Computer-aided measurement of mandibular cortical width on dental panoramic radiographs for identifying osteoporosis.

To develop a computer-aided diagnosis system to continuously measure mandibular inferior cortical width on dental panoramic radiographs and evaluate the system's efficacy in identifying postmenopausal women with low-skeletal bone mineral density. Mandibular inferior cortical width was continuously measured by enhancing the original X-ray image, determining cortical boundaries, and evaluating all distances between the upper and lower boundaries in the region of interest. The system's efficacy in identifying osteoporosis at the lumbar spine and the femoral neck was evaluated for 100 women (≥50 years): 50 in the development of the tool and 50 in its validation. The sensitivity and specificity of the cortical measurements for identifying the development patients were 90% (95% confidence interval shown in parentheses) (63.0-87.0) in women with low spinal bone mineral density, and 81.8% (70.1-91.8) and 69.2% (56.2-81.8) in those with low femoral bone mineral density, respectively. Corresponding values in the validation patients were 93.3% (85.9-100) and 82.9% (71.4-92.7) at the lumbar spine, and 92.3% (84.5-99.5) and 75.7% (63.0-87.0) at the femoral neck, respectively. Our new computer-aided diagnosis system is a useful procedure in triage screening for osteoporosis.