published_or_final_version / Paediatric Dentistry / Master / Master of Dental Surgery

Thesis supervisor: Saulo Geraldeli. Includes bibliographic references (p. 66-70).

Thesis (M.S.)--University of Louisville, 2004. / School of Dentistry, Program in Oral Biology. Vita. "May 2004." Includes bibliographical references (leaves 29-31).

published_or_final_version / abstract / Dentistry / Doctoral / Doctor of Philosophy

Thesis (Ph. D.)--University of Hong Kong, 2006. / Title proper from title frame. Also available in printed format.

Thesis (M.Sc.(Odontology))--University of Pretoria, 2009. / Includes bibliographical references (leaves 75-101).

Thesis (Ph. D.)--University of Missouri-Columbia, 1995. / Typescript. Vita. Includes bibliographical references (leaves 108-117). Also available on the Internet.

Thesis (Ph. D.)--University of Missouri-Columbia, 1995. / Typescript. Vita. Includes bibliographical references (leaves 108-117). Also available on the Internet.

nÃo hà / Preparos cavitÃrios dentÃrios confeccionados com laser de Er:YAG podem resultar em uma maior conservaÃÃo de tecidos sadios, maior abertura dos tÃbulos dentinÃrios sem presenÃa de lama dentinÃria, menor nÃmero de microrganismos na cavidade, alÃm de menor sensibilidade dolorosa durante sua confecÃÃo. Considerando que a irradiaÃÃo a laser pode diminuir a resistÃncia de uniÃo de materiais restauradores à dentina, esse estudo analisou o efeito da viscosidade de um sistema adesivo de condicionamento total de dois passos, em dentina irradiada com laser de Er:YAG. A dentina preparada foi testada em 2 tipos de preparo de superfÃcie (ponta diamantada e laser de Er:YAG) e a viscosidade do adesivo em 3 diferentes diluiÃÃes (Adperâ Single Bond 2 [SB], SB+10% e SB+20% de etanol). Sessenta terceiros molares humanos foram cortados e polidos, expondo superfÃcies de dentina oclusal. Foi utilizado o sistema adesivo SB para preparar as formulaÃÃes com diferentes viscosidades. As superfÃcies de dentina foram condicionadas com Ãcido fosfÃrico e os adesivos foram aplicados de acordo com as instruÃÃes do fabricante. PlatÃs de resina composta (Filtekâ Z250 XT) de 5 mm foram confeccionados. Os dentes preparados foram estocados em Ãgua destilada (37ÂC) por 24 h. Os espÃcimes foram seccionados em palitos de cerca de 1 mm de Ãrea transversal, os quais foram submetidos ao teste de microtraÃÃo. Propriedades fÃsico-mecÃnicas como Ãngulo de contato, taxa de evaporaÃÃo, grau de conversÃo, sorÃÃo/solubilidade de Ãgua e viscosidade dos adesivos foram definidas. Todos os resultados foram analisados com Two-way ANOVA e teste de comparaÃÃes mÃltiplas de Tukey (α=0.05). NÃo houve diferenÃa estatÃstica entre os valores de microtraÃÃo para todos os grupos. Os nÃveis de viscosidade nÃo afetaram a resistÃncia de uniÃo da dentina irradiada com laser de Er:YAG ou tratada com ponta diamantada. / Dental cavities prepared with Er:YAG laser may result in greater conservation of sound tissue, further opening of dentinal tubules without the presence of smear layer, few microorganisms in the cavity, and lower pain sensitivity during operative procedure. Whereas laser irradiation may decrease the bond strength of resin materials to dentin, this study examined the effect of viscosity of a two-step total-etch adhesive system on the bonding to dentin irradiated with Er:YAG laser. The prepared dentin was tested in 2 types of surface preparation (diamond tip and Er:YAG laser) and the viscosity of the adhesive at 3 different dilutions (Adperâ Single Bond 2 [SB], SB+10% e SB+20% de ethanol). Sixty human third molars were sectioned and polished, exposing dentin occlusal surfaces. SB adhesive system was used to prepare formulations with different viscosities. The dentin surfaces were acid etched and the adhesives were applied according to the manufacturer's instructions. Composite resin buildups (Filtekâ Z250 XT) of 5 mm were made. Prepared teeth were stored in distilled water (37oC) for 24 h. Specimens were sectioned into sticks (1 mm of cross sectional area), which were submitted to microtensile test. Physical-mechanical properties, such as contact angle, evaporation rate, degree of conversion, sorption/solubility of water and viscosity of the adhesives were defined. All results were compared with Two-way ANOVA and Tukey multiple comparison test (α=0.05). There was no statistical difference between the values of microtensile for all groups. The viscosity levels did not affect the bond strength of dentin treated either with Er:YAG laser or diamond bur.

published_or_final_version / Dentistry / Master / Master of Dental Surgery