Using monoclonal antibodies, we performed immunohistochemical investigations of the expression of alpha 2, alpha 3 and beta 4 integrin subunits within the squamous epithelial linings of odontogenic cysts. Tissue samples consisted of both follicular cysts and odontogenic keratocysts from 15 patients. It was found that beta 4 integrin was expressed on the basement membrane regardless of the histological type of the cyst. The degree of immunostaining for alpha 2 and alpha 3 integrin expression corresponded to the thickness of the epithelial cyst wall. We found that the thickness of the epithelial lining of odontogenic cysts had a direct correlation with the expression of integrin molecules.