Aim: To evaluate effect of ceramic veneer type and thickness on light attenuation and microhardness of light-polymerized resin cements.
Methodology: Three types of ceramic blocks were used (IPS E.max-CAD, Celtra-Duo and VITABLOCS Esthetic-Line). Specimens measuring .5, 1 and 1.5 mm were cut. Deep-cure and Blue-phase light-polymerizations units were used. Light irradiance through specimens was measured with MARC-Patient Simulator. Rely-X Veneer and Variolink-Esthetic resin cements were polymerized through ceramic specimens for 10 and 20 seconds. Microhardness of cement specimens was measured using tester with Knoop indenter.
Result: Ceramic type and thickness had statistically-significant effects on light attenuation. Mean microhardness of Rely-X Veneer cement was significantly higher than that of Variolink Esthetic. Moreover, direct correlation was found between polymerization time and mean microhardness for both cements.
Conclusions: Increased veneer thickness negatively affected light irradiance in a significant manner. Light attenuation resulted in significant decrease in mean surface microhardness for both cements.M.Sc
