The purpose of this study was to compare different high-resolution cone-beam computed tomographic (CBCT) imaging protocols in the diagnosis of incomplete root fractures of endodontically treated teeth.Twenty single-rooted human teeth were endodontically treated, and an incomplete root fracture was induced. The teeth were scanned with the CBCT unit PreXion 3D (Teracom, San Mateo, CA) operating at 2 different protocols: high resolution/standard (HI-STD) (19 seconds and 512 basis images) and high resolution/high density (HI-HI) (37 seconds and 1024 basis images). Three oral radiologists evaluated all images using multiplanar reconstructions. The diagnostic tests and the receiver operating characteristic (ROC) curve were calculated.The HI-STD and HI-HI protocols presented an accuracy of 0.90 and 0.93, respectively, and both protocols had a sensitivity of 0.97. The HI-HI protocol showed a higher positive predictive value and slightly higher areas under the ROC curve.Both high-resolution imaging protocols presented high accuracy in the detection of incomplete root fracture of endodontically teeth. Thus, the HI-STD protocol should be indicated this reduces the radiation dose.