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

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.

Participants in this group will receive root coverage surgery using a volume-stable xenogeneic collagen matrix associated with a coronally advanced flap.

Device: Volume-stable xenogeneic collagen matrix (VCMX)

Participants in this group will receive root coverage surgery using an autogenous subepithelial connective tissue graft associated with a coronally advanced flap.

Procedure: Subepithelial connective tissue graft (SCTG)

A volume-stable xenogeneic collagen matrix will be used as a soft-tissue substitute for root coverage surgery. The matrix will be placed over the recession defects and covered by a coronally advanced flap.

An autogenous subepithelial connective tissue graft will be harvested from the palate and used for root coverage surgery. The graft will be placed over the recession defects and covered by a coronally advanced flap.

Plazo: Baseline, 3 months, 6 months, and 12 months

Gingival recession depth will be measured clinically in millimeters as the distance from the cementoenamel junction to the gingival margin. The main comparison between groups will be performed at 12 months.

Plazo: Baseline, 3 months, 6 months, and 12 months

Gingival recession width will be measured horizontally in millimeters at the level of the cementoenamel junction.

Plazo: Baseline, 3 months, 6 months, and 12 months

Keratinized tissue width will be measured in millimeters from the gingival margin to the mucogingival junction.

Plazo: Baseline, 3 months, 6 months, and 12 months

Gingival thickness will be measured in millimeters at the treated sites using a standardized clinical method.

Plazo: Baseline, 3 months, 6 months, and 12 months

Probing depth will be measured in millimeters from the gingival margin to the bottom of the sulcus or pocket at the treated sites.

Plazo: Baseline, 3 months, 6 months, and 12 months

Clinical attachment level will be calculated in millimeters as probing depth plus gingival recession depth.

Plazo: 3 months, 6 months, and 12 months

Percentage of root coverage will be calculated based on the reduction in gingival recession depth from baseline to 12 months.

Plazo: 3 months, 6 months, and 12 months

Complete root coverage will be defined as the absence of residual gingival recession at the treated site.

Plazo: Baseline, 3 months, 6 months, and 12 months

Will be assessed after standardized air stimulation using a 0 to 100 visual analog scale. A score of 0 indicates no pain or sensitivity, and a score of 100 indicates the worst imaginable pain or sensitivity. Higher scores indicate worse dentin hypersensitivity.

Plazo: Baseline, 3 months, 6 months, and 12 months

Patient-reported esthetic satisfaction will be assessed using a 0 to 100 visual analog scale. A score of 0 indicates complete dissatisfaction, and a score of 100 indicates complete satisfaction. Higher scores indicate better esthetic satisfaction.

Plazo: Baseline, 3 months, 6 months, and 12 months

Soft tissue volumetric changes will be assessed using intraoral scans and digital superimposition of three-dimensional Standard Tessellation Language (STL) models.

Plazo: 7 days, 14 days, and 30 days

Early wound healing will be assessed clinically during the postoperative period based on flap margin adaptation, suture stability, edema, inflammation, erythema, fibrin accumulation, tissue necrosis, epithelialization, biomaterial or graft exposure, and overall wound healing pattern.

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