Statement of Problem: Do the different zirconia generations respond similarly to the same bonding protocol of self-adhesive resin containing MDP.
Materials and Methods: Four groups of zirconia specimens were used (n=10 each): according to the generation of zirconia used: group Hi Translucent is generation 1, group Super Translucent is generation 2, group Top Translucent is generation 3, and group Esthetic Explore is generation 5. Ten zirconia cuboids were dry-milled of each of the 4-zirconia blocks using a CAD CAM milling machine then sintered in a ceramic oven. Forty composite cuboids 4X4 were fabricated and cemented using self-adhesive resin cement containing MDP to each zirconia cuboid using custom constructed Plexi-Frames. All specimens were thermally cycled and subjected to shear bond strength in the universal testing machine.
Results: The mean SBS was higher in EX group (30.58+ 11.9) followed by HT group (23.16+ 3.6), then TT group (21.59+ 6.6), and finally ST group (21.47+ 6.1). One-Way ANOVA revealed a significant difference in SBS between tested groups.
Conclusions: The 5th generation of zirconia scored the highest mean SBS values. More surface treatment protocols should be suggested for each zirconia generation.