Osteonecrosis of the Jaw (ONJ)

Osteonecrosis of the jaw, referred to as ONJ, is development of lesions of the jaw that do heal within 8 weeks. These lesions contain dead tissue of the jaw with overlying areas of swelling and drainage of pus visible in the mouth.

Link with Osteoporosis Medicines

Osteonecrosis of the jaw is an unusual side effect associated with taking any osteoporosis medicines in the bisphosphonate class or denosumab as Prolia or Xgeva. It is rare to have this occur spontaneously with no underlying problem or dental procedure. Most cases had oral surgery or extraction of a tooth associated with development of ONJ. Other factors in addition to may increase risk for ONJ, including poor fitting dentures, periodontal disease, diabetes, steroid use, smoking, and alcohol abuse.

What is Your Risk?

Patients with cancer receiving bisphosphonates or denosumab are at highest risk for developing ONJ, but the rate is still low. An estimated 1 in 10,000 individuals with cancer receiving bisphosphonates develop ONJ. Those patients with head and neck cancer receiving chemotherapy and/ or radiation to the mouth are at highest risk.

The estimated risk of ONJ for noncancer patients taking bisphosphonates is 1 to 10 in 100,000.

Denosumab is a newer medicine used for osteoporosis and in breast and prostate cancer patients. Osteonecrosis of the jaw in osteoporosis clinical trials was identified in only two subjects in the fourth and fifth years of their pivotal fracture trial. In cancer patients with spread to the bone whom are given a higher dose (120 mg) every 4 weeks, a study examining denosumab versus zoledronic acid for the treatment of bone metastases, found no significant difference in the occurrence of ONJ (2.0%, denosumab; 1.4%, zoledronic acid; P=0.39).

In spite of all the lawyer-sponsored advertisements you may have seen or read about taking these medicines and jaw bone problems, the risk of developing ONJ is low and the benefits of these medicines outweigh the risk of ONJ.

Oral Care

A careful examination of your mouth and teeth is recommended before starting a bisphosphonate or denosumab. If you require any oral surgery or removal of teeth, you should have these procedures prior to starting on a bisphosphonate or densomab.

If you are already on a bisphosphonate or denosumab and require any invasive dental surgery, team your doctor who prescribed your medicine and your dental professional together to decide how to proceed. Several organizations have recommendations and guidelines.

Other Resources:

American Dental Association – Osteoporosis Medicines and Your Dental Health
Recommendations from the American Dental Association, November 2011