Fosamax, or alendronate, is a bisphosphonate drug, in pill form, marketed by Merck used for the prevention and treatment of osteoporosis and Paget's Disease. Fosamax, like other bisphosphonates, may cause osteonecrosis of the jaw, commonly known as "dead jaw" or "jaw death". It is a severe form of bone damage in the jaw where the bone tissue does not heal after minor traumas. Patients taking Fosamax who undergo dental procedures are especially at risk for osteonecrosis of the jaw. Most cases occur following dental procedures such as tooth extraction, and may be complicated by infection.