Purpose: To present the diagnostic challenge of a clinical case of vertical root fracture (VRF) in an endodontically treated mandibular left lateral incisor.
Case Description: At 16 months after endodontic treatment, a 60-year-old female patient reported pain during mastication. Clinically, she presented with an active distolingual fistula and a probing depth of 9 mm on the distal aspect of tooth 32. A radiographic examination indicated pear-shaped distal bone loss. The fistula was mapped, which confirmed that the lesion had a periodontal origin. A diagnostic hypothesis of a VRF was established. Exploratory surgery revealed the VRF on the distolingual aspect of the root without separation of the root fragments.
Conclusion: Knowledge of the diagnostic aspects and the correct interpretation of radiographic images was enough to establish the diagnostic hypothesis of a VRF. However, the conclusive diagnosis was only confirmed during exploratory surgery.