oral lesions as a clue in diagnosis of some skin and systemic diseases

Summary and Conclusion: The oral cavity, the part of entry into digestive system is of great importance in diagnosis of many skin and systemic diseases. Oral mucous membrane lesions represent a challenge for both dermatologists and dentists The oral lesions represent :lt diagnostic problems but the advent of modern techniques of diagnosis in the form of electron microscopy, immunoelectron microscopy, direct and indirect immunoflourescence and other modern molecular techniques made the diagnosis of oral lesions more easy and reliable. The oral cavity is lined by the oral mucosa which forms a primary structural barrier between the internal and external environments. It <prevents the entry of noxious substances or organisms and loss of fl uids. The integrity of the oral mucosa is maintained through its superficial layers, which limit the penetration of these harmful agents. The basic structure of normal oral mucosa and the mechanisms by which normal function is maintained is important in understanding the various oral soft tissue lesions that occur in the mouth. The oral epithelium is of stratified squamous variety. It is composed principally of one cell type, the keratinocyte which is organised into multiple layers or strata which vary with the location of the oral mucosa depending 011 the degree and type of keratinization. In addition to these cells a minority of population of non keratinocytes reside in the epithelium. These include 131