Canine Type III Invagination With Apical Periodontitis: A Case Report

Tooth invagination is a developmental anomaly caused by the inward folding of the enamel organ into the dental papilla during tooth formation. Due to the intricate root canal morphology, traditional endodontic treatment may be insufficient with potential persistent infection. An 11-year-old child presented with discomfort in the right upper anterior teeth for several days. Clinical examination revealed a hypoplastic crown of tooth 13 with percussion pain. CBCT showed that coronal hard tissue invaginations in tooth 13 exceeding beyond the cemento-enamel junction and reaching the apex. The apical foramen was flared, and a large area with unclear boundary of low-density imaging around the apex was observed. In this case, bioceramics iRoot BP Plus was placed as an apical barrier. Initial management involved canal disinfection with root canal preparation, ultrasonic irrigation, and calcium hydroxide as intracanal medication. The canal was subsequently obturated with thermoplasticized gutta-percha and restored with composite resin. Six months post-treatment, the patient was asymptomatic, and radiography showed significantly reduction in the periapical radiolucency. This case is classified as Oehlers type III invagination, the most severe form. CBCT is essential for confirming the complex root canal morphology. Given the open apical foramen of the young permanent tooth, iRoot BP Plus provided an effective apical sealing. For endodontic diseases in invagination teeth, individualized treatment plans should be made according to the anatomical structure of the complex root canal, pulp and periapical infection status, and the degree of root development.