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OBJECTIVE: To evaluate and compare the friction of different ligature modes used in orthodontics, and to propose a new ligature model for conventional brackets ("H low-friction orthodontic ligature). MATERIALS AND METHODS: Samples were randomly divided into seven experimental groups: (1) resin H ligature (H3D), designed by the authors of this study and produced in a 3D printer, with conventional bracket; (2) metal H ligature (HFM), with conventional bracket; (3) passive self-ligating bracket (SLP); (4) "8" low-friction unconventional elastic (LT8), with conventional bracket; (5) loose conventional metal ligature (MLS), with conventional bracket; (6) conventional metal ligature fully tightened (MLT), with conventional bracket; (7) conventional elastic ligature (CEL), with conventional bracket-control. All samples were subjected to mechanical static friction testing using the EMIC DL 2000 universal testing machine. STATISTICAL ANALYSIS: To assess the normality requirement, the Shapiro-Wilk test was used, which showed a non-normal distribution for the means of the groups (p < 0.05). Therefore, statistical tests were performed to assess the existence of statistically significant differences between the groups through the Kruskal-Wallis, followed by Dunn's test, pairwise comparison, p < 0.05. RESULTS: The results obtained showed lower friction values for HFM (0.002 kgf), SLP (0.003 kgf), and LT8 (0.004 kgf)-these did not differ statistically from each other. These were followed by H3D (0.020 kgf), MLS (0.049 kgf), CEL (0.12 kgf), and, finally, MLT (0.21 kgf). CONCLUSION: The lowest friction value was found for the metal H ligature, similar to the self-ligating bracket and the "8" low-friction unconventional elastic. The resin H ligature presented intermediate friction values and the highest friction force was found for the MLT group.

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Resumo Este trabalho é uma descrição de um caso clínico de paciente portador de Síndrome de Treacher Collins (STC). O paciente em questão é menor de idade e foi submetido a tratamento ortodôntico interceptivo de má oclusão de classe II, característica da síndrome devido à retrognatia, no Centro de Atenção e Pesquisa em Anomalia Craniofacial (CEAPAC), Cascavel ­ PR. As disostoses faciais são um conjunto de anomalias raras do esqueleto craniofacial, a mais comumente descrita é a STC, que é uma doença rara, sem predisposição por sexo ou raça. Os sintomas e a severidade desta síndrome diferem de indivíduo para indivíduo, mesmo entre membros da mesma família. Suas características comuns são as anormalidades dos pavilhões auriculares, hipoplasia dos ossos da face, obliquidade antimongolóide das fendas palpebrais com coloboma palpebral inferior e fissura palatina e o principal problema anatômico é a hipoplasia do terço médio da face e o hipodesenvolvimento da mandíbula e mento, o que leva o paciente portador desta síndrome apresentar por suas características faciais uma má oclusão de classe II muitas vezes associadas à mordida aberta, além de outros problemas orais como, por exemplo, as patologia das glândulas salivares, respiração bucal e apinhamento dentário. O tratamento ortodôntico intercepetivo do menor, embora após terminado tenha permanecido com má oclusão de classe II, obteve mudanças em parâmetros cefalométricos e faciais do paciente.(AU)

Abstract This work is a description of a clinical case of a patient with Treacher Collins Syndrome (CTS). The patient in question is younger and underwent interceptive orthodontic treatment of class II malocclusion, characteristic of the syndrome due to retrognathia, at the Center for Attention and Research in Craniofacial Anomaly (CEAPAC), Cascavel ­ PR. Facial dysostosis is a set of rare anomalies of the craniofacial skeleton, the most commonly described being CTS, it is a rare disease, without predisposition by sex or race. The symptoms and severity of this syndrome differ from individual to individual, even among members of the same family. Its common features are auricular pavilion abnormalities, facial bone hypoplasia, antimongoloid obliquity of the palpebral fissures with lower palpebral coloboma and cleft palate, and the main anatomical problem is hypoplasia of the middle third of the face and hypodevelopment of the mandible and chin, which Due to their facial characteristics, patients with this syndrome have a Class II malocclusion, often associated with an open bite, in addition to other oral problems such as salivary gland pathology, mouth breathing and dental crowding. The minor's interceptive orthodontic treatment, although after it ended, he remained with class II malocclusion, resulted in changes in the patient's cephalometric and facial parameters.(AU)

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This study evaluated the effect of auricular acupuncture (AA) on physical (PA) and emotional (EA) aspects of patients with temporomandibular disorders (TMDs) and compared the effect of AA with those of Sham and occlusal splints (OS). In accordance with the CONSORT guidelines, patients with TMDs were evaluated by axes I and II of the RDC-TMD. The patients were allocated among three groups: OS, Sham and AA; and followed for 8 weeks. Both intragroup and intergroup evaluation for quantitative variables were analyzed with ANOVA, one-way, followed by the Tukey test. Qualitative variables were analyzed with the Kruskal-Wallis, and Dunn tests (intergroup evaluation) and for intragroup analyses, the Friedman and Wilcoxon tests were applied. At the end of the experiment, the chi-squared test was applied to compare the three groups with respect to the number of variables that had shown improved scores. The adopted level of significance for all tests was α = 5%. Intragroup analysis showed that, in the Sham group, no improvement in performance was seen in either EA and significant was improvements in 5 variables for 9 for PA, while in the AA group, significant improvements were observed in 2 variables for EA and in 9 for PA. In the OS group at the end of this study, significant improvements were observed in 8 and 8 variables for EA and PA, respectively. The analysis of therapies used revealed that the number of variables exhibiting significantly improved outcomes after treatment was similar between the AA and OS groups, whereas the sham group showed statistically significant differences when compared with the other two groups. In conclusion, this study demonstrated that AA applied at a specific TMJ ear point was able to bring about improvements in patients with TMDs, with outcomes similar to those in patients treated with an OS. CLINICAL TRIAL REGISTRATION: RBR-69ynnw (Brazilian Registry of Clinical Trials).

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Polymeric aesthetic aligners were introduced in orthodontics as an innovative alternative to fixed appliances, however, their compositions and the thermal molding process may influence the biomechanical characteristics of these aligners. In this study four different clear aligner brands were used, ACE 035 Essix, C + Essix, Crystal 0.75 and Crystal 1.0, whose aim was to identify the thermal-processing influence on the mechanical and physicochemical properties of these materials, and to suggest a orthodontic sequence of wear for these appliances to achieve more effective treatment results. For the tensile tests the sample size calculation was based on probability distributions from the F test. The effect size used was 0.3, type 1 error of 0.05. Statistical Yield strength and Young's Modulus results were evaluated using the Shapiro-Wilk test. The groups were compared using the parametric test of analysis of variance, with Tukey post-test. Differences were statistically considered at the p < 0.05. The Infrared spectroscopy analysis showed no changes in the samples' chemical structure after thermal-processing. However, in the polypropylene aligner, differences were verified in the region attributed to the crystalline phase. Differential Scanning Calorimetry analysis for the same sample showed a crystallinity fraction decrease due to relaxation between polymer chains after molding. In the tensile tests evaluated, the tensile strength and 'Young's modulus presented higher values for aligners containing 100% polyethylene terephthalate glycol. Performing an analogy exercise of the properties of orthodontic wires used in conventional fixed appliances and, relating them to orthodontic plastics, aligners composed of different materials and/or thicknesses could be used in increasing sequence in terms of the modulus of elasticity, starting with C+, which has a lower elastic modulus value, using the ACE 035 as an intermediate and finishing with the Crystal 0.75 and 1.0, providing the desired stiffness to the aligners for the final phase.

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Resumo Inúmeras variáveis são consideradas em uma oclusão normal, uma delas é a homeostasia da musculatura facial e sua harmonia com os ossos e dentes. Diversos fatores podem levar a alterações na funcionalidade muscular. Um exemplo é a queimadura facial, na qual é comum a formação de cicatrizes hipertróficas que provocam disfunção nas estruturas musculares e impactam no crescimento facial e no desenvolvimento da dentição. Paciente K.R.S, sexo feminino, 15 anos, procurou tratamento no Centro de Atenção e Pesquisa de Anomalias Craniofaciais (CEAPAC) com queixa de "dentes tortos". Durante anamnese relatou que quando criança sofreu um acidente doméstico que acarretou queimaduras na face e parte do corpo. A paciente era portadora de má oclusão de Classe I de Angle e lingualização dos incisivos superiores e inferiores. Observou-se atresia das arcadas dentárias e apinhamento moderado. Realizou-se a expansão rápida da maxila e expansão dentária inferior com a placa lábio ativa, seguida de alinhamento e nivelamento dos dentes com aparelho fixo. Na fase de contenção utilizaram-se placas de Hawley (superior e inferior), além de uma contenção fixa inferior. Os tratamentos de expansão das arcadas e alinhamento se mostraram viáveis e previsíveis. Entretanto a estabilidade tem prognóstico duvidoso, o que levou os autores a indicarem o uso das contenções por tempo indeterminado.(AU)

Abstract Numerous variables are considered in a normal occlusion, one of those is the homeostasis of the facial musculature and its harmony with bones and teeth. Several factors can lead to change in muscle functionality. An example is the facial burn injury in which it is common formation of hypertrophic scars that cause muscle structures dysfunction and impact on facial growth and dentition development. Patient K.R.S, 15-years-old, female, sought treatment at the Center for Attention and Research of Craniofacial Anomalies (CEAPAC) complaining of "crooked teeth". She reported during anamnesis that when she was a child, she suffered a domestic accident which caused facial, and body burn injury. The patient had Angle Class I malocclusion and upper and lower incisor lingualization. Dental arch atresia and moderate crowding were observed. Rapid maxillary expansion and lower dental expansion were performed with the lip bumper, followed by teeth alignment and leveling with a fixed appliance. In the retainment phase, Hawley plates (upper and lower) were used in addition to a fixed lower retainer. The treatment of arch expansion and alignment proved to be viable and predictable, however, the stability has a dubious prognosis, which led the authors to indicate the use of retainers indefinitely. (AU)

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OBJECTIVE: This study evaluates the bond strength of two compositions of aesthetic translucent zirconia (TZ). MATERIALS AND METHODS: For this evaluation, test specimens were prepared from ICE Zirkon TZ and Prettau Anterior zirconia (PAZ) that were stored in distilled water at 37°C for two time periods: T1 (24 h) and T2 (90 days) to simulate aging. Two factors were evaluated for the samples-ceramic and aging time. The samples were subjected to tests of microshear strength and fracture type and were evaluated using scanning electron microscopy. RESULTS: The results were analyzed using the D'Agostino test, analysis of variance, and Tukey's test (p < 0.01). Statistically significant differences were observed for ceramic type and aging time. CONCLUSION: The results showed that PAZ provides significantly superior performance to TZ at the two aging times evaluated.

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ABSTRACT Objective: This study aimed to assess the bond strength and marginal microleakage in composite resin restorations, using the Single Bond Universal adhesive system associated with Ultralux (halogen) and Bluephase (LED) light curing units. Methods: For bond strength, 80 healthy human third molars were divided into halogen light (n=40) and LED (n=40), and subdivided according to the following application techniques for the adhesive system: etch-and-rinse (enamel), self-etching (enamel), etch-and-rinse (dentin), and self-etching (dentin). The teeth were subjected to the microtensile test and the fracture pattern was observed under an optical microscope at 40X magnification; they were analyzed by ANOVA, and Fisher and Tukey's tests (5%). For the marginal microleakage test, 120 class II cavities were prepared in 60 healthy human third molars that were randomly divided into halogen light (n=30) and LED (n=30), and subdivided according to the following application techniques for the adhesive system: etch-and-rinse, selective etching, and self-etching. The teeth were thermocycled 2000 times (±5/55°C), stained in 5% basic fuchsin and sectioned for qualitative and quantitative assessments; they were analyzed by Kruskall-Wallis and Dunn tests (5%). Results: For the bond strength of enamel and dentin, the adhesive application with prior acid etching was better than self-etching (p<0.0001), regardless of the type of light curing unit (p<0.05). Etch-and-rinse showed the lowest microleakage values (p<0.0001). Conclusion: Etch-and-rinse obtained the best results relative to the other application techniques for the adhesive system in both tests, regardless of the type of light curing unit.

RESUMO Objetivo: Avaliar a resistência de união e microinfiltração marginal em restaurações de resina composta, utilizando sistema adesivo Single Bond Universal associado com fotoativadores Ultralux (halógeno) e Bluephase (LED). Métodos: Para resistência de união, oitenta terceiros molares humanos hígidos foram divididos: Halógena (n=40); LED (n=40), sendo subdivididos de acordo com a técnica de aplicação do sistema adesivo: condicionamento total-esmalte; autocondicionante-esmalte; condicionamento total-dentina; autocondicionante-dentina. Os dentes foram submetidos ao teste de microtração e o padrão de fratura foi observado em microscópio ótico - 40X de aumento, analisadas pelos testes ANOVA, Tukey e Fisher (5%). Para o ensaio de microinfiltração marginal, 120 cavidades classe II foram preparadas em sessenta terceiros molares humanos hígidos, aleatoriamente divididos: Halógena (n=30); LED (n=30) e subdivididos de acordo com a técnica de aplicação do sistema adesivo: condicionamento total; condicionamento seletivo; autocondicionante. Os dentes foram termociclados 2000 vezes (±5/55ºC), corados em fucsina básica 5% e seccionados para avaliações qualitativa e quantitativa, analisados pelos testes Kruskall-Wallis e Dunn (5%). Resultados: Para resistência de união em esmalte e dentina, a aplicação do adesivo com condicionamento ácido prévio, foi melhor que o autocondicionante (p<0.0001), independentemente do tipo de fotoativador utilizado (p<0.05). O condicionamento total mostrou os menores valores de microinfiltração, (p<0.0001). Conclusão: O condicionamento total, obteve os melhores resultados em relação às outras técnicas de aplicação do sistema adesivo em ambos os testes, independentemente do tipo de aparelho fotoativador.

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A obtenção de uma oclusão funcionalmente equilibrada é uma meta perseguida pelos ortodontistas, e um dos pré-requisitos para isso é a existência de proporcionalidade entre os tamanhos mésio-distais dos dentes superiores e inferiores. Com a intenção de localizar o excesso de massa dentária e dirigir a conduta clínica, a análise de Bolton estabelece proporções ideais para regiões anterior e total do arco dentário, evidenciando as discrepâncias. O objetivo deste estudo foi comparar a discrepância de Bolton entre as diferentes más oclusões sagitais e entre diferentes protocolos de extração de quatro pré-molares, avaliando a tendência de se promover discrepância de Bolton nos diferentes protocolos de extração específicos para a camuflagem das más oclusões. Em modelos de estudo de 86 pacientes, com média etária de 18,6 anos, sendo que 31 destes eram portadores de má oclusão de Classe I, 29 pacientes de Classe II e 26 de Classe III, mediu-se as discrepâncias de Bolton com a utilização de paquímetro. Comparou-se as médias dos diâmetros mésio-distais e suas proporções entre grupos de más oclusões, protocolos de extração e protocolos específicos para camuflagem, através da análise de variância. Não ocorreram diferenças estatísticas para discrepância anterior e total entre os grupos de más oclusões avaliados e entre os grupos de protocolos de extração. Com relação aos protocolos de extração para camuflagem, os pacientes Classe III tenderam a apresentar maior discrepância de Bolton às outras más oclusões. É válido considerar esses aspectos durante o plano de tratamento ortodôntico para que a finalização do mesmo não seja dificultada. (AU)

Obtaining a static and functionally balanced occlusion is a goal pursued by orthodontists, and one of pre requirements to it is the existence of proportionality between the mesial-distal sizes of upper and lower teeth. In order to locate the excess dental mass and direct clinical management, the Bolton analysis establishes ideal proportions for both anterior and total arch, highlighting the discrepancies. The objectives of this study were to compare the Bolton discrepancy between the malocclusions and between four premolars extraction protocols, and evaluate the tendency to promote Bolton discrepancy in different specific extraction protocols for camouflage of malocclusions. In plaster models of 86 patients, with a mean age of 18.6 years old, which 31 were suffering from malocclusion of Class I, 29 with Class II and 26 with Class III, it was measured Bolton discrepancies with the use of paquimeter. It was compared the mean values of mesiodistal diameters and their proportions between groups of malocclusion, extraction protocols, and specific protocols for camouflage, through the variance analysis. There were no statistical differences for anterior and total tooth size discrepancy between malocclusion groups and extraction protocols groups. Regarding the extraction protocols for camouflage, patients with Class III tended to show more Bolton discrepancy than other malocclusions. It is worth considering these aspects during orthodontic treatment plan for thereof completion won't be hampered.(AU)

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Objetivo: Avaliar a influência de diferentes soluções de irrigação cavitária sobre a resistência de união de um cimento resinoso de dupla polimerização. Material e Método: A partir de incisivos bovinos, foram obtidos 4 grupos (n=15), divididos aleatoriamente de acordo com a solução irrigadora empregada na limpeza cavitária, sendo: G0 - soro fisiológico + condicionamento ácido; G1 ­ EDTA + condicionamento ácido; G2 - Clorexidina 2% + condicionamento ácido + clorexidina 2% e G3 - soro fisiológico + condicionamento ácido + clorexidina 2%. Foram confeccionados cilindros de cimento resinoso para cada coroa, utilizando-se uma matriz de Tygon com diâmetro interno de 1 mm e altura de 2 mm. O teste de resistência adesiva por microcisalhamento foi realizado após 3 meses de armazenamento dos espécimes em soro fisiológico a 37ºC. Os dados foram submetidos ao teste de Kruskall-Wallis, seguido do teste de Dunn (p<0,05). Resultados: Os grupos G0, G1 e G3 não apresentaram diferenças significativas entre si (p>0,05). Os menores valores foram observados no grupo G2 (p<0,05). Conclusões: As soluções irrigadoras EDTA e soro fisiológico utilizadas previamente ao condicionamento ácido da dentina não interferiram, significativamente, na resistência de união, porém, a solução de clorexidina utilizada após o condicionamento ácido influenciou negativamente nos valores de resistência de união.

Objectives: This study aimed to evaluate the influence of different cavity irrigation solutions on the bond strength of a dual-curing resin cement. Methods: From bovine incisors, 4 groups (n=15), were randomly divided according to the irrigating solution for cavity cleaning: G0 ­ saline + acid etching; G1 ­ EDTA + acid etching; G2: Chlorhexidine 2% + acid etching + Chlorhexidine 2%; and G3 ­ Saline + acid etching + Chlorhexidine 2%. Resin cement cylinders were made for each crown, using a Tygon matrix with internal diameter of 1 mm and height of 2 mm. The specimens were stored for 3 months at 37oC, and then subjected to microshear tests. Data were statistically analyzed by Kruskal-Wallis test followed by Dunn (p<0.05). Results: There were no statistically significant differences between G0, G1 and G3 groups (p>0.05). The lowest values were observed in G2 group (p<0.05). Conclusion: The irrigation solutions EDTA and saline used before to the acid etching of dentin did not interfere, significantly, in the bond strength, however, the solution of chlorhexidine used after the acid etching influenced negatively.

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OBJECTIVE: The objective of this study was to clinically and radiographically assess the peri-implant conditions of implants used as orthodontic anchorage. METHODS: Two groups were studied: 1) a test group in which osseointegrated implants were used as orthodontic anchorage, with the application of 200-cN force; and 2) a control group in which implants were not subjected to orthodontic force, but supported a screw-retained prosthesis. Clinical evaluations were performed three, six and nine months after prosthesis installation and 1- and 3-year follow-up examinations. Intraoral periapical radiographs were obtained 30 days after surgical implant placement, at the time of prosthesis installation, and one, two and three years thereafter. The results were compared by Kruskal-Wallis test. RESULTS: There was no statistically significant difference in clinical probing depth (p = 0.1078) or mesial and distal crestal bone resorption (p = 0.1832) during the study period. After three years of follow-up, the mean probing depth was 2.21 mm for the control group and 2.39 mm for the test group. The implants of the control group showed a mean distance between the bone crest and implant shoulder of 2.39 mm, whereas the implants used as orthodontic anchorage showed a mean distance of 2.58 mm at the distal site. CONCLUSION: Results suggest that the use of stable intraoral orthodontic anchorage did not compromise the health of peri-implant tissues or the longevity of the implant.

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