Avaliação da influência de um gel a base de peróxido de hidrogênio a 35% sobre a rugosidade superficial de três resinas compostas fotopolimerizáveis de diferentes tamanhos médios de partículas

• Autor(a) principal: Moro, André Fábio Vasconcelos
• Data de Publicação: 2007
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Biblioteca Digital de Teses e Dissertações da UERJ
• Texto Completo: http://www.bdtd.uerj.br/handle/1/14176
• topic: Dental bleaching; Composite resins; Surface roughness; Clareamento dental; Resinas compostas; Rugosidade superficial; Odontologia Aspectos estéticos; Dentes - Clareamento; Aspereza de superfície (Odontologia); CNPQ::CIENCIAS DA SAUDE::ODONTOLOGIA

The bleaching has been in dentistry as the simplest, common and conservative way to return of the pattern of color desired by the patients. The bleaching consists in an attack on dental surface breaking pigments, which are long chains of carbon, causing molecular chains ever smaller until it can be eliminated by diffusion. Considering the practice daily, the bleaching agent contacts restorative materials, such as composite resins for example. This procedure can appoint the replacement of the resin in good clinical conditions due the difference in color between the cleared tooth and composite. But there are cases, for examples: posterior restoratives and maintenance of bleaching, in which color would not be decisive factor for a clinical intervention on the restoration. This study evaluated, through atomic force microscopy, the effect of a memorandum of an in office dental bleaching by hydrogen peroxide 35% on the surface roughness of three types of resins of different sizes of particles (micro-hybrid, microparticles and nanoparticles). Twenty four images of 5 X 5μm randomly selected and generated by atomic force microscopy, were statistically analyzed by ANOVA and the SNK test (p< 0.05). The analysis of topographies showed the microfilled resin with lower initial roughness (Rq: 19.22μm and Ra: 14.95μm) and final roughness (Rq: 28.66μm and Ra: 23.06μm), with the final roughness statistically similar to initial roughness of nanoparticles resin (Rq: 29.60 μm and Ra: 23.75μm). Followed the initial roughness of micro-hybrid resin (Rq: 35.45 μm and Ra: 26.22 μm) and the final roughness of nanoparticles resin (Rq: 40.22μm e Ra: 31.49μm). The final roughness of micro-hybrid resin had the highest roughness (Rq: 47.41 μm and Ra: 36.45 μm). An uniform and proportional increase of surface roughness of the three resins tested was found. A second stage of the study evaluated the same area of surface before and after the procedure simulator of bleaching and the result was the same, with the view of the affected localities.