Dental histology in familial expansile osteolysis.

The dental histopathology is described of patients suffering from Familial Expansile Osteolysis (FEO), a rare and unique autosomal dominant disease which has severe bony as well as dental consequences. The predominant dental features are resorption of the cervical and apical regions of the roots, premature depositions both of irregular secondary dentin, which causes narrowing of the pulp cavities, and of cellular cementum, which causes patchy narrowing of the periodontal ligament. The dental pulp shows age-like changes, including multiple pulp stones and the ligament vasculature appears to be abnormal. Evidence for involvement of enamel is equivocal. This combination of dental effects together with the bony lesions distinguishes the disease from idiopathic external resorption of either the single or multiple kind, despite similarities in the histopathology of the resorptive lesions; and from other non-hereditary and hereditary osteolytic diseases.