Osteonecrosis of the jaw and bisphosphonate use: How big a risk?
Patients with cancer who receive high intravenous doses are at highest risk.
Posted on March 10, 2008
Good dental care is important for everyone, especially men and women with osteoporosis. Healthy habits for your skeleton are also healthy for your jaw bone and teeth.1,2 The safety of the osteoporosis therapies, bisphosphonates, Fosamax, Actonel and Boniva, as well as the metastatic cancer therapies, Zometa and Aredia, have suddenly come into question in the medical field. Despite what you may have read, the skeletal benefits of Fosamax, Actonel and Boniva far out way their rare risks, but these medications are not for everyone. Since all medical therapies and even many over-the-counter agents have some risks, it is always helpful to be as well informed as you can.
Fosamax, Actonel and Boniva increase bone mineral density and reduce your chances of breaking a bone. They are usually well tolerated, yet can occasionally cause indigestion, heartburn and other stomach or intestinal side effects as well as rarely arthritis-like symptoms, weight loss and headaches (none of these symptoms, however, occurred anymore often than they did in women given just placebo in the osteoporosis trials). If you experience possible side effects from your medications or you are worried about your risks, discuss this with your provider and only continue medical therapy if you are tolerating it. Osteonecrosis of the jaw (ONJ) or "death of jaw bone" as you may have heard recently, is an extremely rare devastating condition where an infection of the jaw does not heal. The background rate of ONJ in the general population is actually not known. Though very unusual, it has been seen primarily in cancer patients who have had recent dental extraction and whose cancer has spread to bone where strong cancer medications are needed.3,4
The bisphosphonates used for osteoporosis treatment (Fosamax, Actonel and Boniva) are not thought to be associated with this rare jaw disease, the possible incidence is exceeding low ( < 0.001%). No cases of ONJ have been reported from the Fosamax or Actonel osteoporosis clinical trials in humans or animals, including long-term toxicity and carcinogenicity trials. Some of these trials have now been as long as 10 years (over 100,000 person-years). Of the almost 30 million person-years on these medications all together, as few as 10-25 ONJ cases have been "quoted," yet complete patient information and full reports with risk factors described are not all available. It is estimated therefore that <1 per 100,000 patients or < 0.001% incidence of ONJ may be found in patients on Fosamax, Actonel or Boniva.5
Reports have found that there may be is a 1-2% risk of ONJ in cancer patients6-13 with metastatic bone disease, aggressive breast cancer or multiple myeloma for example, who may have also received chemotherapy, radiation, and/or high dose intravenous bisphosphonates (zoludronate-Zometa and/or pamidronate-Aredia). These medications are used to try and control bone metastasis and Zometa and Aredia are given through an IV in the vein either weekly or monthly at 4 to 10 times the dosages that would be used for osteoporosis, though Zometa and Aredia are not FDA-approved for osteoporosis. There are studies now underway in thousands of cancer patients to better understand the risks of this rare condition. Many cancer doctors or oncologists have always recommended that their patients with metastatic cancer try and have their dental work completed if possible before they receive radiation or chemotherapy, and now they may be adding intravenous high dose bisphosphonate therapy to this recommendation.
At this time, without a history of metastatic cancer, radiation to your bone, poor dental or jaw health or other risk factors affecting your dental health, there should not be a reason to stop bisphosphonate osteoporosis therapy for dental work, nor a reason to withhold dental procedures in someone on Fosamax, Actonel or Boniva. Discussing this with your medical provider and dentist is always recommended since your individual risk factors and dental health is important to review.
The good news is that Fosamax, Actonel and Boniva improve bone density and reduce fractures, and since they have a long action in bone, they should continue to reduce your fracture risk even if you miss a few doses. Nonetheless, not taking bisphosphonate medication exactly how it is recommended and FDA-approved could reduce its beneficial effect long term, so compliance is always key.