This single-blind randomized controlled clinical trial aimed to compare the effects of hypochlorous acid, hyaluronic acid, and chlorhexidine mouthrinses on palatal donor site healing following free gingival graft surgery. Fifty-four patients requiring free gingival graft surgery were randomly assigned to one of three mouthrinse groups. Clinical wound healing, wound dimensions, epithelialization, tissue consistency, bleeding control, and postoperative pain were evaluated during a 28-day follow-up period. The findings of this study may contribute to the identification of an effective postoperative mouthrinse for improving palatal donor site healing and patient comfort.

Free gingival graft (FGG) surgery is a well-established periodontal procedure for increasing the width of keratinized tissue. Healing of the palatal donor site is often associated with postoperative pain and patient discomfort. Various mouthrinses have been proposed to improve wound healing and reduce postoperative symptoms; however, evidence comparing hypochlorous acid, hyaluronic acid, and chlorhexidine is limited.

This single-blind, parallel-group, randomized controlled clinical trial was conducted to compare the effects of hypochlorous acid, hyaluronic acid, and chlorhexidine mouthrinses on palatal donor site healing following FGG surgery. Fifty-four participants requiring FGG surgery were randomly allocated to one of three intervention groups. Clinical assessments included wound dimensions, wound healing index, epithelialization, tissue consistency, bleeding control, and postoperative pain using a visual analogue scale. Participants were followed for 28 days after surgery. The primary objective was to evaluate the effect of each mouthrinse on palatal donor site healing and postoperative recovery.

Inclusion Criteria:

• Age between 18 and 55 years.
• Indication for free gingival graft surgery to increase keratinized tissue width.
• Systemically healthy individuals.
• Palatal donor site suitable for graft harvesting.
• No history of periodontal surgery within the previous six months.
• Ability and willingness to comply with postoperative instructions and follow-up visits.
• Provision of written informed consent.

Exclusion Criteria:

• Systemic diseases that could affect wound healing.
• Smoking.
• Antibiotic use within the previous six months.
• Pregnancy or lactation.
• Known hypersensitivity to chlorhexidine, hypochlorous acid, hyaluronic acid, or any component of the study products.
• Active oral infection, periodontal abscess, or poor oral hygiene.
• Previous palatal surgery, mucosal lesions, anatomical limitations, or conditions affecting hemostasis at the donor site.
• Inability or unwillingness to comply with the study protocol.

Individual participant data (IPD) will not be shared because participant consent for public data sharing was not obtained at the time of enrollment, and the dataset contains information that could potentially compromise participant confidentiality.

The clinical examiner responsible for all outcome assessments was blinded to treatment allocation throughout the study. Participant blinding was not feasible because the mouthrinses differed in packaging, appearance, and taste. All clinical measurements were performed by the same blinded examiner.