[Naevus spongiosus albus mucosae. Review and personal observations]

White sponge nevus of the mucosa is a rare, mostly verifiable hereditary ectodermal dysplasia of the mucous membranes. Because associated symptoms of the skin are missing, it is classified as a distinctive disease among the congenital leukokeratoses. In the most cases the symptomless mucosal lesions are detected by dentological examination though they are present at birth or appear in the first years of life. On the basis of three own observations clinical appearance, histopathology, electronmicroscopy and differential diagnosis are discussed.