In vitro/in vivo led Violeta and in vitro argon plasma analysis on color alteration, mineral content, morphology and safety of teeth bleaching

Abstract

The aim of this project in its first study is to evaluate the in vitro enamel color alteration, hydrogen peroxide intrapulp concentration and enamel morphology alteration after bleaching with a novel purple LED and argon plasma associated or not to peroxides. The second study will address mineral content alterations after enamel exposure to the same treatments. Moreover, the third study will clinically evaluate efficacy, safety and mineral content of teeth submitted to bleaching with violet LED assossiated or not with high-concentrated peroxide gels. Bovine incisors will be used in the in vitro studies that either will have the crown maintained to the color, intrapulp and morphology evaluation (n=90) or will be cut into blocks and selected to microhardness test and mineral content analysis. The two sort of specimens will be split into 9 treatment groups (n=10): 1) PC; 2) PH; %; 3) PC/LED; 4) PH/LED; 5) LED; 6) PC/PL 7) PH/PL; 8) PL; 9) C. Color analysis will be performed using the ”E calculation (color alteration before and after treatments measurements by means of a spectrophotometer). Furthermore, intrapulp penetration will be obtained by the optic density of the solutions collected from the pulp chamber as well as the mineral content will be evaluated by means of microscopic analysis (EDX and FT-RAMAN) and enamel microbiopsy. For the clinical study, 100 patients will be selected after analysis of inclusion/exclusion criteria and will be divided into 5 treatment groups (n=20): 1) PC; 2) PH; %; 3) PC/LED; 4) PH/LED; 5) LED. Color alteration, patients tooth sensitivity and enamel mineral content (by means of spectrophotometry, subjective pain scale and microbiopsy, respectively) will be evaluated. Finally, data will be submitted to exploratory analysis and the most adequate statistical test will be selected. (AU)