The effect of different parameters on the wear, surface properties, and shear bond strength of monolithic zirconia CAD/CAM restorative materials

To investigate the effects of preparation order and sandblasting procedures (different particle sizes and sandblasting times) on the wear, surface properties, and shear bond strength of zirconia material. A total of 130 test specimens were fabricated from Katana-Zirconia (n = 10). 70 test samples were sintered. Control, pre-sintered, and sintered groups were formed. The initial weights of the samples were measured. Sandblasting treatments were performed from a distance of 10-mm at 2-bar pressure for 10, 15, and 20-s with 29-µm and 50-µm Al2O3. The weight measurement was repeated. Subsequently, pre-sintered groups were sintered. Samples were scanned using a Nanovea-PS50. Ra, Rz, and Sa values ​​were recorded. Then, samples were embedded in acrylic. Composite bars were fabricated using a Teflon mold and bonded to the samples with G-CEM Link-Force. The shear bond strength test was performed. The data were analyzed using the Shapiro-Wilk test and two-way analysis ANOVA (p < 0.05). The highest Ra values were 1.198 ± 0.105 (Group-6) for PSZ and 0.267 ± 0.015 (Group-6) for SZ. Sa data demonstrated the highest values of 4.628 ± 1.541 (Group-6) for PSZ. The highest SBS values were 15.35 ± 2.75 (Group-4) for PSZ and 12.76 ± 2.39 (Group-1) for SZ. PSZ showed higher wear amount, Ra, Rz, Sa, and SBS in Groups 4 and 5 (p < 0.05). Pre-sintered and sintered zirconia showed different dependencies on sandblasting parameters regarding weight loss, Ra, Rz, Sa, and SBS. Sandblasting zirconia materials with 50-µm Al2O3 for 10 or 15-s before sintering may have beneficial effects on surface roughness and SBS.