Microtensile bond strength to a glass ceramic and properties of experimental resin...
| Grant number: | 11/21842-4 |
| Support type: | Regular Research Grants |
| Duration: | May 01, 2012 - April 30, 2014 |
| Field of knowledge: | Health Sciences - Dentistry - Dental Clinics |
| Principal Investigator: | Giselle Maria Marchi Baron |
| Grantee: | Giselle Maria Marchi Baron |
| Home Institution: | Faculdade de Odontologia de Piracicaba (FOP). Universidade Estadual de Campinas (UNICAMP). Piracicaba , SP, Brazil |
Abstract
The aim of this study will be to evaluate the bond strength of experimental resin cements containing different concentrations of diphenyliodonium salt in its formulation to a lithium disilicate reinforced ceramic and the influence of two tertiary amines (added in its formulation) on the properties of these same experimental cements. A model Bis-GMA/TEGDMA comonomer blend (1:1 molar ratio) was obtained and DPI added at concentrations of 0 (control), 0.25, 0.5, 1 and 2 mol% resulting in five experimental resin cements. The photoinitiator system was composed of 1 mol% of camphorquinone and 2 mol% of dimethylaminoethyl methacrylate. 0.1 mol% of hydroxyl butyl toluene was used as an inhibitor and the cements were loaded with a 60% mass fraction of silanated Ba-Al-Si glass fillers. Lithium disilicate ceramic (e.max, Ivoclar Vivadent, Schaan, Liechtenstein) rectangular blocks will be made following the manufacturer's recommendations measuring 3mm x 10 mm x 6 mm of high, wide and thick respectively in order to cure the cement through ceramic. A light-cured resin Filtek Supreme XT (3M ESPE) measuring 5 mm x 10 mm x 6 mm will be used as basis for the procedure and the blocks will be made with a polyvinyl siloxane matrix measuring 10 mm x 10 mm x 6 mm. After the microtensile test, it will be analyzed the pattern of fractures and the values will be tabulated and submited to an appropriate statistical test. Ethyl 4-dimethylamino benzoate EDMAB and dimethylaminoethyl methacrylate (DMAEMA) will be evaluated in the following concentrations: 0% DFI G1 with 0.5% DMAEMA, G2 0% 1% DMAEMA with DFI,% DFI with G3 0 0 5% EDMAB, G4 0% to 1% EDMAB DFI,% DFI 0.5 G5 with 0.5% DMAEMA, G6 0.5% to 1% DMAEMA DFI, DFI G7 0.5% to 0.5% EDMAB , G8 0.5% to 1% EDMAB DFI, DFI G9 1% to 0.5% DMAEMA, G10 1% 1% DFI with DMAEMA, G11 1% to 0.5% EDMAB DFI, DFI G12 1% 1% EDMAB. Each test will have a specimen size according to protocol. The specimens will be made to perform the following tests: degree of conversion (5 mm x 0,5 mm), flexural strength modulus(6,5mm × 2 mm × 1 mm), water sorption and solubility (6mm x 1 mm). The results will be statistically analyzed for each of the tests. (AU)