Got a cavity that needs filling? Your dentist might use a dental amalgam filling to seal it up and stop the decay in its tracks. You might have heard rumors about amalgam fillings that contain mercury and could be wondering if it’s safe to put in your mouth. Not to fear – We’re here to help put your mind at ease and answer some of your questions about dental amalgam fillings and their safety.
Dental Amalgam: A Health Risk?
Dental amalgam was once one of the most common materials used to fill cavities. Also known as “silver fillings,” amalgam fillings are silver in appearance but not in composition. Since many dentists now use tooth-colored materials to fill cavities and restore teeth, amalgam fillings are less common than in the past. However, amalgam fillings are more versatile than the newer materials because they can be used for other dental situations and hold up better over time, especially in teeth that undergo wear and tear from pressure and chewing. As the cherry on top, amalgam is more budget-friendly, as it is less costly than other dental materials available.
Some concern has been raised in the past over the elemental mercury used in amalgam (which we will get into soon), but there’s no need to worry. As of 2017, the FDA says that amalgam fillings are safe for adults and children six years old and older. Millions of people have amalgam fillings, and after extensive research and review of amalgam studies, the FDA has not found any reason to limit its use.
Although they are sometimes referred to as “silver fillings,” amalgam fillings are actually made from a combination of metals that make it the most effective and popular filling material used in dentistry for the last 150 years. The combination includes silver, mercury, tin, and copper. Sometimes amalgam always includes small amounts of zinc, indium, or palladium.
You might be thinking, “why use mercury?” Tiny amounts of mercury are used in amalgam because it helps make the filling material flexible. When mixed with an alloy powder, mercury creates a compound that is soft enough to mix and press into the tooth. Another upside is that it hardens quickly and can withstand the forces of biting and chewing over many years.
Since mercury is a metal that occurs naturally in the environment, everyone is exposed to mercury in some form, whether through the air, drinking water, soil, or food. So, having some contact with very low levels of mercury through amalgam isn’t all that much different from other daily exposures.
As with most substances, harm caused by mercury in the body is related to the amount ingested. Low levels of mercury don't cause any adverse effects. But at higher levels, mercury is known to cause several unfavorable symptoms. With amalgam, minimal amounts of mercury in the form of vapor can be released and absorbed into the body as the filling wears.
It makes sense to question whether amalgam is safe to put inside your mouth. However, research has concluded that amalgam fillings are nothing to worry about because the low level of mercury absorbed from them is not enough to create any toxic effects. Studies have shown that the amount of mercury you can be exposed to from amalgam fillings is less than the amount that most people are exposed to in their daily environment or in the food they eat.
Because dentists work with mercury almost every day, they must take safety precautions to avoid negative effects that come with prolonged exposure. Without protection, dentists can inhale mercury vapors, which can produce symptoms over time. They will use protective wear during the mixing and preparation process, but by the time the amalgam is placed in your tooth, the mercury has formed a compound with the other metals and is no longer toxic.
If you would like to explore alternatives to amalgam, you have options you can discuss with your dentist. There is now a dental amalgam that contains indium, which helps retain the mercury, so it’s less likely to release from the filling. There are also high-copper amalgams that contain less mercury and more copper.
If you would like to avoid amalgam altogether, talk to your dentist about other materials like composite resin, porcelain, or gold to restore your teeth. Composite resin can be more visually appealing because it is a tooth-colored material. Still, it also takes longer to set and wears faster than amalgam, which means it might not be recommended in every situation.
There are some cases where it would be best to talk with your dentist about alternatives to traditional amalgam. If you have a known allergy to mercury, are exposed to high levels of mercury daily, or are pregnant, make your dentist aware before having any dental work done. Being transparent with your dentist is the best way to build a treatment plan that is best for you.
Removing amalgam fillings can create more problems than benefits if removal is not necessary. You should only remove or replace amalgam fillings when they're broken, or when there is decay beneath the filling. Removing good amalgam fillings results in unnecessary loss of healthy parts of the tooth and can release more mercury than keeping the filling in place. If you are concerned about existing amalgam fillings, discuss your options with your dentist.
While it’s good to take precautions when deciding what substances you put into your mouth, amalgam fillings are not a cause for worry. However, if you do have any concerns about amalgam, talk with your dentist a, and you’ll be on your way to a worry-free smile once again.
This article is intended to promote understanding of and knowledge about general oral health topics. It is not intended to be a substitute for professional advice, diagnosis or treatment. Always seek the advice of your dentist or other qualified healthcare provider with any questions you may have regarding a medical condition or treatment.