Head Angulation in Cone-beam Computed Tomography Acquisition: Effect on the Diagnostic Accuracy of Vertical Root...

Vertical root fractures (VRFs) detection in cone-beam computed tomography (CBCT) images can be challenging when gutta-percha artifacts are present. This study aimed to evaluate how anteroposterior and laterolateral head angulations (APHA and LLHA, respectively), as well as tooth position (anterior or posterior region), influence the diagnostic accuracy of VRFs detection in CBCT for endodontically treated teeth.

Twenty single-rooted teeth were endodontically treated. A phantom was created using a human mandible and ballistic gelatin. CBCT scans of each tooth, placed in both the anterior and posterior regions, were acquired with the phantom positioned at the standard position of 0°, at APHA of 30° and 45°, and at a LLHA of 20°, totaling 320 scans. The presence or absence of VRFs was assessed by 6 examiners using a 5-point scale. Area under the receiver operating characteristic curve, sensitivity, and specificity were analyzed using two-way repeated measures analysis of variance and Sidak's post hoc test. Intra- and interexaminer agreement was evaluated using the weighted Kappa coefficient (α = 0.05).

In general, the 30° and 45° APHA significantly increased area under the receiver operating characteristic curve and sensitivity values for VRF detection in both anterior and posterior regions compared to 0° and 20° LLHA. Angulations and tooth position did not influence specificity. For specificity values, the 45° APHA exhibited a significantly higher value than the other angulations in the anterior region.

VRFs diagnosis enhanced at 30° and 45° APHA, regardless the region.