Influence of accelerated aging on the fracture resistance of dental polymers

• Grant number: 12/11407-1
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: November 01, 2012
• End date: March 31, 2013
• Field of knowledge: Health Sciences - Dentistry - Dental Materials
• Principal Investigator: Andréa Cândido dos Reis
• Grantee: Fabio Santos Bottacin
• Host Institution: Faculdade de Odontologia de Ribeirão Preto (FORP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil

Abstract

This study will investigate the influence of accelerated aging on the compressive strength of four composite resins. Will be used for a nylon matrix making a total of 64 specimens with 8.0 mm in height and 4.0 mm wide, 16 of each of the resins: Filtek Supreme (3M), Charisma (Heraeus Kulzer), Filtek Z-250 (3M), and P-90 (3M). To prepare the samples used will be the incremental technique respecting the curing time specified by the manufacturer. After 24 hours, eight of the specimens of each material shall be submitted to a compression test in a universal testing machine (EMIC DL-2000) with load cell 2000Kgf and a speed of 0.05 mm/min. The remaining 8 specimens are submitted to accelerated aging in UV-C machine system Accelerated Aging to nonmetallic - ASTM G-53 for 192 hours, equivalent to about five years of clinical conditions in normal aging, and subsequently be subjected to a compressive test. Upon completion of the tests, the mean compressive strength readings for each body-of-evidence will be submitted to the Kolmogorov-Smirnov test (p> 0.05), ANOVA, and Tukey test (p <0.05). The software used for statistical analysis will be the NCSS 2007 (NCSS, Kaysville, USA.(AU)