Influence of additional polymerization for experimental composite in indirect restoration technique

• Grant number: 14/07641-4
• Support type: Scholarships in Brazil - Scientific Initiation
• Effective date (Start): July 01, 2014
• Effective date (End): December 31, 2015
• Field of knowledge: Health Sciences - Dentistry - Pediatric Dentistry
• Principal researcher: Fernanda Miori Pascon
• Grantee: Bruna Camargo Carrasco
• Home Institution: Faculdade de Odontologia de Piracicaba (FOP). Universidade Estadual de Campinas (UNICAMP). Piracicaba , SP, Brazil

Abstract

The aim of this study is to evaluate the influence of different proportions of inorganic fillers and additional polymerization methods on the physical properties of experimental composites. For this, four experimental composites will be prepared containing 30 wt.% of organic matrix and 70 wt.% of filler in following proportions: only barium glass particles Ba-Al-Si (C1), barium glass Ba-Al-Si/silica SiO2 90:10 (C2), barium glass Ba-Al-Si/silica SiO2 80:20 (C3) and barium glass Ba-Al-Si/silica SiO2 70:30 (C4). Silicon matrices (5mm diameter x 2mm thick) will be fulfilled by experimental composites (C1 - C4) and photoactivated by Bluephase-G2 with standardized energy dose of 36J. Then, the specimens will be subdivided according to the protocol of post-polymerization: control (P0-without post- polymerization process); Beta Visio unit 470mW/cm2 for 15 minutes (P1); 200 ml water for 5 minutes in a microwave at 500W (P2). After, the specimens will be stored in deionized water at 37°C for 24h and subsequently polished with 600-, 800- and 1200- grit SiC papers and 3¼m and 1¼m diamond paste and cloth. The specimens will be placed in ultrasound (USC 1400-Unique, Santo Amaro, Brazil) for 20 minutes. The specimens will be analyzed concerning the conversion degree (Spectrum 100 FTIR/ATR, Perkin Elmer, MA, USA), roughness (Surftest 211-Mitutoyo, São Paulo, Brazil) and microhardness (HMV-2000, Shimadzu, Tokyo 101, Japan). The results will be submitted to the appropriate statistical tests at significance level of 5%.