Oral leukoplakia and other white lesions of the oral mucosa related to dermatological disorders

“White lesions” of the oral mucosa often present problems of differential diagnosis, which are of primary importance when assessing precancerous changes in the mouth. The precancerous character of oral leukoplakia is well established, and the “high‐risk” type: erosive‐dysplastic leukoplakia of greater malignant potential, has been thoroughly investigated. Because of their possible association with oral carcinoma, some clinical types of oral lichen planus, namely, the atrophic erosive forms, indicate caution in their treatment and supervision. Epithelial dysplasia is often associated with candidiasis and discoid lupus erythematosus, but neither these, nor such other white lesions as white sponge naevus or morsicatio buccarum, are considered to be preneoplastic. All these white lesions may be clearly identified, differentiated, and circumscribed as clinico‐pathological disease‐entities, by clinical, histopathological and ultrastructural methods, thus facilitating early diagnosis, treatment and prevention of possible malignancy.