Osteonecrosis of the Jaw: Weighing Your Risk

A troubling jaw disease that may be related to the use of some of the most commonly used osteoporosis medications has been the subject of many news stories and law firm commercials lately.

The disease is “osteonecrosis of the jaw” (ONJ) and the medication in question is a family of drugs known as “bisphosphonates”.

However, the risk of ONJ for osteoporosis patients taking these types of drugs is very low – much lower than the risk of breaking a bone. Most of the people who have gotten ONJ while taking bisphosphonates have been cancer patients taking large doses of the drugs intravenously (directly into the vein).

What is osteonecrosis of the jaw?

The word “osteonecrosis” literally means “bone death”. People with ONJ have areas of exposed bone usually in the lower jaw. They may also have painful ulcers in the tissue of the jaw.

What medications could be connected to osteonecrosis of the jaw?

A family of medications called “bisphosphonates” seems to be connected to some cases of ONJ. Some bisphosphonates are taken in pill form by mouth. Fosamax (Alendronate), Actonel (Risedronate), and Boniva (Ibandronate) are all this type of bisphosphonate.Other bisphosphonates are given intravenously (directly into a vein). Zoledronic acid (Zometa) and pamidronate (Aredia) are this type of bisphosphonate. Boniva can also be given intravenously. Most of the ONJ cases connected to the use of bisphosphonates have involved zoledronic acid or pamidronate.

Can osteonecrosis of the jaw be prevented?

There is no known prevention of ONJ. However, to reduce the risk, all patients taking bisphosphonates should get regular dental checkups. Any infections in the mouth should be treated and any major oral surgery should be completed before starting bisphosphonates in people who are thinking about starting osteoporosis treatment.

Can osteonecrosis of the jaw be treated?

While there is no specific treatment for ONJ, it can heal on its own with the help of antibiotic rinses and avoiding any other dental surgery. But healing is not guaranteed.If you’re on an osteoporosis drug like Fosamax, Actonel, or Boniva, how worried should you be about getting ONJ?

  • The number of known cases of ONJ is small. From 1966 to 2006 there have only been 368 known cases. There is a possibility that there could be more patients with ONJ if some cases have not been reported.
  • Most bisphosphonate-related cases occur in people with cancer. Of the people who have been diagnosed with ONJ caused by a bisphosphonate, 94% of them have been cancer patients and were being treated with zoledronic acid or pamidronate. The bisphosphonates are often used to treat people with certain types of cancer as part of their chemotherapy and the doses are considerably higher than the dose osteoporosis patients are taking.
  • Most of the cancer patients who got ONJ had cancers that had spread to the bones. Of the cancer patients who got ONJ, 84% of them had a cancer that had spread to the bones.
  • Most of the cases occurred in patients who had had recent dental surgery such as a tooth extraction.

Take Home Messages:

  • The people at highest risk for ONJ in patients taking bisphosphonates are people who have cancer that has spread to the bones and are being treated with the intravenous bisphosphonates zoledronic acid or pamidronate. The people at highest risk had also had dental procedures such as tooth extractions.
  • For the typical osteoporosis patient taking Fosamax, Actonel, or Boniva, the chances of breaking a bone are much higher than getting osteonecrosis of the jaw. One out of 3 people with osteoporosis will have a broken bone in his or her lifetime. Experts presently estimate that 1 out of 100,000 people with osteoporosis (who do not have cancer) will get osteonecrosis of the jaw.
  • If you are taking one of these medications, discuss with your doctor any upcoming dental procedures you may be considering.
  • Get any dental infections treated immediately. Be sure to report any noticeable changes in your mouth – pain, swelling, exposed bone – to your dentist and osteoporosis doctor immediately.
  • If you are planning to start taking a bisphosphonate because you have osteoporosis, get any major dental procedures you need before you start.

American College of Rheumatology Hotline. June 1, 2006.