Purpose: To report on the follow-up of two earlier published RCTs on the performance of screw-retained monolithic zirconia restorations on Ti-base abutments based on intraoral optical scanning or conventional impressions.
Materials and Methods: A total of 54 patients receiving 89 restorations (44 single crowns [SC]), 21 splinted crowns [2-FDP], and 24 three-unit fixed partial dentures (3-FDP)] were included in the 1- to 3-year follow-up period. The restoration survival and technical complications were documented.
Results: A total of 50 patients with 84 restorations completed the 3-year follow-up. One 3-FDP from the IOS group was lost. This resulted in survival rates of 97.9% for the test and 100% for the control restorations and an overall survival rate of screw-retained monolithic zirconia restorations on implants of 98.8% after 3 years. There was no statistically significant survival difference between the test and control groups (P = .362). When evaluated separately, a 100% survival rate for SCs and 97.7% rate for 2-FDPs was reported. One decementation and three occurrences of screw loosening occurred over the 1- to 3-year follow-up. The multiple-implant restorations showed higher (23.3%) complication rates at the restoration level than the SCs (4.9%) after 3 years of function (P = .026).
Conclusion: Screw-retained monolithic zirconia restorations on Ti-base abutments show promising survival rates after 3 years of function. Restorative complications of screw-retained monolithic zirconia restorations on Ti-base abutments are more likely to happen in the first year of function and are more common in multiple-implant restorations than solitary crowns. The impression (IOS or conventional) does not seem to influence these results.
