The aim of this study was to report the management of root resorption after a traumatic dental injury in an 11-year-old female patient by changing endodontic treatment. An 11-year-old healthy female patient was referred to Paediatric Dentistry Clinic with a history of avulsion to the maxillary right central incisors due to an accidental fall that occurred 12 months before her referral. Radiographic examination showed external and internal root resorption of the root of the maxillary right central incisor. The tooth was slightly movable, and the patient had pain while the tooth was in normal function. Previous endodontic therapy was performed last year with Calasept Calcium Hydroxide. Biodentine (Septodont) endodontic placement in the affected root was performed in the clinic to try to stop the resorption. Over a period of 12 months the treated tooth was followed clinically and radiographically every 2 months to supervise the state of the root. There were no complications, and the resorption was stopped. The tissue started to heal due to the osteogenic properties of the material and the root resorption was reversed in this case. The method used in this clinical case was the use of Biodentine which proved to be successful. It increased the osteogenic potential of the root and promoted the formation of dentin bridges. There were no complications after the treatment during the 12-month follow-up.