Altered sensation following extrusion of an endodontic file treated by intentional replantation: case report and treatment recommendations

Objective: An altered sensation during endodontic treatment can occur due to the extrusion of endodontic materials. This study aims to discuss intentional replantation to address paresthesia resulting from an endodontic file penetrating the inferior alveolar nerve canal and provide a protocol for managing nerve injuries in such incidents. 
Case presentation: A 12-year-old girl developed paresthesia when an endodontic file separated and was inadvertently pushed through the apical foramen into the inferior alveolar nerve canal during root canal treatment of the mandibular left first molar. A CBCT scan revealed the file penetrating the canal towards the inferior border of the mandible. After considering the treatment options, intentional replantation was deemed suitable. The tooth was atraumatically extracted and preserved in sterile saline. The surgeon then carefully cleaned and irrigated the socket. The radiographic assessment confirmed successful file removal from the socket. The root ends were resected, and retrograde preparation and obturation were conducted using ultrasonic tips and mineral trioxide aggregate. The tooth was then replanted into the socket. Successful replantation was confirmed by tooth stability and an audible click. The patient was prescribed antibiotics and steroids. After completion of the endodontic treatment, a stainless steel crown was cemented. The successful intentional replantation procedure resulted in rapid improvement in the patient’s condition. The normal sensation had been restored, indicating nerve recovery. At the 15-month follow-up, periapical bone healing and the eruption of the adjacent second molar were observed, affirming the treatment protocol’s overall success.
Conclusion: Prompt intervention and immediate intentional replantation facilitated direct inspection of the separated file within the socket. Collaboration between an oral maxillofacial surgeon and an endodontist ensures expedited and targeted treatment, leading to favorable outcomes.