[3-dimensional computed tomographic imaging of the dentate alveolar ridge. A radiological-histological comparison]

Human bone segments of the toothed jaw with ten upper and ten lower teeth were scanned by high resolution computer tomography in continuous parallel axial and coronal slices (Somaton plus, Siemens). In both directions scanning was performed to 1 mm and 2 mm thicknesses and at 1 mm and 2 mm intervals. The jaw segments were dissected analogously in 1 mm thick slices. Contact films of the corresponding bone segments were exposed and then histological thin sections prepared. The statistical comparison between the CT exposures, the contact films, and the histological sections revealed an average absolute deviation of 0.3 to 0.5 mm with the axial CT exposures and a deviation of 0.3 to 1.6 mm with the coronal sections. It was possible to interpret in a quantitatively detailed manner the teeth and surrounding bone compacta up to a 0.5 mm minimum bone thickness. Computer-enhanced secondary reconstructions made possible an additional qualitative interpretation of the bone upper surface and the freely definable planes. Continuous parallel axial CT slices enable an interference-free, proportionally accurate representation of the apical base, the periodontal bone structure, and the radice-root topography.