Considering that millions of Americans have “silver” mercury fillings embedded in their teeth, a recent government hearing on their safety should have been a slam-dunk.
Instead, the advisory panel concluded that a Food and Drug Administration report suggesting that amalgam fillings are safe was “unreasonable” and that further study was needed.
Technically, “unreasonable” doesn’t mean unsafe. The American Dental Association still steadfastly maintains that amalgams should be an option for decaying teeth.
But the panel found the safety report was murky and misleading in some areas, which raises some serious questions, such as, “Why do we put a known neurotoxin in teeth?”
It’s the same question some were asking nearly 200 years ago, when, in 1843, the American Society of Dental Surgeons, concerned about mercury poisoning, required its members to promise not to use amalgam. In 1859, the rival ADA was formed by dentists who believed amalgam was “safe and effective.”
Today, we’re left wondering if that’s really the case. The FDA panel found a startling lack of research on the safety of fillings, especially when it comes to risk of mercury-filling exposure to pregnant women and children, immune-compromised individuals or other “hypersensitive” populations. Dental amalgam contains about 50 percent elemental mercury, in addition to metals such as copper, tin and zinc. Studies have shown that with time, mercury vapors leach out of the fillings. Some critics contend that they are absorbed into the bloodstream. When not encapsulated, the material itself is considered a hazardous waste.
But most dental experts say that when it’s bound to other metals, it doesn’t pose a risk.
The bright spot in this 200-year-old controversy is that the use of “silver” fillings has dropped nearly 40 percent since 1979, thanks in part to better oral care that decreased the overall frequency and size of cavities. Better diagnostics allow dentists to find cavities earlier, when they are much smaller and easier to restore with alternative materials.