Osteonecrosis of the Jaw

What is it?

Recently reports have described a dental condition, ONJ, in which bone in the lower jaw or less commonly the upper jaw becomes exposed, typically after a dental extraction or some other trauma to the jaw, and the wound that occurs fails to heal in the usual time frame. Infection in the area can occur and the area may be painful. This can become a chronic problem in many of those who develop it. With careful dental management, use of antibiotics and daily rinsing of the mouth with antibiotic solutions some patients with the condition do experience healing over time. 

Current information suggests that this condition appears to occur infrequently in patients with cancer and rarely in patients with benign conditions such as osteoporosis or Paget’s disease of bone who are being treated with bisphosphonate medications.

Of the cases reported to date, nearly 95% were cancer patients receiving an intravenous bisphosphonate, pamidronate (Aredia®) or zoledronate (Zometa®), typically given every three to four weeks. A very small number of patients being treated with the bisphosphonate pills alendronate (Fosamax®) or risedronate (Actonel®) for osteoporosis prevention or treatment have also been reported to have developed ONJ. Fosamax® and Actonel® have been available in the U.S. since 1995 and 1998, respectively, and have been used safely by many millions of patients.

Last year the U.S. Food and Drug Administration (FDA) decided that a statement about ONJ would be required in the safety information provided in the package inserts of all bisphosphonate products so that doctors and patients would have this information. 

What are points to consider?

Whenever a medication is prescribed, it is important for the patient to understand both the benefits and the potential risks or side effects associated with that medication.

Fosamax® and Actonel® were approved by the FDA for use in the prevention and treatment of osteoporosis after extensive clinical studies found them to be generally well tolerated and effective in reducing bone loss to prevent osteoporosis and in reducing the likelihood of fractures in patients with osteoporosis.

Based on information available to date, the incidence of ONJ appears to be rare in people taking oral bisphosphonates. It is important however, that patients taking bisphosphonates continue to get regular dental check-ups and to let their dentist know about all the medications they take.

There are reports that some dentists are advising patients to stop the use of bisphosphonates for a period of time (e.g. a month or two) before and after a tooth extraction or implant surgery, but there is no clear evidence, at this time, as to whether this is necessary.

Summary

Based on the currently available information, NOF believes that the benefits of oral bisphosphonate medications outweigh the potential risk of ONJ in the vast majority of patients who are receiving them. Without these medications, patients for whom they are appropriate treatment would be at higher risk of fractures, and fractures are the source of significant pain and disability that impact on function and quality of life. 

NOF encourages all osteoporosis patients taking oral bisphosphonates to discuss their individual situation with their doctor or other health care professional. As clinical information is still incomplete and the causes not fully understood, research into ONJ continues. As new information becomes available, NOF will be providing updates. 

Reference:

Woo SB, Hellstein JW, Kalmar JR. Systematic review: bisphosphonates and osteonecrosis of the jaws. Annals of Internal Medicine. 2006 May 16;144(10):753-61.