Efficacy of photodynamic therapy versus corticosteroid therapy for oral lichen planus: a systematic review and meta-analysis

Oral lichen planus (OLP) is one of the most common non-infectious oral mucosal diseases. Currently, corticosteroid therapy (CST) is regarded as the first-line treatment for OLP, however, long-term use of CST may lead to adverse effects and be ineffective for a minority of patients. Objectives: To systematically evaluate the efficacy of photodynamic therapy (PDT) versus CST in the treatment of OLP. A comprehensive search was conducted in Chinese- and English-language electronic databases, including China National Knowledge Infrastructure, Wanfang Data, VIP, PubMed, Embase, and the Cochrane Library, for studies that compared the efficacy of PDT and CST, with the search timeframe set from the establishment of each database to October 2025. Data from eligible studies were analysed using Stata 15.0 software. In total,13 randomised controlled trials were included, involving 587 patients (296 in the PDT group and 291 in the CST group). Pooled analysis revealed no statistically significant differences between the two groups in the total effective rate for OLP treatment or in the improvement in Visual Analogue Scale (VAS) score, Thongprasom (TH) sign score, or lesion area (all p>0.05). Subgroup analysis indicated that country and photosensitiser type were the sources of heterogeneity among the studies. Moreover, subgroup analyses revealed that in studies conducted in non-Chinese countries and in studies using phenothiazine dye-based photosensitisers (e.g. toluidine blue), CST showed significantly superior efficacy to PDT in improving VAS score, TH score, and lesion area (p<0.05). Current evidence indicates that PDT and CST have comparable efficacy in the treatment of OLP. This equivalence positions PDT as a viable non-steroidal alternative, particularly valuable for patients who are intolerant to, have contraindications against, or seek to avoid the local and systemic side effects associated with long-term corticosteroid use.