Objective: to characterize endodontically treated teeth thorough Cone Beam Computed Tomography (CBCT). In addition, to describe the sociodemographic situation of assessed patients, to compare the radiographic and tomographic findings and to evaluate the status of the apical bone related to endodontic treatments performed at Universidad Cooperativa de Colombia. Methods: a transversal descriptive study that included 27 patients who were subjected to an endodontic treatment at Universidad Cooperativa de Colombia between 2015 and 2017. Was performed. Exclusion criteria included pregnant women, uncontrolled systemic diseases and endodontic treatments performed in minors or in deciduous teeth. An informed consent was signed and clinical, radiographic and CBCT examinations were performed. Radiographies and CBCTs were evaluated by a standardized specialist. Results: 31 teeth, mostly posterior, were analyzed. Uniradicular teeth were the most common (38.7%), 48% of the endodontic obturations were located at the radicular apex and the frequency of radiographic lesions was 19.4%. Diagnosis by CBCT allowed to estimate this frequency at 29%, which indicates an underestimation of 9.6% in the diagnosis of lesions when compared with a conventional radiography. The agreement in the diagnosis of lesions assessed by Cohen´s Kappa coefficient between both diagnostic methods was 56.6%. In addition, it was found that the report of a lesion through diagnostic techniques was associated with the report of the obturation level (Vp Chi square=0.025). Statistically significant differences were found in the frequencies of lesions established by the CBCT according to the obturation level. Discussion: the diagnosis of assessed lesions demonstrated that CBCT showed a higher number of apical lesions than the conventional periapical radiography. Regarding the success rate, more apical lesions were found after two years of performing the endodontic procedure in infraobtured teeth. Coronal microfiltration leads to failure of an endodontic treatment. The invasion of microorganisms into the root canal plays an important role in the development of periapical lesions. An inadequate coronal restoration allows for saliva, microorganisms and other products to filtrate, thereby increasing the risk of post-endodontic contamination. Conclusion: it can be concluded that the traditional radiography is not the best diagnostic tool to determine the status of the periapical tissues in teeth subjected to an endodontic treatment. It is mandatory to ensure that the endodontic procedure allows a complete instrumentation of the root canal to avoid infraobturation, which is highly related to the presence of apical lesions. Proper adaptation of the coronal restoration is related to a lower amount of apical lesions observed in a CBCT; therefore, coronal filtration must be avoided.