Preliminar study of a sodium trimetaphosphate-silver nanocomposite: analysis of the enamel remineralization and microbial adhesion on the bovine enamel

• Grant number: 12/17427-4
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Effective date (Start): February 01, 2013
• Effective date (End): December 31, 2013
• Field of knowledge: Health Sciences - Dentistry - Dental Materials
• Principal Investigator: Debora Barros Barbosa
• Grantee: Simone Carrijo Damante
• Host Institution: Faculdade de Odontologia (FOA). Universidade Estadual Paulista (UNESP). Campus de Araçatuba. Araçatuba , SP, Brazil

Abstract

The aim of this study will be to propose the synthesis of two nanocomposites based on sodium trimetaphosphate (nTMP) and silver(nAg) and evaluate its activity in adherence of Candida albicans an Streptococcus mutans and remineralization of bovine enamel. Colloidal silver nanoparticles of 10 nm average size, will be synthesized by reduction of the silver nitrate through sodium citrate. Then nTMP will be synthesized by grinding conventional particles of TMP. These two compounds will be associated with different synthesis procedures, yielding the nanocomposite in a liquid form (NAG / NTMP-I) and added to a photopolymerizable resin. (NAG / NTMP-II). The microorganisms will grow on surfaces of bovine enamel blocks in the artificial saliva in 96 microtiter plate wells for 2 hours (initial phase of biofilm adhesion) at 37°C under agitation of 120 rpm. The nAg/nTMP-I will be diluted in RMPI 1640 culture medium and BHI respectively to C. albicans and S. mutans for the treatment of biofilms for 24 hours. The enamel blocks will be then sonicated to release the adhered cells and to allow the quantification of viable cells (CFU). The extracellular matrix of the biofilm will also be quantified by staining crystal violet (CV). The activity of both nanocomposites on the remineralization process will be evaluated by means of Knoop hardness of the surface and longitudinal enamel blocks after the cariogenic challenge. The data will be analyzed using the most appropriate statistical test after the normality test is performed to verify adherence data to the normal curve. An appropriate posthoc test will be applied for each outcome. The significance level for all tests will be of 5%.(AU)