Diagnosis of Bisphosphonate-Induced Osteonecrosis (BON) of the Jaw
If an area of exposed jaw bone inside or outside the mouth is seen or felt by a patient taking bisphosphonates, or is seen by their dentist or physician, the patient should be referred to an oral and maxillofacial surgeon as soon as possible. The oral surgeon can diagnose BON and inform the patient about the nature of this condition and the best possible treatment.
Dental Surgery is Associated with Bisphosphonate-Induced Osteonecrosis
In 2003, concerns about dental side effects associated with bisphosphonates were first voiced in the Journal of Oral and Maxillofacial Surgery by Dr. Robert Marx, Chief of Oral and Maxillofacial Surgery at The University of Miami. Dr. Marx reported that he had seen over 30 cancer patients taking intravenous (IV) bisphosphonates who had developed osteonecrosis of the jaw.
These particular cases appeared to occur in patients who were taking IV bisphosphonates and had a dental surgical procedure such as a tooth extraction, periodontal surgery (treatment for gum disease with bone loss) or placement of a dental implant. About 250,000 patients worldwide take IV bisphosphonates such as Zometa and Aredia as part of their cancer treatment regime. The FDA was informed about the cases of osteonecrosis, and consequently required a warning about osteonecrosis of the jaw to be placed on the label of all IV bisphosphonate drugs. To date, one bisphosphonate drug manufacturer, Novartis, has tracked approximately 2,500 BON cases worldwide, with most of the cases involving patients taking IV bisphosphonates for cancer.
Earlier this year, approximately 30 cases of BON were reported in patients taking the oral bisphosphonate alendronate for osteoporosis, which is also known as Fosamax. In a recent article published by Dr. Robert Marx and others from the University of Miami, Bisphosphonate-Induced Exposed Bone (Osteonecrosis) of the Jaws: Risk Factors, Recognition, Prevention, and Treatment, the authors comment that “the current widespread use of alendronate (Fosamax) to prevent or treat early osteoporosis in relatively young women and the likelihood of long term use as well as the ubiquitous presence of dental disease in our society give us cause for concern”. However, Dr. Marx and other experts also note that the benefits of taking bisphosphonates for cancer or osteoporosis far outweigh the risk of developing bisphosphonate-induced osteonecrosis.
Treatment
Currently there is no cure for BON, but treatment is available that can help reduce or eliminate pain, the major symptom of this condition. The most successful treatment currently involves long-term use of an antibiotic such as Penicillin and a chlorhexidine antibacterial mouth rinse. If the patient is allergic to penicillin, a different combination of antibiotics are required. Some other possibilities are ciprofloxacin and metronidazole or erythromycin and metronidazole. In an article by Dr. Robert Marx and colleagues at The University of Miami, 90 percent of patients using this antibiotic regimen were free of pain.
Surgical treatment such as removal of the dead jaw bone has not been found to be successful, and often makes the condition worse. Stopping bisphosphonate use is not an effective treatment because these medicines remain in the bone for many years, even if the medication is no longer being taken.
At this point in time, patients have to be able to and can live with some exposed bone. Treatment is aimed at eliminating or controlling pain and preventing progression of the exposed bone. The necrotic, exposed bone itself is not painful and will remain structurally sound to support normal jaw function.
