Premature alveolar bone loss in Erdheim-Chester disease. Erdheim-Chester disease is a rare histiocytosis also known as lipoid granulomatosis. Oral findings have not been reported previously to our knowledge. This case report documents evidence of oral sequelae of Erdheim-Chester disease. A patient whose course was followed for 10 years at the National Institutes of Health had premature alveolar bone resorption. He underwent full-mouth extraction at age 29 years because of severe periodontitis. Histopathologic evidence of Erdheim-Chester disease was demonstrated in the periodontal soft tissues. In the ensuring years, accelerated resorption of the residual ridges precluded the use of conventional dentures. We recommend early preventive dental management for patients with Erdheim-Chester disease. 