Case report: endodontic and surgical treatment of an upper central incisor with external root resorption and radicular cyst following a traumatic tooth avulsion.

In the age group between 6 and 12 years, trauma to the upper incisors happens frequently. In the case of avulsion, a replantation is the state-of-the-art treatment; however, it may lead to several complications, particularly if suitable posttraumatic management is not carried out. External cervical resorptions as well as apical granuloma and cysts due to microbial contamination of the root canal are common complications. In the presented trauma case, a conservative approach was chosen to treat a large cystic lesion combined with cervical and apical resorptions. After initial placement of Ledermix and calcium hydroxide into the root canal, a marsupialization with the temporary insertion of an obturator was performed. The gradual reduction led to a fast recovery of the bony defect and a root canal filling was placed. The 2-year follow-up showed an improved condition. All adjacent teeth remained vital during the course of the treatment.