Even if you don’t share my penchant for sweets, there’s a good chance you’ve found yourself in the dental chair, mouth agape, with the dentist drilling into your pearly whites to fill a cavity at least once. And, many of these cavities are filled with “silver” or “metal” fillings known as amalgam.
What Are Amalgam Fillings?
Amalgam fillings replace decayed areas in the teeth with metals such as silver, tin, copper, and mercury blended together into a durable, stable, and strong material.
Amalgam holds up well as a dental filling because it remains strong and stable in the moist environment of the mouth and withstands large temperature shifts without degrading. It’s also more affordable and durable than composite resin fillings, which are made from plastic blended with powdered glass. But, the safety of amalgam fillings has been questioned because they contain trace amounts of mercury. And, it seems like more and more boutique dental offices are cropping up, advertising the importance of removing old amalgam fillings to prevent mercury toxicity. Some even claim that having amalgam fillings can cause migraines, chronic fatigue syndrome, and anxiety. Since it often seems like I’m more tired than my activity level should warrant, I started to worry if my fillings could be to blame. Perhaps amalgam is slowly poisoning my body and causing all sorts of health issues—not a comforting thought.
So, to help us make sense of the science, and distinguish between the myths and the facts, we turned to an expert dentist and the body of research on the safety of dental amalgam.
Keep reading to find out if dental amalgam fillings are safe or toxic, if and when you should have them removed, and who to trust.
Meet the Expert
Allison van der Velden, DMD, MPA, is a Doctor of Dental Medicine and the Chief Executive Officer at Community Health Center of Franklin County.
Are Amalgam Fillings Toxic?
“The scientific evidence for the safety of amalgam restorations is overwhelming,” says van der Velden. “Removing them for ‘toxicity’ reasons is actually unethical and can even be grounds for losing your dental license in some cases.” The premier agency in the United States dedicated to dental best practices, the American Dental Association (ADA), along with the FDA, Mayo Clinic, and other notable health agencies all report that dental amalgam is safe. While van der Velden acknowledges that amalgam fillings do contain mercury—which can be considered a dangerous substance—the type and quantity in amalgam fillings is so minimal that it poses no risk. “If you've ever heard the phrase ‘the dose makes the poison,’ you'll know that the concentration makes all the difference and everything is poisonous in the right dose (even too much water can kill a person!),” she explains. “Once the filling is set, all the mercury is chemically bound and stable, so it does not leach into the body.”
Van der Velden says that placing and removing the fillings is the only part of the process that could potentially pose a risk, as there has been some concern about mercury vapor during these processes. “However, despite the theoretical concern, there have been lots and lots of studies on these heavy metal vapors, particularly the effects on dentists and dental assistants who have much higher exposure levels than any patient would due to the fact that they are exposed to it all day long, day in and day out,” notes van der Velden. “There has not been any good scientific evidence to support that theory. They're really safe.”
Can the ADA Be Trusted?
Though van der Velden says she’s had patients tell her that they do not trust the ADA on their statement confirming the safety of amalgam dental fillings, the ADA has employees whose jobs are dedicated to reviewing all the research and defining best practices in evidence-based care. Plus, the ADA is not alone in their position. There are many different disease societies who also have published statements confirming the safety of amalgam. “There’s no motivation to cover up or lie about the safety of amalgam,” reports van der Velden.
When Do Amalgam Fillings Need to Be Removed?
”There are reasons to remove them—namely for cosmetic reasons (they really don't match teeth at all and people prefer white fillings that are more aesthetically pleasing) and if they are failing,” says van der Velden. “For example, if they have a new cavity underneath or a crack, but these problems aren't unique to amalgam fillings, but every material has different strengths and weaknesses.”
Though amalgam fillings have been used for over 150 years, and still have merit, the field of dentistry is constantly evolving and van der Velden says other alternatives have emerged that offer different advantages. “Other materials are now easier to place than they used to be, and just work in a different way, bonding to the tooth chemically instead of mechanically,” she explains. Because alternatives have come such a long way, van der Velden says metal amalgam fillings are not used as much as they once were. “But there is still a time and a place for them,” she notes. “A good dentist chooses the right material for the right situation, and amalgam is still a perfectly good tool in that toolbox.”
Why Do Some Dentists Claim Amalgam Fillings Are Toxic?
“The dentists who claim amalgam fillings are toxic are a vocal and dangerous minority operating outside of scientific best practices,” says van der Velden. “Many of them believe the misinformation, but I suspect more of them realize there is a lot of money to be made replacing healthy fillings for people concerned about toxicity.”
In fact, the quest to make more money seems to be at the root of the rapid spread of the misinformation about amalgam safety and the rising popularity of boutique dental facilities peddling the need for their removal. “There is lots of financial motivation to advocate for the removal of amalgam fillings,” says van der Velden. “I’ve seen people selling phony ‘detox’ treatments, and dentists who do that work can charge a lot for it.”
And unfortunately, these dentists prey upon patients who have bought into some of the unsubstantiated claims and poor advice they’ve found online. “I think often people have an unsolved health or wellness problem and are desperately looking for a solution and then they read misinformation on the internet and become convinced their fillings are harmful,” explains van der Velden, who adds that for such patients looking for answers, advertised “detox” treatments “can give them hope and trust in the wrong sources, which can be a lucrative situation for peddlers of ‘natural’ and alternative remedies.”
So, it sounds like the good news is that we can rest assured that our amalgam fillings aren’t slowly harming our bodies over time. But, I guess it’s back to the drawing board for answers underlying my fatigue. Maybe it’s just the overabundance of these sorts of scares.
The American Dental Association. “Statement on Dental Amalgam.” (2009). https://www.ada.org/en/about-the-ada/ada-positions-policies-and-statements/statement-on-dental-amalgam
The American Dental Association. “ADA reaffirms that dental amalgam is ‘durable, safe, effective’ restorative material.” September 24, 2020. https://www.ada.org/en/publications/ada-news/2020-archive/september/ada-reaffirms-that-dental-amalgam-is-durable-safe-effective-restorative-material