This randomized controlled clinical trial aims to evaluate the biomodulatory effects of a 940-nm GaAlAs diode laser on postoperative pain control and wound healing at the palatal donor site following free gingival graft harvesting. Adult patients undergoing free gingival graft surgery will be randomly allocated to receive either a single session of adjunctive diode laser irradiation immediately after surgery or conventional postoperative care alone. Postoperative pain will be assessed using a visual analog scale, while clinical parameters related to wound healing, including bleeding tendency, epithelialization, and wound size reduction, will be evaluated at predefined follow-up time points. The findings of this study may contribute to the clinical understanding of photobiomodulation in free gingival graft surgery.

Inclusion Criteria:

1. ≥18 years of age;
2. systemically healthy individuals without any conditions that could affect wound healing (e.g., diabetes, immunosuppression, coagulation disorders, Candida infection;
3. full-mouth plaque score (FMPS) and full-mouth bleeding score (FMBS) <15%;
4. no previous history of palatal tissue harvesting;
5. no use of overdentures or partial dentures covering the donor area.

Exclusion Criteria:

1. pregnant or breastfeeding women;
2. smokers;
3. patients with psychiatric disorders; and
4. patients taking any medications that impair tissue healing and affect pain perception.

Periodontal surgeries are performed by a periodontist with more than 20 years of clinical experience, who is not involved in laser irradiation or clinical outcome assessment. Laser irradiation and digital scanning of the palatal wound area are performed by a trained investigator who does not participate in clinical outcome evaluation. Clinical assessments and measurements of scanned images are conducted by an independent periodontist who is blinded to group allocation.