Americans just got yet another reason to brush and floss regularly.
It turns out that those tooth-colored materials dentists now use to fill most cavities are made with derivatives of bisphenol A, the controversial endocrine-disrupting chemical used in a wide range of plastic products, including polycarbonate water bottles and food-can linings. Over the past decade, the BPA derivative known as Bis-GMA has been the predominant dental filler, going into the mouths of some 100 million Americans a year, according to one expert. And now a study in the journal Pediatrics is linking Bis-GMA fillings to worse behavioral outcomes in children.
This isn't the first time dental fillings have come under scrutiny. These off-white plastic composites are the supposedly safe alternatives to silvery mercury amalgam fillings, which have raised a number of neurotoxicity concerns. The FDA considers mercury amalgams safe, although countries like Norway and Denmark have banned the use of mercury in fillings (PDF). For largely aethestic reasons, the composite fillings have exploded in popularity and now outnumber amalgam fillings 10 to 1.