A study was conducted to determine whether radiographic changes could be detected in the mandible of patients with mild-to-moderate postmenopausal osteoporosis and whether these changes could be used as a diagnostic tool to differentiate normal from osteoporotic patients. Subjects were classified as either osteoporotic (21) or normal (14) on the basis of bone density measurements of the lumbar spine and femoral neck, as determined by dual-photon absorptiometry. Mandibular bone density measurements were made on panoramic and periapical radiographs and expressed in terms of millimeters of aluminum equivalent. Thickness of the cortex at the angle of the mandible, sinus floor, and lamina dura of the tooth socket was also measured. There were no significant differences in any of the mandibular measurements between the normal and osteoporotic subjects. Whereas the skeletal bone measurements were correlated with each other, there was no correlation between skeletal and mandibular bone measurements. Women with mild-to-moderate osteoporosis could not be distinguished from women with normal bone density with the method described in this article.