Análise de superfícies dentinárias apicectomizadas com broca, LASER CO2 e LASER Er:YAG por meio de MEV e EDS

• Ano de defesa: 2008
• Autor(a) principal: Pereira, Ana Cláudia Lustosa
• Orientador(a): Oliveira, Marília Gerhardt de
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Pontifícia Universidade Católica do Rio Grande do Sul; Porto Alegre
• Palavras-chave em Português: ODONTOLOGIA; CIRURGIA BUCOMAXILOFACIAL; APICETOMIAS; LASER - ODONTOLOGIA; MICROSCOPIA ELETRÔNICA
• Link de acesso: http://hdl.handle.net/10923/545

Apicoectomy is a surgery in which the root apex is resected using slow- or high-speed burs. High power LASERs have been used as a technological alternative to perform resections. This in-vitro study evaluated resected surfaces to identify failures in the tooth/filling material interface (marginal adaptation) of the root canals and the chemical elements found on the sectioned surfaces of 24 apices of permanent human canines. Specimens were treated endodontically using posterior ablation with burs, CO2 or Er:YAG LASERs, and were divided in three groups: Br – apicoectomy at a 90-degree angle using burs and under constant irrigation with 0. 9% sodium chloride; CO2 – apicoectomy using CO2 LASER (5 W, CW/SP) without irrigation; Er – apicoectomy using Er:YAG LASER (400 mJ, 10 Hz) under constant air/water irrigation. Scanning electron microscopy images were obtained to evaluate resected surfaces, and EDS spectra, to identify minerals on each resected surface. To test variables for normality, the Shapiro-Wilk test was applied to the percentages of carbon, oxygen, magnesium, phosphorus and calcium found in dental apices of the three groups. ANOVA followed by the Tukey or the Games-Howell test was used for the normally distributed variables, and the Kruskal-Wallis test followed by the Dunn test, for nonnormal variables.The level of significance was set at 5%. Results showed that the surface of specimens resected with burs were less rough than those in the LASER groups. Surfaces that underwent apicoectomy with CO2 LASER showed severe carbonization, which might have probably resulted in a greater percentage of carbon in this group than in the others. The comparison between groups revealed that the CO2 LASER group had the worst marginal adaptation results and the largest failures in the tooth/filling material interface. Considering clinical practice, the bur group had the best results because surfaces were less rough in specimens that underwent apicoectomy with burs, and marginal adaptation of the filling material was better than in the other groups.