The Effect of Resin Cement Type and Thermomechanical Aging on the Retentive Strength of Custom Zirconia Abutments Bonded to Titanium Inserts.

PURPOSE

The purpose of this study was to investigate the effect of resin cement type on the retentive strength of custom zirconia abutments bonded to titanium inserts.

MATERIALS AND METHODS

Sixty implant (4.3 mm diameter and 11.5 mm length) and custom zirconia abutment (15 mm height and 2 mm wall thickness) pairs were used to form six groups (n = 10 each). Three different resin cements were used to bond the zirconia abutments and titanium inserts: Panavia F 2.0, Zirconite, and Multilink Hybrid Abutment. Control groups and thermomechanically aged groups were formed. Specimens were subjected to tensile test to failure, and the retention values were analyzed by two-way analysis of variance (ANOVA).

RESULTS

Two-way ANOVA showed a significant effect of the cement type and thermomechanical aging (P < .05). Regardless of the cement, control groups showed significantly (P < .05) higher retentive strength than the thermomechanically aged groups. Comparing the resin cements, the retentive strength of Zirconite, aged or not, was higher than that of Panavia F 2.0 and Multilink Hybrid Abutment; no significant differences between the latter two cements were found. In the Zirconite group, adhesive failure occurred mostly between the titanium and the resin cement. In the Panavia F 2.0 and Multilink Hybrid Abutment groups, adhesive failure between the zirconia and the resin cement was observed.

CONCLUSION

Resin cement type had an effect on the retentive strength of custom zirconia abutments bonded to titanium inserts. Thermomechanical aging had a negative effect on the retentive strength. Zirconite adhesively bonded to the zirconia surface of the custom abutment. Differences were noted in adhesive failure types among the cements.