Prediction of age-related osteoporosis using fractal analysis on panoramic radiographs

PURPOSE: This study was performed to evaluate the trabecular pattern on panoramic radiographs to predict age-related osteoporosis in postmenopausal women. MATERIALS AND METHODS: Thirty-one postmenopausal osteoporotic women and 25 postmenopausal healthy women between the ages of 50 and 88 were enrolled in this study. The bone mineral density (BMD) of the lumbar vertebrae and femur were calculated using dual-energy X-ray absorptiometry (DXA), and panoramic radiographs were obtained. Fractal dimension (FD) was measured using the box counting method from 560 regions of interest (51x51 pixels) in 6 sites on the panoramic radiographs. The relationships between age and BMD and between FD and BMD were assessed, and the intraobserver agreement was determined. RESULTS: There was a significant difference in the FD values between the osteoporotic and normal groups (p<0.05). There was a significant difference in the FD values at three sites in the jaws (p<0.05). Age was significantly correlated with the BMD measurements, with an odds ratio of 1.25. However, the FD values were not significantly correlated with the BMD measurements, with an odds ratio of 0.000. The intraobserver agreement showed relatively higher correlation coefficients at the upper premolar, lower premolar, and lower anterior regions than the other sites. CONCLUSION: Age was an important risk factor for predicting the presence of osteoporosis in postmenopausal women. The lower premolar region was the most appropriate site for evaluating the FD value on panoramic radiographs. However, further investigation might be needed to predict osteoporosis using an FD value on panoramic radiographs.

Measurement of hone mineral density in the proximal humeral region / 中华创伤骨科杂志

Objective To establish a method of measuring bone mineral density (BMD) in the proximal humeral region, and explore the relationship between proximal humeral BMD level and age and body mass index (BMI).Methods A scanning procedure was developed, using a shoulder & forearm position device.Firstly, 30 subjects were examined on the proximal humerus with 2 successive scan sessions to de-termine the short-term precision.Secondly, scanning of the right proximal humerus BMD in 92 healthy women was done.Results Short term precision revealed that RMS SD was 0.011 g/cm2, and RMS CV (coefficient of variation) on BMD measurement was 2.4%.Proximal humeral BMD values decreased with age.No correlation existed between the proximal humeral BMD and BMI.Conclusions The method of measuring BMD over the proximal humeral region is reasonable, and the short term precision of the result is acceptable.Proximal humeral BMD tends to decrease with age.Since the shoulder is subject to the least in-fluence of weight and stress loading, the proximal humeral BMD scan might be an early stage indicator of osteoporosis.