A Comparatere study of the effect of 3 Resin luteng Cements on shear bond strength of Porcelain to dentin

i ncreasing esthetic demands in patients have led to increasing use of ceramic as a restoration. Meanwhile the bond strength of ceramic to dention is a challenging factor. This study aimed to compare the effect of 3 different resin cements on shear bond strength of porcelin to dentin. Thirty freshly extracted bovine incisors were used for this investigation. Following extraction and cleaning, teeth were stored in a 0. 2% Thymol solution for 48 hours and then randomly divided in to 3 groups of 10 each. Teeth underwent a 2mm preparation on the buccal surface in order to expose fresh dentin. Porcelain tubes, 3mms in diameter and 3 milimeters in height, were then bonded to the dentin using RelyXARC, Nexus, and Punavia F2 samples were then light – cured for a total time of 120 seconds (40 seconds for each directions) using Coltolux 2/5 USA light-curing unit with an intensity of 400 mw/cm. Two Samples were then stored a temperature of 37ْC for 24 hours and finally thermocycled (500 times +5__+55). Then, They were for shear bond strength with Zwick with a chisel – like shearing device till fracture occurred at 0. 5 mm/min cross head speed. Shear bond strengths in Mpa was as follows’: Mean Standard deviationRelyX ARC 3. 56 ± 0. 82Panavia F2 6. 09 ± 0. 54Nexus 4. 46 ± 0. 59 Panavia F2 revealed a significantly higher shear bond strength compared to the other groups. Nexus demonstrated a higher shear bond strength compared to RelyX ARC but this difference was not statistically significant.