Volume-Stable Collagen Matrix Versus Subepithelial Connective Tissue Graft for Multiple Gingival Recessions

Volume-Stable Xenogeneic Collagen Matrix Versus Subepithelial Connective Tissue Graft for the Treatment of Multiple Gingival Recessions: A 12-Month Randomized Controlled Clinical Trial

Gingival recession is a clinical condition in which the gingival margin is displaced apically, exposing the root surface. This condition may be associated with esthetic concerns, dentin hypersensitivity, and difficulties in oral hygiene. Subepithelial connective tissue grafting is considered a standard surgical approach for root coverage, but it requires harvesting tissue from the palate, which may increase postoperative discomfort. Volume-stable xenogeneic collagen matrices have been proposed as an alternative biomaterial to reduce the need for a palatal donor site.

This randomized controlled clinical trial will compare a volume-stable xenogeneic collagen matrix with an autogenous subepithelial connective tissue graft for the treatment of multiple gingival recessions. Participants will be allocated to one of two treatment groups. The test group will receive root coverage surgery using a volume-stable collagen matrix, while the control group will receive root coverage surgery using a subepithelial connective tissue graft. Clinical, patient-reported, esthetic, and digital outcomes will be assessed at baseline and during follow-up visits up to 12 months.

The primary outcome will be the change in gingival recession depth from baseline to 12 months. Secondary outcomes will include keratinized tissue width, gingival thickness, percentage of root coverage, complete root coverage, dentin hypersensitivity, patient-reported satisfaction, early wound healing, and digital volumetric changes assessed by intraoral scanning.

This study is a randomized controlled clinical trial designed to evaluate the clinical performance of a volume-stable xenogeneic collagen matrix compared with an autogenous subepithelial connective tissue graft in the treatment of multiple gingival recessions.

Eligible participants presenting multiple gingival recessions will be recruited and allocated to one of two parallel treatment groups. In the test group, participants will receive root coverage surgery using a volume-stable xenogeneic collagen matrix associated with a coronally advanced flap. In the control group, participants will receive root coverage surgery using an autogenous subepithelial connective tissue graft associated with a coronally advanced flap.

Clinical assessments will include gingival recession depth, keratinized tissue width, probing depth, clinical attachment level, gingival thickness, percentage of root coverage, and complete root coverage. Patient-reported outcomes will include dentin hypersensitivity, postoperative comfort, esthetic satisfaction, and acceptance of the procedure. Standardized clinical photographs and intraoral scans will be obtained during follow-up. Digital analyses will be used to assess changes in soft tissue volume over time.

The primary endpoint will be the change in gingival recession depth from baseline to 12 months. Secondary endpoints will include clinical, esthetic, patient-reported, wound healing, and digital volumetric outcomes assessed at predefined follow-up visits.

Inclusion Criteria:

• Adults aged 18 years or older.
• Presence of at least two Cairo RT1 gingival recessions in anterior teeth and/or premolars.
• Gingival recession depth greater than or equal to 2 mm.
• Presence of at least 2 mm of keratinized gingiva apical to the gingival recession.
• Indication for root coverage treatment due to esthetic concern and/or dentin hypersensitivity.
• Sites with non-carious cervical lesions may be included if they are previously restored and, after restoration, present residual gingival recession greater than or equal to 2 mm.
• Good plaque control, defined as full-mouth plaque score and full-mouth marginal gingival bleeding score below 20%.

Exclusion Criteria:

• Current smokers or individuals who stopped smoking less than 12 months before enrollment.
• Decompensated systemic diseases.
• Pregnancy or lactation.
• Active periodontal disease.
• Untreated root caries.
• Previous mucogingival surgery in the study area.