Amalgam is a material used in dentistry to fill cavities, also known as “silver fillings” by most patients. It’s a combination of metals like silver, mercury, tin, and copper along with small amounts of zinc, indium, or palladium that has been used for about 150 years in the professional dental field. Most recently, these kinds of fillings have fallen out of fashion in favor of tooth-colored composite to restore teeth, but at a higher cost and greater risk of being damaged from contact with hard foods or drastic temperature changes. Amalgam has a reputation for being stronger and lasting longer at a lower price point, so it’s still very much in use today for people who aren’t as concerned about the aesthetic aspects of tooth restoration. Though amalgam has been in use for over a century, there are many misconceptions about its safety. Authorities on the issue have begun to release statements in regards to common questions people may have about these fillings.
Is it Safe?
Though millions of people have had amalgam fillings without any complication, many people are still concerned with the safety of mercury being implanted into the mouth. Mercury is otherwise an element that’s toxic to humans and can be found in instruments like thermometers. Mercury poisoning is potentially deadly, leading to neurological, gastrointestinal, and renal failure. That being said, the small amount of mercury, when combined with other metals, becomes a stable material that can be safely used in the body. The American Dental Association, U.S. Centers for Disease Control and Prevention, U. S. Food and Drug Administration and World Health Organization (among many others) have all confirmed that, based on extensive research, there are no known health hazards that are brought upon my these silver amalgam fillings. For a comprehensive list of statements on this topic from various organizations and authorities in science and dentistry click here.
Why use Mercury?
Since mercury is otherwise toxic, many people are puzzled at why dental professionals would insist on using this material to create fillings. Mercury does exist in nature as a liquid, and when heated, it becomes a gas. It can also be mixed with many other metals to create a blend. Everyone, at some point, is exposed to mercury in some form through food, water, air, and soil. Most often, people hear about mercury concerns due to the amount of mercury toxicity that is found built up in fish due to pollution. This mercury pollution occurs from industries that heat and burn fuels that contain mercury, releasing it into the air. After prolonged exposure to the air and water, mercury can build up in the body.
In dentistry, when mercury is mixed with an alloy powder, mercury helps create a pliable metal that can be pressed down onto the tooth that will provide a natural-feeling bite for the patient. While soft and malleable, it also hardens quickly. Amalgam fillings are very durable and are often recommended for molars and back teeth because of their ability to withstand biting, chewing, and large amounts of pressure.
Though exposure to mercury is often inevitable, context is important in regards to the alarm surrounding amalgam fillings. Very low levels of mercury, like those used in silver fillings, have no profound effect on the body. In fact, people who eat vast amounts of mercury-contaminated fish are at a much higher risk of adverse effects than people who amalgam fillings. People who work jobs where they are exposed to mercury gasses are also at greater risk, especially neurological.
The biggest misconceptions surrounding the mercury in amalgam fillings is that people believe these fillings can “release” mercury into the bloodstream and body. However, the very small amount of mercury vapors that may come off amalgam fillings is so minuscule that it’s nearly negligible. In fact, some researchers claim that the small is amount is even less than people are exposed to any given day in their natural environments.
Because dentists are exposed to the mercury in amalgam almost every day during their jobs, they must take these precautions as their exposure is much greater than the average patient’s. For some perspective, an average dentist may have to mix up to fifteen to twenty amalgam fillings a day, exposing them to small amounts of mercury gases each time. This is a much higher rate than natural, so their safety gear and precautions are not because the amalgam fillings themselves are dangerous, but because of the mixing process to create the fillings themselves. By the time a dentist creates the filling mixture and applies it to a patient’s tooth, it is no longer toxic because it has been stabilized by the other metal materials in the mix. Dentists are also careful with the disposal of their amalgam mixing materials to minimize the impact on the environment.
Reactions to Amalgam
In very rare cases, there are people who have allergic reactions to amalgam, but there have been fewer than 100 cases ever reported of such occurrences. In these extreme cases, other filling materials can be used, such as composite, gold, or copper amalgams. Though mercury amalgam fillings have been deemed safe for pregnant women, mercury can penetrate the placenta, so they are urged to avoid any extensive dental work while pregnant or to choose an alternative option to avoid any possible contamination.
Scientists and dental medicine authorities have been working to disprove the myths surrounding amalgam fillings, but there are some people who insist on having theirs removed. Although unnecessary, some have gone as far as looking into amalgam-free practices far away from their area. Removal of these fillings, unless they are cracked or broken, can further damage the tooth and potentially release more mercury than they would in their natural lifespan. For people concerned about amalgam fillings, they are urged to speak with their dentist to see if there are alternative options for filling materials. Amalgam is otherwise proven to be a safe method for filling cavities in people over six years of age.