Abstract
Volumetric Tomography (VT) is a new three-dimensional dental imaging technique, and the dose to the patient is relatively low. The purpose of this study was to compare the difference in the performance of proximal caries diagnosis using VT and intraoral radiography in primary teeth.101 proximal surfaces of 58 extracted human primary molars were used. Eleven base images were obtained by the VT imaging method to reconstruct VT slices. Intraoral radiographs were acquired using Kodak Insight film. Eight observers scored the presence or absence of proximal caries in the teeth using two imaging modalities. The true presence of caries and its depth were determined using the sectional images obtained in the ground truth using micro CT. Areas under the receiver operating characteristic (ROC) curves (Az) for each combination of observer and image modality were calculated and assessed using the paired t-test. Among the caries depth and modalities, observers' assessments were compared with the ground truth using the chi-square test.The mean ROC curve (Az) values were 0.828±0.026 for VT slices and 0.853±0.041 for intraoral radiographs for the detection of proximal caries in primary molars. The paired t-test showed no statistically significant differences between modalities. The chi-square test showed a statistically significant difference (p＜0.05) for VT slices in upper second primary molars with caries in internal 1/2 of dentin. On the other hand, the chi-square test showed a statistically significant difference (p＜0.05) in lower first primary molars, and a statistically significant difference (p＜0.01) on all surfaces for intraoral radiographs with no caries.Within the limited range of this study, VT slices provide a comparable diagnostic performance in detecting caries and in estimating its depth. Many studies will be needed to enhance the diagnostic accuracy by improving the mechanical procedures. And VT may be a feasible method for diagnosing caries depth.
