Clinical and Histological Evaluation of Subepithelial Connective Tissue Graft Maturation at Different Healing Timepoints, With and Without Topical Application of a Polynucleotide- and Hyaluronic Acid-Based Gel

This study evaluates whether a 9-week healing interval is sufficient for subepithelial connective tissue graft (SCTG) maturation after palatal harvesting, and whether topical application of a polynucleotide and hyaluronic acid gel (Regenfast®) improves tissue quality. This is a randomized, blinded, controlled clinical trial with a split-mouth design involving 15 participants. Each participant undergoes bilateral SCTG harvesting from the palate in two surgical sessions 9 weeks apart. In the first session, one randomized side receives a single topical application of Regenfast® after graft removal; the contralateral side serves as control. Standardized tissue fragments (3×3 mm, 1.5 mm thickness) are collected from each graft for histological (HE, Picrosirius Red) and immunohistochemical analyses. Comparisons are made between grafts collected at baseline and after 9 weeks, and between sides treated with or without the gel.

Inclusion Criteria: * Age between 18 and 60 years * Good general systemic health * Presence of multiple bilateral gingival recessions with indication for root coverage Exclusion Criteria: * Smoking of any intensity * Pregnancy or lactation * Oral lesions or alterations in the palatal mucosa * Previous history of graft harvesting from the donor area * Continuous use of medications that interfere with the inflammatory response, such as corticosteroids or immunosuppressants * Autoimmune diseases, coagulation disorders, or other systemic conditions affecting wound healing