Clinical performance of ultratranslucent monolithic zirconia posterior crowns compared with lithium disilicate crowns: A pilot, randomized, double-blind, controlled clinical trial

Purpose: To evaluate, through a pilot, randomized, double-blind, controlled clinical trial, the clinical performance of ultratranslucent monolithic zirconia (UTZr) compared to lithium disilicate (LD) posterior crowns after 24 months of follow-up. Materials and Methods: Twenty-four crowns were fabricated and placed in 18 patients, assigned to 2 groups: Control (LD—IPS e.max CAD/Ivoclar) and Experimental (UTZr—Zircon FitPlus/Talmax). Longevity was assessed using the modified United States Public Health Service (USPHS) Ryge criteria, visual analog scales (VAS) for patients’ self-perceived esthetics, and the Oral Impacts on Daily Performances (OIDP) index for quality-of-life evaluation. Evaluations were conducted at baseline (T0) and 1 (T1), 6 (T2), 12 (T3), and 24 (T4) months after cementation. Survival analysis was performed using the Kaplan-Meier method with log-rank test (α =.05). OIDP and USPHS data were analyzed descriptively, while VAS esthetic satisfaction was analyzed using Mann-Whitney, Friedman, and Wilcoxon post-hoc tests. Results: The mean age of participants was 38.5 years. Eleven crowns were fabricated with LD and 13 with UTZr. After 24 months, the cumulative survival rate was 100% for both groups. Both groups showed a significant improvement in esthetic satisfaction over time (P<.05). No ceramic fractures, occlusal changes, marginal integrity alterations, or secondary caries were observed; however, one UTZr crown presented minor marginal discoloration. Conclusions: Both materials, ultratranslucent monolithic zirconia and lithium disilicate, demonstrated high survival rates and satisfactory clinical performance after 24 months.