The Biomineralization Conundrum of Calcified Extraradicular Deposits on the Apical Root Surface of Teeth: A Case Report

Background: Calcified extraradicular deposits on the apical root surface of teeth (CEDARST) are rarely seen in the dental field, compared with dental calculus deposits, which are very frequent. However, the exact biomineralization process of this entity has remained unclear until now. Objective: To report a case of an exuberant calcified extraradicular deposit on the apical root surface of an anterior tooth with apical periodontitis and propose for the first time some potential mechanisms involved in this pathological mineralization, and thereby suggest directions for future research. Case Presentation: In brief, a root-canal-treated canine displaying a radiographic periapical radiolucency was treated, and the sinus tract persisted despite root canal retreatment in which high endodontic standards were maintained. Endodontic surgery was performed, and the curettage of the pathologic tissue revealed an exuberant calculus-like material attached to the outer root surface, around the exit of the apical foramen. Two-year follow-up radiography revealed complete bone healing, and the patient´s tooth was asymptomatic and functional. Conclusion: The development of CEDARST seems to depend on a fine synergic control exerted by specific microorganisms (mainly bacteria) on this pathological mineralization, as well as on the local chemical microenvironment of the apical lesion of the affected tooth. Microbial implications and inhibitors of mineralization seem to play a dominant role in CEDARST biomineralization.