Effect Of Adhesive Application Protocols On Bond Strength Of Ceramic Veneer Thickness

Abstract

Aim: The aim of this study is to evaluate Shear Bond Strength of lithium disilicate ceramic veneers usingthree adhesive application protocols (pre-curing, co-curing and no adhesive application) using two resin cements (light cure total etch and dual cure self-etch). Material and Methods: By using CAD/CAM milling machine, 42 ceramic disc samples of dimensions 4X 4 mm in diameter and 0.5mm in thickness from Lithium disilicate ceramic material (Up-cad blocks). Buccal surface of 42 premolar teeth were flattened and etched then divided into 3 groups first group(P) received bonding agent then curing, second group (C) received bonding agent with no curing, third group(N)did not receive any bonding agent. Then each group is further subdivided into two subgroups according type of cement: light-cured luting cement total etch and a dual-cured self-adhesive resin cement.. All specimen underwent thermocycling aging and then shear bond strength test was carried out. A stereo microscope wasused to measure mode of failure of each specimen. Results: Regardless of type of cement co-curing application protocol had highest bond strength, followed by Noadhesive application protocol, while pre-curing application protocol had the lowest bond strength. Regardless of adhesive application protocol Self-etch dual-cured cement had a higher bond strength than the total-etch light-cured cement. While for mode of failure statistical analysis, there was no significant difference in adhesive application protocol and cement types. Conclusions: To Increase adhesive protocol the Co-curing is better than other methods. With regards toCement types, self-etch dual cure cement gave a more reliable bond than the total etch light cure cement