Corresponding author: Dr. Herald J Sherlin Senior Lecturer, Department of Oral and Maxillofacial Pathology College of Dental Surgery Saveetha University 162, P H Road, Velappanchavadi, Chennai - 600077, Tamilnadu, India E-mail: drherald888@rediffmail.com Key words: gingiva, lichen sclerosus, mucous membrane J Dermatol Case Rep 2010 3, pp 38-43 Abstract Background: Lichen sclerosus is a chronic muco-cutaneous inflammatory dis- order of uncertain etiology. The prevalence of lichen sclerosus affecting only the oral mucosa is extremely rare and only 26 cases with histologically verified oral lichen sclerosus have been reported. Main observations: A 60-year-old man was referred to our hospital for com- plaints of white lesions in the oral cavity, which was otherwise asymptomatic and did not have any cutaneous or anogenital lesions. Clinical examination re- vealed white patches with reddish areas on the buccal mucosa bilaterally and on the maxillary posterior gingiva. Microscopic analysis of the lesion showed atrophied epithelium with basal cell degeneration, hyalinized connective tissue stroma with minimal chronic inflammatory cell infiltrate. Verhoeff’s staining re- vealed scantiness of elastic fibers in the connective tissue stroma. On the basis of these histological findings, the final diagnosis was given as Lichen Sclerosus. LS is rare in the oral cavity, particularly in the absence of simultaneous cutaneous and anogenital lesions. Conclusions: Only 7 cases of oral LS have been reported involving the gingiva. To our knowledge, this is the eigth case to be reported with gingival involve- ment and the first case to be reported with bilateral involvement of buccal mu- cosa and gingiva. Lichen sclerosus of the oral cavity. Case report and review of literature. Herald Justin Sherlin, Karthikeyan Ramalingam, Anuja Natesan, Pratibha Ramani, Priya Premkumar, Chandrasekar Thiruvenkadam Department of Oral and Maxillofacial Pathology, College of Dental Surgery, Saveetha University, Chennai, Tamil Nadu, India. Introduction Lichen sclerosus (LS) is a chronic muco-cutaneous inflam- matory disorder, preferentially affecting the skin and the ge- nitals. 1 LS may occur in adults of all races and is five to ten times more common in females than in males. 2 The under- lying etiology remains obscure, although various infections, trauma, genetic factors, hormonal and auto-immune rela- ted disorders have been theorized. 2 Skin lesions of LS are clinically characterized by flat, stiff, shiny, porcelain white, polygonal papules that coalesce to form plaques. Most of the skin lesions are generally confi- ned to the neck and trunk and are usually asymptomatic, al- though pruritus may occur. 3 LS tends to affect the skin of the anogenital region and are characterized by areas of pallor. In contrast to LS of the skin, which rarely itches, there is often severe pruritus in the le- sions involving vulvar region, which may lead to erosions and purpura. In men, the foreskin and glans penis are usually affected and often result in phimosis. 3 Oral lesions of LS are rare and occur with or without le- sions of the skin or vulva. Oral mucosal lesions appear as well demarcated, ivory or whitish, flat lesions similar to those seen in vulva but striae, erosions and ulcers clinically in- distinguishable from lichen planus are also seen. The buc- cal, labial and palatal mucosa are the most common intra- oral sites affected and the sex distribution is almost equal with no racial preferences. 4-10 Histopathology of oral LS is characterized by gradual atro- phic epithelium, subepithelial homogenization and hyalini- zation of the collagen fibers with an underlying band like lymphocytic inflammatory infiltrate. Hyperkeratosis may be absent in oral lesions but is always present in skin lesions. 3 Treatment of oral LS consists of topical corticosteroids or excision. Treatment is unnecessary, if the patient is asymptomatic. 3 DOI: 10.3315/jdcr.2010.1052 38