Pink esthetic score outcomes around three implant-abutment configurations: 3-year results

PURPOSE: To evaluate the influence that three different implant-abutment interface designs had on peri-implant mucosal outcomes as assessed by the pink esthetic score (PES) 3 years after delayed implant placement and immediate provisionalization. MATERIALS AND METHODS: Adult subjects (n = 141) requiring replacement of a bounded single tooth in the anterior maxilla as well as first premolar sites were randomized to receive one of three unique implant-abutment interface designs (conical interface [CI]; flat-to-flat interface [FI]; or platform-switch interface [PS]). Treatment included immediate provisionalization with prefabricated titanium abutments, followed by custom computer-aided design/computer-aided manufacturing (CAD/CAM) zirconia abutments and cement-retained, all-ceramic crowns delivered after 12 weeks. Bilateral (anterior sites) or unilateral (premolar sites) digital clinical photographs were made at 1, 3, 6, 12, 24, and 36 months post-implant placement. Five calibrated faculty evaluators who previously scored the 1-year PES image dataset scored the 24- and 36-month photographs using a digital, cloud-based tablet interface. RESULTS: Six hundred ten clinical photographs were evaluated, resulting in a total of 3,050 sum PES values and 21,350 individual PES values. Faculty evaluator intrarater and interrater reliability were found to be "substantial," with intraclass correlation coefficient (ICC) values of 0.76 and 0.77, respectively. All three implant-abutment interface groups demonstrated acceptable esthetics at 3 years (mean sum PES = 10.1 ± 1.9, 4.0 to 13.2), with no single group demonstrating significantly greater mean sum PES values than another at the 3-year follow-up or at any recall interval in between. CONCLUSION: No significant differences were observed in mean sum PES scores for subjects randomized to one of three different implant-abutment interface geometries. Within the limitations of this study thus far, the first 6 months following definitive prosthesis delivery appear to still be the most significant with regard to improvement in PES outcomes for all three treatment groups.