INTERRELATIONSHIPS BETWEEN BONE-MINERAL CONTENT MEASURES - DUAL-ENERGY RADIOGRAPHY (DER) AND BITEWING RADIOGRAPHS (BWX)

In vitro periodontal alveolar bone mineral content (BMC) measurements obtained with dual-energy radiography (DER) were compared with assessm ents based on bitewing radiographs (BWX). In addition, in patients, th e relationship between bitewing and several postcranial dual-energy-ra diographic measures were evaluated. Dual-energy-radiographic and bitew ing measurements were made on 2 cadaver mandibles initially and after 2 incremental bone reductions at 4 sites. Rank-order correlations betw een dual-energy-radiographic and bite-wing measures for the 4 sites ra nged from 0.7 to 1.00. Bitewing measures indicated true bone loss with a sensitivity of 1.00. For patients, correlations between bitewing me asures and dual-energy-radiographic scans suggested the strongest rela tionships were in the distal sections of the radius and ulna and in th e intertrochanteric and Ward's areas of the femur. Correlations, in th e 0.5-0.6 range, were not statistically significant (p > 0.05), but we re quite robust considering the small sample size and preliminary natu re of this investigation. Results suggest that the bitewing measure is sufficiently sensitive to detect clinically meaningful (5% or greater ) changes in alveolar BMC and, further, that alveolar bone mineral con tent may reflect postcranial BMC. The implications of postcranial bone mineral changes being reflected in alveolar bone would enhance both o ur understanding and treatment of alveolar bone loss. The use of bitew ing measures to facilitate identification of patients with postcranial bone loss is discussed.