Iranian Endodontic Journal

Abstract

This case report describes the successful guided endodontic treatment of a maxillary left canine (#23) with pulp canal obliteration (PCO) in a 30-year-old female patient. The patient had a history of orthodontic treatment and Le Fort I orthognathic surgery, both recognized as potential factors contributing to canal calcification. The patient had a history of a failed root canal treatment, contributing to incomplete canal instrumentation and iatrogenic damage (gouging) during access cavity preparation. The case was referred for completion of treatment. Upon referral, clinical and radiographic examinations revealed advanced canal obliteration, procedural gouging from the prior attempt, and a radiolucent line suggestive of a horizontal root fracture. Cone-beam computed tomography (CBCT) confirmed the extent of canal calcification, ruled out the suspected fracture, and showed a localized palatal external root resorption, likely related to previous orthodontic forces. Given the complexity of the case, a static-guided endodontic technique was selected as the preferred treatment approach. A custom 3D-printed guide, generated from merged CBCT and intraoral scan data, enabled conservative and accurate access to the calcified canal. Although a hand K-file fractured during canal negotiation, the fragment was successfully retrieved using ultrasonic devices under magnification. The tooth was treated successfully. Clinical and radiographic follow-ups at six and twelve months confirmed resolution of the periapical lesion and complete symptom relief, demonstrating that guided endodontics can serve as a safe and effective treatment option in teeth with PCO.