Analysis of the efficacy of photobiomodulation therapy in the treatment of oral lichen planus: A systematic review and meta-analysis of randomized and non-randomized clinical trials.

Background: Oral lichen planus (OLP) is a chronic autoimmune disease that negatively affects patients' quality of life through symptoms such as pain, irritation, bleeding, and ulceration. Despite numerous therapeutic approaches, there is no definitive cure, and conventional corticosteroid therapy is often associated with prolonged use and adverse effects. Photobiomodulation therapy (PBMT) has emerged as a promising non-invasive alternative with no reported side effects. This systematic review aimed to evaluate the efficacy of PBMT in the treatment of OLP. Materials and Methods: Electronic searches were conducted in PubMed, LILACS, Livivo, Scopus, Embase, Web of Science, and EBSCO up to March 1, 2025. Randomized and non-randomized clinical trials involving human participants were included, comparing PBMT with conventional pharmacological therapy. Risk of bias was assessed using the Cochrane tools, and the certainty of the evidence was evaluated using the GRADE approach. Results: A total of 4,118 studies were identified, and 15 met the inclusion criteria after screening. Meta-analysis showed that PBMT slightly reduced pain levels compared with conventional therapy but did not significantly affect disease severity or anxiety scores. However, PBMT was associated with higher rates of complete mucosal healing and lower recurrence rates in patients with erosive OLP. Conclusions: PBMT appears to be a safe and effective therapeutic alternative for the management of OLP, particularly by reducing pain, promoting mucosal healing, and decreasing lesion recurrence. These findings support its potential role in clinical practice, although further high-quality randomized clinical trials are warranted to strengthen the current evidence.