Bonded and Self-Adhesive Cements' Bond Strengths between Zirconia-Crowns and Dentin

Objective: To examine the retention strengths of two different cement types—Bonded Resin Cements and Self-Adhesive Resin Cements— between zirconia crowns and dentin in vitro. The following groups were tested:

Group 1: Self-Etch/Self-Adhesive Resin-Cement: Set (SDI)

Group 2: Self-Etch/Self-Adhesive-Resin-Cement: Maxcem (Kerr)

Group 3: Self-Adhesive-Resin-Cement: Rely-X Unicem Clicker (3M ESPE)

Methods: Fifty-one extracted human molars were prepped for all-ceramic crowns. The crowns were cemented according to manufacturers' directions for each of the three cement groups (N=17). Cemented teeth were stored in distilled water for 3 days at 37°C and then thermocycled for 300 cycles between 5°C and 55°C with a dwell of 30 seconds. Instron machine with crosshead speed of 5mm/min was used to pull the crowns until failure.

Results: The strength data was compared using one-way analysis of variance (ANOVA). The p-value of 0.086 suggests that there is no statistically significant difference among the 3 groups. The average bond strengths were Group 3=316.8N, Group 1=284.4N, and Group 2 =208.7N.

Conclusion: There was no statistically significant difference between the bond strengths in each group.

Research sponsored in part by SDI.