Impact of incorporated gases on the biofilm formation and properties of experimental methacrylate-based resins

• Grant number: 14/17878-1
• Support Opportunities: Regular Research Grants
• Start date: November 01, 2014
• End date: November 30, 2016
• Field of knowledge: Health Sciences - Dentistry - Dental Materials
• Principal Investigator: Flávia Pires Rodrigues
• Grantee: Flávia Pires Rodrigues
• Host Institution: Vice-Reitoria de Pesquisa e Pós-Graduação. Universidade Paulista (UNIP). São Paulo , SP, Brazil
• Associated researchers: Maristela Dutra Correa Bomfim

Abstract

This study aims to evaluate the impact of the incorporation of gases in biofilm formation and properties of methacrylate -based resins . Experimental resins controlled by the ratio based monomer (Bis -GMA ) and diluent ( TEGDMA ) by weight resin and a flowable resin-composite will be obtained and divided into six groups according to the experimental condition : G1- N'Durance Flow ( Septodont , USA ) - O2 , G2 - N'Durance Flow ( Septodont , USA ) - 24 in He , G3 - 60 % Bis - GMA and 40% TEGDMA - O2 ; G4 - 60 % Bis - GMA and 40% TEGDMA - 24 in He ; G5 - 40 % Bis - GMA and 60% TEGDMA and G6 - O2 - 40 % Bis - GMA and 60% TEGDMA - 24 in He , being or not degassed in Helium or stored in na Oxygen environment. The photoinitiator camphorquinone (CQ ) will be used at 0.2 % by weight and 2- dimethylaminoethyl methacrylate (DMAEMA) as co-initiator at 0.8% in the formulation of the experimental resins. Two groups of resins that have been pre- degassed in a controlled atmosphere that allows the Helium and Oxygen to be isolated, and the moisture is also controlled, were used to manufacture 'degassed' samples G2 , G4 and G6 . All samples will be cured with a calibrated light curing unit ( Bluephase , Ivoclar , Germany ). Initially, the mechanical properties of flexural strength and hardness as well as features of polymerization shrinkage, degree of conversion, polymerization depth , and density will be evaluate. Secondly, the biofilm adhesion test will be performed . Images of scanning electron microscopy for the morphological characterization of the samples, as well as fractural images of flexural tests Will be performed . The results of all steps will be undergoing isolated statistical analysis for each parameter and then be evaluated possible correlations between these parameters . The tests to be used will be chosen when the results are subjected to normality tests. (AU)