Effect of at-home bleaching with different thickeners on color change and microhardness in enamel

• Grant number: 16/17526-3
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: March 01, 2017
• End date: February 28, 2018
• Field of knowledge: Health Sciences - Dentistry - Dental Clinics
• Principal Investigator: Debora Alves Nunes Leite Lima
• Grantee: Rafael Cabello Pereira da Silva
• Host Institution: Faculdade de Odontologia de Piracicaba (FOP). Universidade Estadual de Campinas (UNICAMP). Piracicaba , SP, Brazil

Abstract

The aim of this in vitro study will be evaluate at-home bleaching effect containing different thickeners on color change and surface hardness of dental enamel. Seventy enamel blocks will be obtained from bovine teeth (5 x 5 x 3mm) and randomly distributed into 7 groups according as whitener/thickener treatment: Carbamide Peroxide 10% (10% CP) with carbopol (FGM- Whiteness Perfect), 10% CP with carbopol (manipulated), 10% CP with natrosol (manipulated -experimental), only carbopol gel, only natrosol gel, only 10% CP and no treatment. The microhardness of the initial and final surface will be determined by the average of 5 indentations Knoop, 100µm apart, with a load of 50g and time of 5 seconds in a microhardness tester (HMV-2000, Shimadzu). The color analysis will be performed before and after treatment with a reflectance spectrophotometer (Konica Minolta) based on the CIE L*a*b* system. The differences in the L*, a*, and b* values will be expressed in ”L, ”a and ”b. The color change will be evaluated by the ”E calculation. After an exploratory and descriptive analysis, data will be submitted to statistical analysis, considering the level of significance of 5%. (AU)