Implant‐supported single all‐ceramic crowns made from prefabricated (stock) or individualized CAD/CAM zirconia abutments: A 5 year randomized clinical trial

Abstract Aim The aim of this randomized, prospective, and clinical multicenter study was to compare the overall clinical performance of two restorative options over a 5‐year period: individualized CAD/CAM abutments veneered with a hand‐layered ceramic, and prefabricated zirconium dioxide abutments veneered with press ceramic and inserted into a single edentulous gap in the anterior maxilla. Materials and Methods Forty subjects were recruited from two universities: 20 from the University of XX and 20 from the University of XY. Each subject received an implant to restore a single edentulous gap in the maxillary anterior region (14–24 FDI). 20 patients were randomized into each Group. Group A received a one‐piece single crown produced from a prefabricated zirconia abutment with pressed ceramic and Group B received an individualized CAD/CAM zirconia abutment with a hand‐layered technique. After 5 years, the aesthetic and radiographic parameters were assessed. Results Group A had four dropouts and one failure, resulting in a 95% survival rate and 95% success rate. Group B had two dropouts and two failures which resulted in a 90% survival rate and 90% success rate. No crestal bone level changes were observed, with a mean DIB of 0.06 mm in Group A and 0.09 mm in Group B. No statistically significant differences were present at baseline, 6 months, 1 year, 3 years, or 5 years for DIB values between time points and groups. Pink aesthetic score/white aesthetic score, Peri‐Implant and Crown Index, and Implant Crown Aesthetic Index values were stable over time at all five points for both groups. Conclusion Both implant‐supported restorative options represent a valuable treatment option for the restoration of implant crowns in the anterior maxilla. Clinical Significance In general, the use of ceramic abutments in the anterior zone represents a valuable treatment procedure with both standardized and CAD/CAM individualized abutments and following the recommendations from the respective manufacturer(s).