Abstract
Background: Zirconia ceramics are increasingly used for monolithic restorations due to theirfavorable mechanical and esthetic properties. However, their wear behavior against opposing enamel,particularly after different surface finishing procedures, remains a concern. Objective: This studyaimed to evaluate the influence of various polishing protocols on the wear of anatomic contour yttriastabilizedtetragonal zirconia polycrystal (Y-TZP) and an opposing enamel-mimicking material.Methods: Disk-shaped enamel-mimicking specimens (carbonate apatite, C/P=1, sintered at 800 °C)were fabricated. Y-TZP zirconia antagonists (Ø3mm, 6mm thick) were prepared and assigned tofour groups: (1) Polished with 4000-grit SiC paper (Struers)(ZP); (2) ZP + grinding with vitrifieddiamond (Shofu)(ZPG); (3) ZPG + polishing with Zircoshine (coarse, medium, fine; Shofu)(ZPGP);(4) ZPGP + polishing with Zircon-Brite (DVA)(ZPGPP). Two-body wear testing was performed (75N,10,000 cycles, 30° rotation, 37°C water). Zirconia wear was assessed by thickness decrease; enamelmimickingwear was measured as maximum surface depth (Rz, μm). Results: Significant differencesin wear were observed for the enamel-mimicking specimens. Wear (Rz) was greatest for ZPG (125.7μm), followed by ZPGP (13.8μm), ZPGPP (8.7μm), and ZP (1.8μm). No significant differences in wearwere detected among the zirconia specimens across the four finishing protocols. Conclusion: Withinthe limitations of this in vitro study, mirror-polished zirconia resulted in minimal wear of the opposingenamel-mimicking material.
