The US Food and Drug Administration warned Thursday that silver dental fillings, known as dental amalgam, may cause health problems for some high-risk groups.

© David Tadevosian/Shutterstock
The FDA warned Thursday that dental amalgam filling may cause health issues for some high-risk groups.

The updated FDA guidance said the filling material could lead to health issues for those with a hypersensitivity to mercury.

Dental amalgam fillings are a mixture of silver, tin, copper and mercury. The FDA and American Dental Association have said for years the material is safe, but advocates have called for a filling material that doesn’t contain mercury since the 1970s.

The FDA’s updated recommendations said dental amalgam is safe for most, but there are some who should avoid the material, including pregnant women and their developing fetuses; women who plan to become pregnant; women who are nursing; children, especially those that are under the age