Earlier in 2014, the American Association of Oral and Maxillofacial Surgeons issued a new position paper on Medication related Osteonecrosis of the Jaw (MRONJ) see http://www.aaoms.org/docs/position_papers/mronj_position_paper.pdf?pdf=MRONJ-Position-Paper. The condition in the past has been called Bisphosphonate-related Osteonecrosis of the Jaw but both antiresorptive and antiangiogenic therapies are associated with it so the name has been updated. MRONJ appears as non-healing exposed bone in the mouth and may affect patients undergoing intravenous cancer-related therapy or those treated with oral or IV bisphosphonates for osteoporosis.
The paper states that patients may be considered to have MRONJ if the following characteristics are present:
- Current or previous treatment with antiresorptive or antiangiogenic agents;
- Exposed bone or bone that can be probed through an intraoral or extraoral fistula(e) in the maxillofacial region that has persisted for more than eight weeks;
- No history of radiation therapy to the jaws or obvious metastatic disease to the jaws.
Most patients on antiresorptive or antiangiogenic agents who develop MRONJ do so after a dental procedure, such as a tooth extraction. The position paper cites several studies which has shown that between 52% to 61% of patients report tooth extraction as the precipitating event who develop MRONJ. It is estimated that the risk of developing ONJ among patients exposed to oral bisphosphonates following tooth extraction is 0.5%. This estimate was based on a prospective evaluation of 194 patients exposed to oral bisphosphonates that underwent extraction of more than 1 tooth. Among these patients, one developed ONJ after tooth extraction. Estimates for cancer patients who develop ONJ after tooth extraction exposed to intravenous bisphosphonates ranges from 1.6% to 14.8% in different studies.
The position paper recommends that any patient who needs to start antiresorptive or antiangiogenic therapy should have the treatment delayed if possible until their dental health is optimized. Further, an oral examination and radiographic assessment should be conducted prior to beginning such therapy in order to identify potential infectious sites. In addition, non-restorable teeth and those with a poor prognosis should be considered for extraction.