The Effect of Different Surface Treatments on the Color and Translucency of Zirconia: An In Vitro Study

Background/Objectives: To compare the effects of different surface treatments on the color and translucency of three types of zirconia ceramics. Methods: Ninety CAD/CAM-milled zirconia disks (10 mm diameter, 1 mm thickness) were fabricated from Cercon HT (3-YTZP), IPS e.max ZirCAD MT (4-YTZP), and Cercon XT (5-YTZP). Baseline CIE Lab* coordinates were measured using a digital spectrophotometer. The disks underwent one of three surface treatments: 50 µm alumina air-particle abrasion (AAA), Zircos-E etching (ZE), or 100 µm glass bead air-particle abrasion (GBA). Post-treatment CIE Lab* measurements were obtained, and color change (ΔE00, CIEDE2000) and translucency change (ΔTP00) were calculated. Results: Regarding color change (ΔE00), 50 µm AAA produced the greatest change, followed by ZE, while GBA caused the smallest change. Surface treatment and its interaction with material type were found to exert a significant effect, whereas material type alone was not significant. Cercon XT showed the highest numerical ΔE00 value among the materials, although the difference was not statistically significant. All ΔE00 values were below the clinical acceptability threshold (<1.8). No significant effects of surface treatment, material type, or their interaction were observed for translucency change (ΔTP00) after surface treatment. Baseline translucency values (TP00) differed significantly, with Cercon XT being the most translucent, followed by ZirCAD MT and Cercon HT, but these differences did not result in significant ΔTP00 changes post treatment. Conclusions: Surface treatments and their interaction with material type significantly affected zirconia color change, with 50 µm alumina air-particle abrasion producing the most pronounced effect. Material type alone did not significantly influence ΔE00, though Cercon XT showed the highest numerical value. Translucency change (ΔTP00) after treatment was unaffected by surface treatment or material–treatment interaction.