Assessment of Human Alveolar Bone Density by Using Volumetric CT Machine

This study evaluated bone density in designated implants sites using cone-beam computed tomography (CBCT) and compared the measurements to those of quantitative computed tomography (QCT) and subjective bone density evaluation. Sixty-two designated implant sites in 9 human cadavers jaws were used. Indicator rods, 2 mm in diameter, were placed in all sites. CT images representing 1 mm bucco-lingual slices immediately mesial and distal to the rods were selected for density evaluations. Bone density in Hounsfield units (HU) was assessed in a standardized implant area superimposed on the images, and also subjectively evaluated by 2 independent examiners using the Lekholm & Zarb (1985) classification. Density measurements in HU in most of the areas, except for mesial middle third, of CBCT were comparable to those of QCT with Intraclass Correlation Coefficient values more than 0.8. When CBCT measurements were related statistically to CBCT subjective reading, there was a moderate association interpreted by Spearmans rho value 0.5. However, there was a low agreement of intramachine and inter-machine subjective readings with Kappa statistics value 0.32 and 0.36, respectively. Reproducibility of subjective scoring by Lekholm and Zarb Classification of images from CBCT is not statistically different (P \u3e 0.05) from that of images from QCT. This cone-beam CT machine could be considered as a new modality of diagnostic tool in dental treatment, especially when bone density values are important