Effectiveness of Low-level Laser Therapy with or without Hyaluronic Acid Gel in Tissue Healing and Pain Control after Gingival Surgery: A Systematic Review

Abstract

Aims: This systematic review assessed the effectiveness of low-level laser therapy (LLLT), alone or combined with hyaluronic acid (HA), in enhancing tissue healing and reducing postoperative pain after gingival surgery. Study Design: Systematic review of randomized controlled trials (RCTs), conducted according to PRISMA 2020 guidelines, and utilizing the SWiM (Synthesis Without Meta-analysis) approach for narrative synthesis. This methodological decision was made due to the substantial anticipated clinical and methodological heterogeneity among the included RCTs, which is further detailed in the methodology section. Place and Duration of Study: This review was carried out between between August 1 and November 12, 2025. Methodology: Randomized controlled trials evaluating adult patients (≥18 years) undergoing gingival surgical procedures and receiving postoperative LLLT, HA gel, or their combined application were eligible for inclusion. Searches were carried out in EMBASE, LILACS, PubMed, SCOPUS, Web of Science, The Cochrane Library, and additional gray literature sources. Risk of bias was assessed using the Cochrane RoB 2.0 tool. Due to clinical and methodological heterogeneity related to laser parameters, HA formulations, application protocols, and outcome assessment methods, the synthesis followed a narrative approach without meta-analysis. Three studies met the eligibility criteria, comprising a total of 116 participants. Results: Postoperative pain showed an average reduction of approximately 30% within 48–72 hours, with the greatest reductions observed with combined LLLT and HA1. Regarding soft tissue healing, modest early improvements were observed with the combined approach, but these effects were not sustained over time, and two of three trials reported no significant long-term differences. Overall, the certainty of the evidence remains low due to small samples, risk of bias, and heterogeneity among studies. Conclusion: The combined application of LLLT and HA demonstrates potential to enhance early soft tissue healing and reduce postoperative pain following gingival surgery. However, due to the limited number of RCTs and methodological weaknesses identified, the certainty of the evidence remains low. Further well-designed RCTs with standardized protocols are necessary to substantiate these findings.