Microtensile bond strength to ceramic of a experimental resin cement containig a Onium salt

Abstract

The aim of this study will be to evaluate the bond strength of experimental resin cements containing different concentrations of diphenyliodonium hexafluorphosphate onium salt in its formulation to a lithium disilicate reinforced ceramic by comparing the values with a dual resin cement Rely X ARC (3M ESPE, St Paul, MN). 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 used following the manufacturer's recommendations. The blocks will be made with 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. (AU)