Effects of Hyaluronic Acid in the Surgical Treatment of Periodontitis: A Systematic Review.

PURPOSE: Hyaluronic acid (HA) is a naturally occurring polymer synthesised endogenously in the human body, with distinctive physicochemical and biological properties such as excellent biocompatibility and biodegradability. These characteristics have led to extensive research into its therapeutic potential, particularly in the management of inflammatory diseases. This systematic review aimed to evaluate the effects of HA on clinical outcomes in the surgical treatment of periodontitis. METHODS AND MATERIALS: This review was registered with PROSPERO (CRD42024493296) and conducted according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 guidelines. A systematic search was performed in PubMed, Cochrane, and Scopus up to September 2025. Randomised controlled trials assessing HA clinical outcomes in the surgical treatment of periodontitis were included. RESULTS: Nine RCTs including a total of 343 patients were analysed. Sample sizes ranged from 14 to 60 participants, with follow-up periods between 3 and 24 months. The adjunctive use of HA in the surgical treatment of periodontitis led to consistent improvements, with probing depth (PD) reductions of 2.0-3.5 mm and CAL gains of 2.0-3.8 mm after 6-12 months. Radiographic evaluations also showed greater bone fill in intrabony defects. CONCLUSION: Within the limits of available randomised controlled trials, HA shows potential as an adjunct in the surgical management of periodontitis. Although reported improvements in clinical parameters are encouraging, evidence remains heterogeneous and requires confirmation through standardised, long-term studies.