Background and purpose: Internal inflammatory root resorption (IIRR) is an uncommon lesion in permanent tooth that could lead to destruction of root and the surrounding dental hard tissues if it is left untreated. This article describes treatment of an extensive perforating internal root resorption in a maxillary second premolar using mineral trioxide aggregate (MTA).

Case report: After chemomechanical cleaning of the root canal and the resorption lacuna, calcium hydroxide was placed as an intracanal dressing. At next visit, the root canal and defect space were filled by MTA. After one day, coronal access was restored by amalgam. Radiography and clinical examination at the two year follow up showed that the tooth was in function and bone repair occurred.

Conclusion: According to these findings, it is possible to have a successful treatment of extensive perforative internal root resorption by MTA without surgery.