Effectiveness of Low-Level Laser Therapy in Reducing Pain Score and Healing Time of Recurrent Aphthous Stomatitis: A Systematic Review and Meta-Analysis

Abstract Background: Recurrent aphthous stomatitis (RAS) is a common chronic inflammatory oral disease which negatively impacts the quality of life. Current therapies aim to reduce pain and healing process yet challenges such as rapid loss due to salivary flushing in topical drugs and adverse effect due to prolonged use of systemic medications require further notice. Low-level laser therapy is reported with immediate pain relief and faster healing thus preserving potential for optimal treatment modalities. This review critically analyses and summarizes the effectiveness of LLLT in reducing pain score and healing time of RAS. Methods: A systematic search was conducted in ScienceDirect, PubMed, and Scopus using keywords of low-level laser therapy, photo-biomodulation therapy, and recurrent aphthous stomatitis. RCTs between 1967 to June 2022, presenting characteristics of laser and reporting pain score and/or healing time of RAS after irradiation were included. Animal studies and recurrent aphthous ulcer with a history of systemic condition were excluded. Studies were critically appraised using RoB 2 tool. A meta-analysis was performed using inverse variance random effects. Results: Fourteen trials with a total of 664 patients were included. Reduced pain was reported in 13 studies, while shortened healing time was presented in 4. The pooling of two studies after CO2 irradiation demonstrated faster healing time compared to placebo (MD: -3.72; 95% CI: -4.18, -3.25). Conclusion: Pain score and healing time of RAS were reduced after irradiation with LLLT. RoB resulted in “some concerns” urging well-designed RCTs with larger samples to further assess each laser application for comparison. Systematic review registration: PROSPERO CRD42022355737.