The Effect of ZrO₂ Slurry on Zirconia Surface Roughness, Crystal Phases, and Shear Bond Strength With Resin Cement

This study aimed to examine the effect of applying zirconia slurry on the surface roughness of zirconia and its resulting crystal phases, and shear bond strength with resin cement.

Two hundred and ten zirconia discs, prepared through the slip-casting and milling methods, 18 mm in diameter and 2.5 mm in thickness, were categorized into five groups according to surface treatment: no surface treatment (C and CM), 50 μm alumina air-abrasion (SB), and zirconia slurry sprayed with concentrations of 15% w/w and 30% w/w (ZS15 and ZS30). After surface treatment, all specimens underwent examination for surface roughness reported as arithmetical mean height (Sa) and maximum height (Sz), x-ray diffraction analysis for monoclinic phase detection, and were bonded with resin cement to perform shear bond strength (SBS) testing. Data were analyzed using one-way ANOVA and Tukey's HSD at the significant level of 0.05 (α = 0.05).

Sa and Sz values exhibited no statistically significant differences among all groups (p > 0.05). Crystal phases of all groups presented peaks of monoclinic and tetragonal phases. SBS values of all groups also demonstrated no statistically significant differences (p > 0.05).

The zirconia slurry might not significantly affect the surface roughness, crystal phases, and SBS of slip-casting zirconia.