Aim To evaluate the maxillary dentition effects of the extrusion arch for anterior open bite (AOB) correction in mixed dentition patients. Materials and methods Fourteen subjects with an initial mean age of 9.17 ± 1.03 years presenting with dentoalveolar AOB (mean − 1.28 ± 1.46 mm) and normal facial pattern (FMA = 25.76°) were treated with an extrusion arch. The mean treatment period was 7.79 ± 2.58 months. Lateral cephalograms and dental models were taken before (T0) and after the correction of AOB (T1). Data were analyzed using paired t test to evaluate differences between T0 and T1. For all tests, a significance level of P < .05 was used. Results All patients achieved positive overbite at T1, with a mean increase of 3.07 mm. The maxillary incisors extruded 1.94 mm. Retroclination of the maxillary incisors (− 6.15°) and an increase in the interincisal angle (5.57°) were observed. There was a significant decrease in the distance between the incisal edge of the maxillary incisors and the molars (− 2.21 mm). There was significant mesial tipping of the maxillary molar (− 11.49°). Significant reductions of overjet (− 1.65 mm), arch perimeter (− 3.02 mm), and arch length (− 2.23 mm) were noted. The transverse maxillary intermolar distance did not change significantly. Conclusions The use of a maxillary extrusion arch was effective in the treatment of AOB. Overbite increased due to incisor extrusion, as well as retroinclination and overjet reduction. However, side effects, such as mesial molar tipping and decreases in arch perimeter and length might occur.

Objective: The purpose of this study was to determine the perception of smile esthetics among orthodontists and laypersons with respect to unilateral maxillary canine torque variations in a frontal smile analysis. Methods: Full face and close-up smile photographs of two subjects (1 man and 1 woman) were used. Both smiles displayed healthy maxillary anterior dentitions. The images were digitally altered to obtain a bilateral 0° torque in the maxillary canines. From this image, unilateral variations of the left canine were made with -15°, -10°, -5°, 0°, +5°, +10° and +15°. Final images were randomly assembled into an album that was given to 53 orthodontists and 53 laypersons. Each rater was asked to evaluate the attractiveness of the images using visual analog scales. Data collected were statistically analyzed with one-way analysis of variance with Tukey post-hoc test and the unpaired Student t test. Results: For orthodontists, most attractive smiles were those with 0°, -5° and -10°. For laypersons, most attractive smiles were those with 0°, -5°, -10°, -15° and + 5°. For both groups, the lowest scores were given for the smiles with +10° and +15° torque. When comparing the perceptions of the orthodontists and laypersons, they did not show statistical differences in most situations. Moreover, in general, there was no significant difference between the full-face and close-up assessments of the smiles. Conclusions: The present findings indicated that smiles with unilateral palatal (negative values) maxillary canine torque variations were more tolerated than smiles with buccal crown torque (positive values) variations.

Anterior open bite affects the child population by approximately 20%, with great aesthetic-functional impairment due to dental-skeletal changes, which may involve the presence of posterior crossbite. The objective was to present the anterior open bite correction associated with posterior crossbite with the use of a removable palatal crib. Patient during the mixed dentition phase presented an anterior open bite caused by a pacifier sucking habit and secondary lingual interposition. The treatment protocol consisted of the use of removable expander with palatal crib and nocturnal use of the chincup. The anterior open bite was corrected, and the best transverse relation of the arches was obtained. The precocious treatment using the palatal crib associated to the chincup allows to achieve favorable results in the resolution of the anterior open bite. Keywords: Open Bite. Malocclusion. Orthodontics, Interceptive. ResumoA mordida aberta anterior acomete a população infantil em aproximadamente 20%, com grande comprometimento estético-funcional em decorrência das alterações dentoesqueléticas, podendo envolver a presença de mordida cruzada posterior. O objetivo do estudo foi apresentar a correção da mordida aberta anterior associada à mordida cruzada posterior com a utilização de grade palatina removível. Paciente em fase de dentadura mista, apresentava mordida aberta anterior ocasionada por um hábito de sucção de chupeta e interposição lingual secundária. O protocolo de tratamento consistiu na utilização de expansor removível com grade palatina e uso noturno da mentoneira. A mordida aberta anterior foi corrigida e melhor relação transversal dos arcos foi obtida. O tratamento precoce utilizando grade palatina associada à mentoneira permite alcançar resultados favoráveis na resolução da mordida aberta anterior. Palavras-chave: Mordida Aberta. Má Oclusão. Ortodontia Interceptora.

OBJETIVO: Avaliar a força de atrito e a rugosidade de superfície de três diferentes fios de níquel-titânio. MATERIAL E MÉTODOS: Foram avaliados três fios distintos, todos da mesma espessura (0,016” x 0,022”): NiTi Superelástico Flexy Blue-Ti (Orthometric, Marí- lia / SP, Brasil); NiTi Superelástico Black (Ortho-Organizers, Carlsbad, CA, EUA); e NiTi Thermal Smart (Orthometric, Marília / SP, Brasil). Para cada tipo, dez amostras, de 30mm cada, foram testadas. Os fios foram adaptados em um braquete autoligado de incisivo inferior, fixado em um conector de PVC com resina acrílica, em duas angulações diferentes (0o e 5o), simulando situações clínicas distintas. A força de atrito foi avaliada em uma máquina universal de ensaios (EMIC), e a rugosidade de superfície foi avaliada utilizando-se um rugosímetro. Para verificação da normalidade dos dados, adotou-se o teste Kolmogorov-Smirnov; e, para comparação entre os grupos, o teste ANOVA, seguido do teste de Tukey, com nível de significância de 0,05. RESULTADOS: O fio Blue-Ti apresentou menor atrito (0,065 Mpa), seguido do fio NiTi Black (0,174 Mpa) e do fio NiTi termoativado (0,244 Mpa). Ao se avaliar a rugosidade de superfície, o menor valor foi encontrado no fio NiTi Black (0,254 Ra), seguido pelos fios Blue-Ti (0,269 Ra) e NiTi-termo (0,358 Ra), sem, no entanto, apresentar diferença estatisticamente significativa. CONCLUSÃO: O fio superelástico Blue-Ti apresentou menor atrito, em ambas as angulações (0o e 5o). Quanto à rugosidade de superfície, não houve diferença entre os fios estudados.

A mordida aberta anterior atinge cerca de 20% da população infantil e apresenta diversas formas de tratamento. OBJETIVOS: o presente trabalho descreve o uso de um arco de extrusão para o tratamento da mordida aberta anterior em um paciente na fase de dentição mista.