The lingual enamel morphology and bracket shear bond strength influenced by Nd:YAG laser and aluminum oxide sandblasting preconditioning.

OBJECTIVES: This study aimed to investigate the influence of Nd:YAG laser and aluminum oxide sandblasting on the shear bond strength (SBS) of lingual brackets and to optically analyze the behavior of the enamel morphology. MATERIALS AND METHODS: Thirty-five bovines' incisors teeth were divided into 5 groups (n = 7), according to the surface preconditioning: G1, control group; G2, Nd:YAG laser; G3, laser + aluminum oxide sandblasting (Al2O3); G4, Al2O3; and G5, Al2O3 + laser. All groups had lingual brackets bonded and shear debonded after 72 h. SBS values were analyzed, and the enamel morphology was evaluated by optical coherence tomography (OCT) and scanning electron microscope (SEM), before and after preconditioning surface. The optical attenuation coefficient (α) analysis was obtained from OCT images. Data analysis used the ANOVA test, followed by post hoc Tukey, Kruskal Wallis, and post hoc Dunn tests (significance of 5%). RESULTS: The SBS values presented similarly among groups, but the value of α showed statistical difference (p-value = 0.0124) between G3 and G5 with the others. Optical analyses indicated a melting on the enamel that suffered laser irradiation for G2 and G5 and crystal surface disorganization for G4. Sandblasting partially removes the melting of the laser effect (G3). CONCLUSION: The sandblasting is a dispensable step for bonding lingual brackets, and the melting of the enamel after laser irradiation does not compromise the bracket adhesive resistance. CLINICAL RELEVANCE: The Nd:YAG laser became an interesting tool to prevent caries and decrease prevalence of white spot lesions in orthodontic treatments, without systemic effects in patients with genetic high risks of caries.

A Ortodontia Lingual e a contribuição efetiva do corredor bucal na estética do sorriso ­ relato de caso / Lingual Orthodontics and the effective contribution of buccal corridor to the smile aesthetics ­ case report

Um sorriso atraente ajuda as pessoas a se sentirem mais confiantes e a parecerem mais jovens, podendo influenciar inclusive no desempenho das relações profissionais e pessoais, além de impactar no desenvolvimento da personalidade. Dentre as características estudadas e consideradas importantes para um sorriso estético, está o corredor bucal. Atributo que pode ser definido como a diferença entre a largura da dentição maxilar visível e a largura da comissura interna. A influência negativa da presença do corredor bucal excessivo sobre a estética do sorriso é um tema controverso e que abrange uma gama de trabalhos na literatura, podendo ser incluído na lista de problemas ortodônticos durante o diagnóstico e planejamento do tratamento. Considerando esse contexto, o presente trabalho tem o objetivo de relatar um caso clínico tratado com Ortodontia lingual, em que foram alcançados resultados estéticos favoráveis com a diminuição do corredor bucal.(AU)

An attractive smile helps people to feel more confident and look younger and could have influence on professional performance and personal relationships, as well as it may have impact on personality development. Among the characteristics studied and considered important for smile aesthetic is the buccal corridor. It can be defined as the difference between the width of the visible maxillary dentition and the width of the inner commissure. The negative influence of excessive buccal corridor presence in the smiling aesthetics is a controversial subject that is covered in a range of literature works; it can be included in the list of orthodontic problems during the diagnosis and treatment planning. Considering this context, the present work aims to report a clinical case treated with lingual orthodontics, in which favorable aesthetic results were obtained with reduction of the buccal corridor. (AU)

Aplicação clínica dos adesivos autocondicionantes / Clinical application of autocondicionantes adhesives

O sistema adesivo autocondicionante é, atualmente, utilizado em diversas situações dentro da Odontologia devido à sua eficácia inquestionável, relacionada tanto à sua boa resistência de união quanto ao seu modo de utilização, necessários a todos os procedimentos restauradores. Diantedas suas indicações, as restaurações em dentes posteriores caracterizam-se como uma das mais importantes relacionadas a essa atual tecnologia. É bem sabido que o estabelecimento de um correto diagnóstico e planejamento, bem como o conhecimento dos materiais que serão utilizados, são etapas fundamentais para o sucesso do tratamento. E, o uso do sistema adesivo autocondicionantes além de garantir as vantagens alcançadas pelos sistemas convencionais, permitindo menor desgaste de estrutura dental e minimizando os efeitos da contração de polimerização e, consequentemente infiltração marginal. também garante vantagens como uniformidade no padrão da superfície condicionada e diminuição do seu tempo de aplicação o que, leva a diminuição do tempo clínico do tratamento, aumentando o conforto do paciente.Assim, o presente trabalho tem o objetivo de discutir as possíveis vantagens e limitações da utilização de sistema adesivos autocondicionantes, de acordo com as possibilidades atualmente disponíveis para o restabelecimento da saúde e estética dos elementos dentais, conhecendo melhor estes materiais e suas aplicações dentro da Dentística.

The self-etch adhesive system use is, currently, enclose in a diversity of situations inside Dentistry because of its unquestioned effectivenes related both to their good resistance to union about its mode of use, necessary to all restorative procedures. Ahead of your indications, the restoration in posterior teeth are frequently appearing like one of the most important option for use of this actual technology. Well, it is known that the establishments of a correct diagnosis and planning, as well as the knowledge of the materials that will be used, are basic stages for the success of the treatment. And, the use of the self-etch adhesive system beyond guaranteeing the advantages reached for the conventional systems, allowing less wastage of the dental structure and minimizing the polymerization contraction effect and, consequently marginal infiltration, also guarantees advantages as uniformity in the pattern of conditional surface and reduction of its time of application, which leads to reduction in the time of clinical treatment, increasing the comfort of the patient. So, this work has the objective to discuss the possible advantages and limitations of the self-etch adhesive systems uses, agreeing with the currently available possibilities for the reestablishment of the health and dental elements aesthetic, better knowing these materials and its applications inside of the Dentistry.