Dynamic monitoring and esthetic evaluation of dimensional changes in the peri-implant soft tissue contour after the immediate implant placement and provisionalization with the modified socket-shield technique in the esthetic zone

Abstract

Objective: To accurately measure the dynamic changes of peri-implant soft tissue within one year after the immediate implant placement and provisionalization with the modified socket-shield technique (MSST) in the esthetic zone, and to provide a basis for evaluating the effect of the modified socket-shield technique on the maintenance of peri-implant soft tissue. Methods: A total of 22 patients (22 implants) were prospectively included 1 year after completion of immediate implant placement and provisionalization (IIPP) within MSST in the esthetic zone from January 2022 to January 2024 at the Department of Oral Implantology in the Stomatological Hospital of Chongqing Medical University. The intraoral optical models of patients were obtained by an intraoral scanner system preoperatively and at 3, 6, and 12 months postoperatively, respectively. The standard tessellation language files of intraoral optical models at multiple time points were imported to Geomagic Studio 2013 to be superimposed and aligned for analyzing the peri-implant soft tissue contour on the labial side of the implant site at multiple levels. The amount of gingival margin recession, gingival papilla change, and thickness change of the labial side of the soft tissues at each postoperative point in time were measured at each postoperative time point, as well as evaluating the esthetic effect by the pink esthetic score (PES). Results: The patients were (40±13) years old (21-75 years), including 9 males and 13 females. No adverse events occurred in all the implants during the 12-month follow-up period. The recession level of the gingival margin of the implant site (GL) was 0.08 (0.07) mm, the recession level of the mesial papilla (ML) was 0.19 (0.25) mm, and the recession level of the distal papilla (DL) was 0.19 (0.10) mm. The average collapse thickness of the soft tissue contour on the labial side of the implant (ΔD) was (0.39±0.09) mm, mainly occurring within 2 mm of the root of the gingival margin. The height of the alveolar bone was reduced by (0.17±0.08) mm. The thickness of the labial alveolar bone at 1, 3, and 5 mm root side of the implant shoulder was reduced by (0.13±0.08), (0.12±0.10) and 0.04 (0.17) mm, respectively. The postoperative pink esthetic score was 13.00 (2.25) points at 12 months, which suggested that all implant sites achieved ideal esthetic results. Conclusions: The labial soft tissue contour at implant sites shows minimal change following immediate implant placement and provisionalization using the modified socket-shield technique for 1 year in the esthetic zone.