Osteoporosis Screening by Panoramic Radiographs: Comparison with Osteoporosis Self-Assessment Tool

Objectives: Previous studies suggest that mandibular inferior cortical shape and width detected on panoramic radiographs may be associated with skeletal bone mineral density (BMD), increased risk of osteoporotic fractures and bone turnover in postmenopausal women. These measures may be useful screening tools for osteoporosis in postmenopausal women. The purpose of this study was to clarify whether these measures are validated compared to simple screening tools based on questionnaire such as Osteoporosis Self-assessment Tool (OST) (Koh et al., Osteoporos Int, 2001) in postmenopausal women. Methods: We calculated the diagnostic performances of panoramic radiographic measures and OST for identifying women with osteoporosis in 387 postmenopausal women (mean age+/-SD, 56.9+/-7.7 years). BMD of the lumbar spine and femoral neck was measured by dual x-ray absorptiometry. Osteoporosis was defined as a BMD T-score of -2.5 or less at either lumbar spine or femoral neck. Cortical shape and width were evaluated on panoramic radiographs according to our previous study (J Bone Miner Res, 2003). OST index was obtained from integer of 0.2 times weight minus the integer of 0.2 times age. Receiver operating characteristics curve analyses were used to determine the optimal cutoff thresholds for cortical width and OST. Results: The sensitivity and specificity in identifying women with osteoporosis were 90.4% and 39.9% for cortical width, 91.3% and 40.2% for OST, and 80.7% and 65.4% for cortical shape. The likelihood ratio for a positive risk index result in identifying women with osteoporosis was 1.50 (95% confidence interval [CI], 1.34-1.67) for cortical width, 1.58 (95% CI, 1.40-1.77) for OST,and 2.33 (95% CI, 1.94-2.81) for cortical shape. Conclusion: Dentists may be able to refer postmenopausal women with osteoporosis for bone densitometry by panoramic radiographic measures as well as osteoporosis screening tool based on questionnaire.