[The effect of mandibular bone density assessed by orthopantomography on the bone resorption of the alveolar crests]

The present study aimed to determine the value of orthopantomography in evaluating mandibular bone density in edentulous subjects; the authors proposed to correlate bone density evaluated using this methods with residual ridge resorption, age, and time of edentulism in the subjects in question. Bone density was evaluated from panoramic X-rays in 70 completely edentulous subjects through the observation of characteristics of bone trabeculae in a constant site for all 70 OPT, in correspondence with the horizontal blade of the jawbone, and through the subdivision of panoramic X-rays into three classes according to the greater or lesser compactness of the trabeculae of the cancellous bone. The resorption of residual ridges was assessed from OPT using Wical and Swoope's method. Correlations between bone density and residual ridge resorption, expressed in both mm and %, was statistical not significant. Correlations between the age of subjects examined and bone density, and between time of edentulism and bone density were also statistically not significant. The results obtained however appear to have been influenced by the non-reliability of data provided by OPT and draw attention to the need, in fully edentulous subjects, when programming, for example, osseointegrated implants, to study the quality of mandibular bone using more accurate and precise methods.