Stability of soft tissue augmentation at implant site using volume-stable collagen matrix: 2-year retrospective study.

Abstract

Objective: To evaluate the long-term dimensional stability of dental ridges two years after soft tissue augmentation using a porcine-derived volume-stable collagen matrix (VCMX) at healing abutment connections.

Methods: A retrospective study was conducted at a private clinic from 2021 to 2023, involving 13 patients who underwent delayed single implant placement in both maxillae and mandible. Three months after implant placement, the buccal soft tissue adjacent to the abutment was augmented with VCMX. Intraoral scans were taken at three points: at implant placement (baseline), one-month post-grafting, and 24 months after implant loading. Pre-implant cone-beam computed tomography (CBCT) scans were also obtained. Volumetric and profilometric changes were measured at 1mm, 2mm, and 3mm below the mucosal margin by superimposing intraoral and CBCT scans. The Wilcoxon signed-rank test was used for statistical analysis.

Results: All 13 patients completed the two-year follow-up. Mean volumetric changes at the graft site were +18.15 ± 15.34 mm³ initially, decreasing by 11.73 ± 21.91 mm³ over two years. Profilometric analysis showed increases of 0.72 ± 0.88 mm, 0.54 ± 0.65 mm, and 0.32 ± 0.65 mm at 1, 2, and 3 mm, respectively, one-month post-grafting. At 24 months, reductions of -0.17 ± 0.77 mm, -0.45 ± 0.58 mm, and -0.48 ± 0.60 mm were recorded.

Conclusions: VCMX use for soft tissue augmentation shows minimal remodeling after 24 months, supporting its efficacy for soft tissue stability in dental implantology. Further long-term studies are recommended.