Effects of CGF and Collagen Fleece on Palatal Donor Site Healing: A Randomized Clinical Trial

Autogenous soft tissue grafts harvested from the palatal mucosa remain the gold standard for increasing keratinized tissue width and augmenting gingival thickness in periodontal and peri-implant plastic surgery. Despite their predictable clinical benefits, palatal donor sites frequently exhibit delayed epithelialization, postoperative bleeding, pain, and functional discomfort. These factors contribute to increased morbidity and may negatively affect patient compliance and overall satisfaction with periodontal treatment.

Recent biomaterials such as Concentrated Growth Factor (CGF) and collagen-based dressings have been proposed to enhance soft tissue regeneration and accelerate wound healing. CGF is produced by centrifugation of autologous blood and contains a dense fibrin matrix enriched with platelets, leukocytes, and growth factors. Its biological profile has been associated with improved angiogenesis, fibroblast migration, and soft-tissue remodeling. Collagen fleece (CF), a widely used resorbable matrix, provides hemostasis, a physical barrier for wound protection, and a scaffold that supports early epithelial migration. However, the comparative clinical efficacy of CGF and CF on palatal donor site healing has not been clearly established in controlled human studies.

This randomized controlled clinical trial was designed to evaluate the effects of CGF and CF on wound healing dynamics, preservation of palatal tissue thickness, and postoperative morbidity following standardized soft tissue graft harvesting. Thirty-eight systemically healthy adult patients requiring autogenous grafts were included and allocated to one of three groups: CGF, CF, or control. In the test groups, either CGF or CF was applied to the donor site, stabilized with sutures, and covered with an oral wound dressing. In the control group, a collagen sponge was placed beneath the wound dressing. All groups received identical postoperative care.

Primary and secondary outcome measures included changes in palatal tissue thickness, wound healing scores, epithelialization patterns, patient-reported pain levels, analgesic consumption, bleeding, and oral health-related quality of life. Tissue thickness was evaluated at baseline and at 1, 3, and 6 months postoperatively. Wound healing characteristics were recorded on postoperative days 3, 7, and 14, and at 1 month, using standardized indices such as the H₂O₂ bubbling test, the Modified Manchester Scar Scale, and the Landry-Turnbull-Howley healing index. Pain intensity and functional discomfort were assessed using visual analog scales (VAS), while overall patient impact was measured with the OHIP-14 questionnaire.

The central hypothesis of this study was that both CGF and CF would enhance palatal donor site healing relative to spontaneous healing, and that CGF would demonstrate additional benefits due to its autologous biological activity. The findings of this trial are expected to provide clinicians with evidence-based guidance on the use of supportive biomaterials to reduce postoperative morbidity, improve patient comfort, and optimize regenerative outcomes after periodontal soft-tissue grafting procedures.

Inclusion criteria

• Age ≥18 years
• Systemically healthy individuals
• Good oral hygiene
• Stable periodontal condition
• Indication for mucogingival surgery requiring autogenous soft tissue grafting
• Free gingival graft or de-epithelialized free gingival graft combined with either a coronally advanced flap or tunnel technique

Exclusion criteria

• Smoking
• Pregnancy or lactation
• Systemic diseases affecting wound healing
• Use of medications known to interfere with healing
• History of radiotherapy or chemotherapy
• Poor oral hygiene or uncontrolled periodontal disease
• Concomitant bone surgery or implant placement
• Surgical duration exceeding 2 hours