Evaluation of chemical composition of affected dentin after selective removal of carious lesion with er: YAG laser and biomodification with Camellia sinensis encapsulated into chitosan nanoparticles

Abstract

The use of bio modifiers after selective removal of the carious lesion has been studied in order to improve the properties of the demineralized dentin matrix. This study aims to evaluate in vitro the chemical composition of affected dentin after selective removal of the carious lesion with Er: YAG laser, followed by biomodification with an experimental compound of Camellia sinensis encapsulated into chitosan nanoparticles. The sample will be composed of 60 healthy human third molars. Dentin specimens will be submitted to the microbial model for producing caries-like lesions. Selective removal of caries lesions will be performed by the Er: YAG laser (250mJ / 4Hz) or bur at low-speed handpiece (conventional method). Teeth will be divided according to dentin biomodification: no biomodification (control), chitosan nanoparticles (NanoC), Camellia sinensis encapsulated into chitosan nanoparticles (NanoCsC) for 1 min. Afterward, dentin scrapings will be submitted to Fourier transform infrared spectroscopy analysis (FTIR, n = 10) to evaluate the absorption peaks of phosphate, carbonate, organic matrix bands and water. The selection of statistical tests will be based on the characteristics of the data set for each variable. The statistical inferences will be made considering the significance level of 5%.