Purpose: To investigate the prosthetic parameters, clinical indices, crestal bone levels, and inflammatory biomarkers in peri-implant crevicular fluid (PICF) as influenced by two different implant restorative materials—metal-ceramic and monolithic zirconia—at baseline, 1 year, and 2 years. Materials and Methods: A total of 20 patients with bilateral implants placed in the same arch were selected. A monolithic zirconia (Mono-ZrO2; 4Y-PSZ) crown was placed on one side, and a metal-ceramic crown was placed on the contralateral side after randomization. Interproximal marginal bone level, clinical parameters, MMP-8 levels in PICF, and prosthetic characteristics (as determined by modified United States Public Health Service [USPHS] criteria) were evaluated at baseline and at 1-year and 2-year follow-ups. Data were descriptively examined. The results were evaluated using chi-square test, ANOVA, and Student t test. At P < .05, statistical significance was determined. Results: A total of 20 metal-ceramic crowns and 20 Mono-ZrO2 crowns were delivered. A 100% survival of the implants and prosthetic crowns was achieved across all patients, with no instances of failure noted throughout the 2-year follow-up period. The periodontal changes observed in the participants were analyzed and demonstrated statistically insignificant alterations. Prosthetic alterations were assessed according to USPHS criteria, revealing minor ceramic chippings and instances of screw loosening within the metal-ceramic group during both the 1- and 2-year follow-up periods. These incidents were collectively categorized as technical issues. Regarding anatomical form and color match to the surrounding dentition, Mono-ZrO2 crowns obtained much lower evaluations when compared to metalceramic crowns. However, when evaluating the loss of marginal bone and level of inflammatory markers, there were no discernible variations between the groups. Conclusions: The null hypothesis that there would be no similarity in the survival rates and interactions at the peri-implant interface between the two types of restorations was rejected. Mono-ZrO2 and metal-ceramic crowns demonstrated no statistical differences across all parameters examined in the present prospective investigation.
