Electronic assessment of peri-implant mucosal esthetics around three implant-abutment configurations: a randomized clinical trial

Objectives: To objectively assess the influence that three different implant–abutment interface designs had on peri-implant mucosal esthetics at 1 year post-implant placement via the pink esthetic score (PES). Additionally, to demonstrate the novel employment of a tablet-based digital imaging format to reliably assess and score clinical images as part of a multicenter clinical trial according to PES criteria. Materials and Methods: Adult subjects (n = 141) with healed tooth-bound edentulous sites in the anterior maxilla as well as first premolar region were randomized to receive one of three different implant–abutment interface designs (conical interface = CI; flat-to-flat interface = FI; or platform switch interface = PS). Immediate provisionalization was performed with prefabricated titanium abutments, with definitive custom CAD/CAM zirconia abutments and all-ceramic cement-based crowns being delivered 12-week post-implant placement. Bilateral (anterior sites) or unilateral (premolar sites) digital clinical photographs were made at 1, 3, 6, and 12 months post-implant placement. Five calibrated faculty evaluators of different clinical backgrounds scored images during a 4-week timeframe on a standardized, tablet-based, digital imaging format. Results: Six hundred and forty-nine clinical photographs were evaluated resulting in a total of 3245 sum PES values and 22,715 individual PES values. Faculty evaluator intra- and inter-rater reliability was found to be “strong” (ICC = 0.84) and “substantial” (ICC = 0.64), respectively, demonstrating repeatability of both the PES, evaluator calibration, and standardization of tabletbased scoring. All implant–abutment interface groups demonstrated significant improvements in mean sum PESs up to 1 year, with the largest improvement between restoration delivery and 6 months. No significant differences were found between groups in mean sum PESs both for individual study visits as well as for changes between study visits. Conclusions: No significant differences in mean sum PESs were found between subjects randomized to three different implant–abutment interfaces. However, significant differences were found as a function of time for all three groups, with the largest improvement in mean sum PESs occurring between definitive abutment and restoration delivery and 6 months. Use of electronic, tablet-based digital imaging scoring formats represents a novel and repeatable methodology for scoring PES images in large, multicenter clinical trials.