BIPHOSOPHONATES – Complications of Dental Treatments
Bisphosphonates are one of a group of drugs given to post-menopausal women to prevent osteoporosis. Our understanding of bisphosphonates is evolving and is certainly not an exact science at present. What we do know is that Bisphosphonates are not metabolised quickly in the body, and that they remain in bone tissue for many years. If any type of treatment involving surgery to the jaw bone is planned, there is a risk that osteonecrosis may develop if care is not taken to stop the medication and wait for a period of three months.
The cause of this condition is not fully understood. The general mechanism appears to involve a compromised blood supply to the bone. There are risk factors that make an individual more vulnerable to developing osteonecrosis; they include, but are not limited to, corticosteroid use, diabetes, alcoholism, tobacco use, infections and inflammation. Of increasing concern is that bisphosphonates may be associated with a specific form of osteonecrosis of the jaws. In recent years there have been an increasing number of cases reported.
Most cases have occurred after tooth extraction, but can also occur spontaneously and may be associated with pain at the site. The cause of the condition is not defined and may include the possibility of altered blood vessel or bone formation.
For patients on oral bisphosphonate medication, initial studies seem to indicate that three years of therapy makes patients more vulnerable. Most cases of osteonecrosis of the jaw appear to occur in patients who have received bisphosphonates intravenously as part of cancer treatment. The incidence in patients who received intravenous bisphosphonates is 0.8% to 12%. The incidence in patients receiving oral bisphosphonates such as Fosamax® is much lower, 0.01 to 0.04%. After tooth extractions, the incidence increases, but is still small, 0.09% to 0.34%.
The optimal duration of treatment with bisphosphonates has not been defined and there are ongoing studies investigating long-term dosing to determine the best use of this drug. For patients on oral medication, initial studies seem to indicate that three years of therapy makes patients more vulnerable. Studies that have gone up to two years in duration have shown no adverse effects. These studies also suggest that stopping a bisphosphonate for 3 months before a procedure appears to reduce the incidence of osteonecrosis. It is surprising that some bisphosphonate treatment may be associated with osteonecrosis of the jaw while other bisphosphonates have been used to treat similar conditions, for example, osteonecrosis (loss of blood vessels resulting in bone death) of the hip. This suggests that further research is needed to understand the cause of osteonecrosis.
CONSULT US IF YOU ARE TAKING THIS MEDICATION.
