[The radiological-histological interpretation of artificial bone defects of the basal maxillary sinus cortical bone]

Twenty-one lateral maxilla specimens were taken from human autopsy specimens and after removing soft tissue 40 differing tooth roots of 23 molars and premolars were ground to create large artificial bone defects in the supporting cortical bone of the basal maxillary sinus. Conventional dental radiographs and axial CT scans were then compared with the macroscopic findings in relation to the identification of the artificial bone defects. Next the jaw segments were dissected analogous to the axial CT scan and corresponding histological microsections were prepared for a radiological-histological comparison. None of the artificial bone defects were identifiable on the dental radiographs. In comparison to this, however, cortical bone defects were identifiable on 25 tooth roots (62.5%) on the CT scans. The lateral demarcation of the antral defects on the CT scans depends on the setting of the tooth root, on the adjacent bone morphology, and on the visualization of the periodontal ligament space. If the periodontal space shows up on the CT images, it becomes possible to demarcate of a thin, 0.2 to 0.5 mm, cortical bone layer of the basal maxillary sinus.