Etiopathogenesis of oral lichen planus: what do we know so far?

Abstract

Oral lichen planus (OLP) is a chronic inflammatory autoimmune disease classified by the World Health Organization (WHO) as a potentially malignant disorder. OLP affects the mucous membranes lining the oral cavity in different clinical patterns, with the classic appearance being described as bilateral white reticular lesions on the buccal mucosa and sides of the tongue. Periods of relapses and remissions characterize OLP, and symptomatic cases considerably reduce the patient's quality of life and are usually managed with corticosteroid therapy. The causes of OLP are not completely understood. The aim of this narrative review of the literature is to summarize the main aspects of the etiopathogenesis of OLP, with emphasis on recently proposed hypotheses for the immunological mechanisms involved in this lesion. The current body of evidence supports that the cause of OLP is multifactorial, involving immune, genetic and environmental factors that produce a response of CD8+ T cells against oral keratinocytes. This review concludes that the etiopathogenesis of OLP is an open field for new research, and its knowledge by the dentist allows the choice of appropriate therapies, as well as the implementation of a periodic monitoring scheme for the patient due to the potential for malignancy of the lesion.

Keywords: Lichen Planus, Oral; Lymphocytes; Carcinoma, Squamous Cell.