Effect of i-PRF and LLLT on Free Gingival Graft Shrinkage

This randomized controlled clinical trial investigates the effects of injectable platelet-rich fibrin (i-PRF) and low-level laser therapy (LLLT) on the shrinkage of free gingival grafts (FGG) used to treat gingival recession. Free gingival grafting is commonly performed to increase the width of keratinized tissue around teeth, but shrinkage during healing can reduce clinical outcomes.

The study included 48 systemically healthy adult patients with Cairo Class I gingival recession in mandibular anterior teeth. Participants were randomly assigned to one of three groups: control (FGG alone), i-PRF (FGG + platelet-rich fibrin), or LLLT (FGG + low-level laser therapy). Ethical approval was obtained from the Clinical Research Ethics Committee of Inonu University (Protocol No: 2024/84), and all participants provided written informed consent. The study protocol was registered at ClinicalTrials.gov (NCT06744270) and conducted according to CONSORT 2010 guidelines.

All patients received preoperative periodontal treatment, including plaque removal and oral hygiene instructions. Free gingival grafts were harvested from the palatal region and adapted to the recipient site, then stabilized with sutures. In the i-PRF group, autologous platelet-rich fibrin gel was applied to the graft surface. In the LLLT group, laser therapy was applied immediately after surgery and on postoperative days 3, 5, 7, and 14. The control group received no additional treatment beyond standard grafting.

Postoperative care included use of a periodontal dressing, chlorhexidine mouthwash, analgesics as needed, and oral hygiene instructions after suture removal. Clinical evaluations included gingival recession depth, keratinized tissue height, probing depth, clinical attachment level, and graft area measurements at baseline, 1, 3, and 6 months. Edema, erythema, and patient-reported pain were also assessed during follow-up.

The primary outcome of the study was graft shrinkage, calculated as the percentage decrease in graft area over time. Secondary outcomes included clinical parameters and patient-reported postoperative morbidity. All measurements were performed by calibrated, blinded examiners to ensure reliability.

Inclusion criteria

• Age > 18 years.
• Systemically healthy.
• Cairo Class I gingival recession in vital mandibular anterior incisors.
• No caries or restorations in the relevant teeth.
• Keratinized gingiva height < 2 mm in the included teeth.
• Plaque Index (PI) < 1.
• Gingival Index (GI) < 1.

Exclusion criteria

• Active periodontal disease or probing depth > 3 mm.
• Use of medications that could prevent surgery or affect wound healing.
• Pregnancy or breastfeeding.
• History of periodontal surgery in the working area.
• Active smokers.
• Current orthodontic treatment.