Background: The differential diagnosis of endodontic and periodontal diseases can sometimes be clinically difficult, but it is vital to establish a correct diagnosis so that predictable treatment can be offered. Aim: The aim of this study was to highlight the prevalence of endo-periodontal lesions in the frontal dental group of the lower jaw depending on the degree of bone resorption as well as endodontic filling resorption in different patients, some of them with orthodontic treatment, using conical beam computed tomography (CBCT). Materials and methods: A number of 31 CBCT imaging volumes and the medical records of these patients were selected for analysis by an experienced examiner. The sites selected for analysis were divided into two subgroups, one where the endodontic treatment was performed with Endomethasone™ (Colthene, Creteil, France) (7 patients), and the other where it was performed with Adseal™ (Meta Biomed, Seoul, South Korea) (6 patients). Results: The mean age of the study population was 24.1 years, and 35.8% presented previous orthodontic treatment in their medical history. There were no statistically significant differences (p = 0.54) between groups regarding the length of the endodontic filling, the Endomethasone group showing a total length of 11.24 millimeters while the Adseal group showed a total length of 10.85 millimeters. Conclusions: The image obtained in clinical situations in which patients present combined endodontic-periodontal lesions is of real help because in many cases, with the help of CBCT, the starting point of a combined lesion can be highlighted, whether it is endodontic or periodontal.
