Bisphosphnates were introduced to the drug market in mid 1990’s. They were originally marketed as an alternative to hormone replacement therapies of osteoporosis and to treat osteolytic tumors, breast cancers and to slow down tumor growth. Currently the IV form is used in bone and breast cancer patients. In early 2000’s dentists and oral surgeons noticed post extraction Osteonecrosis of the jaw (ONJ) in patients on bisphosphonate medications. Bisphosphonates work primarily by inhibiting bone remodeling (reduction of osteoclastic activity). They may also reduce vascularization of the wound leading to poor healing process. Radiographs may not show the breakdown of the jawbone until it has reached 40%.
There are two methods of bisphosphonate delivery, oral or IV. Aredia and Zometa are examples of intravenous bisphosphonate. Fosamax , Actonel and Boniva are the most commonly used oral medication for osteopenia and osteoprosis. Since most of these drugs are prescribed by the family medicine and the obstetricians, dentist should inform these practitioners about the oral side effects of these drugs and encourage complete oral exams and removal of any non-restorable teeth prior to bisphosphonate therapy. Patients must also be educated and warned about possible side effects of the IV form of bisphosphonates. Most bisphosphonates have half-life of nearly 7-10 years. Patients on the oral form of the bisphosphonate medication have less chance of acquiring ONJ,especially if it is less than three years of usage.
Following are links to three websites that discuss the Bisphosphonate Osteonecrosis of the jawbone and treatment suggestions.