Risk of Medication-related Osteonecrosis of the Jaw Following Root Canal Therapy in Patients with a History of Bisphosphonate Medication Use

The purpose of this study was to answer the following questions: (1) are patients undergoing root canal treatments who have received or are currently receiving bisphosphonate medications at an increased risk for developing medication-related osteonecrosis of the jaw (MRONJ)? (2) Do patients after receiving root canal treatment undergo extraction despite anticipated risks of MRONJ? A total of 449 unique patients met the initial inclusion criteria. Of which 239 patients (a total of 383 teeth) patients had received oral or intravenous antiresorptive or anti-anxiolytic medications prior to receiving endodontic treatment at the University of Illinois at Chicago dental clinics. These patients’ records were reviewed and documented if the patient developed MRONJ or received extraction after root canal treatment. Outcome was evaluated using functional retention of teeth. A total of 6 patients were diagnosed with MRONJ. Of which, 4 patients had pre-existing MRONJ and were referred for endodontic treatment. 2 developed MRONJ after receiving root canal treatment, but MRONJ developed at sites distant to endodontically treated teeth. 48 patients had teeth (65 teeth) extracted after receiving root canal treatment despite anticipated risks of MRONJ development. None of these patients developed MRONJ after extraction. Root canal treatment is not a contributor to MRONJ development. The primary reason for extraction after root canal treatment was due to restorability of the tooth, and not primarily due to root canal treatment failure.