Three-Dimensional Digital Quantification of Peri-Implant Mucosal Volume Using Intraoral Scanning

Abstract

Background:
Peri-implant soft-tissue dimensions play an important role in maintaining peri-implant health and achieving stable esthetic outcomes. Three-dimensional (3D) volumetric assessment may provide additional quantitative information on peri-implant soft-tissue changes beyond conventional linear clinical measurements.
Aim:
To evaluate changes in peri-implant mucosal volume and thickness and to determine their associations with selected clinical and soft-tissue parameters over a 6-month follow-up period.
Materials and Methods:
This prospective comparative clinical study included 40 participants who were evaluated at baseline, 3 months, and 6 months. Peri-implant soft-tissue characteristics were assessed using 3D digital volumetric measurements and conventional clinical parameters. Peri-implant mucosal thickness, keratinized mucosa width, probing depth, plaque index, and bleeding on probing were recorded at the specified examination points. Changes in peri-implant mucosal volume were assessed over time and between groups, and correlation analysis was performed to determine associations between percentage mucosal volume gain and selected clinical parameters. Measurement reproducibility was evaluated using intra- and inter-examiner intraclass correlation coefficients (ICCs).
Results:
Peri-implant mucosal volume demonstrated progressive changes over the 6-month follow-up period. At 6 months, percentage mucosal volume gain showed a strong positive correlation with mucosal thickness in Group A (r=0.68, p<0.001) and a moderate positive correlation in Group B (r=0.55, p=0.012). Keratinized mucosa width was positively correlated with volumetric gain in both groups, with a statistically significant association observed in Group A (r=0.46, p=0.041). Probing depth showed a significant inverse correlation with percentage volume gain in Group A (r=-0.51, p=0.021). Bleeding on probing demonstrated a borderline inverse association with volume gain in Group A (r=-0.44, p=0.050). At 6 months, the mean plaque index was 0.38 ± 0.21 in Group A and 0.59 ± 0.27 in Group B, with a statistically significant intergroup difference (p=0.011). The reproducibility of 3D volumetric measurements was excellent, with intra-examiner and inter-examiner ICCs of 0.96 and 0.93, respectively.
Conclusion:
3D volumetric analysis demonstrated excellent measurement reproducibility and provided quantitative assessment of peri-implant mucosal changes over 6 months. Percentage mucosal volume gain was associated with mucosal thickness, keratinized mucosa width, and selected clinical peri-implant parameters. Lower plaque accumulation was also observed in Group A at 6 months. 3D volumetric assessment may serve as a useful adjunct to conventional clinical evaluation of peri-implant soft-tissue stability.