Evaluation of the diametral tensile strength and microhardness of direct and indirect resin composites before and after storage in water

• Grant number: 10/01058-4
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: May 01, 2010
• End date: April 30, 2011
• Field of knowledge: Health Sciences - Dentistry - Dental Materials
• Principal Investigator: Laís Regiane da Silva Concilio
• Grantee: Paula Barbosa Alves
• Host Institution: Pró-Reitoria de Pesquisa e Pós-Graduação. Universidade de Taubaté (UNITAU). Taubaté , SP, Brazil

Abstract

The aim of present study will be to compare the mechanical properties of direct and indirect resin composites before and after storage in water. A total of 25 samples of each material (two direct and to indirect resin composites) will be confectioned. The initial measurement of Diametral tensile strength (DTS) will be performed using 10 samples of each restorative material. They will be submitted individually to an universal testing machine (Versat, model 2000), using crosshead speed of 1,0 mm/min. Initial Knoop microhardness will be measured in 5 samples of each group, using a Microhardness machine (HMV-2000), under load of 50 grams for 15 seconds. At the end of the initial analyses, ten new samples to DTS and the same 5 samples to microhardness will be stored at 37oC and 100% humidity for 10 months. At the end of the storage period, DTS and microhardness measurements will be performed, using same parameters of the initial analysis. The values obtained will be submitted to statistical evaluation, being analyzed at the level of 5% of significance.