Abstract
OBJECTIVES: This prospective cohort study aimed to evaluate the clinical and radiographic outcomes of one-piece zirconia implants and compare them to those of titanium implants over a period of up to 108 months (85.3 ± 31.6 months). METHODS: A total of 33 implants (22 zirconia/Ziterion Zit-Z® and 11 titanium/Ziterion Zit-T®) were placed in 32 patients (15 male, 17 female), all of whom required neither bone nor soft tissue augmentation. These implant systems are no longer commercially available. Radiographic bone levels, clinical peri-implant parameters, and implant survival were recorded for up to 108 months. RESULTS: Implant fractures were not observed. In the titanium group, two implant failures (18.2%) were reported, while eight zirconia implants (36.4%) failed. Kaplan-Meier analysis showed survival rates of 80.8 and 62.2% for titanium and zirconia implants, respectively, for up to 108 months. The bleeding on probing values gradually increased over time in both groups. A statistically significant decrease in the plaque index was observed for zirconia implants at 36 and 108 months (p < 0.001). Additionally, both groups showed a statistically significant reduction in marginal bone resorption within the first year after implant placement (p < 0.05). However, no significant difference between the two groups was observed over time (p > 0.05). CONCLUSIONS: Immediately temporized one-piece zirconia implants showed lower survival rates than those of titanium implants, highlighting the need for further validation in larger trials. CLINICAL RELEVANCE: Immediate temporization of non-commercial zirconia implants is not recommended due to their compromised survival rates.