Accuracy of Proximal Caries Depth Measurements: Comparison of Two Computed Cone Beam Tomography and Storage Phosphor Plate Systems

WOS: 000410750200006Objective: The aim of this study was to compare the accuracy of NewTom 9000 [cone beam computerized tomography (CBCT)], Accu-I-Tomo [limited CBTC (LCBCT)] and Digora Optime [storage phosphor plate (SPP)] imaging systems in assessing the depths of defects with different shapes and sizes on the proximal surfaces of teeth. Materials and Methods: Thirty out of 50 incisive teeth with sound proximal surfaces were divided into three equal groups. Mechanical defects of different sizes and depths were created on their proximal surfaces and teeth were placed in acrylic blocks with approximal contacts. Radiographs of the blocks were obtained with CBCT, LCBCT and SPP systems. The depth measurements of 60 artificial defects were performed by 3 radiologists in the digital radiographs. The gold standard (true measure) was defined as the mean of the 2 observers' measurements on the microscopic sections. Results from imaging systems and true depths were compared using Bland-Altman plots. The agreement was determined with intra-class correlation coefficient. Results: Maximum deviation from the true length in axial and sagittal slices of CBCT system was 2 mm [95% confidence interval (CI) 2.60-0.60] and 1.5 mm (95% CI 0.30-2.30) respectively while the deviation of LCBCT was 0.66 mm (95% CI 0.53-2.22) and 0.37 mm (95% CI 0.50-2.25). The deviation from truth for SPP was 0.66 mm (95% CI 0.33-2.25). Correlation among observers was 0.487 and 0.700 respectively, for CBCT axial and sagittal slices; while it was 0.979 and 0.985 for LCBCT and 0.979 for SPP. Conclusion: Images obtained with the Accu-I-Tomo LCBCT system were more accurate than Newtom CBCT and Digora SPP system for measurement of caries lesion depth. Correlation among observers was higher for LCBCT and SPP systems compared with CBCT system