Reactive hyperplasias,precancerous and malignant lesions of the oral mucosa.

The oral cavity contains many organs and tissues compressed in a small area. Accordingly oral tumors have a wide variety of appearances. Reactive hyper-plastic lesions include epulis,morsicatio,traumatic ulcer or palatal hyperplasia. These benign lesions must be separated clinically and histologically from precancerous and neoplastic lesions. In leukoplakia,the individual risk can be estimated by clinical signs. Nevertheless histopathology is mandatory because precancerous lesions usually precede or accompany most oral cancers. Amalgam tattoo,oral nevi and melanoacanthoma have to be considered as differential diagnoses of oral melanoma. Accurate clinico-pathological diagnosis is mandatory to insure appropriate therapy. Oral soft tissue tumors such as Kaposi sarcoma and multiple mucosal neuromas in MEN 2b require interdisciplinary management. Diseases affecting the minor salivary glands which may be encountered by dermatologists include mucocele, necrotizing sialometa-plasia,and tumors such as pleomorphic adenoma.