ROOT RESORPTION AND APICAL BREAKDOWN DURING ORTHODONTIC TREATMENT OF A MAXILLARY LATERAL INCISOR WITH DENS-INVAGINATUS

A 13-year-old girl was referred for endodontic treatment of a maxillar y right lateral incisor with root resorption and apical radiolucency a fter orthodontic treatment. Radiographically the tooth had an invagina tion canal (Oehlers' Type III) and responded positively to pulp testin g. The invagination canal extending to the lateral resorption was open ed. Vital bleeding tissue was found, and the canal was cleaned and obt urated. The pulp in the main root canal remained vital. The radiolucen t lesion gradually decreased during the 3-year follow-up. The bone res orption seen here, despite vital tissue in the invagination canal, was probably due to osteoclastic activity caused by a low grade chronic i nfection, influenced by an injury-induced inflammation in the periodon tium during orthodontic treatment.