One Piece CAD/CAM Abutment for Screw-Retained Single-Tooth Restorations: A 5-Year Prospective Cohort Study.

BACKGROUND:The use of ceramic-coated patient-specific CAD/CAM titanium abutments represents a therapeutic option for the rehabilitation of single tooth. The utilization of highly customized abutments enables the accurate three-dimensional positioning of the prosthetic emergence. This study evaluates the clinical performance of implant-prosthetic rehabilitations carried out using ceramic-coated CAD/CAM titanium abutments. MATERIALS AND METHODS:Thirty implants were placed in thirty patients and rehabilitated with thirty single crowns attached to CAD/CAM titanium abutments. A conventional procedure was applied, with implant placement after post-extraction socket healing and prosthetic restoration after implant healing. Implants of lengths ranging from 6-15 mm and widths of 3.6, 4.2, and 4.8 mm were used in this study. At the time of prosthesis delivery (T0), after two years (T1), and after five years (T2), plaque (PI) and bleeding (BoP) indices, probing depths (PPD), marginal bone levels (MBL), and PES/WES were evaluated for each implant. RESULTS:No patient dropped out of the study during the follow-up period. All thirty implants were clinically successful at five years post-prosthesis delivery (survival rate: 100%) and showed no signs of peri-implant infection. Peri-implant soft tissues were in good health (BoP at T2: 0% in 73% of patients; 25% in 13% of patients; 50% in 10% of patients; and 75% in 3% of patients). The mean PPD was 2.05±0.56 mm at T0, 1.992±0.6 mm at T1, and 1.867±0.439 mm at T2. The mean MBL at T0 was 0.413±0.440 mm, at T1 was 0.306±0.388 mm, and at T2 was 0.263±0.368 mm. The mean PES, WES, and PES/WES indices, 7.43±1.04, 7.57±0.82, and 15.00±1.17, respectively, indicate good integration of soft tissues, satisfactory aesthetics, and an overall positive outcome. CONCLUSIONS:The success rates, maintenance of marginal bone levels, and periodontal and aesthetic indices suggest the validity of implant-prosthetic rehabilitations with CAD/CAM abutments in cases of single crowns.