Osteonecrosis of the jaw (ONJ) is a condition in which an area of jawbone is not covered by the gums. The condition must last for more than eight weeks to be called ONJ. When the bone is left uncovered, it does not receive blood and begins to die. ONJ most often develops after an invasive (surgical) dental procedure such as dental extraction. ONJ also may occur spontaneously over boney growths in the roof or inner parts of the mouth.

ONJ is associated with cancer treatments (including radiation), infection, steroid use, or antiresorptive medications used for osteoporosis. ONJ is much more common in those patients who use bisphosphonates for cancer of the bone treatment. When used for osteoporosis in much lower doses, it is very rare. Our specialist in Oral Medicine, Professor Stefano Fedele, has researched and authored several publications on the this condition.