Case of mistaken identity: periapical cemental dysplasia in an endodontically treated tooth.

A case of a patient with a history of root canal treatment and re-treatment and a persistent periapical radiolucency is reviewed. Following surgery, biopsy material was submitted and diagnosed as periapical cemental dysplasia (PCD). With careful diagnosis, PCD should be readily differentiated from endodontic pathosis, thus avoiding unnecessary root canal treatment. In this case, surgery was necessary to rule out other inflammatory disease or benign odontogenic entities.