Effect of photodynamic therapy on superficial demineralization of bovine enamel and root dentin in vitro

Abstract

Antimicrobial photodynamic therapy has been used in dentistry for bacterial elimination on root canal, periodontal pocket and treatment of periimplantitis. It is a safe technique, but we observed clinically a superficial demineralization on enamel and dentine hypersensitivity after its application on dental crowns. The aim of this study is to evaluate if photodynamic therapy with toluidine blue O causes superficial demineralization on bovine enamel and radicular dentin. Enamel and root dentin blocks will be divided in four groups: control (without treatment), photodynamic therapy (dye pH3), photodynamic therapy (dye pH5), citric acid (pH1). Laser used for photodynamic therapy will be red (660nm), 45J/cm², 30mW. Punctual mode associated to toluidine blue. Microhardness Knoop will be evaluated by a microhardness tester and surface profile of enamel and dentin will be obtained by a contact profilometer. The statistical analysis will be realized at a significance level of 5% (P<0,05). ANOVA test complemented by Tukey will be used if the sample presents normal distribution. If the distribution is not normal Kruskall-Wallis complemented by Dunn tests will be used. (AU)