Lead author Jeffrey Fellows of the Kaiser Permanente Center for Health Research and colleagues examined medical records for some 600,000 patients, part of the Dental Practice-Based Research Network, a consortium of practices and dental organizations that works to advance knowledge of dental practice.
"Oral bisphosphonates, usually prescribed for osteoporosis patients, appear to increase the risk of osteonecrosis of the jaw, but the risk is still very low," Fellows says in a statement. "Previous studies suggested that about 1 percent of oral bisphosphonate users may develop osteonecrosis of the jaw, but our study found a much lower rate, less than one-tenth of 1 percent. The risk is still real and patients should take necessary precautions, but they shouldn't be alarmed."
A 2009 paper in the American Journal of Health-System Pharmacy found 4.7 million Americans are taking oral bisphosphonates, Fellows says.
The current paper, published in the Journal of Dental Research, examined electronic medical records of 572,606 patients from 1995 to 2006 and found 23 cases of osteonecrosis of the jaw -- most among patients who were not taking oral bisphosphonates, but linked to risk factors including cancer, head and neck radiation therapy and osteoporosis.
Nearly 4 percent of the patients, or 21,164 people, were prescribed oral bisphosphonates, but only six, or about one in 3,500, developed osteonecrosis of the jaw.