Peri-Implant Soft-Tissue Augmentation Using Xenogeneic Collagen Matrices Versus Autogenous Connective Tissue Grafts in Single-Tooth Implants: a Systematic Review

Objectives: The aim of this systematic review was to evaluate and compare the clinical outcomes of peri-implant soft tissue augmentation using xenogeneic collagen matrices and autogenous subepithelial connective tissue grafts in single-tooth implant therapy. The review focused on key clinical parameters, including marginal bone loss, soft tissue thickness gain, mid-buccal recession, and aesthetic outcomes assessed by the pink aesthetic score.

Material and Methods: This systematic review was conducted following PRISMA guidelines. A comprehensive electronic search was performed in MEDLINE (PubMed), ScienceDirect, and the Cochrane Library for studies published between November 18, 2015, and November 18, 2025. Eligible studies included randomized controlled trials, prospective clinical trials, and cohort studies evaluating peri-implant soft tissue augmentation using xenogeneic collagen matrices compared with autogenous subepithelial connective tissue grafts. Study quality and risk of bias were assessed using the Joanna Briggs Institute Critical Appraisal Checklist.

Results: A total of 839 records were identified, of which six studies met the inclusion criteria. Both treatment modalities demonstrated favourable clinical outcomes. Marginal bone loss was generally limited, with no consistent statistically significant differences between groups, although one study reported greater bone loss in the xenogeneic group. Soft tissue thickness gain showed a trend favouring autogenous grafts. Mid-buccal recession data were limited but suggested slightly greater recession in the xenogeneic group. Aesthetic outcomes were comparable between groups.

Conclusions: Both treatment modalities are effective; however, autogenous grafts provide more consistent soft tissue thickness gain, while collagen matrices represent a viable alternative with comparable aesthetic and bone outcomes.

J Oral Maxillofac Res 2026;17(2):e2

doi: 10.5037/jomr.2026.17202

Accepted for publication: 29 June 2026

Keywords: bone resorption; collagen; connective tissue; dental esthetics; dental implants; endosseous dental implantation.