Some people may be concerned regarding the safety of mercury in amalgam fillings. It is known that a miniscule amount of mercury vapor is released from amalgam when the restorations are placed or removed, and through chewing and tooth grinding. Many opponents of amalgam have blamed the substance for a variety of general health problems (e.g., nerve damage, autism, Alzheimer’s disease, multiple sclerosis, kidney problems, birth defects, compromised immunity).

However, according to the American Dental Association (ADA), U.S. Centers for Disease Control and Prevention (CDC), National Institutes of Health (NIH) and the U.S. Food and Drug Administration (FDA), there is no sound scientific evidence of a link between amalgam and these or any other health problems. The amount of mercury vapor that escapes from amalgam is too small to cause harm. In addition, dentists generally use measures to remove the vapor from the patient’s mouth (e.g., evacuators that suck out the vapor) during placement or removal. Including the metal indium in the alloy further reduces the amount of mercury vapor released.

According to the Academy of General Dentistry, patients absorb larger amounts of mercury from air, water and foods than from amalgam fillings. The ADA has stated that even a mercury-sensitive patient would need nearly 500 amalgam fillings to notice subtle symptoms of mercury poisoning.

Nevertheless, the controversy has prompted many patients to seek the removal of amalgam fillings in the hope of a miracle cure for another medical condition. There is no scientific evidence that such cures actually occur. Furthermore, the unnecessary removal of any restoration can cause increased damage to the tooth.

Human error and limits in knowledge and technology make it impossible to absolutely state that any substance, including amalgam, is completely safe. However, according to the ADA, amalgam has been more thoroughly studied than any other dental restorative material. The CDC points out that other materials, including composite resin, may also possess dangerous components that may eventually be linked to general health problems.

Since the dangers of amalgam cannot be completely ruled out, it may be recommended that pregnant women avoid amalgam fillings. If a cavity needs to be restored during pregnancy, an alternative material (e.g., composite resin) can be used. Dentists generally urge pregnant women to avoid any unnecessary dental procedures, including removing fillings that are not faulty or defective.