Number of basis images effect on detection of root fractures in endodontically treated teeth using a cone beam computed tomography machine: an in vitro study

Objectives: The objective of this study was to compare the accuracy of root fracture detection in endodontically treated teeth using scans acquired with a 180° rotation motion compared with a 360° after which the patient exposure and number of basis images are doubled. Methods: Sixty-six roots were collected and decoronated. All were treated endodontically. One-half of the roots were fractured, resulting in 2 root fragments which were then glued together. The roots were placed randomly in 8 prepared beef rib fragments. Five reviewers independently reviewed the scans twice, at different times. Results: The specificity of the 360° scan was significantly higher than the 180° scan; doubling the basis images leads to a significant decrease in false-positive rates. Accuracy and sensitivity were not significantly different. Conclusions: Only the specificity is improved by the increased rotation and doubling of images. The accuracy and sensitivity are not improved.