Superimposition of virtual models using palatal rugae and maximum habitual intercuspation.

INTRODUCTION: The superimposition of 3 dimensions (3D) digital models has been increasingly used for evaluating dental changes resulting from orthodontic treatment, and different superimposition techniques have been described. Although the maxilla has areas with greater stability for superimposition, such as the palatal rugae, there is still no reliable method for superimposing models of the lower arch. OBJECTIVE: Therefore, this article aims to describe a technique for superimposing virtual models. METHODS: To evaluate pre- and post-orthodontic treatment changes, the Geomagic Qualify 2013 software (3D Systems®, Rock Hill, South Carolina, USA) was used, with reference points in the maxilla, including the rugae and a reference area in the palate and midpalatal raphe. The lower arch was superimposed using the maximum habitual intercuspation (MHI) model as reference. RESULTS AND CONCLUSION: 3D models superimposition using palatal rugae and MHI occlusion seems to offer satisfactory results in the interpretation of clinical changes at different follow-up moments in terms of development and/or orthodontic treatment.

Superimposition of virtual models using palatal rugae and maximum habitual intercuspation

ABSTRACT Introduction: The superimposition of 3 dimensions (3D) digital models has been increasingly used for evaluating dental changes resulting from orthodontic treatment, and different superimposition techniques have been described. Although the maxilla has areas with greater stability for superimposition, such as the palatal rugae, there is still no reliable method for superimposing models of the lower arch. Objective: Therefore, this article aims to describe a technique for superimposing virtual models. Methods: To evaluate pre- and post-orthodontic treatment changes, the Geomagic Qualify 2013 software (3D Systems®, Rock Hill, South Carolina, USA) was used, with reference points in the maxilla, including the rugae and a reference area in the palate and midpalatal raphe. The lower arch was superimposed using the maximum habitual intercuspation (MHI) model as reference. Results and Conclusion: 3D models superimposition using palatal rugae and MHI occlusion seems to offer satisfactory results in the interpretation of clinical changes at different follow-up moments in terms of development and/or orthodontic treatment.

RESUMO Introdução: A sobreposição de modelos digitais em três dimensões (3D) tem sido cada vez mais utilizada como forma de avaliar as alterações dentárias decorrentes do tratamento instituído, e diferentes técnicas de sobreposição têm sido descritas. Apesar de a maxila apresentar áreas de maior estabilidade para sobreposição dos modelos, como as rugas palatinas, ainda não existe um método confiável para a sobreposição da arcada inferior. Objetivo: O presente artigo tem como objetivo descrever uma técnica de sobreposição de modelos virtuais. Métodos: Para avaliar as alterações pré e pós-tratamento ortodôntico, foi usado o software Geomagic Qualify 2013 (3D Systems®, Rock Hill, Carolina do Sul, EUA) , utilizando pontos de referência na maxila na região das rugas palatinas e uma área de referência na zona do palato e rafe palatina mediana. Já a arcada inferior foi sobreposta utilizando o modelo em máxima intercuspidação habitual (MIH) como referência. Resultados e Conclusão: A sobreposição de modelos utilizando as rugas palatinas e a oclusão em MIH parece oferecer resultados satisfatórios na interpretação das alterações clínicas entre momentos diferentes de acompanhamento, seja do crescimento/desenvolvimento e/ou resultados do tratamento ortodôntico.

Comparison between dentistry and nondentistry undergraduate students' selfperception regarding the aesthetics of their own smile and facial profile

Introduction: the study aimed to compare how undergraduate dentistry students (DS) and non-dentistry students (NDS) analyze and classify their own smile and facial profile. Materials and Methods: the cross-sectional study questionnaire included topics for the identification of the respondent; Likert scale and aesthetic component of the Index of Orthodontic Treatment Need (IOTN) to assess satisfaction with one's own smile; facial profile attractiveness using Turkkahraman and Gokalp scale and previous history of orthodontic treatment. Intra and intergroup data were analyzed by chi-square test with 95% confidence (p<0.05) using SPSS 13.0 software. Results: 483 questionnaires were answered, 166 from DS and 317 from NDS. Most participants considered their occlusion as ideal and pleasant (DS - 79.27%; NDS - 79.8%) and their profile as slightly convex (DS - 80.6%; NDS - 76%). The slightly convex profile was also preferred by both groups for both genders. 71% of the DS and 66.0% of the NDS reported having undergone orthodontic treatment. Most respondents were satisfied or very satisfied with their smile, however the NDS had a higher prevalence of students very satisfied with their smile (p<0.05). Conclusion: the choice of course does not seem to have any influence on the analysis and classification of the smile and facial profile, perhaps because most of them have already undergone orthodontic treatment.

Introdução: o objetivo deste estudo foi observar como estudantes de graduação analisam e classificam seu próprio sorriso e perfil facial, comparando os resultados entre estudantes de odontologia (EO) com não estudantes de odontologia (NEO). Materiais e Métodos: o questionário respondido pelos participantes incluiu tópicos para identificação dos indivíduos; escala Likert e componente estético do Índice de Necessidade de Tratamento Ortodôntico (IOTN) para avaliar a satisfação com o próprio sorriso; atratividade facial com escala de Turkkahraman and Gokalp e história prévia de tratamento ortodôntico. Os dados intra e intergrupos foram analisados pelo teste qui-quadrado com 95% de confiança (p<0,05) utilizando o software SPSS 13.0. Resultados: foram obtidas 483 respostas, sendo 166 do grupo EO e 317 do grupo NEO. A maioria dos participantes considerou sua oclusão ideal e agradável (EO - 79,27%; NEO - 79,8%) e seu perfil levemente convexo (EO - 80,6%; NEO - 76%). O perfil levemente convexo também foi preferido por ambos os grupos para ambos os sexos. 71% dos EO e 66,0% dos NEO relataram ter feito tratamento ortodôntico. A maioria dos respondentes estava satisfeita ou muito satisfeita com seu sorriso, porém o NEO teve maior prevalência de alunos muito satisfeitos com seu sorriso em relação ao grupo EO (p<0,05). Conclusão: a escolha do curso parece não ter influência na análise e classificação do sorriso e perfil facial, talvez porque a maioria dos participantes já tenha realizado tratamento ortodôntico.

Do low-cost 3-dimensional printers produce suitable dental models?

INTRODUCTION: When choosing a 3-dimensional printer for dental models, the cost-benefit ratio should be evaluated. The purpose of this study was to evaluate the accuracy, precision, cost, and time taken to prepare and print using different low-cost techniques (2 digital light processing [DLP] and 1 fused filament fabrication [FFF] printer) compared with the reference proven to be clinically accepted (PolyJet). METHODS: For this purpose, the upper and lower virtual models of 5 patients were printed using: (1) DLP printer Moonray, (2) DLP printer Anycubic, (3) DLP printer Moonray with Anycubic resin, (4) Filament printer UpMini 2 (FFF), and (5) Polyjet printer Objet Eden500V. One of the virtual models was also printed 4 consecutive times on each printer to allow consistency assessment. Afterward, the 14 printed resin models were scanned, and their accuracy was evaluated by model superimposition using Geomagic Qualify software (3D Systems, Rock Hill, SC). A digital caliper was also used to obtain linear measurements. All measurements were carried out by a calibrated examiner. RESULTS: The results showed that all printers produced similar results, although Moonray with Anycubic resin showed loss of accuracy and Anycubic showed inconsistent vertical dimensions. The printing cost and time consumed from each pair of models were calculated for the overall printing process, analyzing which would have the best cost-benefit ratio. CONCLUSIONS: Polyjet printing was considered the fastest method but with the highest cost. FFF printing was the lowest printing and input cost but was considerably more time-consuming. There was a balance in both DLP printers, and they were considered the best cost-benefit ratio for small independent dental offices.

Levels of gingival crevicular fluid matrix metalloproteinases in periodontally compromised teeth under orthodontic forces.

OBJECTIVE: To examine levels of matrix metalloproteinases (MMPs)-1, -2, -3, -7, -8, -12, and -13 in the gingival crevicular fluid (GCF) of periodontally compromised teeth at different time points during orthodontic movement. MATERIALS AND METHODS: Ten controlled periodontitis subjects were submitted to orthodontic treatment. One dental arch was subjected to orthodontic movement, and teeth in the opposite arch were used as controls. GCF samples were collected from the lingual sites of two movement and two control incisors 1 week before orthodontic activation (-7 d), immediately after orthodontic activation, and after 1 hour, 24 hours, and 7, 14, and 21 days. Multiplexed bead immunoassay was used to measure MMPs in GCF. Data were analyzed using Friedman and Wilcoxon statistical tests. RESULTS: The only significant change found over time was in the levels of MMP-1 in the movement group (P < .05). When the two groups were compared after activation, the only statistically significant difference found was in levels of MMP-12 24 hours after activation (P < .05). CONCLUSIONS: Our findings suggested that the orthodontic movement of periodontally compromised teeth without active pockets did not result in significant changes in the GCF levels of MMPs.

Efficiency of light-emitting diode and halogen units in reducing residual monomers.

INTRODUCTION: In this in-vitro study, we aimed to compare the residual monomers in composites beneath brackets bonded to enamel, using a light-emitting diode (LED) or a halogen unit, and to compare the residual monomers in the central to the peripheral areas of the composite. METHODS: Twenty bovine teeth preserved in 0.1% thymol were used in this study. Ten teeth were used to standardize the thickness of the composite film, since different thicknesses would cause different absorbance of light. Brackets were bonded to 10 bovine incisors, with the halogen light (n = 5) and the LED (n = 5). The brackets were debonded, and the remaining composite on the enamel surface was sectioned in 2 regions: peripheral (0.8 mm) and central, resulting in 2 subgroups per group: central halogen (n = 5), peripheral halogen (n = 5), central LED (n = 5), and peripheral LED (n = 5). The spectrometric analysis in the infrared region was used to measure the free monomers with the attenuated total reflectance method. RESULTS: Normal distribution was tested by using the Kolmogorov-Smirnov test. Data were compared by 2-way analysis of variance (ANOVA) at P <0.05. The LED group showed fewer residual monomers than did the halogen group (P = 0.014). No differences were found among the regions (P = 0.354), and there were no interactions between light type and region (P = 0.368). CONCLUSIONS: LED leaves less residual monomer than does the halogen light, even with half of the irradiation time; there were no differences between the central and peripheral regions, and no interaction between light type and region.

Orthodontic management of a patient with impacted and transposed mandibular canines.

This patient report describes the treatment of a 10-year-old female with complete transposition of her impacted mandibular canines and lateral incisors. The patient had a Class I occlusion, and her mandibular lateral incisors were in crossbite with the maxillary central incisors. The treatment objectives were to create space for the impacted canines and align them with the incisors, one of which was extracted. After treatment, the appearance of the patient's teeth was improved, the occlusion was preserved, and overjet and overbite were corrected.

A estética no sistema de braquetes autoligáveis / The self-ligating system in an aesthetic view

INTRODUÇÃO: os braquetes autoligáveis foram, inicialmente, idealizados com objetivo de otimização do tempo de atendimento clínico. Por dispensar qualquer tipo de amarração, inúmeras vantagens foram atribuidas a este sistema, com a redução da fricção superficial na interface braquete/fio ortodôntico. Com esta redução, são necessárias forças de menor intensidade para o estabelecimento da movimentação dentária, realizada, assim, de uma forma mais rápida e eficiente. Em decorrência da maior demanda estética por parte dos pacientes, os braquetes autoligáveis começaram a ser confeccionados em policarbonato, promovendo ganhos estéticos únicos, quando em comparação a seus anólogos metálicos. OBJETIVO: realizar uma revisão de literatura sobre o sistema de braquetes autoligáveis estéticos.

INTRODUCTION: The self-ligating system was introduced aiming the reduction of chair time. Once this system does not need any ligation form, several advantages were observed, such as the reduction on superficial friction in couple bracket/ orthodontic wire, and the reduction on the force level that is necessary to establish the orthodontic tooth movement. The growing demands of aesthetic patients induced the self-ligating system to be made of polycarbonate material, resulting in unique aesthetic advantages when compared with the metallic form of this system. AIM: The objective of this paper was to proceed with a literature review about aesthetic self-ligating brackets.