Role of mineral trioxide aggregate in management of external root resorption.

External root resorption (ERR) is a lytic process occurring in the cementum or cementum and dentin of the roots of teeth. Here we report a case of inflammatory ERR in a mandibular right molar in a 22-year-old male patient with history of incomplete root canal treatment with the same. Considering the biological properties of mineral trioxide aggregate cement, especially its alkalinity and sustained calcium hydroxide release, this material was used for the treatment of ERR, followed by permanent prosthesis.