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OBJECTIVE: To assess volume and surface of the mandibular condyle on cone beam computed tomography (CBCT) scans by comparing Class I, II, and III malocclusions. METHODS: CBCT scans of 55 patients were assessed to measure ANB angle, condyle volume, and surface by using VistaDent software. The values were compared between the different skeletal malocclusions and correlated to gender and sides. Kruskal-Wallis test was used for comparison of malocclusions and Mann-Whitney test and Wilcoxon test for comparisons of genders and sides. Statistical significance was defined as p < 0.05. RESULTS: There were no significant differences in volume (p = 0.588) and surface (p = 0.830) between the malocclusion classes. The comparison between sides showed a statistically significant difference for surface (p = 0.038). CONCLUSION: Condylar volume and surface evaluated on CBCT scans showed no statistically different values for Class I, II, and III malocclusions.

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Resumo O número de pacientes adultos que buscam o tratamento ortodôntico tem aumentado e essa mudança no cenário da Ortodontia tem exigido dos profissionais o emprego de aparelhos estéticos que proporcionem a correção das más oclusões por meio de abordagens simplificadas, eficientes e de maior conforto. Assim sendo, este artigo tem como objetivo apresentar uma técnica alternativa que pode ser empregada pelos profissionais na correção de más oclusões simples e na resolução de recidivas de apinhamento dentário na região anterior do arco. O artigo descreve a confecção passo a passo do sistema Aligner Tubes que é constituído por tubos metálicos colados às faces vestibulares dos elementos dentários anteriores e na sequência ilustra a aplicabilidade desse método com a exemplificação de relato de um caso clínico. Conclui-se que é um sistema simplificado, estético e de baixo custo que possibilita a correção dos problemas simples, em tempo relativamente curto e com resultados satisfatórios.(AU)

Abstract The number of adult patients searching for orthodontic treatment has increased and this change in the Orthodontic routine has required from professionals the use of aesthetic devices that provide malocclusions correction through simplified, efficient, and more comfortable approaches. Therefore, this article aims to present an alternative technique that can be used by professionals in the correction of minor malocclusions and in the resolution of dental crowding recurrences in the anterior region of the arch. This article describes the step-by-step preparation of the Aligner Tubes system, which consists of metallic tubes bonded to the buccal surfaces of the anterior teeth and then illustrates the applicability of this method with one clinical case report example. It is concluded that it is a simplified, aesthetic, and low cost system that allows the correction of simple problems in a relatively short time and with satisfactory results.(AU)

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The aim of this study was to evaluate and compare changes in linear distance and inclination of lower incisors and canines and intercanine distance after a 30 months orthodontic treatment with self-ligating appliances. Seven patients were treated orthodontically with a Roth prescription passive self-ligating bracket. To perform the measurements and comparisons, CBCT scans were taken before the start of the orthodontic treatment (T1) and after a period of 30 months treatment (T2). The following measurements were performed: (1) the lower incisors and canines inclination in relation to the mandibular plane, (2) intercanine linear distance in millimeters and (3) linear distance in millimeters of the incisal and apical part of lower anterior teeth to a plane (POGM) passing through pogonion point and perpendicular to the mandibular plane. No significant difference were observed between T1 and T2 for canine inclination (p = 0.835), incisors inclination (p = 0.149), canine incisal distance to POGM (p = 0.423) and incisors incisal distance to POGM (p = 0.966), however canine apical distance (p = 0.049) and incisors apical distance (p = 0.002) to POGM was lower at T1 than at T2. The intercanine distance was significantly lower (p = 0.022) at T1 when compared to T2. The use of passive self-ligating brackets in orthodontic treatment to solve 4 mm tooth crowding were able to produce dental arch expansion by bodily tooth movement.

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OBJECTIVE: This study sought to assess the relationship between the dimensions of the maxillary sinus drainage system with the content of sinuses. DESIGN: Three-hundred cone beam computed tomography images were selected from a database (105 males and 195 females). The images were assessed by a single investigator, trained and calibrated, performing image analysis. The length of the infundibulum and the ostium height in both maxillary sinuses were measured. The data were analyzed using Minitab 16, using 5% as a critical p-value. RESULTS: A significant gender difference was also found for presence in the normal content of sinus for females and presence of antral pseudocyst for males (p < 0.05). Subjects with normal content in the maxillary sinus present lower ostium height values. There were statistically significant with presence of and higher ostium height values and antral pseudocyst (p < 0.01). CONCLUSION: The current study results demonstrated that some sinusopathies were significantly related to dimensions of maxillary sinus drainage.

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BACKGROUND: Clinical cases involving agenesis of all four maxillary incisors are rare, with no previous reports in the literature. CASE REPORT: The present case report describes an orthodontic treatment combined with esthetic dentistry in a 10-year-old girl with agenesis of all four permanent maxillary incisors, anterior crossbite, permanence of deciduous maxillary canines and transmigration of permanent maxillary canines into the region of the maxillary central incisors. For this case, it was decided on space closure using a fixed orthodontic apparatus and reshaping of the first premolars transforming them into canines. Porcelain veneers were used on the permanent and deciduous canines, substituting the maxillary central and lateral incisors, respectively. Regarding outcome, there was an improvement in facial profile, correction of the anterior crossbite, satisfactory intercuspidation of the teeth and significant esthetic improvement in smile. Maintaining the patient´s natural dentition also kept the bone plate intact for future placement of implants to substitute maxillary deciduous canines at the appropriate age. CONCLUSIONS: Interdisciplinary planning combining orthodontics and esthetic dentistry was key in resolving this case. Key words:Tooth agenesis, upper incisors, orthodontic treatment.

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OBJECTIVES: This retrospective study aimed to evaluate the dentoalveolar, skeletal, and soft tissue effects obtained with bone-anchored pendulum appliance in patients with Class II malocclusion. MATERIALS AND METHODS: A total of 18 patients (4 male, 14 female) at a mean pretreatment age of 14.0 years (+1.08) were enrolled in this study. All patients were treated with the bone-anchored pendulum appliance for an average duration of 4.8 months. Only the active distalization period was evaluated with predistalization and postdistalization lateral cephalograms. Skeletal, dentoalveolar, and soft tissue variables were obtained. Based on these variables, the treatment effects were evaluated with dependent t-test. RESULTS: Correction of Class II molar relationship resulted from distal movement of 3.45 mm and tipping of 11.24° of the first maxillary molars. The premolars were distalized accompanying the molars. CONCLUSIONS: The bone-anchored pendulum appliance proved to be an effective method for distalization of maxillary molars in cases that require maximum anchorage, avoiding reciprocal mesial movement of premolars and incisors.

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AIMS: The purpose of this study was to evaluate the effect of the corticosteroid therapy for both treatment of juvenile systemic lupus erythematosus and disease activity on two masticatory muscles and condyle of the temporomandibular joint. METHODS: A total of 21 controls and 48 juvenile systemic lupus erythematosus patients were investigated. Volumes of the temporal and masseter muscles and condyle of the subjects were assessed by using a 3D reconstruction in magnetic resonance imaging. The ITK-SNAP, a medical imaging software, was used for 3D reconstruction. A dental examination with registration of occlusion was performed in subjects. Data were statistically analyzed by means of the Dahlberg's test associated with paired t-test, Fisher's exact test and Chi-square. RESULTS: There was a positive correlation between temporalis muscle and age (p = 0.032), masseter volume (p = 0.029) and condyle volume (p = 0.013). The mean volume measurements of temporal and masseter muscles and condyle were not statistically associated with juvenile systemic lupus erythematosus regarding disease activity and corticosteroid therapy (p > 0.05). There were no significant differences between malocclusion and volume of muscles and condyle. CONCLUSION: This study suggested that volume of the target structures has no correlation with cumulative corticosteroid dose, disease activity, and malocclusion.

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PURPOSE: The sphenoid sinus is the most inaccessible part of the face, being inside the sphenoid bone and closely related to numerous vital neural and vascular structures. The objective of this study was to analyze and evaluate the variation of anatomy and the volume of the sphenoid sinus using helical computed tomography and medical imaging software. MATERIALS AND METHODS: A total of 47 helical CT scans of sinuses of male and female individuals aged 18-86 years were selected. The images were formatted using ITK-SNAP software, consisting of three steps: (1) segmentation; (2) volumetric analysis and (3) 3D reconstruction. The sphenoid sinuses were also classified according to Hammer, i.e., in conchal, pre-sellar, sellar and post-sellar types. A single investigator, who is specialist in dental radiology and was trained and calibrated, performed the volume and image analysis. After 15 days, the segmentations were repeated. RESULTS: The Dunn's multiple comparison test revealed significant differences in the volume rankings between the right and left sides (P = 0.0002), with the post-sellar type presenting the greatest volume on the right side compared to pre-sellar and sellar types. In the left sphenoid sinuses, the post-sellar type showed the greatest volume. The Lin's correlation coefficient showed excellent reproducibility values. CONCLUSIONS: According to the applied methodology, it was found that the volume of the sphenoid sinus was influenced by neither age nor gender (P > 0.005). There was difference in the volumes of sphenoid sinus on the right and left sides and in the anatomical classification.

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OBJECTIVE: The present study aimed to evaluate the precision of the torque applied by 0.022" self-ligating brackets of different brands, the precision of parallelism between the inner walls of their slots, and precision of their slot height. Eighty brackets for upper central incisors of eight trademarked models were selected: Abzil, GAC, American Orthodontics, Morelli, Orthometric, Ormco, Forestadent, and Ortho Organizers. Images of the brackets were obtained using a scanning electron microscope (SEM) and these were measured using the AutoCAD 2011 software. The tolerance parameters stated in the ISO 27020 standard were used as references. The results showed that only the Orthometric, Morelli, and Ormco groups showed results inconsistent with the ISO standard. Regarding the parallelism of the internal walls of the slots, most of the models studied had results in line with the ISO prescription, except the Morelli group. In assessing bracket slot height, only the Forestadent, GAC, American Orthodontics, and Ormco groups presented results in accordance with the ISO standard. The GAC, Forestadent, and American Orthodontics groups did not differ in relation to the three factors of the ISO 27020 standard. Great variability of results is observed in relation to all the variables.

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We evaluated lateral pterygoid muscle volume in closed and open mouth positions in association with anterior disc displacement, effusion and abnormal articular disc shape from three-dimensional reformations of MRI. A total of 24 MRI of a sample (15 females, 9 males) aged 19-64 years (37.2 years±11.4) were assessed. Segmentation and volumetric assessment of the total, upper and lower heads of the lateral pterygoid muscle were performed using free software. The upper head of the lateral pterygoid muscle had a smaller volume than the lower head at both sides, in the closed- and open-mouth positions. In the open-mouth position, individuals with a subdivided upper head, where one component was inserted in the articular disc and another in the mandibular head, displayed a significantly larger volume of the upper head compared to individuals who had a single attachment to the articular disc (p=0.0130). The lateral pterygoid muscle has different volumes in the closed- and open-mouth positions. Gender affected muscle volume, specifically the upper head component. Insertion type in the upper head also seemed to affect muscle volume.

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A Ortodontia lingual é, sem dúvida, uma forma de tratamento ortodôntico que se destaca pela sua característica estética. O presente caso clínico visa relatar a correção de uma má-oclusão de classe I com biprotrusão dentária em uma paciente xantoderma de 23 anos e dois meses, utilizando-se a técnica lingual. Os braquetes empregados foram da prescrição PSWb (Prieto Straight Wire bracket) e os aparelhos foram instalados pelo método de transferência guiada por canaletas. O caso foi tratado com a extração dos primeiros pré-molares superiores e inferiores. Imediatamente após a montagem do aparelho, os dentes a serem extraídos foram desgastados nas proximais, para facilitar a eliminação do apinhamento. Sequencialmente às etapas de alinhamento e nivelamento incorporou-se os arcos de aço inoxidável .017" x .025", e foram promovidas as exodontias, adaptados os pônticos estéticos e iniciado o fechamento de espaços com retração dos dentes anteriores. O resultado final mostrou significativa redução da protrusão, intercuspidação satisfatória em neutroclusão e melhora do perfil e do sorriso da paciente, preservando suas características raciais.

Undoubtedly, lingual orthodontics is a highly considered treatment due to its esthetic nature. This article reports the correction of a dental biprotrusion in a twenty-three-year-old xantoderm patient using the lingual technique. The brackets used were the PSWb (Prieto Straight-Wire bracket) which were installed by the groove-guided indirect transfer. The case was treated by extracting the upper and lower first premolars. Immediately after installation, the teeth to be extracted were adjusted in their proximal surfaces to facilitate the elimination of crowding. After aligning and leveling .017" x .025" stainless arches were incorporated, dental extractions were promoted, aesthetic pontics were adapted and space closure with anterior teeth retraction initiated. The final result showed significant reduction of the protrusion; satisfactory intercuspation in Angle class I; improvement of the patient's profile and smile while still preserving her racial characteristics.

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AIM: The purpose of this study was to evaluate the dentoskeletal and soft tissue effects resulting from treatment with Klammt's elastic open activator (EOA) functional orthopedic appliance in patients with Class II malocclusion characterized by mandibular deficiency. MATERIALS AND METHODS: Teleradiographs were evaluated in the lateral aspect of the initial (T1) and final (T2) orthopedic phases for 16 patients with Class II, Division 1 malocclusion. The age range was from 9 to 11.2 years, with a mean age of 9.9 years. The cephalometric points were demarcated, and cephalometric measurements were obtained by the same investigator to avoid interobserver variability. RESULTS: The EOA promoted increased lower anterior facial height (LAFH), increased effective mandibular length, clockwise rotation of the mandible, retrusion and verticalization of the upper incisors, proclination and protrusion of the lower incisors, extrusion of the upper molars, mesial movement of the lower molars and anterior projection of the lower lip. CONCLUSION: Skeletal changes characterized by an increase in mandibular length and dentoalveolar changes with an emphasis on the verticalization and retrusion of the upper incisors, proclination of the lower incisors and mesial positioning of the lower molars were key to improving the occlusal relationship and esthetic facial factors. CLINICAL SIGNIFICANCE: The EOA is well indicated in patients with Class II malocclusion due to mandibular deficiency with increased overbite, proclined upper incisors and verticalized lower incisors.

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OBJECTIVES: The aim of this study was to evaluate the performance of CBCT three-dimensional (3D) reconstructions and sagittal sections for estimates of cervical vertebrae maturation index (CVMI). METHODS: The sample consisted of 72 CBCT examinations from patients aged 8-16 years (45 females and 27 males) selected from the archives of two private clinics. Two calibrated observers (kappa scores: ≥0.901) interpreted the CBCT settings twice. Intra- and interobserver agreement for both imaging exhibition modes was analyzed by kappa statistics, which was also used to analyze the agreement between 3D reconstructions and sagittal sections. Correlations between cervical vertebrae maturation estimates and chronological age, as well as between the assessments by 3D reconstructions and sagittal sections, were analyzed using gamma Goodman-Kruskal coefficients (α = 0.05). RESULTS: The kappa scores evidenced almost perfect agreement between the first and second assessments of the cervical vertebrae by 3D reconstructions (0.933-0.983) and sagittal sections (0.983-1.000). Similarly, the agreement between 3D reconstructions and sagittal sections was almost perfect (kappa index: 0.983). In most divergent cases, the difference between 3D reconstructions and sagittal sections was one stage of CVMI. Strongly positive correlations (>0.8, p < 0.001) were found not only between chronological age and CVMI but also between the estimates by 3D reconstructions and sagittal sections (p < 0.001). CONCLUSIONS: Although CBCT imaging must not be used exclusively for this purpose, it may be suitable for skeletal maturity assessments.

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Existem várias alterações nos arcos dentários, entre estas se encontram as de número, forma e tamanho dos dentes. O dente supranumerário representa um fator etiológico importante e frequente da má oclusão. Este trabalho teve o objetivo de avaliar a prevalência de dentes supranumerários nos pacientes tratados nos cursos de pós-graduação em Ortodontia da Universidade Cidade de São Paulo. A amostra, composta por 1117 radiografias panorâmicas de pacientes que se submeteram a tratamento ortodôntico corretivo, foi estudada quanto à distribuição da prevalência de dentes supranumerários entre os gêneros, os arcos dentários e as regiões bucais. A média de idade da amostra foi de 13,7 anos, sendo que 56% dos pacientes eram do gênero feminino e 44% do masculino. Do total analisada, apenas 18 pacientes (1,61%) apresentaram dentes supranumerários. Em relação ao gênero, verificou-se uma prevalência de 1,9% no gênero feminino, enquanto o gênero masculino apresentou prevalência de 1,2%. Na comparação entre os gêneros não se verificou diferença com significância estatística. No total foram constatados 24 dentes supranumerários, uma vez que existiram radiografias de pessoas com a presença de mais de um dente supranumerário. Destes 24 dentes, 16 estavam no arco superior e 8 no arco inferior. A partir da metodologia aplicada e dos resultados obtidos, pôde-se concluir que: a prevalência de dentes supranumerários foi de 1,61% dos indivíduos da amostra; não se pôde verificar diferença significante na prevalência de supranumerários entre os gêneros masculino e feminino; e a prevalência de dentes supranumerários foi estatisticamente semelhante para os arcos dentários superior e inferior, apesar de 66,7% deles terem sido localizados no arco superior

There are several tooth abnormalities in the dental arches, which can be in the number, shape or size of the teeth. The supernumerary teeth represent an important etiologic factor of malocclusion, quietly frequent. This study aimed to evaluate the prevalence of supernumerary teeth in the patients who has been orthodontic treated in the Graduation course of University of São Paulo City (UNICID). The sample, which consisted of 1117 panoramic radiographs of patients who have undergone orthodontic treatment, was studied on the distribution of the prevalence of supernumerary teeth gender, dental arches and mouth regions. The average age of the sample was 13.7 years, and 56% of patients were female and 44% male. Of the total analyzed, only 18 patients (1.61%) had supernumerary teeth. Regarding to gender, there was a prevalence of 1.9% among females, while males showed prevalence of 1.2%. In comparing genders, there was no statistically significant difference. A total of 24 supernumerary teeth were observed, once existed radiographs from people with more than one supernumerary tooth. Considering these 24 supernumerary teeth, 16 were located in the upper arch, while just 8 were in the lower arch. From the applied methodology and the results obtained, it could be concluded that: the prevalence of supernumerary teeth was 1.61% of individuals in the sample; There was not found significant differences in the prevalence of supernumerary between males and females; and prevalence of supernumerary teeth was statistically similar to the upper and lower dental arches, although 66.7% of them being located on the upper arch

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Em Ortodontia, a colagem de braquetes é um dos passos mais importantes durante o tratamento, principalmente na técnica Straight Wire, na qual os acessórios possuem uma forma específica para levar cada dente à posição prescrita, no que se refere à inclinação, angulação, ou mesmo adequando a posição vestíbulo-lingual das coroas, que variam devido às suas diferentes espessuras anatômicas. Outro ponto fundamental é a altura na qual os braquetes são posicionados, o que interfere diretamente na oclusão e na estética do sorriso. Se ocorre o posicionamento incorreto dos braquetes, além de contatos prematuros e outros possíveis danos, o profissional despenderá mais tempo realizando dobras compensatórias ou recolagens de acessórios. Assim sendo, o objetivo deste trabalho foi desenvolver e inscrever um projeto de patente, composto por um conjunto de posicionadores de braquetes ortodônticos, no intuito de promover um melhor e mais fácil posicionamento dos braquetes durante a colagem, diminuindo a chance de erros, otimizando o processo e tornando a rotina daclínica ortodôntica mais previsível e eficiente

In Orthodontics, brackets bonding is one of the most important steps during the treatment, especially in Straight Wire technique, in which accessories have an specific shape to led each tooth to its correct position, considering inclination, angulation, or even the buccal-lingual crowns position, that varies according to its thickness. Another important point is the height of the brackets, what interferes directly in the occlusion and in smile aesthetics. When an incorrect positioning of the brackets occurs, the clinician wastes time with rebonding or making wire bends. The aim of this study was to develop and submit a patent project, composed by a kit of brackets positioners, to promote a better and easier positioning during bonding, decreasing the chances of errors, optimizing the process and improving the orthodontic routine, with more predictability and efficiency

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O objetivo deste estudo foi verificar a variação do volume do disco articular da ATM em pacientes com DTM e em indivíduos de controle, correlacionando-a com diagnóstico de imagem de RM e com dados clínicos. Foram analisados 29 exames de ressonância magnética entre pacientes e controles, totalizando 58 ATMs, em cortes sagitais sequenciais das imagens de RM. O software livre MRIcro foi utilizado para delineamento manual dos limites anatômicos do disco articular e obtenção o volume do disco. Para analisar a correlação entre os volumes dos discos e as variáveis clínicas e por imagem, empregou-se o teste de Kruskal-Wallis. Para caracterizar e comparar as variáveis entre gênero e idade foi aplicado o Teste t de Student independente. Observou-se uma correlação entre o deslocamento do disco (p-valor = 0.001 para ATM direita e p-valor = 0.002 para ATM esquerda) e o volume do disco, que aumentou significativamente no grupo de pacientes. Não foi encontrada associação significativa entre gênero e volume dos discos direito e esquerdo (respectivamente; p-valor = 0,640 e 0,390). Concluiu-se que o volume do disco articular aumentou com a presença de desarranjo intra-articular.

The objective of this study was to measure the variation in the volume of temporomandibular joint disc in the patients with TMD compared with control individuals, in magnetic resonance images and clinical data. Twenty nine subjects have been analyzed between patients and control, totalizing 58 TMJ's in MR sequential sections. The software MRICro was used to anatomic delineation and to acquire the volume. Statistical analysis was conducted using Kruskal-Wallis test to correlate between disc volumes and clinical imaging variables. To compare the dependence on variables gender and age, Student Independence test was used. A correlation has been detected between disc displacement (p-value = 0.001 for right TMJ and p-value = 0.002 for left TMJ) and disc volume, which exhibited significant increase in patients. No significant correlation has been observed between gender and left and right disc volumes (respectively; p-value = 0,640 e 0,390). It was concluded that joint disc volume increased with the presence of internal derangement.

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O objetivo deste trabalho foi avaliar a deformação elástica de 14 marcas comerciais nos períodos de sete, 14, 21 e 28 dias. Três elos de cada elástico foram cortados e mensurados para a individualização do estiramento de 50% do tamanho original. Cinco amostras de cada fabricante foram colocadas em um template, onde permaneceram estiradas, presas por amarrilhos metálicos, imersas em saliva artificial (Saliform, Fórmula & Ação, São Paulo, Brasil), em estufa a 37°C. Para cada tempo, os elásticos foram removidos, aferidos por paquímetro digital e descartados. Os dados foram submetidos à estatística descritiva, Anova a dois critérios e teste de Tukey (5%). A Anova indicou diferença estatisticamente significativa entre as marcas comerciais e entre os tempos avaliados, assim como entre as possíveis interações entre os grupos. O teste de Tukey demonstrou a formação de grupos homogêneos entre as marcas, demonstrando que os grupos que melhor se comportaram foram: TP Orthodontics, GAC e Rock Mountain. Verificou-se ainda que, quanto maior o tempo que os elásticos permaneceram estirados, mais eles se deformaram. Concluiu-se que existe deformação plástica em todas as marcas, variando em função da marca, aumentada em função do tempo.

The aim of this work was to evaluate elastic deformation of 14 different brands after 7, 14, 21 and 28 days stretched. Three loops were cut and measured with a digital caliper to stretch individualization of 50% of the original size. Five samples of each brand were placed directly in the template where it remained stretched by metal ligadures in artificial saliva at 37°C. For each period, elastics were measured and discarded. Data was submitted to descriptive statistical analysis, 2-way Anova and Tukey test (5%). 2-way Anova showed statistically significant difference among trademarks, intervals measured; as well as possible interactions among groups. Tukey test showed best behavior for TP Orthodontics, GAC and Rock Mountain. It was also verified that elastics deformation was proportional to the stretching time. It was concluded that there was plastic deformation in all brands, varying among brands, increasing in function of time.

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O presente estudo avaliou a precisão do torque de tubos metálicos de primeiros molares inferiores na prescrição MBT, em seis marcas comerciais: Unitek 3M, Abzil, American Orthodontics, Morelli, Aditek e TP Orthodontics. Empregaram-se 20 tubos de cada marca, totalizando 120 tubos. As imagens ampliadas do perfil dos tubos foram obtidas por um único operador, com a utilização de um microscópio eletrônico de varredura, e os ângulos foram mensurados empregando-se o software AutoCAD 2008 (32 Bit). O ângulo vestibulolingual foi determinado pelos ângulos APO (ângulo da parede oclusal) e APC (ângulo da parede cervical), e foram comparados aos valores de referência de -20º. Para a análise estatística, utilizou-se o teste paramétrico de análise de variância (Anova) e o teste de Tukey HSD, com intervalo de confiança de 95% e nível de significância de p < 0,05. Considerando-se os ângulos APO e APC, a marca Aditek foi a que mais se distanciou do valor de prescrição. As marcas Unitek 3M e TP Orthodontics foram as que mais se aproximaram dos valores de prescrição, respectivamente, para os ângulos APC e APO. Concluiu-se que existem variações na inclinação vestibulolingual dos tubos avaliados, podendo comprometer o posicionamento final dos dentes.

The aim of this current study was to evaluate the torque precision of the first lower molar metallic tubes according to the MBT prescription in six different commercial brands: Unitek 3M, Abzil, American Orthodontics, Morelli, Aditek e TP Orthodontics. Twenty tubes of each brand were used, adding up to 120 tubes. The enlarged images of the tube profiles were obtained by only one operator using an electronic scanning microscope, and the angles were measured by using the AutoCAD 2008 (32 bits) software. The buccolingual angle was determined by the angles APO (occlusal wall angle) and APC (cervical wall angle) and they were compared to the reference values of -20°. For statistical analysis, the parametric test of analysis of variance (Anova) and Tukey HSD test were used, with a confidence interval of 95% and significance level of p < 0.05. Considering the APO and APC angles, the Aditek brand was the one which got the farthest from the prescription value. Unitek 3M and TP Orthodontics were the nearest ones to the prescription values, respectively, for the APC and APO angles. It was concluded that there are variations in the buccolingual inclination of the tubes which were evaluated, compromising the final positioning of the teeth.

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O presente artigo teve como objetivo ilustrar, por meio de um caso clínico, o tratamento de uma paciente jovem, portadora de uma má oclusão de Classe III de Angle com sobremordida exagerada. O tratamento foi realizado com o Prieto straight wire bracket (PSWb) e com a associação de uma placa de mordida provisória fixa (PMPF). A placa de mordida produziu uma desoclusão posterior e alguma liberdade aos incisivos inferiores, permitindo o rápido nivelamento da curva de Spee inferior por meio dos arcos do aparelho fixo lingual. Após 3 meses com a PMPF, esta foi removida e os bráquetes linguais foram fixados no arco superior. Os torques dos incisivos superiores foram corrigidos por meio dos arcos retangulares e o trespasse ideal foi conquistado após 26 meses de tratamento ativo.

This article aimed to illustrate, by means of a clinical case, the treatment of a young patient, with malocclusion Class III with severe overbite. The treatment was performed with the Prieto straight wire bracket associated to a fixed provisional bite plate. The bite plate has produced a posterior disocclusion and giving some freedom to the lower incisors, allowing rapid leveling of the lower curve of Spee through the arches of the lingual appliance. After 3 months the PMPF was removed and the lingual brackets were fixed in the maxillary arch. The upper incisors torque were corrected through the rectangular arch and the ideal overlap was achieved after 26 months of active treatment.

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O objetivo deste estudo foi avaliar as alterações dentárias sagitais e verticais resultantes da distalização de molares superiores. Foram analisadas as telerradiografias laterais em norma de 45º, dos lados direito e esquerdo, de 13 indivíduos, sendo dez do sexo masculino e três do sexo feminino, com média de idade de 14 anos e seis meses. Todos os indivíduos selecionados receberam, como mecanismo distalizador, o aparelho pêndulo modificado com molas removíveis, associado à ancoragem esquelética por meio de parafusos palatinos. Os molares superiores foram distalizados até a obtenção da sobrecorreção da relação molar em tempo médio de 6,97 meses. As alterações dentárias sagitais e verticais foram avaliadas aplicando-se o teste t para dados pareados, em nível de significância de 5%. Os resultados evidenciaram que os molares e pré-molares inclinaram-se para a distal, e os incisivos centrais superiores inclinaram-se para a lingual. Observou-se nas alterações verticais que os molares superiores apresentaram intrusão das coroas dentárias e extrusão dos ápices radiculares, demonstrando a ocorrência da inclinação dentária; os pré-molares e incisivos extruíram. Concluiu-se que o aparelho pêndulo associado à ancoragem esquelética é um método eficaz para a distalização de molares superiores, porém, observa-se o efeito da inclinação distal das coroas destes elementos dentários, e que os dentes da unidade de ancoragem acompanham o movimento dos molares, angulando-se para a distal.

The objective of this study was to evaluate the sagittal and vertical dental alterations resulting of maxillary molars distalization. The 45º cephalometric radiographs of the right and left sides were analyzed of 13 individuals, 10 males and 3 females with a mean age of 14 years and 6 months. All participants received as distalizer mechanism, the modified pendulum appliance with removable springs associated with skeletal anchorage by means of palatal screws. The maxillary molars distalization occurred with overcorrection beyond a Class I molar relationship completed in an average time of 6.97 months. The sagittal and vertical dental alterations were analyzed by applying the T paired test, in a significance level of 5%. The results showed that the molars and premolars had angulation change to the distal and central incisors moved to the lingual. Changes in vertical dimension were noted, the maxillary molars showed dental crowns intrusion and apical root extrusion, premolars and incisors had extrusive effect. We conclude that the pendulum appliance associated with skeletal anchorage is an effective method for maxillary molars distalization, however, there is the effect of distal tipping of the crowns of these dental elements and that the teeth of the anchorage unit follow the movement of the molars tilting toward the distal direction.

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