Clinical performance of implant crowns with customized zirconia abutments. A prospective cohort study with a 4.5- to 8.8-year follow-up.

Objective To assess the clinical and esthetic outcomes and patient satisfaction of screw-retained one-piece implant crowns fabricated with zirconia abutments after a 4.5- to 8.8-years follow-up. Materials and methods Thirty-two patients (12 women, 20 men), who received 40 implant single crowns in anterior and premolar sites were included in this prospective study. All restorations were based on ceramic hand-veneered customized CAD/CAM zirconia abutments. The follow-up consisted of clinical and radiological examinations. The Pink Esthetic Score-White Esthetic Score (PES-WES) was used to evaluate the esthetic outcome. Patients' satisfaction was assessed via visual analog scale (VAS). Results Implant and prosthetic survival rates were 100% and 97.5%, respectively. Mean marginal bone loss was -0.17 mm (SD 1.16 mm). Probing depth was ≤ 4 mm in 98.7% and 5 mm in 1.3% of the sites; 8.3% of them were bleeding-on-probing positive. No technical or biological complications were observed except for one abutment fracture. The mean PES-WES scores were 7.0 and 7.1, respectively. VAS scores (10-point) of 9.41 for function and 9.26 for esthetics showed high patient satisfaction. Conclusion After a mean observation period of 6 years and 7 months, screw-retained implant crowns based on veneered customized CAD/CAM zirconia abutments with conical connection showed very good clinical performance and may be recommended for the replacement of missing anterior and premolar teeth.