Crestal Soft Tissue Thickness before Implant Placement and Its Relationship with Crestal Cortical Bone Thickness: A CBCT Based Retrospective Study

Abstract Background: Adequate peri‑implant mucosal thickness has been associated with improved marginal bone stability. This study quantified crestal soft tissue thickness at edentulous implant sites using CBCT and examined its relationship with crestal cortical bone and buccal/lingual cortical plates 5 mm apical to the crest. Methods: Retrospective analysis of CBCT scans from 10 adults (21 edentulous sites). Measurements (mm): (1) crestal soft tissue at the alveolar crest; (2) crestal cortical bone at the crest; (3) buccal and lingual cortical plates 5 mm apical. Descriptive statistics and Pearson correlation (α = 0.05) were used. Results: Mean crestal soft tissue thickness was 2.41 mm (median 2.2; range 1.41–4.87). Anterior sites were thicker than posterior (2.74 ± 0.28 vs 2.08 ± 0.19 mm). Mean crestal cortical bone was 1.42 mm (median 1.40). Buccal and lingual cortical plate means at 5 mm apical were 1.29 mm and 1.69 mm, respectively. Crestal soft tissue thickness positively correlated with crestal cortical bone (p < 0.001). Conclusions: More than half of implant sites exhibited thick crestal soft tissue (> 2 mm). Crestal soft tissue thickness was significantly associated with crestal cortical bone thickness but not with buccal/lingual plates 5 mm apical. Pre‑surgical CBCT assessment provides actionable, non‑invasive information for implant planning.