Introduction:Due to the risk of exposure to ionizing radiation, principles of radiation protection have been established, with the aimto regulate activities that involve the use of ionizing radiation. The principle of justification means that the indication of the exam must be associated to the possibility of providing information for the benefit of the patient. The indication of an exam that results in a benefit for the patient entails the evaluation of the exam in terms of its perfor-mance. This evaluation should demonstrate the exam has ability to deliver the necessary information for the specific need of the patient. Review:The Diagnostic Efficacy model, described by Fryback and Thornbury in 1991, is used to evaluate the performance of imaging tests, in order to guide its use as a diagnostic tool in different dental indications.In dentistry, the use of TCHC has increased due to the advantages as a diagnostic tool. Still, there are few investigations at high levels of the Diagnostic Efficacy model – related to characteristics that involve the patient-and many investigations at low levels – more related to technical quality and diagnostic accuracy. Conclusions:Evidence of the performance of CBCT at low levels generates a misunderstanding about its use, giving the impression that CBCT has sufficient scientific support to justify its use. Currently, the evaluation of the performance of the TCHC has focused on evaluating the lowest levels of this model, the image quality and the diagnostic precision, although evidence at this level remains limited. Research focusing on the benefit of patients with the use of CBCT for the different indications in dentistry is needed.