Análise da superfície dentinária radicular seccionada com broca e laser Er:YAG e fusionada com laser Nd:YAG por meio de MEV e EDS

• Ano de defesa: 2010
• Autor(a) principal: Farret, Alessandro Marchiori
• Orientador(a): Weber, João Batista Blessmann
• Tipo de documento: Dissertação
• 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/10923/456

The aim of this study was to evaluate the dentine surface of 20 lower bovine incisors which were undergone to root section with high-speed bur or Er:YAG laser, also using laser fusion of dentine by Nd:YAG laser. The teeth were assigned in two groups. In the first group the teeth were sectioned with high-speed bur with constant refrigeration and in the second group the teeth were sectioned with Er:YAG laser in the pulse mode, with 10 Hz of frequency and pulse energy of 500 mj (5 W of potency) under constant refrigeration with spray water/air from 3 mm of the tooth. Both methods of cut performed two surfaces, one of them was fused by Nd:YAG laser and the another one was kept without surface treatment. Through the Scanning Electron Microscopy (SEM), were done images of the surfaces and through the Energy Dispersion Spectroscopy (EDS) were obtained data about the molecular constitution of the remaining surfaces. For the comparison among the 4 groups the non-parametric test of Kruskal-Wallis was used. The results were considered significant at a maximum significance level of 5%. The group cut with bur without dentine fusion showed significant higher values of carbon in comparison with other groups.The group in which the teeth were sectioned by bur without surface treatment showed significant lower amounts of phosphorus in comparison with all other groups, followed by group where there was cut with bur and fusion by Nd:YAG and cut with Er:YAG and fusion by Nd:YAG, which did not differ between them. In the group with section by Er:YAG laser and without dentine treatment, were observed values of phosphorus significantly higher. The conclusion was that the cut surfaces with high-speed bur showed a smoother surface than the surfaces obtained with Er:YAG laser, visualized through the MEV analyses. Moreover, those same surfaces also showed lower amount of open dentine tubules, indicating that the method of section with bur could reduce the permeability of the dentine in comparison with Er:YAG laser even with the fusion by the Nd:YAG laser.