Randomized Controlled Clinical Trial Comparing Screw-Retained Monolithic Zirconia Implant Crowns on Standardized Titanium Base Versus Customized Titanium Abutments- 3-Years Data.

OBJECTIVES: To assess 3-year interim results of implant-supported monolithic zirconia single crowns on standardized titanium base vs. customized titanium abutments. MATERIAL AND METHODS: Patients in need of posterior implant were recruited. After implant healing time, patients were randomly allocated to: Ti-Base (n = 30) with a monolithic zirconia crown on a standardized Ti-Base abutment or Custom (n = 30) with a monolithic zirconia crown on a customized titanium abutment. Implant crowns were evaluated at Baseline (BL), 1-year (1Y-FU), and 3 years (3Y-FU) follow-ups for marginal bone level changes (MBL), survival, biological and technical outcomes, and PROMs. Chi-squared and Fisher's exact test were used to assess association between categorical variables, Mann-Whitney's test to compare the distribution of parameters between groups, with a significance level of 5% (α = 0.05). RESULTS: Fifty-one patients (23 Custom, 28 Ti-Base) attended 3Y-FU visit. No implant crowns were lost. Similar median MBL changes from BL to 3Y-FU and comparable biological outcomes were observed in both groups (p > 0.05). No major technical complications were observed, but one minor chipping of Ti-Base zirconia crown was recorded at 3Y-FU, resulting in a technical complication rate of 3.6% for this group. At the 3Y-FU, all patients in the Custom group and 26 patients (92.9%) in the Ti-Base group were very satisfied with the treatment (p > 0.05). CONCLUSIONS: Within the limitations of this interim analysis, monolithic zirconia single crowns on either standardized titanium base or customized titanium abutments demonstrated stable marginal bone levels, high survival rates, high patient satisfaction, and no major technical complications during the 3Y follow-up period. TRIAL REGISTRATION: https://drks.de/search/en/trial/DRKS00012733.