Remineralizing treatments effects on the microhardness of demineralized enamel

• Grant number: 11/21397-0
• Support type: Scholarships in Brazil - Scientific Initiation
• Effective date (Start): May 01, 2012
• Effective date (End): April 30, 2013
• Field of knowledge: Health Sciences - Dentistry
• Principal Investigator: Alessandra Marques Corrêa Afonso
• Grantee: Débora Silva Baldi
• Home Institution: Faculdade de Odontologia de Ribeirão Preto (FORP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil

Abstract

The aim of the present study will be to assess the in vitro efficacy of different remineralizing treatments through the surface microhardness analysis of treated enamel. Bovine teeth fragments of 4x4x2.5mm will be planned. The initial surface microhardness (SM) will be determined by 5 indentations of 25g for 10s. For the formation of artificial enamel caries the blocks were immersed in 32 mL buffer acetate solution (32 h). Next, the microhardness test will be again performed and the percentage of surface microhardness change (%SMC) will be calculated. Sixty specimens based on the average values of %SMC will be selected and randomly divided on 6 groups according to the treatment of demineralized enamel surface (n=10): no treatment, fluoridated varnish, acidulated fluor phosphate, CO2 laser + acidulated fluor phosphate, CCP-ACP and CCP-ACP + CO2 laser. After surface treatments, the specimens will be submitted to challenge with acid consisting of a 8-day immersion in demineralizing (2 h) and remineralizing solution (22 h). The final microhardness test (SM1) will be performed and enamel remineralization will be quantitatively evaluated by the calculus of the percentage of surface microhardness change. For the data analysis the percentage of surface microhardness test will be considered.