Evaluation of the influence of the incremental technique on the cohesive strength of different composites.

• Grant number: 10/15403-5
• Support Opportunities: Regular Research Grants
• Start date: November 01, 2011
• End date: April 30, 2013
• Field of knowledge: Health Sciences - Dentistry - Dental Materials
• Principal Investigator: Michel Nicolau Youssef
• Grantee: Michel Nicolau Youssef
• Host Institution: Faculdade de Odontologia (FO). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Associated researchers: Milena Traversa Palazon

Abstract

The aim of this study is evaluate the influence of the incremental technique on the cohesive strength of different composites. A Teflon bipartite device that notches to a metalic magazine will be made to keep the halves in position during the preparation of the composite proof body. From this conic-shaped device with dimensions of 4mm at the base, 2mm of diameter at the interface and 8mm height, 150 specimens will be obtained, divided into 10 groups (n = 15). The following composites will be used: Filtek P90, 3M ESPE, St.Paul, MN, USA, and Filtek Z350 XT, 3M ESPE, St. Paul, MN, USA, both color A3, inserted in the bipartite Teflon device according to the incremental technique used. The resin will be inserted with a metallic palette in horizontal or oblique increments, according to the inclination given by the instrumental used, in 2mm- thick increments, or even inserted at a time, in a single 4mm-thick increment photopolimerized for 40 seconds, as to the manufacturer´s instruction. The specimens will be submitted to traction tests in order to assess the composites strength and the influence of the incremental technique used. Obtained data will be analysed as to their distribution, if normal, they will be submitted to Analysis of Variance (ANOVA), if differences occur between the averages, these will be submitted to the Test of Tukey, or if there is not normality, non-parametric tests with significance of 5% (p <0.05) can be performed. (AU)