Fracture strength of anterior cantilever resin‐bonded fixed partial dentures fabricated from high translucency zirconia with different intaglio surface treatments

Purpose To compare the fracture resistance and failure modes of anterior cantilever resin‐bonded fixed partial dentures (RBFPDs) fabricated from high translucency zirconia with different intaglio surface treatments. Materials and methods Sound‐extracted canines (N = 50) were randomly divided into five groups (n = 10) to be restored with high translucency zirconia RBFBDs of different intaglio surface treatments. The RBFPD was designed using exocad software and fabricated using a CAM milling machine. The RBFPDs were treated differently: abrasion with 50 µm alumina particles (Group 1); abrasion with 30 µm silica‐coated alumina particles (Group 2); abrasion with silica‐coated alumina particles (30 µm) and silane application (Group 3); abrasion with silica‐coated alumina particles (30 µm) and 10‐methacryloyloxydecyl dihydrogen phosphate (10‐MDP) primer application (Group 4); abrasion with silica‐coated alumina particles (30 µm) and silane, and 10‐MDP primer application. All RBFPDs were cemented using dual‐cured resin cement. The RBFPDs underwent 6000 thermal cycles with distilled water at 5/55°C for 2 min per cycle and then mechanical cyclic loading with 1200,000 cycles of 50 N at a 1.7 Hz frequency at an angle of 135° to the abutment's long axis. Then, RBFPDs were loaded to fracture using a universal testing machine at 1 mm/min. Maximum fracture forces and failure modes were recorded. Fractured specimens and uncemented specimens were examined using a scanning electron microscope. Data was analyzed using ANOVA and Games–Howell post hoc tests at p