Long-term Complications of Previously Successful Regenerative Endodontic Procedures after Orthodontic Movement: A Report of 3 Different Complications after 4, 8, and 11 Years.

There is a paucity of literature on late complications of regenerative endodontic procedures. The aim of this article was to report 3 cases of previously successful regenerative endodontic procedures with long-term follow-up that developed different complications after the application of orthodontic forces. In the first case, an 8-year-old female patient received a regenerative endodontic procedure in her previously intruded tooth (tooth no. 21) that had been rendered necrotic after a successful spontaneous repositioning procedure. The 5-year follow-up revealed uneventful healing, continuous root development, dentinal wall thickening, and regaining of pulp vitality for tooth no. 21. Four years later, the patient received orthodontic treatment with mild forces that lasted 2 years. The 11-year follow-up revealed severe external invasive cervical resorption, and the tooth had to be extracted. In the second case, a 6-year-old female patient suffered a lateral luxation injury in tooth no. 11. Six months after the injury, the tooth developed symptoms and discoloration and tested negative in pulp vitality testing. Single-step regenerative endodontic procedures were applied, and successful continuous root development, dentinal wall thickening, and apical closure were achieved at the 3-year follow-up. Two months after the initiation of orthodontic treatment, the tooth developed symptomatic apical periodontitis. Root canal treatment was performed to treat the disease, and the orthodontic treatment was continued. In the third case, a previously published successful regenerative endodontic procedure developed a perforating internal resorption 6 months after the application of orthodontic forces. The internal resorption was arrested with root canal treatment, the resorptive defect was repaired with bioceramic obturation, and the orthodontic treatment plan was modified. Previously successful regenerative cases might develop external invasive cervical resorption, regenerative tissue necrosis, or internal resorption after the application of orthodontic forces. Best practice/evidence-based guidelines on the appropriate orthodontic management of successful regenerative endodontic therapy teeth are lacking. Whenever possible, careful monitoring and partial or complete exclusion off orthodontic treatment might be necessary. In some cases, preventive root canal treatment before the initiation of orthodontic movement might be considered.