Evaluation of bone mineral density in postmenopausal women with alterations of the mandible cortical bone.

OBJECTIVE: Menopause affects the bone quality and quantity of jaw bone. The aim of this study was to evaluate the validity of mandibular cortical measurements in the diagnosis of low bone mineral density (BMD) in postmenopausal women.

METHODS: A total of 113 postmenopausal women (mean age 63.15±6.05 years), living in Lithuania, were examined. Participants were categorized as either normal BMD, or low BMD according to the WHO classification in relation to their spine BMD determined by dual energy x-ray absorptiometry. None of the participants were known to have endocrine, metabolic or skeletal disorders. BMD was measured in the spine lumbar area L2-L4. The mandibles were examined on panoramic x-ray images. The following radiomorphometric indices were measured: the height of the mandibular inferior cortex below foramen mentalae (IC) and cortical thickness at the angle of the mandible (Panoramic Angular Index (PA)). Receiver operating characteristics (ROC) curve analysis was used to determine the validity of cortical measurements in the diagnosis of low BMD obtained and the area under the ROC curve (AUC) was calculated.

RESULTS: Significant associations were found between IC and PA, and low BMD. The areas under the ROC (AUC) of PA was 0.753 (95% CI, 0.645-0.861) and of IC was 0.709 (95% CI, 0.601-0.816). High levels of intra- and interobserver agreement were demonstrated.

CONCLUSIONS: Postmenopausal women with spinal low BMD can be identified moderately accurately by mandibular cortical findings.