ABSTRACT
A literature review on the existing information about bonding of orthodontic brackets on altered enamel surfaces, the influence of such surfaces on adhesion, and the most favorable conditions for achieving better bond strength is presented. Studies on bracket adhesion have identified the conditions that lead to morphological changes in enamel as dental fluorosis and dental bleaching. In this review, each of these conditions that alter the enamel surface and pose a major challenge to clinical orthodontists performing bracket bonding, will be analyzed. The literature provides a range of approaches for overcoming the challenges of bonding on altered enamel surfaces and will be discussed, taking into account, where possible, the type of adhesive selected. Adhesion on enamel that is fluorosed depends on the degree of severity and the bond strength on a bleached enamel surface depends largely on the concentration of the bleaching agent.
ABSTRACT
O estudo avaliou, longitudinalmente, o complexo maxilomandibular no sentido ântero-posterior de 24 pacientes do sexo masculino, tratados ortodonticamente com extraçöes de quatro pré-molares. As medidas cefalométricas empregadas säo algumas das que definem o padräo facial (SNA,SNB,ANB,SND e P-NB). A amostra constou de 72 telerradiografias em norma lateral, obtida ao final, 5 e 10 anos após o término do tratamento ortodôntico. As idades médias correspondiam a 15 anos e 6 meses, 19 anos 5 meses e 26 anos e 8 meses, respectivamente. No início do tratamento, 12 pacientes apresentavam má oclusäo de Classe I (grupoI e 12, de Classe II, 1ª Divisäo (grupoII). Os resultados demostraram que: 1) Na relaçäo da maxila com a base do crânio, expressa pela medida SNA; 2) Na relaçäo da mandíbula com a base do crânio, expressa pelas medidas SNB e SND; 3) Na relaçäo da maxila com a mandíbula, expressa pela medida ANB; 4) Avaliaçäo da medida linear P-NB