|Support type:||Scholarships in Brazil - Master|
|Effective date (Start):||September 01, 2017|
|Effective date (End):||August 31, 2019|
|Field of knowledge:||Health Sciences - Dentistry - Dental Materials|
|Principal Investigator:||André Luiz Fraga Briso|
|Grantee:||Ana Carolina Souza Barboza|
|Home Institution:||Faculdade de Odontologia (FOA). Universidade Estadual Paulista (UNESP). Campus de Araçatuba. Araçatuba , SP, Brazil|
The purpose of this project will be to investigate the bonding strength of resin restorations in dentin, as well as to analyze the nanohardness of the hybrid layer and the cohesive strength of the dentin collagen, after performing different bleaching techniques. Therefore, initially 75 previously selected bovine teeth will be randomly distributed in the following groups: GI- Without bleaching; GII - Physical bleaching with violet LED light and GIII - Bleaching gel based on hydrogen peroxide at 35%). Then, 45 teeth will be destined to the analysis of the chromatic alteration spectrometry of reflection, being later prepared, restored and sectioned in sticks. Half of the samples will be subjected to the bonding strength and nanoindentation tests of the hybrid layer, while the rest will undergo 10000 thermal cycles before the evaluations. The remaining 30 teeth will be used to analyze the cohesive strength of the collagen (n = 10) that will be performed immediately after the bleaching treatments, as well as after the collagenase action. The data obtained from the bonding strength, the nanohardness and the cohesive strength of the collagen will be submitted to statistical tests of normality and specific tests to verify the significance between the averages.