 and final of 15.18 years, treated with fixed appliance combined with the MPA, in an average time of 2.9 years. Initial and final radiographs were investigated using Ricketts analysis. The dependent t-test was used to compare the initial and final phases of the MPA group, with a significance level of 5%. Result Statistically significant differences were observed for dental changes such as retrusion (p=0.000) and palatal inclination of the maxillary incisors (p=0.000); protrusion (p=0.000) and buccal inclination of the mandibular incisors (p=0.000); increased interincisal angle (p=0.002) and improved molar ratio (p=0.003). There was also a restriction of the anterior displacement of the maxilla (p=0.000) and a decrease in the mandibular plane angle (p=0.024). The variable inferior labial protrusion with significance (p=0.000), reiterated the improvement in the profile. Conclusion The effects of MPA on correction of malocclusion Class II, verified by Ricketts analysis occurred predominantly by dentoalveolar changes, decrease in the Mandibular Plane Angle, and restriction of anterior displacement of the maxilla, which contributed to the improvement in the patient's profile.

RESUMO INTRODUÇÃO: a análise facial subjetiva é um método diagnóstico que privilegia a avaliação morfológica da face; assim, o principal objetivo do presente trabalho foi comparar os diagnósticos faciais e dentários e investigar a correlação entre eles. MÉTODOS: a amostra consistiu de 151 crianças (7 a 13 anos de idade), sem nenhum tratamento ortodôntico prévio, analisadas por um ortodontista. Foram realizadas fotografias padronizadas extrabucais e intrabucais, para a classificação subjetiva dos Padrões Faciais e das relações dentárias segundo a classificação de Angle. Investigou-se a ocorrência de diferentes tipos de Padrões Faciais, em vistas frontal e de perfil; a relação entre os Padrões Faciais e as relações dentárias de Classe e, também, entre a má oclusão de mordida aberta anterior e o Padrão Face Longa. RESULTADOS: o Padrão Facial I (PF I) esteve presente em 64,24% das crianças; o PF II, em 21,29%; o PF III, em 6,62%; o PF Face Longa, em 5,96% e o PF Face Curta, em 1,99%. Observou-se concordância substancial entre a avaliação do PF na vista frontal e na de perfil, igual a 84% (Kappa = 0,69). Houve concordância entre a avaliação da relação dentária de Classe e do PF em 63% da amostra (Kappa = 0,27). O PF Face Longa não demonstrou maior prevalência da má oclusão de mordida aberta. CONCLUSÃO: os Padrões Faciais I e II foram os mais prevalentes em crianças, enquanto o menos prevalente foi o Padrão Face Curta. Verificou-se concordância significativa entre as análises faciais frontal e de perfil. Existe uma ligeira concordância entre o Padrão Facial e a relação sagital dentária. A mordida aberta anterior não se apresentou mais prevalente em nenhum tipo de Padrão Facial.

ABSTRACT INTRODUCTION: Subjective facial analysis is a diagnostic method that provides morphological analysis of the face. Thus, the aim of the present study was to compare the facial and dental diagnoses and investigate their relationship. METHODS: This sample consisted of 151 children (7 to 13 years old), without previous orthodontic treatment, analyzed by an orthodontist. Standardized extraoral and intraoral photographs were taken for the subjective facial classification according to Facial Pattern classification and occlusal analyses. It has been researched the occurrence of different Facial Patterns, the relationship between Facial Pattern classification in frontal and profile views, the relationship between Facial Patterns and Angle classification, and between anterior open bite and Long Face Pattern. RESULTS: Facial Pattern I was verified in 64.24% of the children, Pattern II in 21.29%, Pattern III in 6.62%, Long Face Pattern in 5.96% and Short Face Pattern in 1.99%. A substantial strength of agreement of approximately 84% between frontal and profile classification of Facial Pattern was observed (Kappa = 0.69). Agreement between the Angle classification and the Facial Pattern was seen in approximately 63% of the cases (Kappa = 0.27). Long Face Pattern did not present more open bite prevalence. CONCLUSION: Facial Patterns I and II were the most prevalent in children and the less prevalent was the Short Face Pattern. A significant concordance was observed between profile and frontal subjective facial analysis. There was slight concordance between the Facial Pattern and the sagittal dental relationships. The anterior open bite (AOB) was not significantly prevalent in any Facial Pattern.

Abstract The aim of this study was to evaluate deflection forces of orthodontic wires of different alloys engaged into conventional brackets using several ligation types. Stainless steel, conventional superelastic nickel-titanium and thermally activated nickel-titanium archwires tied into conventional brackets by a ring-shaped elastomeric ligature (RSEL), a 8-shaped elastomeric ligature (8SEL) and a metal ligature (ML) were tested. A clinical simulation device was created especially for this study and forces were measured with an Instron Universal Testing Machine. For the testing procedure, the block representing the maxillary right central incisor was moved 0.5 and 1 mm bucco-lingually at a constant speed of 2 mm/min, and the forces released by the wires were recorded, in accordance with the ISO 15841 guidelines. In general, the RSEL showed lighter forces, while 8SEL and ML showed higher values. At the 0.5 mm deflection, the 8SEL presented the greatest force, but at the 1.0 mm deflection the ML had a statistically similar force. Based on our evaluations, to obtain lighter forces, the thermally activated nickel-titanium wire with the RSEL are recommended, while the steel wire with the 8SEL or the ML are recommended when larger forces are desired. The ML exhibited the highest force increase with increased deflections, compared with the elastomeric ligatures.

RESUMO Objetivo: o objetivo deste estudo foi avaliar as forças de deflexão de fios ortodônticos retangulares em braquetes convencionais (MorelliTM) e autoligáveis ativos (In-Ovation RTM ) e passivos (Damon 3MXTM). Material e Métodos: foram utilizadas duas marcas comerciais (MorelliTM e GACTM) de fios de aço inoxidável e de níquel-titânio (NiTi), além do fio de NiTi com adição de cobre (OrmcoTM). Os espécimes foram montados em um dispositivo de simulação clínica especialmente desenhado para esse estudo e testado em uma máquina universal de ensaios Instron. Para o procedimento dos testes, a peça representativa do incisivo central superior direito foi movida no sentido vestibulolingual em ativações de 0 a 1 mm, com leituras da força liberada pela deflexão em 0,5; 0,8 e 1 mm, em uma velocidade constante de 2 mm/min. As forças interbraquetes com os fios de aço, de NiTi e NiTi com adição de cobre foram individualmente comparadas pelo teste de ANOVA a dois critérios, seguido pelo teste de Tukey. Resultados: houve menor liberação de forças nos braquetes convencionais, seguidos pelos braquetes autoligáveis ativos e passivos. Entre as marcas comerciais, somente houve diferença para o fio de NiTi, onde a marca MorelliTM apresentou maiores forças do que a GACTM. Conclusão: os braquetes promovem diferentes graus de forças de deflexão, sendo que os braquetes autoligáveis liberam as maiores forças.

ABSTRACT Introduction: The aim of the study was to evaluate deflection forces of rectangular orthodontic wires in conventional (MorelliTM), active (In-Ovation RTM) and passive (Damon 3MXTM) self-ligating brackets. Material and Methods: Two brands of stainless steel and nickel-titanium (NiTi) wires (MorelliTM and GACTM), in addition to OrmcoTM copper-nickel-titanium wires were used. Specimens were assembled in a clinical simulation device especially designed for this study and tested in an Instron universal testing machine. For the testing procedures, an acrylic structure representative of the maxillary right central incisor was lingually moved in activations of 0 to 1 mm, with readings of the force released by deflection in unloading of 0.5, 0.8 and 1 mm at a constant speed of 2 mm/min. Inter-bracket forces with stainless steel, NiTi and CuNiTi were individually compared by two-way ANOVA, followed by Tukey’s tests. Results: Results showed that there were lower forces in conventional brackets, followed by active and passive self-ligating brackets. Within the brands, only for NiTi wires, the MorelliTM brand presented higher forces than GACTM wires. Conclusions: Bracket systems provide different degrees of deflection force, with self-ligating brackets showing the highest forces.

ABSTRACT Objective: The purpose of this study was to evaluate the deflection forces of Nitinol orthodontic wires placed in different types of brackets: metallic, reinforced polycarbonate with metallic slots, sapphire, passive and active self-ligating, by assessing strength values variation according to gradual increase in wire diameter and deflection and comparing different combinations in the different deflections. Material and Methods: Specimens were set in a clinical simulation model and evaluated in a Universal Testing Machine (INSTRON 3342), using the ISO 15841 protocol. Data were subjected to One-way ANOVA, followed by Tukey tests (p<0.05). Results: Self-ligating brackets presented the most similar behavior to each other. For conventional brackets there was no consistent behavior for any of the deflections studied. Conclusions: Self-ligating brackets presented the most consistent and predictable results while conventional brackets, as esthetic brackets, showed very different patterns of forces. Self-ligating brackets showed higher strength in all deflections when compared with the others, in 0.020-inch wires.

Objetivo: avaliar a estabilidade da inclinação mesiodistal dos molares superiores cinco anos após o tratamento realizado com o aparelho Pendulum seguido de aparelho ortodôntico fixo. As mudanças na angulação foram comparadas com uma amostra não tratada. Métodos: a amostra consistiu de 20 pacientes (14 do sexo feminino e 6 do masculino) com má oclusão de Classe II, divisão 1 tratados por meio da distalização dos molares com o aparelho Pendulum seguido de ancoragem extrabucal cervical e aparelho fixo. A inclinação dos molares superiores foi avaliada por meio de radiografias panorâmicas. A média da idade ao início do tratamento foi de 14,3 ± 1,6 anos; ao final do tratamento, de 18,6 ± 1,8 anos e, no longo tempo pós-tratamento, de 23,8 ± 2,0 anos. Para comparação, foi usado um grupo controle com 16 indivíduos não tratados e com oclusão normal, apresentando idades entre 12 e 17 anos. Os dados foram analisados estatisticamente pelo teste t independente e ANOVA, seguido do teste de Tukey. Resultados: os primeiros molares superiores apresentaram diferenças estatisticamente significativas entre T1 (94,5o) e T2 (98,8o), bem como entre T2 e T3 (94,7o). Os segundos molares superiores não apresentaram alterações estatisticamente significativas no seu posicionamento durante os períodos avaliados, T1 (107,5o), T2 (109,3o) e T3 (106,9o). Conclusões: apesar de os primeiros molares superiores apresentarem inclinação distal da coroa imediatamente após o tratamento, aproximadamente cinco anos depois suas raízes tendem a ocupar posições próximas às do início do tratamento.

Objective: To evaluate the stability of mesiodistal inclination of maxillary molars produced by a pendulum appliance, five years after completion of orthodontic treatment. Angulation changes were compared to an untreated sample. Methods: The sample consisted of 20 patients (14 females and 6 males) with Class II, Division 1 malocclusion that was treated through molar distalization with a pendulum appliance followed by cervical headgear and full fixed appliances. Maxillary molar inclination was evaluated through panoramic radiograph. The mean age at pretreatment was 14.3 ± 1.6 years, whereas at immediate post-treatment it was 18.6 ± 1.8 years, and at long-term post-treatment it was 23.8 ± 2.0 years. A control group of 16 untreated individuals with untreated normocclusion ranging in age from 12 to 17 years old were used as comparison group. Data were statistically analyzed with independent t-tests and ANOVA test followed by Tukey post-hoc tests. Results: Statistically significant differences were found between T1 (94.50) and T2 (98.80) as well as between T2 and T3 (94.70) for maxillary first molars. Maxillary second molars did not show any statistically significant positional changes during the evaluated time periods T1 (107.50), T2 (109.30) and T3 (106.90). Conclusion: Although maxillary first molars underwent distal crown inclination immediately after treatment, approximately five years thereafter their roots tended to upright close to the pretreatment positions.

OBJECTIVE: The purpose of this study was to determine the accuracy and reliability of two methods of measurements of linear distances (multiplanar 2D and tridimensional reconstruction 3D) obtained from cone-beam computed tomography (CBCT) with different voxel sizes. MATERIAL AND METHODS: Ten dry human mandibles were scanned at voxel sizes of 0.2 and 0.4 mm. Craniometric anatomical landmarks were identified twice by two independent operators on the multiplanar reconstructed and on volume rendering images that were generated by the software Dolphin®. Subsequently, physical measurements were performed using a digital caliper. Analysis of variance (ANOVA), intraclass correlation coefficient (ICC) and Bland-Altman were used for evaluating accuracy and reliability (p<0.05). RESULTS: Excellent intraobserver reliability and good to high precision interobserver reliability values were found for linear measurements from CBCT 3D and multiplanar images. Measurements performed on multiplanar reconstructed images were more accurate than measurements in volume rendering compared with the gold standard. No statistically significant difference was found between voxel protocols, independently of the measurement method. CONCLUSIONS: Linear measurements on multiplanar images of 0.2 and 0.4 voxel are reliable and accurate when compared with direct caliper measurements. Caution should be taken in the volume rendering measurements, because the measurements were reliable, but not accurate for all variables. An increased voxel resolution did not result in greater accuracy of mandible measurements and would potentially provide increased patient radiation exposure.

OBJETIVO: as características cefalométricas dentárias variam consideravelmente entre as diferentes raças. No Brasil, em virtude da grande miscigenação populacional, é necessário conhecer, também, as variações apresentadas pelas misturas dessas raças. Por essa razão, o objetivo desse estudo foi identificar o padrão das variáveis dentárias de jovens mestiços nipo-brasileiros com oclusão normal e compará-los com amostras semelhantes de leucodermas e de xantodermas. MÉTODOS: foram utilizadas 40 telerradiografias de jovens leucodermas, 32 de nipo-brasileiros e 33 de xantodermas. As rês amostras apresentavam indivíduos com oclusão normal e face bem balanceada. Foram realizadas análises estatísticas de variância a um critério (ANOVA) e a de covariância (ANCOVA). Basicamente, as variáveis cefalométricas usadas seguiram as preconizadas por Steiner, Tweed e McNamara Jr. RESULTADOS: encontrou-se diferença estatística (p < 0,05) entre as raças em cinco das variáveis estudadas. Essas diferenças indicaram menor ângulo interincisivos e menor sobremordida para a amostra nipo-brasileira, com relação à amostra leucoderma, mas com valores semelhantes aos da amostra xantoderma. CONCLUSÃO: os valores dentários encontrados para os jovens nipo-brasileiros foram, em geral, mais similares àqueles da amostra de xantoderma.

INTRODUCTION: The objective of this study was to identify the patterns of dental variables of adolescent Japanese-Brazilian descents with normal occlusion, and also to compare them with a similar Caucasian and Mongoloid sample. METHODS: Lateral cephalometric radiographs were used to compare the groups: Caucasian (n = 40), Japanese-Brazilian (n = 32) and Mongoloid (n = 33). The statistical tests used were one-way ANOVA and ANCOVA. The cephalometric measurements used followed the analyses of Steiner, Tweed and McNamara Jr. RESULTS: Statistical differences (P < 0.05) indicated a smaller interincisal angle and overbite for the Japanese-Brazilian sample, when compared to the Caucasian sample, although with similar values to the Mongoloid group. CONCLUSION: The dental patterns found for the Japanese-Brazilian descents were, in general, more similar to those of the Mongoloid sample.