Objective: This study was conducted to evaluate the effect of self-etch adhesives on bond strength of self adhesive resin cements. Methods: Five cements were selected: SmartCem2 (SC), Unicem Clicker (UC), Maxcem (MC), G-Cem (GC) and i-Cem (IC). Six adhesives were used: Xeno IV (Xeno), Adper Scotch Bond SE (ASBS), Adper Easy Bond (AEB), OptiBond All-In-One (OAIO), G-Bond (GB) and i-Bond (IB). Extracted human molars were wet ground to expose flat surfaces using 320 and 600 grit abrasive paper. Adhesives were applied and light-cured per manufacturers' instructions. Cement was loaded to plastic straw, placed onto tooth surface and allowed self-cure. Specimens were stored in 37°C water for 24-hr. Shear bond strength (SBS) was obtained with Instron 4400 at crosshead speed of 1 mm/min. The data was analyzed with ANOVA (n=6, a=0.05, Tukey HSD test). Results: Mean values for SBS (MPa) with standard deviations are listed below:
| Adhesives | SC-Xeno | UC-ASBS | UC-AEB | MC-OAIO | GC-GB | IC-IB |
Dentin | None | 3.8(0.5)A | 3.4(1.8)A | 3.4(1.8)A | 2.8(0.5) A | 3.2(1.3) A | 2.2(0.7) A |
Yes | 17.4(2.8)A | 13.3(1.4)B | 17.0(1.4)AB | 17.5(3.5) A | 7.2(1.2)C | 8.2(3.0) C | |
Enamel | None | 5.6(1.3)A | 5.3(1.2)A | 5.3(1.2)A | 4.3(1.3) A | 6.3(0.9) A | 5.4(1.7) A |
Yes | 14.9(2.8)A | 14.9(1.5)A | 9.2(2.3)B | 12.7(2.0) AB | 12.7(3.5) AB | 9.8(3.4) B |
*Within the same row, groups connected by the same letter are not significantly different.
Conclusion: All tested self-etch adhesives significantly enhanced bond strength of the respective self adhesive cements in self-cure mode. On dentin, SmartCem2/Xeno IV, Unicem/Adper Easy Bond and Maxcem/OptiBond All-In-One exhibited significantly higher bond strength than G-Cem/G-Bond and i-Cem/i-Bond. On enamel, SmartCem2/Xeno IV and Unicem/Adper Scotch Bond SE displayed significantly higher bond strength than Unicem/Adper Easy Bond and i-Cem/i-Bond.