Effects of laser with calcium phosphate on permeability and bond strength in human dentin

Abstract

The objective of this study is to evaluate in vitro the effect of the use of calcium phosphate and application of laser in the permeability of human dentin and bond strength, modifying the application technique of the universal adhesive system for the purpose of forming a dentine with permeability reduced. Dentine discs will be used with approximately 6mm in diameter and 1,5 mm height, obtained from healthy human molars. Dentin permeability is measured in four stages: initial, maximum, during treatment and after treatment. After specimens standarization (n = 40) will be divided into two groups with (CFC) and without (SFC) the application of calcium phosphate and then will again be divided into two subgroups, resulting in 4 subgroups (n = 10):, AL- Adhesive + Laser, FAL- Calcium phosphate +Adhesive + Laser, LAL- Laser + adhesive + Laser, FLAL- Calcium phosphate + Laser + Adhesive +Laser. The application of Nd: YAG laser with energy of 60 mJ is without contact. Will use the Single Bond Universal (3M-ESPE) and after curing will be prepared cones Filtek Z 350 XT (3M ESPE) ofapproximately 1mm in diameter. The specimens will be submitted to 1000 thermal cycles, and later will be used microtensile test. Data from both evaluations will be submitted to ANOVA and Tukey's test (± = 5%). In addition they will be observed in scanning electron microscopy (SEM). (AU)