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Objective: This pilot study concerned evaluation of the success of predicted dental changes in patients presenting with Class I malocclusions who were submitted to treatment aligners, using the superimposition. Methods: The digital models were superimposed and analyzed using 3DSlicer 5.0 software. Treatment and predicted changes regarding horizontal and vertical linear displacements, mesiodistal rotations, and incisor buccolingual tipping were quantified. The success rates were calculated by dividing the mean treatment change amount by the predicted change amount. Results: Lower-incisor intrusion was the most accurate of the predicted vertical displacements (86.96 %), and buccal expansion of upper canines (99.32 %) and mesial translation of the lower incisors (98.57 %) were the most accurate horizontal linear displacements. The predicted rotation was achieved with the highest accuracy for lower incisors (75.69 %). Incisor buccolingual tipping success rates ranged between 45.78 % and 69.31 %. Low accuracy of predicted changes was found for upper-molar extrusion (10.23 %) and constriction (8.91 %). However, minimal corrections in these directions were planned. Conclusions: Dental changes for all regions of maxillary and mandibular arches could be evaluated. High success rates were observed for most of the movements planned for ClearCorrect aligner therapy.

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BACKGROUND: This study aims to compare the impact of pain on quality of life and patient satisfaction during treatment with aligners. METHODS: Ninety-four subjects in active treatment were invited to answer self-reported questions concerning pain severity and duration, occurrence of other signs and symptoms, and level of satisfaction with their treatment. Also, the OHIP-14 questionnaire was applied to assess patients' OHRQoL. RESULTS: Ninety-four patients (49 women and 45 men) answered the survey. Pain duration of 1-3 days was reported by 69.1% of patients (n = 60). For those who reported pain (n = 84), it was considered mild severity by 42.9% and moderate by 52.4%. Almost sixty-four percent of the sample were very satisfied with the aligner's aesthetics (n = 60) and forty-nine percent were satisfied with treatment in general (n = 46). Mean OHIP-14 score was 3.36 ± 2.54. OHRQoL was significantly associated with pain severity, whereas patients who reported having experienced moderate pain presented a significantly higher mean OHIP-14 score than those who reported having experienced mild pain (3.92 ± 1.93 and 2.69 ± 2.83, respectively; p = 0.036). The "psychological discomfort" OHIP-14's domain was the most influenced by the level of pain. CONCLUSION: Pain severity significantly influenced OHRQoL, in adult patients under treatment with clear aligners. However, high levels of patient satisfaction were reported, regardless of pain duration or severity.

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Resumo A segunda mais prevalente má oclusão de Angle na população é a de Classe II. Dentre as abordagens de tratamento consideradas pelos profissionais, está a distalização dos dentes posteriores superiores ou exodontias. A distalização, dependendo do nível de complexidade do caso, pode ser desafiadora e necessitar de mecânicas auxiliares para realizar movimentos translacionais e não somente de inclinação coronária. A escolha da abordagem para esses tratamentos depende diretamente da colaboração do paciente, severidade da má oclusão, caracterização da Classe II, idade do paciente e habilidade técnica do profissional responsável. Com o aumento da procura por tratamentos ortodônticos mais estéticos, os alinhadores ortodônticos têm sido frequentemente uma alternativa aos pacientes. Dependendo da severidade da má oclusão, pode-se associar aos auxiliares comumente utilizados na Ortodontia convencional fixa. Portanto, o objetivo deste trabalho é apresentar a resolução de uma má oclusão de Classe II, divisão 1, com impactação do canino superior direito e desvio de linha média superior para a direita tratada com alinhadores ortodônticos ClearCorrect. (AU)

Abstract The second more prevalent Angle's malocclusion on the population is Class II. Among the continuously considered treatment approaches by clinicians, is the distalization of upper teeth or extractions. The distalizations, depending on the case's complexity, can be challenging and need auxiliary mechanics to perform translation movements and not just crown tipping. The choose of the appliance for these treatments relies directly on the option/collaboration of the patient, malocclusion severeness, patient's age, and technical ability of the main professional taking care of the case. With the crescent search for more aesthetic orthodontic treatments, the clear aligners have been frequently looked for by the patients as an alternative and, regularly related to auxiliaries commonly associated to the conventional fixed appliances. Regarding this context, the objective of this study is to present the case report of a patient with Class II, division 1, upper midline deviation to the right and unerupted upper right canine through the ClearCorrect aligners' system. (AU)

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Resumo O adequado planejamento e o tratamento precoce da má oclusão de Classe II de Angle, com atresia maxilar e mordida aberta anterior, proporciona a harmonização das bases ósseas maxilo-mandibulares nos três planos do espaço. Os alinhadores ortodônticos surgiram como uma alternativa de tratamento, tendo como vantagens: serem mais estéticos e mais confortáveis para o paciente, permitirem menor tempo de tratamento, quando corretamente indicados, menor tempo de cadeira, menos intercorrências, possibilidade de monitoramento à distância, maior facilidade de alimentação e higienização dentária. Por outro lado, apresentam dificuldades em tratamentos de adultos com más oclusões severas de Classe II esquelética, de mordida cruzada posterior e de mordida aberta anterior. Portanto se objetiva com esse relato de caso clínico corrigir precocemente a má oclusão de Classe II esquelética com atresia maxilar, por meio do uso de ortopedia mecânica e dispositivos que auxiliam na eliminação de hábitos e fechamento da mordida aberta anterior e, posteriormente, a utilização de alinhadores ortodônticos para a finalização do tratamento. Concluiu-se que o tratamento interceptativo precoce da má oclusão foi eficiente para a harmonização entre as bases ósseas nos sentidos ântero-posterior, vertical e transversal, transformando essa má oclusão de alta para baixa complexidade e, consequentemente, altamente previsível e com excelente prognóstico para o tratamento com alinhadores ortodônticos. O tratamento com os alinhadores ClearCorrect corrigiu a oclusão em um curto período de tempo, quando comparado com Ortodontia corretiva e com uma alta previsibilidade em relação ao setup virtual. (AU)

Abstract Adequate planning and early treatment of Angle Class II malocclusion with maxillary atresia and anterior open bite provides harmonization of maxillomandibular bone bases in the three planes of space. Orthodontic aligners have emerged as an alternative treatment having the following advantages: being more aesthetic and more comfortable for the patient, less treatment time when they are correctly indicated, less chairside time, less complications, possibility of remote monitoring, easier feeding, and dental hygiene. On the other hand, they offer difficulties to treat adults with severe skeletal Class II malocclusions, posterior crossbite and anterior open bite. Therefore, the objective of this clinical case report is to early correct skeletal Class II malocclusion with maxillary atresia through the use of mechanical orthopedics and devices that help eliminate habits and close the anterior open bite, and later the use of orthodontic aligners to finish the treatment. It was concluded that the early interceptive treatment of malocclusion was efficient to harmonize the bone bases in the anteroposterior, vertical, and transversal directions, changing this malocclusion from high to low complexity and, consequently, highly predictable and with an excellent prognosis for treatment with orthodontic aligners. The treatment with ClearCorrect aligners corrected the occlusion in a shorter period of time when compared to corrective orthodontics and with a high (AU)

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Resumo O objetivo deste trabalho foi abordar o planejamento e o tratamento de uma má oclusão de Classe II/2 tratada sem extrações, utilizando alinhadores transparentes. No tratamento dessa má oclusão é necessário considerar o grau de severidade, se é dentária ou esquelética (avaliar se acomete somente a maxila, somente a mandíbula ou ambas), se há ou não crescimento, a colaboração do paciente, dentre outros fatores. Atualmente, muitos pacientes que procuram o tratamento ortodôntico desejam utilizar aparelhos mais estéticos, principalmente aqueles que já utilizaram o aparelho fixo convencional. Dessa forma houve um grande incremento na demanda pelos alinhadores transparentes removíveis, proporcionando benefícios como estética, maior facilidade de higienização e menor tempo de tratamento. No presente caso clínico, procurou-se manter o bom relacionamento maxilo-mandibular, o perfil e o bom selamento labial. Para tanto foram utilizados os alinhadores da ClearCorrect®, optou-se por não extrair pré-molar e realizar a distalização sequencial do lado da má oclusão de Classe II, associando com elásticos intermaxilares de Classe II, desgastes interproximais (IPR) e attachments. Os resultados alcançados foram altamente satisfatórios, restabelecendo o bom engrenamento dos molares e caninos, as inclinações vestíbulo-linguais adequadas dos incisivos superiores e inferiores, o overjet, o overbite e a correção das linhas médias. Portanto se concluiu que o tratamento desse caso clínico com alinhadores foi relativamente rápido, tão eficiente quanto o tratamento com aparelho fixo convencional e atendeu às expectativas estéticas da paciente. (AU)

Abstract The aim of this research was to address the planning and treatment of a Class II/2 malocclusion treated without extractions, using orthodontic clear aligners. For this malocclusion treatment it is necessary to consider the severity degree, whether it is dental or skeletal (assess whether it affects only maxilla, mandible, or both), whether there is growth or not, patient collaboration, among other factors. Currently, many patients that search for orthodontic treatment seek more aesthetic appliances, mainly those who have already used the conventional fixed appliance. Thus, there was a great increase in the demand for removable clear aligners, since they provide benefits such as aesthetics, easier hygiene and shorter treatment time. In this case report, we tried to maintain good maxillomandibular relationship, the profile and good lip sealing. To do so, ClearCorrect® aligners were used, also it was chosen not to extract premolars and to perform a sequential distalization on the Class II malocclusion side, associated with Class II intermaxillary elastics, stripping (IPR) and atttachments. The results were highly satisfactory, restoring good molars and canines relationship, adequate upper and lower incisors buccolingual inclinations, overjet, overbite and middle line correction. Therefore, it was concluded that the treatment of this case with clear aligners was relatively quick, as efficient as the treatment with a conventional fixed appliance and met the patient's aesthetic expectations. (AU)

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PURPOSE: The objective of this systematic review was to assess the three-dimensional changes in bone tissue after immediate installation of a single implant in a fresh extraction socket in the anterior maxilla. METHODS: After defining a strategy, an electronic search was carried out using the databases PubMed, Embase, LILACS, Web of Science, Cochrane, and Scopus. In addition, the gray literature was also researched using Google Scholar and ProQuest. Two reviewers independently screened for eligible studies, assessed the methodological quality, and extracted the data. The inclusion criteria were observational studies and experimental studies that assessed bone response after the immediate installation of a single implant in a fresh extraction socket, immediately loaded or not, in the region between the maxillary canines. Studies were included in any language, with no publication date restrictions and with a minimum of 6 months of follow-up after the surgical procedure. RESULTS: From a total of 3272 articles, only 12 studies met the inclusion criteria and were selected for the review. Bone remodeling after immediate installation of a dental implant was assessed using standardized periapical radiographs and cone beam computed tomography (CBCT). CONCLUSION: It can be concluded that bone remodeling occurs after tooth extraction and immediate implant installation.

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O sorriso gengival é caracterizado pela exposição excessiva da gengiva ao sorrir. Esta alteração pode ser classificada em anterior, posterior, mista e assimétrica. Sua etiologia está associada a diversos fatores, tais como gengivais, esqueléticos e musculares. A toxina botulínica tipo A tem sido bastante utilizada na Odontologia para a correção do sorriso gengival, tendo como vantagem ser um procedimento pouco invasivo, seguro e eficaz. Esta pesquisa teve como objetivo avaliar, por meio de questionários, a satisfação dos pacientes em relação aos resultados obtidos com a aplicação da toxina botulínica tipo A para a correção do sorriso gengival. O questionário foi respondido antes da aplicação da toxina e 15 dias após. Participaram da pesquisa um total de 15 pacientes. Os resultados obtidos indicaram que os participantes classificaram seus sorrisos, após a aplicação da toxina botulínica, como muito bom e excelente. Todos os participantes da pesquisa relataram que ao sorrir não apresentavam exposição gengival e sentiam-se confortáveis durante o sorriso após a aplicação da toxina. Portanto, concluiu-se que os participantes da presente pesquisa apresentaram alto grau de satisfação com os resultados obtidos no tratamento do sorriso gengival com a aplicação da toxina botulínica tipo A (AU).

Gummy smile is characterized by gingival tissue excessive exposure while smiling. It can be classified as anterior, posterior, mixed, and asymmetric. Its etiology is associated with several factors, such as gingival, skeletal, and muscular. Botulinum toxin type A has been widely used in Dentistry for gingival smile correction with the advantage of being a less invasive, safe, and effective procedure. The purpose of this study was to investigate patient satisfaction in relation to the results obtained with botulinum toxin type A application for gummy smile correction using questionnaires. The questionnaire was answered before and after 15 days of the toxin application. A group of 15 patients participated of the study. The results showed that the participants classified their smiles, after the application of botulinum toxin, as very good and excellent. All study participants reported no more discomfort with gingival exposure when smiling and everyone felt comfortable with the smile after botulinum toxin application. Therefore, it was concluded that all participants were satisfied with the results obtained after botulinum toxin type A gummy smile treatment (AU).

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A expansão rápida da maxila osseossuportada tem sido amplamente utilizada na clínica ortodôntica, entretanto ainda existem dúvidas em relação ao planejamento e efeitos do tratamento. É objetivo do presente artigo relatar um caso clínico descrevendo passo a passo as etapas de planejamento, confecção e instalação do aparelho. Paciente com mordida cruzada posterior, 11 anos de idade foi indicada para tratamento com aparelho. Inicialmente, foi realizada tomografia computadorizada de feixe cônico a fim de planejar o local ideal de instalação de 4 mini-implantes considerando a disponibilidade óssea no palato. Imediatamente após a instalação dos mini-implantes foi realizada moldagem, adaptação de mini-implantes de latão no alginato e confeccionado modelo de trabalho. O disjuntor em acrílico, apoiado apenas nos mini-implantes, foi adaptado em boca e a paciente instruída a ativar o torno expansor » de volta pela manhã e a noite durante 14 dias. Após esse período nova tomografia foi realizada, assim como após o tempo de contenção de 4 meses. Mensurações nas tomografias mostraram expansão maxilar sem efeitos de vestibularização de molares. Após 4 meses foi observada leve redução da expansão esquelética e inclinação lingual dos dentes posteriores. Pode ser concluído que o tratamento foi bem sucedido, resultando em correção da mordida cruzada posterior sem efeitos colaterais nos dentes posteriores.(AU)

Rapid bone-borne maxillary expansion has been widely used in orthodontic clinic, however there are still some doubts about its planning and treatment effects. The aim of this paper is to report a case describing step-by-step planning, manufacturing and installation of the appliance. Patient with posterior crossbite, 11 years-old was indicated to treatment with this appliance. A cone bean computed tomography was achieved to plan the ideal site for installing 4 miniscrews, considering bone availability of the palatal area. Immediately after miniscrews insertion, an impression was taken and miniscrews were inserted in the alginate to obtain the cast model. The acrylic appliance, supported exclusively on miniscrews, was adapted and the patient instructed to activate » turn twice a day for 14 days. After this period a new tomography was obtained and also after a 4-month retention period. Tomography measurements showed maxillary expansion with no molars vestibularization. After 4 months there was a slight decrease on maxillary expansion and molars lingual tipping. It can be concluded that the treatment was successful with correction of the crossbite and no deleterious effects in the posterior teeth.(AU)

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BACKGROUND: Tooth bleaching is, today, one of the most widespread cosmetic treatments in dental practice,  so it is important to determine whether it can interfere with orthodontic bonding or not. AIM: The aim of this study was to assess the in vitro effects of 35% hydrogen peroxide bleaching agent on the shear bond strength of orthodontic brackets. MATERIALS AND METHODS: Forty-five upper bicuspids were divided into three groups (n = 15). In the control Group (C), the brackets were bonded without previous bleaching treatment. Group 1 (G1) was treated with 35% hydrogen peroxide bleaching agent 24 h before bracket bonding. Group 2 was also bleached, and the brackets were bonded after 30 days. The shear bond strength of the brackets was measured using an EMIC machine, and the results were analyzed by ANOVA. RESULTS: There were no statistically significant differences between the three groups (P > 0.05), with Group C showing a mean bond strength of 9.72 ± 2.63 MPa, G1 of 8.09 ± 2.63 MPa, and G2 of 11.15 ± 4.42 MPa. CONCLUSION: It was possible to conclude that 35% hydrogen peroxide bleaching agent does not affect the shear strength of orthodontic brackets bonded 24 h and 30 days after bleaching.

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O objetivo deste trabalho foi comparar a efetividade de dois dispositivos de ancoragem ortodôntica, nos movimentos de intrusão de molares superiores. Neste estudo clínico prospectivo, 12 indivíduos que necessitavam de intrusão de molares superiores receberam miniplacas e mini-implantes para proporcionar ancoragem esquelética temporária. Observaram-se os aspectos clínicos e os sintomas pós-operatórios, bem como a efetividade dos métodos. Houve a perda de uma miniplaca por infecção e de mini-implantes palatinos, por falta de higiene local. Os dois tipos de dispositivos de ancoragem se mostraram capazes de auxiliar o movimento ortodôntico de intrusão sem causar nenhum tipo de prejuízo aos pacientes.

The aim of this study was to compare the effectiveness of two orthodontic anchorage devices for upper molar intrusion. In this prospective clinical study, 12 subjects received miniplates and mini-implants to provide temporary skeletal anchorage. Clinical and postoperative symptoms were observed as well as the effectiveness of both methods. One miniplate and palatal mini-implants were lost due to lack of local hygiene. Both types of anchoring devices can help orthodontic intrusion movement without patient compromising.

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OBJECTIVE: Evaluation of the force system produced by four brands of b-Ti wires bent into an elaborate design. METHODS: A total of 40 T-loop springs (TLS) hand-bent from 0.017 x 0.025-in b-Ti were randomly divided into four groups according to wire brand: TMATM(G1), BETA FLEXYTM (G2), BETA III WIRETM (G3) and BETA CNATM (G4). Forces and moments were recorded by a moment transducer, coupled to a digital extensometer indicator adapted to a testing machine, every 0.5 mm of deactivation from 5 mm of the initial activation. The moment-to-force (MF) ratio, the overlapping of the vertical extensions of the TLSs and the load-deflection (LD) ratio were also calculated. To complement the results, the Young's module (YM) of each wire was determined by the slope of the load-deflection graph of a tensile test. The surface chemical composition was also evaluated by an energy dispersive X-ray fluorescence spectrometer. RESULTS: All groups, except for G2, produced similar force levels initially. G3 produced the highest LD rates and G1 and G4 had similar amounts of overlap of the vertical extensions of the TLSs in "neutral position". G1 and G3 delivered the highest levels of moments, and G2 and G3 produced the highest MF ratios. b-Ti wires from G3 produced the highest YM and all groups showed similar composition, except for G2. CONCLUSION: The four beta-titanium wires analyzed produced different force systems when used in a more elaborate design due to the fact that each wire responds differently to bends.

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Abstract Objective: Evaluation of the force system produced by four brands of b-Ti wires bent into an elaborate design. Methods: A total of 40 T-loop springs (TLS) hand-bent from 0.017 x 0.025-in b-Ti were randomly divided into four groups according to wire brand: TMATM(G1), BETA FLEXYTM (G2), BETA III WIRETM (G3) and BETA CNATM (G4). Forces and moments were recorded by a moment transducer, coupled to a digital extensometer indicator adapted to a testing machine, every 0.5 mm of deactivation from 5 mm of the initial activation. The moment-to-force (MF) ratio, the overlapping of the vertical extensions of the TLSs and the load-deflection (LD) ratio were also calculated. To complement the results, the Young's module (YM) of each wire was determined by the slope of the load-deflection graph of a tensile test. The surface chemical composition was also evaluated by an energy dispersive X-ray fluorescence spectrometer. Results: All groups, except for G2, produced similar force levels initially. G3 produced the highest LD rates and G1 and G4 had similar amounts of overlap of the vertical extensions of the TLSs in "neutral position". G1 and G3 delivered the highest levels of moments, and G2 and G3 produced the highest MF ratios. b-Ti wires from G3 produced the highest YM and all groups showed similar composition, except for G2. Conclusion: The four beta-titanium wires analyzed produced different force systems when used in a more elaborate design due to the fact that each wire responds differently to bends.

Resumo Objetivo: avaliar os sistemas de força produzidos por quatro marcas de fios de -Ti, dobrados em formas complexas. Métodos: quarenta molas T-Loop (TLS) dobradas à mão, confeccionadas a partir de fios de -Ti, calibre 0,017" x 0,025", foram aleatoriamente divididas em quatro grupos, de acordo com a marca do fio: TMA (G1), BETA FLEXY (G2), BETA III Wire (G3) e BETA CNA (G4). Forças e momentos foram registrados por um transdutor de momento - acoplado a um extensômetro digital, adaptado a uma máquina de ensaios -, a cada 0,5mm de desativação, a partir de 5mm da ativação inicial. A proporção momento-força (M/F), a sobreposição das extensões verticais das TLSs e a relação carga-deflexão (C/D) também foram calculadas. Para completar os resultados, o módulo de Young (MY) de cada fio foi determinado pelo declive no gráfico de carga-deflexão em um ensaio de tração. Ademais, a composição química da superfície foi avaliada por um espectrômetro de fluorescência de raios X por energia dispersiva. Resultados: todos os grupos, exceto o G2, produziram níveis de força semelhantes, inicialmente. O G3 produziu as maiores taxas de C/D, enquanto G1 e G4 tiveram quantidades similares de sobreposição das extensões verticais das TLSs em posição neutra. G1 e G3 geraram os mais altos níveis de momentos, enquanto G2 e G3 produziram os mais altos índices de M/F. Os fios -Ti do G3 produziram o maior MY, e todos os grupos apresentaram composição semelhante, exceto G2. Conclusão: os quatro fios de beta-titânio analisados produziram diferentes sistemas de forças, quando utilizados para formas mais complexas, devido ao fato de que cada fio responde de forma diversa à confecção de dobras.

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A verticalização de molares é um movimento frequente na clínica ortodôntica, no entanto, a maioria das mecânicas empregadas causa a extrusão do molar, gerando interferências oclusais, abertura de mordida e problemas periodontais. O propósito deste artigo é a resolução de um caso clínico de verticalização do segundo molar inferior e a apresentação e discussão do sistema de forças do cantilever duplo. As vantagens da técnica do arco segmentado utilizando cantileveres, associadas à ancoragem esquelética com mini-implante, foram abordadas no presente artigo como uma alternativa mecânica para obter maior controle das forças que atuam na verticalização do molar e redução dos efeitos indesejáveis gerados nos dentes adjacentes. Como consideração final, pode-se afirmar que a verticalização de dentes posteriores utilizando um sistema de forças estaticamente determinado, como o cantilever duplo associado à ancoragem esquelética temporária, mostrou-se uma opção de mecânica eficiente com excelente controle vertical.

Molar uprighting is a common movement in orthodontic practice, however, most of the applied mechanical cause molar extrusion, creating occlusal interferences, bite opening, and periodontal problems. The purpose of this paper is to present a case of a lower second molar uprighting and a discussion about force system with double cantilevers. The advantages of the segmented arch technique using cantilevers, associated with skeletal anchorage with mini-implants, were addressed in this article as a mechanical alternative to obtain greater control of the forces acting on the molar uprighting and reduction of the undesirable effects on the adjacent teeth. As a final consideration, it can be said that the uprighting of posterior teeth using a statically determined system of forces, as double cantilever associated with temporary skeletal anchorage, proved to be an efficient mechanical option with excellent vertical control.

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Objetivos: determinar se a quantidade da pré-carga influencia a resistência ao destorque do parafuso e pilar de duas peças com junção cone-morse indexada. Material e métodos: foram utilizados 60 análogos de implantes conexão tipo cone-morse de 11,5° com indexador hexagonal e 60 munhões universal cone-morse parafuso passante (4,5 mm de diâmetro, 2,5 mm de altura cinta de transmucoso e 4 mm de altura, não indexados), divididos em três grupos segundo o torque aplicado: 15 Ncm (G1); 20 Ncm (G2) e 25 Ncm (G3). A análise de variância fator único (Anova) e o teste LSD foram usados para as comparações entre os grupos (nível de significância 5%). Imagens em MEV foram realizadas na cabeça do parafuso e na chave de aplicação de torque. Resultados: os valores médios para os destorques dos parafusos foram: G1=17,48 Ncm, G2=21,16 Ncm e G3=26,42 Ncm, com diferencas estatisticamente significativas (p < 0,001) entre todos os grupos. Os valores médios para os destorques nos pilares foram: G1=15,17 Ncm, G2=19,58 Ncm e G3=21,64 Ncm, sendo (G1 e G2) e (G1 e G3) (p < 0,001); e G2 e G3 (p=0,02). Conclusão: 1) o aumento do torque no parafuso gerou valor médio aumentado do destorque em todos os grupos; 2) o aumento do torque gerou valor médio de destorque equivalente ao torque inicial dado para o G1 e G2, sendo este aumento menor no G3; 3) torques maiores do que os indicados pelo fabricante foram capazes de promover a deformação plástica na cabeça do parafuso após apertos repetidos

Objectives: to determine whether the applied preload influences on detorque resistance of abutment and abutment screw of a two-piece, indexed cone-morse taper connection. Material and methods: Sixty implant analogs (cone-morse taper=11,5 degrees) with internal hexagonal indexing and sixty cone morse universal abutments (4.5 mm diameter, 2.5 mm collar height, and 4 mm in height, non-indexed), were divided into three groups according to applied torques: 15 Ncm (G1); 20 Ncm (G2), and 25 Ncm (G3). The one-way Anova and LSD tests were used for comparisons among groups (at 5% level). Representative SEM images were obtained from screw heads and key drivers. Results: mean detorque abutment screw values were as follows: G1=17.48 Ncm, G2=21.16 Ncm, and G3=26.42 Ncm, with statistically significant differences (p < 0,001) among all tested groups. Also, the mean detorque abutment levels were: G1=15.17 Ncm, G2=19.58 Ncm, and G3=21.64 Ncm, being (G1 and G2); (G1 and G3) (p < 0.001); and G2 and G3 (p=0.02). Conclusion: 1) an increase on abutment screw torque level also increases detorque values for all groups; 2) an increase on abutment torque level provided detorque values proportional to that found in G1 and G2, being this lower for G3; 3) torque values higher than those preconized by the manufacturer lead to plastic deformation at screw heads after repeated tightening sequences

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Lower molar uprighting has been increasingly indicated in clinical orthodontics, mainly because of adult patients with rehabilitation needs. The aim of this study was to determine the success rate of miniscrew use for lower molar uprighting and to compare the use of direct and indirect anchorage. One hundred and eighty-one miniscrews were inserted in 102 rehabilitation patients, with a mean age of 42.24 years. In 71 patients, indirect anchorage was used (116 miniscrews); in the other 31 patients, direct anchorage was employed (65 miniscrews). The choice of direct or indirect anchorage was determined by the orthodontist according to the force system that would be used for the movement and the bone availability. The overall success rate for miniscrews was 90. 05%; 18 miniscrews failed, including 15 that were used as indirect anchorage and 3 that were used as direct anchorage. Considering the results of this study, it can be concluded that both direct and indirect anchorage can be successfully used for molar uprighting.

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OBJECTIVE: To determine the mechanical characteristics of teardrop loop with and without helix fabricated using different metal alloy compositions (stainless steel and beta-titanium), submitted to different intensities of bends preactivation (0° and 40°), and with different cross-sectional dimension of the wire used to build these loops (0.017 x 0.025-in and 0.019 x 0.025-in). METHODS: Eighty loops used to close spaces were submitted to mechanical tests. The magnitudes of horizontal force, the moment/force ratio, and the load/deflection ratio produced by the specimens were quantified. Loops were submitted to a total activation of 5.0 mm and the values were registered for each 1.0 mm of activation. For statistic data analysis, a analysis of variance was performed and a Tukey's Multiple Comparison test was used as supplement, considering a 5% level of significance. RESULTS: In general, teardrop loops with helix produced lower magnitudes of horizontal force and load/deflection ratio, and higher moment/force ratio than teardrop loops without helix. Among all analyzed variables, metal alloy composition presented greater influence in the horizontal force and in the load/deflection ratio. The moment/force ratio showed to be more influenced by the preactivation of loops for space closure.

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OBJECTIVE: To determine the mechanical characteristics of teardrop loop with and without helix fabricated using different metal alloy compositions (stainless steel and beta-titanium), submitted to different intensities of bends preactivation (0º and 40º), and with different cross-sectional dimension of the wire used to build these loops (0.017 x 0.025-in and 0.019 x 0.025-in). METHODS: Eighty loops used to close spaces were submitted to mechanical tests. The magnitudes of horizontal force, the moment/force ratio, and the load/deflection ratio produced by the specimens were quantified. Loops were submitted to a total activation of 5.0 mm and the values were registered for each 1.0 mm of activation. For statistic data analysis, a analysis of variance was performed and a Tukey's Multiple Comparison test was used as supplement, considering a 5% level of significance. RESULTS: In general, teardrop loops with helix produced lower magnitudes of horizontal force and load/deflection ratio, and higher moment/force ratio than teardrop loops without helix. Among all analyzed variables, metal alloy composition presented greater influence in the horizontal force and in the load/deflection ratio. The moment/force ratio showed to be more influenced by the preactivation of loops for space closure.

OBJETIVO: determinar as características mecânicas de alças em gota e em gota com helicoide, quando da incorporação de variações na liga metálica (aço inoxidável e beta-titânio), na intensidade de dobras de pré-ativação (0º e 40º) e na secção transversal do fio utilizado para a construção dessas alças (0,017" x 0,025" e 0,019" x 0,025"). MÉTODOS: foram submetidas ao ensaio mecânico 80 alças para fechamento de espaços, sendo quantificadas as magnitudes de força horizontal, proporção momento/força e relação carga/deflexão produzidas pelos corpos de prova. As alças foram submetidas a uma ativação total de 5,0mm, sendo registrados os valores a cada 1,0mm de ativação. No tratamento estatístico dos dados obtidos, foi realizada a análise de variância, sendo essa complementada pelo teste de comparações múltiplas de Tukey, considerando o nível de significância de 5%. RESULTADOS: de maneira geral, as alças em gota com helicoide produziram menores magnitudes de força horizontal e relação carga/deflexão e maiores valores de proporção momento/força do que as alças em gota. Dentre todas as variáveis analisadas, aquela que apresentou uma maior influência na força horizontal e na relação carga/deflexão produzidas pelas alças foi a liga metálica. Já a proporção momento/força mostrou ser influenciada em maior grau pela pré-ativação das alças de fechamento de espaços.

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Os dispositivos intrabucais convencionais de ancoragem nem sempre são capazes de oferecer grande eficiência e resultam em movimentações dentárias indesejadas que podem comprometer o resultado final ou aumentar o tempo total de tratamento. A utilização de sistemas de ancoragem esquelética representa atualmente uma importante ferramenta na estratégia do tratamento ortodôntico por fornecer ancoragem estacionária, minimizando os efeitos indesejáveis em vários movimentos dentários e sem necessitar da cooperação dos pacientes. Neste relato de caso clínico é abordada a correção de má oclusão de Classe II subdivisão esquerda de Angle, com mecânica de distalização de molares por meio de Helical Bulbous Loop e com a utilização de mini-implantes para ancoragem. O objetivo do tratamento foi plenamente alcançado e, tanto as distalizações dos molares quanto o fechamento de espaço, foram ancorados em mini-implantes. Nenhum efeito colateral foi verificado durante o tratamento decorrente da ancoragem.

Conventional intraoral skeletal devices are not always efficient since they may cause undesirable dental movement that can compromise the final results and prolong the period of treatment. The use of skeletal anchorage systems represents an excellent tool for orthodontic treatment as it generates a stationary anchorage, with minimum unexpected dental movement and does not depend on patient compliance. The present study reports a clinical case of Angle Class II/2 malocclusion (subdivision left) treated with molars distalization using a Helical Bulbous Loop with the aid of iniscrews for anchorage. The aim of the treatment was fully achieved and both the distalization of molars and space closure were obtained through miniscrew anchorage. No side effect of anchorage was observed during treatment.

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OBJECTIVE: This in vitro study was designed to evaluate the shear bond strength (SBS) of orthodontic metal brackets bonded by direct and indirect techniques. METHODS: Thirty healthy human maxillary premolar teeth were used. The teeth were divided into three groups of 10 teeth each: Group I - indirect bonding with SondhiTM Rapid-Set system (3M/Unitek), Group II - indirect bonding with TransbondTM XT adhesive system (3M/Unitek) and Group III - direct bonding with TransbondTM XT adhesive system (3M/Unitek). After bonding and obtaining the specimens for the study, the specimens were subjected to SBS testing in a universal testing machine (Emic, model DL-500). The Kolmogorov-Smirnov test was applied to ascertain that the data had a normal distribution and the Bartlett test to check whether there was homogeneity of variance. One-factor analysis of variance was performed and, subsequently, Tukey's test for paired means. A 5% significance level was adopted. RESULTS: The results of Group I were 67.6 (N) and 5.9 (MPa); Group II, 68.9 (N) and 6.1 (MPa) and Group III (control), 92.5 (N) and 8.1 (MPa). CONCLUSION: It can therefore be concluded that the means for Group III were significantly higher compared with Groups I and II in both Newton (N) and Megapascal (MPa) values. The means attained by the indirect bonding technique used in Groups I and II, however, exhibited no statistically significant differences.

OBJETIVO: objetivou-se com esse trabalho avaliar, em um estudo realizado in vitro, a resistência ao cisalhamento de braquetes metálicos ortodônticos colados pelas técnicas direta e indireta. MÉTODOS: foram utilizados 30 dentes pré-molares superiores humanos hígidos. Os dentes foram divididos em três grupos de 10 dentes: Grupo I - colagem indireta com sistema Sondhi Rapid-Set (3M/Unitek); Grupo II - colagem indireta com sistema Transbond XT (3M/Unitek); e Grupo III - colagem direta com sistema Transbond XT (3M/Unitek). Após realização das colagens e confecção dos corpos de prova, esses foram submetidos ao teste de cisalhamento em uma máquina universal de ensaios da marca comercial EMIC, modelo DL-500. Foram aplicados os testes de Kolmogorov-Smirnov, para verificar se os dados tinham uma distribuição normal, e o teste de Bartlett, para verificar se existia igualdade entre as variâncias. Aplicou-se a análise de variância de um fator e, posteriormente, o teste de Tukey para o contraste pareado de médias. O nível de significância foi de 5%. RESULTADOS: os resultados do Grupo I foram 67,6N e 5,9MPa; do Grupo II foram 68,9N e 6,1MPa; e do Grupo III (controle), 92,5N e 8,1MPa. CONCLUSÃO: pode-se concluir que tanto para os valores em Newtons (N) como para os valores em Megapascal (MPa), a média do Grupo III foi significativamente maior em relação aos Grupos I e II. Já para as médias onde a técnica indireta foi usada (Grupos I e II), não houve diferenças estatisticamente significativas.

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OBJECTIVE: To evaluate changes in intercanine (LICW and UICW) and intermolar (LIMW and UIMW) widths on the dental arches of subjects with normal occlusion and Angle Class I malocclusion during the transition to permanent dentition, and evaluate whether or not facial pattern influences on the normal development of the dentition and occlusion. METHODS: Nineteen Caucasian Brazilian children were selected, with ages ranging from 6 to 8.6 years at T1 and from 10.10 to 14.2 years at T2. Their second records consisted of study dental casts and a lateral cephalometric radiograph. To obtain intermolar and intercanine widths a three-dimensional scanner unit (digitizer MicroScribe 3DX) was used connected to a microcomputer. To analyze changes at T1 and T2 Student's paired t-test was applied, whereas Spearman's correlation analysis was used to assess the relationship between measurements obtained at T1 and T2 and the facial pattern, both at 95% level of confidence. RESULTS: The mean values found on each assessment time (T1 and T2) were statistically different (p=0.000 for LICW, p=0.001 for UICW, p=0.000 for UIMW, and p=0.046 for LIMW), regardless of the facial pattern. The anterior dimensions, UICW and LICW, increased by 3.21 mm and 1.52 mm, respectively. And the posterior dimensions, UIMW and LIMW, increased by 2.16 mm and 0.50 mm, respectively. Only UIMW showed a significant correlation with the facial pattern (p<0.01). CONCLUSION: There was an increase in dental arch width during the transition period from primary or mixed dentition to permanent dentition irrespective of facial pattern. Only the changes observed in the maxillary intermolar width were associated with the facial pattern.