Osteonecrosis of the Jaw

Over the past several decades, several new “anti-resorptive” drugs such as bisphosphonates have been introduced to treat osteoporosis and some types of cancer.  These medications work to decrease the turnover or remodeling activity that naturally occurs in all bones.  While they work well in preventing catastrophic injuries such as hip fractures and spine fractures, a side effect that is now well known called osteonecrosis of the jaw can occur after a surgical dental procedure.  The most common manifestation of this condition is an area of jaw bone that does not heal, but instead becomes devitalized and necrotic after a tooth removal.  This is why the condition is called osteonecrosis, which literally means dead bone.  Symptoms may include foul taste and smell, drainage, discoloration and exposure of the jaw bone, infection, and pain.

Some of the medications that have been known to cause osteonecrosis are listed below:

Bisphosphonates

• Zolendronate (Reclast, Zometa)
• Alendronate (Fosamax, Binosto)
• Risedronate (Actonel, Atlevia)
• Ibandronate (Boniva)

Rank-L inhibitor

• Denosumab (Prolia, Xgeva)

Anti-Angiogenic medications

• Sunitinib ( Sutent)
• Sorafenib (Nexavar)
• Bevacizumab (Avastin)
• Sirolimus (Rapamune)

The risk of developing osteonecrosis while on these medications varies with route of administration (oral vs IV), dosage and length of treatment, type of medical illness (cancer or osteoporosis), local factors (pre-existing dental or periodontal infection), concurrent administration of other medications (i.e. corticosteroids are associated with increased risk of ONJ).  Most of the studies suggest a 1-2% risk of developing osteonecrosis for cancer patients and 100x lower in patients taking antiresorptive medications for osteoporosis.

If your doctor has prescribed any medications to prevent hip fractures or increase bone density, you should notify your dentist or oral surgeon prior to having any invasive dental procedure done – even if it is a simple tooth extraction.  Prevention through careful screening and strategic planning is preferred over management of the condition after osteonecrosis has already occurred.

For more information, please refer to the official position paper from the American Association of Oral & Maxillofacial Surgeons:  2014 AAOMS position paper on MRONJ