Clinical and histopathological characterization of root resorption in replanted teeth: Two case reports

RATIONALE: The frequency of tooth avulsion is on the rise due to increasing rates of maxillofacial trauma. Avulsed teeth present with varying degrees of root resorption, and are generally asymptomatic; therefore, they often go undiagnosed. The etiopathogenesis of root resorption in replanted teeth following avulsion remains unclear. PATIENT CONCERNS: In case 1, the left upper lateral incisor became loose after 10 years of replantation. In case 2, the patient underwent tooth replantation after external root canal treatment due to tooth dislocation caused by trauma 8 years ago. DIAGNOSIS: According to the medical history, clinical manifestations and imaging studies of the 2 patients, root resorption after replantation was diagnosed. INTERVENTIONS: The teeth extraction was given to one patient. Besides the histological examination of extracted teeth was performed. OUTCOMES: Teeth that underwent pulp treatment presented with external resorption. On the other hand, the tooth that had received no pulp treatment showed both external and internal resorption; residual vital pulp tissue was detected within the pulp cavity. LESSONS: The dental pulp tissues may be involved in the initiation or development of internal resorption. Trauma to the periodontal ligament might play a major role in external resorption, whereas internal tooth resorption may be caused as a result of injury to the residual pulp tissue. Thus, the effective management of these tissues during the treatment of replanted teeth is essential.