Effect of resin cement type and autoclaving on the retention of zirconia on Ti-base abutments.

Purpose: The cement interface is particularly important for successful zirconia-titanium base (Ti-base) restorations, as retention relies primarily on adhesive bonding. The aim of this in vitro study was to assess and compare the influence of a universal resin cement used with either a self-adhesive or adhesive bonding protocol versus adhesive resin cements on the retention of zirconia to Ti-base abutments, with and without autoclaving.

Materials and methods: Zirconia buildups were cemented to titanium-base abutments using RelyX Universal (RXU) as a self-adhesive resin cement, RXU with a primer (RXU/SUP), Panavia V5 (PV5) with primer, or multilink hybrid abutment (MHA) with primer. Half of the specimens were autoclaved. Push-out testing was performed, and data were statistically evaluated using the analysis of variance (ANOVA), Tukey honest significant difference test, and family-wise error rate method.

Results: Of the nonautoclaved groups, RXU/SUP showed the highest initial mean push-out load (1576.45 ± 195.86 N), followed by MHA (1268.10 ± 160.67 N), RXU (959.66 ± 139.24 N), and PV5 (905.84 ± 298.38 N). Autoclaving did not have a significant influence on cement push-out load when compared directly within cement pairs. The push-out load of RXU used as self-adhesive cement was similar to PV5 with primer. Retention of RXU/SUP and MHA groups was significantly higher than that of RXU or PV5.

Conclusion: In this in vitro study, RXU performed as well as PV5 groups and required the fewest preparation steps, suggesting it may be a good option for improving workflow efficiency. Results indicated a marginally positive effect of autoclaving between pairs, however, it was not significant.