COMPARAÇÃO DO ATRITO IN VITRO EM BRAQUETES ESTÉTICOS CONVENCIONAIS E AUTOLIGADOS

• Autor(a) principal: Leal, Rodrigo Severo
• Data de Publicação: 2009
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Biblioteca Digital de Teses e Dissertações da METODISTA
• Texto Completo: http://tede.metodista.br/jspui/handle/tede/1270
• topic: Atrito; braquetes autoligados, mecânica de deslize; Friction, self-ligating bracket, sliding mechanics; CNPQ::CIENCIAS DA SAUDE::ODONTOLOGIA::ORTODONTIA

The aim of this in vitro study was to compare the friction resistances among conventional steel-ligated and self-ligating aesthetic brackets with different retangular stainless steel archwires sizes at zero and three degrees angulation. 120 brackets of 6 commercial brands (Gemini, Clarity conventional, Transcend, Inspire, Clarity self-ligating, Damon self-ligating) where tested, 20 brackets of each brand. Two brackets were glued on a metallic plate, with angulations of zero and three degrees between them. Retangular stainless steel archwires of 0.017 x 0.025 , 0.019 x 0.025 and 0.021 x 0.025 were tested on a "instron" universal essay machine. Variance analisys and Tukey tests (p<0,05) were run to compare brackets with different archwires sizes and angulation. The study demonstrated that at zero degree angulation the self-ligating brackets produced less friction in relation to convencional ligated bracket in all archwires sizes tested. Clarity self-ligating produces even less friction then aesthetic Damon, except with the 0.021 x 0.025 archwire, where both self-ligating brackets produced statisticly similar results. Inspire bracket had the least friction with 0.019 x0.025 and 0.021 x0.025 . Similar results were observed for the self-ligating brackets in relation to convencionals at three degrees angulation. Among the convencional steel-ligated brackets, Gemini, Clarity, Transcend and Inspire produced the higest friction resistances, in increasing order. In conclusion, the angulation between the brackets increases significatively the friction forces. Furthermore, the self-ligating brackets produces less friction in relation to conventional ligating brackets, and the Clarity self-ligating bracket produced less friction than aesthetic Damon, except with 0.021 x 0.025 archwire size.(AU)