Fosamax, a bisphosphonates, is now linked to the death of jaw bone tissue. Two other Bisphosphonates are more likely to cause this tissue death: Zometa and Aredia.

Fosamax, Actonel, and Boniva are used to treat osteoporosis, but also raise the risk of jaw necrosis.

Bisphosphonate drugs block the normal ``turnover" of bone cells. Because bone is not turning over, infections in the mouth (which is loaded with bacteria), may not heal properly, further damaging the jaw.

According to the May Annals of Internal Medicine, researchers from Brigham and Women's Hospital linked jaw necrosis to bisphosphonates.

Patients are suing Merck & Co., the maker of Fosamax. But the company on its website noted that as of March 2006, jaw necrosis probably occurs in less than one in every 100,000 patient-treatment years. Last year, the US Food and Drug Administration asked Merck and the other makers of oral bisphosphonates to mention the jaw necrosis risk on its product labels.