Abstract
We evaluated the utility of three-dimensional computed tomography (3 DCT) for the examination and diagnosis of periodontal disease. Bone resorption or root morphologies affecting the prognosis of periodontal treatment were diagnosed using 3 DCT and conventional intra-oral radiography. The presence of vertical bone defects, bone resorption around the palatal root, furcation involvement, fenestration, enamel projection and root grooves was examined in eight periodontal patients, and the appearances of these factors were verified during flap operations. One-hundred and sixty randomly selected dental radiographies and 160 3 DCT images were presented to twenty dentists. The dentists were divided into three groups according to their experience with periodontal treatment. The presence or absence of the above factors was judged using a 5-rank system. The accuracy of the diagnosis was then evaluated using receiver operation characteristic (ROC) analysis. The results of the 3 DCT examinations were equal or more accurate at identifying all of the examined factors than conventional radiography. Only the vertical bone defect was accurately diagnosed by conventional radiography; fenestration and enamel projection were not diagnosed using the conventional method. Furthermore, the accuracy of the diagnosis for bone resorption around the palatal root of the first molar and furcation involvement depended on the experience of the dentist. Diagnoses based on the 3 DCT images were accurate for all factors except root groove, regardless of dentist experience. The tendency for false positive diagnoses based on conventional radiography increased withperiodontal treatment experience. On the other hand, diagnoses were more accurate when based on 3 DCT images, regardless of dentist experience. These results indicate that 3 DCT greatly facilitates the diagnosis of periodontal disease, regardless of dentist experience, and suggest that 3 DCT images provide useful information for determining appropriate periodontal treatment plans and procedures. J Jpn Soc Periodontol, 45 : 56-66, 2003.
