RESUMEN
Lichen sclerosus (LS) is a chronic inflammatory mucocutaneous disease that often affects the anogenital area; oral mucosal lesions are extremely rare. A 52-year-old woman presented for evaluation of an 8-year history of a persistent whitish plaque in the buccal mucosa. Intraoral examination revealed multiple elevated whitish plaques diffusely distributed in the buccal mucosa associated with an area of tissue atrophy. Although both leukoplakia and lichen planus were considered, incisional biopsy and later, full excision confirmed the histopathological diagnosis of oral LS. After 6 months of follow-up, there are no clinical signs of relapse. This case highlights the importance of clinical and histopathological findings for the correct diagnosis and treatment of oral LS.