Bond strength of zirconia ceramics applied with a ph-cycling model and different repair methods

Abstract

Purpose: To evaluate the shear bond strength of yttria-stabilized zirconia (YSZ) ceramics based on the type of surface treatment, repair kit, and aging method used. Methods: YSZ ceramic blocks (N = 120) measuring 6 mm x 8 mm x 8 mm were randomly and equally divided into three groups for different surface treatments: (a) surface treatments recommended by the manufacturer (control), (b) air abrasion, and (c) Er:YAG laser. After surface treatment, either the Cimara intraoral ceramic repair kit or the Bisco intraoral repair kit were used on the samples. A resin composite was incrementally applied to the treated surfaces and light cured. Repaired samples were aged using either thermocycling or pH cycling. A shear bond strength test was conducted on all samples, and failure patterns were examined under a stereomicroscope. Data were analyzed using three-way ANOVA, Kruskal-Wallis, Mann -Whitney U, and Bonferroni corrected paired comparison tests. Results: Interactions were found between aging methods, surface treatments, and repair kits, as well as between repair kits and surface treatments (P< 0.05). Although there was no statistically significant difference in bond strength values between the air abrasion and control groups in the thermal cycle (P= 0.053) and pH cycle (P= 0.104) for the Cimara repair kit, the bond strength values of the Er:YAG laser groups were statistically significant (P< 0.001). For the Bisco intraoral repair kit, there was a statistically significant difference in bond strength values between surface treatments in both aging methods (P< 0.001). All groups showed 100% adhesive failure.