Color Stability and Surface Roughness of Micro‐Layered, Polished, and Glazed Zirconia Exposure to Cigarette Smoke, Tea, and Coffee

OBJECTIVE: This study evaluated the effects of micro-layering glaze, polishing, and conventional glaze on the color stability and surface roughness of zirconia after exposure to tea, coffee, and cigarette smoke. MATERIALS AND METHODS: Zirconia specimens (N = 180; 12 × 12 × 2 mm) were allocated into three surface-finishing groups: polishing, conventional glaze, and MiYO micro-layering glaze. Each group was subdivided into four staining subgroups (n = 15): distilled water, tea, coffee, and cigarette smoke. Specimens were exposed to protocols simulating 1 year of clinical use. Color change was assessed using the CIEDE2000 formula, surface roughness changes were recorded, and data were analyzed using the Kruskal-Wallis test with Conover post hoc comparisons. RESULTS: The surface-finishing protocol and staining agent significantly influenced color change and surface roughness. Cigarette smoke induced the greatest overall changes, with the highest values observed in the MiYO group. In contrast, after tea and coffee exposure, MiYO showed lower color change and surface roughness than polishing and conventional glaze. Polishing and conventional glaze yielded comparable outcomes across all staining conditions except cigarette smoke. CONCLUSIONS: Zirconia esthetic stability was influenced by surface finishing and staining agent. MiYO micro-layering was associated with lower color change and roughness after exposure to tea and coffee, but with greater susceptibility to cigarette smoke.