Visually assessing radiographs of the jaw is an accurate and reliable way to identify women at risk of developing osteoporosis, study findings show.
Bone mineral density (BMD) in the jaw decreases with age, and this process is thought to reflect BMD loss in other parts of the skeleton, such as the hip.
Indeed, MedWire News recently reported results from a small study showing that erosion in the mandibular inferior cortex was significantly correlated with general bone loss indicated by levels of bone turnover markers such as bone-specific alkaline phosphatase.
The loss of BMD in the jaw is characterized by change in the trabecular structure of the bone - a feature that can be easily seen on radiographs.
Since millions of radiographs of the jaw are taken each year by dentists, Christina Lindh (Malmö University, Sweden) and fellow members of the OSTEODENT Study team reasoned that this might constitute an effective osteoporosis screening opportunity.
To determine how accurately visual assessment of jaw radiographs predict BMD loss, three experienced oral radiologists and two general practitioners with an interest in oral radiology examined intra-oral peri-apical radiographs of the maxillary and mandibular pre-molar region of 600 women aged between 45 and 70 years.
The women were deemed to have a high risk of osteoporosis and were recruited at routine and emergency dental visits, and through advertising.
The five observers classified the trabecular pattern on the radiographs as dense, heterogenous, or sparse, compared with reference images, and predicted the presence or absence of osteoporosis based on their conclusions.
The predictions identified osteoporosis, as later confirmed by dual energy X-ray absorptiometry, with a specificity of 91.6% for the upper jaw and 90.8% for the lower jaw.
Level of agreement between the observers was also high, giving weighted kappa values of 0.53 and 0.57 for the upper and lower jaw, respectively.
The sensitivity of visual radiograph assessment to detect osteoporosis was, in contrast, low, with values of 28.2% for both the upper and lower jaw.
Based on their results, the researchers conclude in the journal Oral Surgery, Oral Medicine, Oral Pathology, Oral Radiology, and Endodontology: "Visual assessment of the trabecular pattern in intra-oral peri-apical radiographs of pre-molar regions is a potential method to identify women at risk of having osteoporosis."