We would like to thank Dr. Wolf for his comments regarding our article on bisphosphonate-associated osteonecrosis (BON). Our objective was to provide the general dentist with the best information available at this time on this important issue. We felt that JADA was the best venue to reach the largest number of dentists in the United States and around the world.
We tried to make it clear from the outset that there are more questions regarding BON than there are evidence-based answers. Because this is a relatively new entity, there have been no prospective studies or clinical trials that show that any one modality of treatment is superior to another.
We do know that extensive surgical excision has not consistently led to resolution of the lesion and may have caused progression. We have refrained from publishing anecdotal data because, in the absence of well-controlled trials, those data may not be accurate, may be misleading and, in time, may prove to be detrimental to our patients’ oral health care.
However, it is clear from the data to date that cancer patients exposed to intravenous bisphosphonate therapy are at higher risk of developing this complication. However, anecdotal reports of patients taking elective alendronate therapy developing BON continue to trickle in.
Although there are a few reports of osteonecrosis in the generally healthy patient with osteoporosis taking alendronate, we do not know what the incidence is, we do not know how to identify which patients will develop this condition, and we have not been able to meas ure the risk to these patients. What we must do for our patients taking alendronate for osteoporosis or osteopenia is to inform them about the possibility of developing this complication after invasive dental therapy, again being honest about what we do and do not know.
We are encouraging our colleagues to discuss this possibility with patients, using the information available in the literature, and to obtain informed consent before dental procedures that reflects a consensus decision on the treatment plan to be provided to patients.
Although there are no data on this as yet, the pharmacodynamics of bisphosphonates suggests that the longer one is taking the drug, the more bone turnover is suppressed, and risk of developing BON increases. A patient who has received alendronate for more than 10 years is likely to be at higher risk than one who has received it for one year. However, what other comorbid factors contribute to BON for any given patient have yet to be determined.
As we mentioned on page 1664, "patients who have been given oral bisphosphonates [alendronate, risedronate] within the last three months should undergo dental evaluation. Anecdotal evidence points to a low incidence of BON’s occurring less than six months after the beginning of bisphosphonate therapy." Therefore, symptomatic or nonrestorable teeth and other needed dental treatment can, and should, be provided as soon as possible before the risk of developing BON increases.
For patients who have taken the medication for longer than six months, there are no data available in the literature to help us predict the risk of developing BON. In this case, routine standard of care should be applied and, if there is consent from the patient, the needed therapy should be provided. The anticipated benefit to the patient outweighs the risk of BON development.
Patients should be carefully monitored postoperatively, until the surgical sites are completely healed. Proper maintenance follow-up and oral hygiene care are important to minimize the risk of future additional complications. We encourage colleagues in private practice to document and report cases of BON in this population in the scientific literature, and to submit any adverse drug incident report to the U.S. Food and Drug Administration. We also agree that for the patients taking oral or intravenous bisphosphonates on a long-term basis, conservative dental therapy is preferable to surgical procedures, for obvious reasons.
Consensus among those working in this area will only be possible when more scientific information becomes available, and evidence-based guidelines can be developed. So far, the best we can offer is expert opinion, and that is what we feel we provided in our article.
