Mercury toxicity: Are my metal fillings putting me at risk? | Dr. Rich

A recent KING-5 HealthLink story explained how metal fillings could make you sick.

We haven't provided metal fillings in our practice for more than 12 years now. As the story explains, metal amalgam fillings contain mercury, a toxic heavy metal. Although not everyone agrees whether this is a health issue or not, it just makes sense to avoid.

You have been advised for years now to not eat certain types of predator fish like tuna and swordfish more than a couple of times per week. The reason is simple: they eat other fish and thus tend to concentrate the toxins ingested by other fish in their own flesh. Mercury toxicity from various forms of pollution affects the ocean and thus the sea life that call it home.

If you have tried to find an old-style glass thermometer, you've likely found it difficult. Even some electronics, such as home thermostats and compact fluorescent light bulbs, contain small amounts of mercury. That's why we are all encouraged to recycle those items appropriately and to keep out of the regular trash. We don't want the mercury from discard items ending up in the landfills, as it can eventually leach into the groundwater and contaminate our precious drinking water.

I find it ironic that government agencies, like the FDA, continue to insist that metal dental filling materials that contain mercury, are safe for human mouths. Yet, on the other hand, mercury is highly regulated by the same agencies, and it is considered toxic if it gets into the environment. What about the environment that is your mouth?

As a dentist, I see patients every day who need to have old failing mercury fillings removed due to decay or fracture. In order to do that, we use lots of water and high-velocity suction to immediately rinse out the pieces of old filling and other debris as they are removed.

Did you ever wonder what happens to all of that old filling material? Rest assured that it doesn't simply go down the drain. As Gill, a character in the classic Pixar movie, "Finding Nemo", says, "All drains lead to the ocean, kid!"

What you can't see during your dental appointment is the sophisticated trap and filtering system that removes all mercury containing waste before allowing the remaining fluids to continue on down the drain. Periodically we pay to have a certified technician service the system. He removes the captured mercury debris and safely packages it for processing by a federally regulated and insured hazardous waste processor. For something that is supposedly safe to use in your mouth, that's a lot of regulation and required safety steps once it leaves your mouth.

I made the decision over a decade ago to discontinue using amalgam fillings in my practice. Since I wouldn't place mercury containing fillings in the mouths of my office team or our families, I couldn't see offering it as an option to my patients.

We use the latest generation of micro-mechanically bonded composite materials. Not only are they tooth colored, they also bond themselves to the remaining tooth structure, which adds much of the strength back to the area of the tooth that was lost when the decay was removed. That reduces the chance of a tooth fracturing in the future and requiring a crown.

Metal fillings do have a few advantages. The materials are cheaper to purchase, easier for the dentist to place and are quite durable. However, as the filling material ages, it corrodes, like many metals. Have you ever noticed how rusty metal appears raised up or thicker than new metal? The same thing happens in your mouth. The metal expands as it corrodes. This expansion puts additional pressure on the remaining walls of your tooth. Eventually, one of those walls will fracture from the combined pressure of the expansion, as well as the heavy biting pressure we place on our back teeth.

This is very similar to the metal wedge a person uses on a round log to split it into firewood-sized pieces. By hitting the metal wedge repeatedly with a sledge hammer, it is driven down into the wood, resulting in a split. If you're lucky, it splits it completely in half. However, if it's your tooth instead of the firewood, the results are catastrophic and the tooth must be extracted.

I am not suggesting that you have all of your mercury fillings removed. If the tooth shows no signs of decay, excess corrosion or cracks, it's probably fine to leave it alone. However, I recommend that you consider not having any more silver fillings placed, and ask your dentist to check for any fractures that may be developing on teeth with large old metal fillings. Although your dentist may recommend a crown if they find any, it's far less expensive and painful than waiting for it to actually fracture. If that happens, you'll still need a crown and possibly even a root canal or an extraction if it breaks too severely.

You wouldn't drive on old tires until they were completely bald and went flat. Not only would it be dangerous to have a blowout at freeway speeds, it might also cause other damage to your car or involve you in an accident that would be far more costly than your tires. Don't wait for your tooth to blow out either.

If you have questions about the mercury in amalgam fillings, composites, crowns or any other dental-related question, feel free to contact Dr. Stuart Rich's office for more information at 253-939-6900,, or

We encourage an open exchange of ideas on this story's topic, but we ask you to follow our guidelines for respecting community standards. Personal attacks, inappropriate language, and off-topic comments may be removed, and comment privileges revoked, per our Terms of Use. Please see our FAQ if you have questions or concerns about using Facebook to comment.

Read the Oct 21
Green Edition

Browse the print edition page by page, including stories and ads.

Browse the archives.

Friends to Follow

View All Updates