Oral lichen planus – an oral potentially malignant disorder (OPMD) of the oral cavity

Introduction. Oral lichen planus is a chronic inflammatory disease of unknown etiology, characterized by recurrent lesions, presenting as reticular lesions, sometimes accompanied by atrophic, erosive, and/or ulcerative areas. Despite being one of the most common conditions affecting the oral mucosa, oral lichen planus remains an ailment with undefined etiology and unclear pathogenesis, imprecise management, and uncertain premalignant potential. Materials and methods. A narrative literature review study was conducted. A bibliographic search was carried out in databases such as PubMed, Hinari, SpringerLink, the National Center of Biotechnology Information, and Medline. Articles published from 1990 to 2023 were selected using various combinations of keywords: “oral lichen planus,” and “epidemiology,” “etiology,” “pathogenesis,” “symptoms,” “management,” “histopathology,” and “malignant transformation.” After processing the data from these databases, 475 full articles were found. The final bibliography comprised 50 relevant sources, considered representative of the materials published on the topic of this synthesis article. Results. Oral lichen planus is an inflammatory condition associated with T-cell-mediated immune dysfunction. Triggers include autoimmune responses to local antigens, microorganisms, and stress. The disease results from a complex interplay of host factors, lifestyle, and environmental factors leading to T-cell-mediated immune dysregulation. Diagnosis of oral lichen planus is based on clinical features (multiple, bilateral, symmetrically distributed lesions, occurring most commonly on the buccal mucosa, dorsal tongue surface, and gingiva), histopathological findings (predominantly lymphocytic bandlike infiltrate in the lamina propria, presence of apoptotic cells in the basal cell layer, absence of epithelial dysplasia), and immune-related changes (deposition of fibrinogen along the basement membrane zone, presence of granular fluorescent deposits containing IgA, IgG, and IgM in colloid bodies). Conclusions. Oral lichen planus is a chronic inflammatory condition mediated by T-cells in response to various extrinsic antigens, modified autoantigens, or superantigens, with periods of remission and relapse and the potential for malignant transformation. The etiology and pathogenesis of this condition are complex, diagnosis relies on clinical features, histopathological findings, and immunological data, patient treatment is symptomatic, and the potential for malignant transformation varies. Nevertheless, prospective studies with large sample sizes, adequate treatment duration, and long-term follow-up are needed.