Push-out bond strength of ceramic inlays cemented with contemporary resin cements

Objective: To compare the push-out bond strength of ceramic inlay materials bonded to dentin using two different types of contemporary luting cements. Methods: Standardised occlusal cavities (5 mm in occlusal diameter, 3.5 mm in cervical diameter and 3.5 mm deep) were prepared using a truncated cone-shaped diamond rotary cutting instrument. The prepared cavities were restored in 2 groups with IPS e.max CAD (IPS) (G.1) and zirconia-based (Zr) (G.2) ceramic inlays (n=20 each). Inlays of each group were cemented in 2 subgroups (n=10) using either self-adhesive (SG:A) or conventional etch-and-bond (SG:B) resin cement. Half the specimens in each subgroup (n=5) were subjected to thermocycling, and the crowns of all teeth were then trimmed to a standardised thickness nearly of 3.5mm. The push-out bond strength was tested on a universal testing machine. Assessing the bond failure was also considered. Results: The 1-way ANOVA showed insignificant differences between the push-out bond strength values of all tested subgroups (p= 0.7161). The statistical analysis of the recorded frequencies of different modes of bond failure showed no differences between the tested subgroups (chiᴧ2, p = 8.4283). Conclusion: Neither the type of ceramic nor resin cement has an effect on the bonding values to dentin. Thermocycling of bonded inlays has no adverse effect on their bonding values, although the mode of failure could be affected. Keywords: ceramic, inlays, push-out, bond strength, adhesive resin cement