Influence of the type of thickening agent and viscosity of bleaching gel on hydrogen peroxide penetration through the tooth structure

• Grant number: 17/26560-3
• Support type: Scholarships in Brazil - Scientific Initiation
• Effective date (Start): May 01, 2018
• Effective date (End): April 30, 2019
• Field of knowledge: Health Sciences - Dentistry
• Principal researcher: Carlos Rocha Gomes Torres
• Grantee: Letícia Fernanda Cornélio
• Home Institution: Instituto de Ciência e Tecnologia (ICT). Universidade Estadual Paulista (UNESP). Campus de São José dos Campos. São José dos Campos , SP, Brazil

Abstract

The aim of this study will be to evaluate the influence of the type of thickening agent and the viscosity of 35% hydrogen peroxide gels on the peroxide penetration through the tooth structure. 130 bovine incisors will be used, from which enamel/dentin disks will be obtained from the labial surface, with 6mm of diameter and 2mm of thickness (1mm of enamel and 1mm of dentin). Experimental bleaching gels will be prepared containing four different types of thickening agents (Ar - Aristoflex - Clariant, Be - Bentonita - Casquímica, Ca - Carbopol 980 - Lubrizol e Sa - Salcare - BASF), which will be added in sufficient amount to produce gels with different viscosities: low (L - 30.000 cP), medium (M - 100.000 cP) and high (H- 250.000 cP). The specimens will be divided into the following groups (n = 10): PC (Positive Control) - a peroxide solution without addition of thickening agent will be applied, Ar/L - A low viscosity peroxide gel will be prepared with the Aristoflex thickener; Ar/M - medium viscosity with Aristoflex; Ar/H - high viscosity with Aristoflex; Be/L - A low viscosity gel will be prepared with Bentonite thickener; Be/M - medium viscosity with Bentonite; Be/H - high viscosity with Bentonite; Ca/L - A low viscosity gel will be prepared with the Carbopol thickener; Ca/M - medium viscosity with Carbopol ; Ca/H - high viscosity with Carbopol; Sa/L - A low viscosity gel will be prepared with the Salcare thickener; Sa/M - medium viscosity with Salcare; Sa/H - high viscosity with Salcare. Bleaching agents will be applied to the enamel surface for 45 minutes. The amount of peroxide that passes through the samples will be determined by spectrophotometry. The obtained data will be statistically analyzed adopting a significance level of 5%. (AU)