Oral lichen planus (OLP) is a common chronic inflammatory disease of the oral mucosa and is considered a precancerous condition. It is characterized by white reticular changes in the oral mucosa, which can progress to erosions and cause pain in severe cases. The pathogenesis of OLP is still unclear, but it is believed to be a T-lymphocyte-mediated autoimmune disease. Currently, only symptomatic treatments are available, and there is no definitive cure.

In this project, we plan to use TCM differentiation to categorize OLP patients and conduct a randomized controlled clinical trial to demonstrate the enhanced therapeutic effect of paeoniflorin combined with photodynamic therapy for OLP. The implementation of this project will provide new insights into the clinical management of OLP, improve our understanding of the treatment mechanisms, and have important theoretical and clinical implications.

Paeoniflorin, a compound extracted from the traditional Chinese medicine, has anti-inflammatory and immunomodulatory effects. Photodynamic therapy is a novel local treatment approach, where photosensitizers selectively target and destroy diseased cells. Both treatments have shown efficacy in treating OLP when used individually.

Inclusion Criteria:

• patients with oral lichen planus
• male or female patients older than 18 years of age
• patients willing to participate with signed informed consent.

Exclusion Criteria:

• pregnant or lactating
• had serious systemic diseases of the heart, lung, liver, and kidney, or had tumors
• were unwilling to participate in the experiment.