The purpose of this 2-year longitudinal clinical study was to investigate alveolar (oral) bone height and density changes in osteoporotic/osteopenic women compared with women with normal lumbar spine bone mineral density (BMD). Thirty-eight postmenopausal women completed this study; 21 women had normal BMD of the lumbar spine, while 17 women had osteoporosis or osteopenia of the lumbar spine at baseline. All subjects had a history of periodontitis and participated in 3- to 4-month periodontal maintenance programs. No subjects were current smokers. All patients were within 5 years of menopause at the start of the study. Four vertical bitewing radiographs of posterior sextants were taken at baseline and 2-year visits. Radiographs were examined using computer-assisted densitometric image analysis (CADIA) for changes in bone density at the crestal and subcrestal regions of interproximal bone. Changes in alveolar bone height were also measured. Radiographic data were analyzed by the t-test for two independent samples. Osteoporotic/osteopenic women exhibited a higher frequency of alveolar bone height loss (p<0.05) and crestal (p<0.025) and subcrestal (p<0.03) density loss relative to women with normal BMD. Estrogen deficiency was associated with increased frequency of alveolar bone crestal density loss in the osteoporotic/osteopenic women and in the overall study population (p<0.05). These data suggest that osteoporosis/osteopenia and estrogen deficiency are risk factors for alveolar bone density loss in postmenopausal women with a history of periodontitis.