Objective: To determine the shear bond strength (SBS) of 4 resin cement systems to zirconia using a zirconia primer.
Methods: 10mm x 4 mm Zirconia disks were prepared and sintered .The surface of the disks were treated by air abrading with 50 µ alumina. Cylinders of resin cement (ResiCem (RC), MaxCem Elite (M) SmartCem 2 (SC) and Rely-X ARC (R) were bonded using an Ultradent bonding apparatus. 4 groups for each cement were prepared: light curing the cement (VLC), auto-curing the cement (AC), and VLC and AC after applying AZ bonding primer to the zirconia surface. 12 specimens for each system were stored for 24 hours prior to deboning. The specimens were loaded to failure at a speed of 1 mm/min. Statistical analysis included 3-way ANOVA (factors: cement, curing mode and primer) and LSD post hoc test.
Results: (in Megapascals MPa):
| VLC | AC | VLC/ AZ primer | AC/ AZ Primer |
RC | 6.0 +/- 2.2 | 5.1 +/- 5.1 | 7.6 +/- 3.4 | 11.7 +/- 4.2 |
M | 5.5 +/- 5.1 | 3.7 +/- 4.2 | 2.3 +/- 1.9 | 3.7+/- 3.4 |
SC | 2.2 +/- 0.76 | 2.2 +/- 2.2 | 4.4 +/- 2.6 | 3.1+/- 2.2 |
R | 0.75 +/- 0.9 | 1.3 +/- 0.9 | 2.5 +/- 1.3 | 3.7 +/- 2.7 |
Significant differences were observed among the cements and experimental conditions and all three factors, cement, curing mode and use of the primer were significant (p<0.05). AZ primer significantly improved SBS of RC to zirconia in the autocured specimens (p<0.05).With the primer, RC also generated the highest SBS for both curing conditions compared to the other cements tested.
Conclusion: Significant differences were observed in the SBS of resin cements to zirconia. Resicem using the AZ primer generated the highest SBS for both VLC and AC curing conditions. Supported by Shofu Dental.