The studies released Wednesday and Thursday are not the first that Fosamax -- which also goes by the generic name alendronate -- has weathered in its 13-year existence. Most recently, a study published in April in the Archives of Internal Medicine found that patients taking Fosamax had about an 86 percent increased risk for developing an irregular heartbeat. The study received widespread media attention, despite the fact that much larger studies largely exonerated Fosamax with regard to this side effect.
A statement issued Wednesday by Merck suggested that the latest study suggesting a higher-than-expected jaw osteonecrosis risk is likewise trumped by larger, more thorough studies that have already been performed.
"The study ... has material methodological flaws and scientific limitations, making it unreliable as a source for valid scientific conclusions regarding the prevalence of [osteonecrosis of the jaw] in patients taking alendronate," the statement reads. "In controlled clinical trials involving more than 17,000 patients, contributing as much as 10 years' data with alendronate, there have been no reports of [osteonecrosis of the jaw]."
J. Edward Puzas, a professor of orthopaedics at the University of Rochester School of Medicine and Dentistry, agreed that better studies are needed before doctors and patients can make conclusions about the link between these drugs and osteonecrosis of the jaw.
"Identifying all patients who are on alendronate and then reporting on the incidence of [osteonecrosis of the jaw] in this group does not implicate alendronate in the causation of the [condition]," he said.
"Given the concern of dental community in the use of bisphosphonates, I think a carefully designed cohort study to settle the issue is warranted."
ABC News' Audrey Grayson and Michelle Schlief contributed to this report.