case_images: PMC10565997_01
case_images: Treatment of case 1, A) Preoperative periapical radiograph; B, C) Preoperative clinical aspects of teeth #26 and #27; D) Ultrasonic tip cleaning the pulp chamber; E,
  F) the four root canals located; G, H, I) The four root canals cleaned; J, K) Immediate postoperative periapical radiographs; Abbreviations of root canals: mv, mesio-buccal 1; mv2, mesio-buccal 2; db, distobuccal; and P, palatal
case_images: IEJ-18-264-g001.jpg
case_images: PMC10565997_01_IEJ-18-264-g001.jpg
case_images: F1
case_images: The patient's gingival tissue was normal, with no bleeding or exudation from the gingival sulcus and no sinus tracts were present (Figure 1B, 1C). The periapical radiograph revealed an unsatisfactory endodontic treatment due to wrong apical limit of working length and filling failures (Figure 1A). On the first visit the filling materials were removed from the root canal with a Reciproc R25 file (VDW, Munich, Germany) and Clearsonic, Flatsonic, and Irrisonic ultrasonic tips (Helse Dental Technology, Santa Rosa de Viterbo, Brazil) (Figure 1D). After the radiographic verification of the filling's quality, the tooth was restored with composite resin (Figures 1J, K) and the patient was instructed to undergo an evaluation with a periodontist. The sequence of the treatment can be seen in Figure 1.
case_images: Comparative CBCT images of case 1 (preoperative and after 8 months), A, B,C) Axial sections at cervical, middle and apical thirds, respectively; D, E) Sagittal images; F, G) Coronal images; The red arrows indicate the osteolytic lesion (preoperative) and the blue arrows the bone recovery (postoperative, 8 months after)
case_images: IEJ-18-264-g003.jpg
case_images: PMC10565997_01_IEJ-18-264-g003.jpg
case_images: F3
case_images: The analysis of the axial, sagittal and coronal planes revealed extensive bone loss in the distobuccal root and distal interproximal region extending to the furcation area. Furthermore, a big periapical lesion was observed in the apical region of palatal roots of both #26, #27 teeth. The communication between the periapical lesion and bone loss area in the distal region resulted in an EPL diagnosis (Figures 3A, 3B, 3C, 3G).
case_images: PMC10565997_02
case_images: Treatment of case 2, A) Preoperative clinical aspect (sinus tract); B) Access Cavity; C) Absence of the sinus tract 14 days after the first session; D) Preoperative periapical radiograph; E) Immediate postoperative periapical radiograph
case_images: IEJ-18-264-g002.jpg
case_images: PMC10565997_02_IEJ-18-264-g002.jpg
case_images: F2
case_images: The patient's gingival tissue was normal with no bleeding or exudation from the gingival sulcus, and a sinus tract was present (Figure 2A). The periapical radiograph revealed the presence of a periapical lesion in the mesial root as well as in the furcation area (Figure 2D). In the second session, the absence of the sinus tract was confirmed (Figure 2C). After the radiographic verification of the filling's quality, the tooth was restored with composite resin (Figure 2E) and the patient was instructed to undergo an evaluation with a periodontist. The sequence of the treatment can be seen in Figure 2.
case_images: Comparative CBCT images of case 2 (preoperative and after 5 months); A, B) Sagittal images; C, D, E, F) Coronal images; G, H) Axial images at cervical and apical thirds respectively; The red arrows indicate the osteolytic lesion (preoperative) and the blue arrows the bone recovery (postoperative 5 months after)
case_images: IEJ-18-264-g004.jpg
case_images: PMC10565997_02_IEJ-18-264-g004.jpg
case_images: F4
case_images: Furthermore, an extensive bone loss was observed at the lingual cortical plate and the communication between the apical lesion, the furcation area and the cortical lingual plate resulted in an EPL diagnosis (Figures 4C, 4E).