RESUMO
Introduction: The aim of this study was to compare the shear bond strengths of zirconia to dentin using two resin-based luting cements and a resin-modified glass-ionomer cement (RMGIC). Materials and Methods: Thirty six zirconia blocks of 2 mm × 3 mm × 5 mm were milled and luted to the exposed dentin surfaces and grouped into three according to the cement used for luting: Group I - luted with Panavia F2.0, Group II - luted with RelyX U200, and Group III - luted with FujiCEM. After thermocycling, specimens were subjected to shear bond testing in an Universal Testing Machine (UTM). Data analysis using Kruskal-Wallis ANOVA and post hoc Mann-Whitney U-test with P < 0.05 was done. Results: Mean bond strengths were of the order Panavia F2.0 (5.99 MPa)>RelyX U200 (4.79MPa)>FujiCEM (1.59 MPa). Maximum failures were at the zirconia-cement interface and were adhesive in nature. Conclusions: It can be concluded with the study that there is a better bonding of zirconia to dentin with resin-based luting cements than a RMGIC. The single-step resin-luting cement RelyX U200 produced comparable bond strength to that of a multistep Panavia F2.0.