A popular online “gringo” bulletin board advertises “holistic dentistry” in Cuenca, and more than one advertisement promotes removal of all silver (colored) amalgam fillings [mistakenly called ‘mercury fillings’.]
Some ads proclaim that amalgam fillings cause “energy interference” and risk for diseases such as Parkinson’s, cardiovascular disease, and even autism.
What are the myths and facts about amalgam fillings?
Why do teeth need fillings anyway?
Tooth decay begins when bacteria in saliva and plaque, a sticky substance found on gums and teeth, interact with sugars and starches in the diet. The result is acid, which can erode dental enamel. Untreated tooth decay leads to holes in the teeth (cavities), infections (abscesses), pain, and tooth loss. The World Health Organization (WHO) reports that tooth decay has historically been considered the most important component of the global oral disease burden, and is still a major public health problem in most high-income countries for children and the vast majority of adults.
“Silver” fillings have been used since the nineteenth century. The American Dental Association estimates more than 100 million amalgam fillings are placed in American mouths yearly and are used around the world.
Amalgam is an alloy of mercury mixed with other metals including silver, tin, and copper. Mercury is what makes the mixture soft enough for it to mold to the hole from your cavity before it stiffens and becomes a part of your tooth. When properly cared for, an amalgam filling can last 15 years or more. Because of the metal alloy used, amalgam fillings offer stronger resistance to damage, making them a superior choice for larger areas of decay.
What happens when you have dental decay?
Dental cavities are treated by drilling out the decayed material and replacing it with a filling, either an amalgam filling or one of the newer types of tooth-colored composite fillings. According to the American Dental Association, you and your dentist will consider what materials to use taking into account the size and location of your cavity. Cosmetic considerations, how long the filling could last, insurance coverage and out of pocket costs are some other factors you might want to consider.
There is a big difference in the hazards of environmental mercury contamination and amalgam fillings. As reported in Toxicology International, mercury is found in the earth’s crust and is ubiquitous in the environment, so even without amalgam restorations, everyone is exposed to the small but measurable amounts of mercury, and can be measured in blood and urine.
Dental amalgam restorations may raise these levels slightly, but the scientific committee of the European Commission reported in 2008 that there was no evidence that dental amalgam caused health problems and warned that much more was known about its safety than newer types of filling.
However, it did say that amalgam was best avoided by pregnant women and children under six.
The main exposure to mercury from dental amalgam occurs during placement or removal of restoration in the tooth. Once the reaction is complete less amount of mercury is released, and that is far below the current health standard. Though amalgam is capable of producing delayed hypersensitivity reactions in some individuals, if the recommended mercury hygiene procedures are followed the risks of adverse health effects could be minimized.
The 2017 Minamata Convention on Mercury, a treaty agreed by the UN Environmental Programme, committed itself to reduce mercury use worldwide, including in dentistry. Norway banned dental amalgam in 2008, Sweden banned the use of dental amalgam for almost all purposes in 2009, and Denmark, Estonia, Finland, and Italy use it for less than five percent of tooth restorations. Japan and Switzerland have also restricted or almost banned dental amalgam. It is available to all dentists in the United States and in Ecuador and in other countries throughout the world.
Although new amalgam fillings are not used in Norway, as reported in Science Norway, we should not be overly concerned about the amalgam fillings we currently have in our mouths. It is noted that the ban on amalgam fillings was less about concern for the safety of those fillings and more about the use and import of toxic mercury. They write that it’s possible to measure mercury levels in both blood and urine, but it’s almost certainly due to the food you’re eating, especially fish and seafood.
What about alternative/composite fillings?
Composite fillings, also known as tooth-colored fillings, are made from a combination of acrylic and ceramic that can be matched to blend with your natural tooth enamel and require less enamel removal and tooth preparation, allowing you to maintain as much of your natural tooth structure as possible. A tooth close to the front of your mouth that is easily seen when smiling or laughing will look more natural with a composite filling. However, silver amalgam fillings are more noticeable, especially when laughing or open-mouth smiling. Over time, amalgam fillings can darken the appearance of the entire tooth, making it appear grayish and dull, negatively impacting the overall look of a smile. For teeth in the back of the mouth that have greater decay, an amalgam filling is the better choice, due to its durability and longevity.
Composite fillings are made of thousands of different substances — most commonly composed of Bis-GMA and other dimethacrylate monomers (TEGMA, UDMA, HDDMA), a filler material such as silica and in most current applications, a photoinitiator. Dimethylglyoxime is also commonly added to achieve certain physical properties such as flow-ability.
Not as durable as metal alloy, composite results generally last about seven to 10 years. Overall, these fillings are considered to be safe and effective. Your tooth may feel more sensitive to cold or pressure for a week or two after you receive a composite resin dental filling. Composite resin dental fillings may be more prone to cracking, breaking, and wearing out than metal fillings, and over time leaks may develop in composite resin fillings. In rare cases, people have developed allergic reactions to composite resin fillings, usually resulting in a localized rash or swelling in the area. Composite resin fillings are also usually more expensive than metal fillings because they take longer to apply.
Should you replace amalgam fillings?
No mainstream dental organizations recommend you replace your amalgam fillings as long as they are in good condition and there is no decay beneath them. Drilling out amalgam will make you lose more healthy tooth and the process will expose you to considerably more mercury vapor than if you left it well alone.
I wrote to Dr. Alan Woods, an American dentist in practice here in Cuenca to ask him this question, after researching this topic. Dr. Wood wrote that unlike many years ago (when his own father was practicing dentistry in the United States) dentists placing amalgam fillings and their staff are operating in a safer environment but that he does not use amalgam, opting instead for either alternative materials or crowns and inlays.
Woods says that gold by far is the best material for dental fillings because it is inert, it doesn’t oxidize, and wears almost exactly like teeth — he sees gold crowns and inlays that have been in place for 50 years and says, “They look as good as the day they were placed.” However, he notes that today’s patients want their teeth to look like teeth, not gold or silver.
Dr. Woods says that composites are good for kids, but because they absorb saliva over time, statistically they have a short life, only about seven years. He says, “Constant replacement over the years is costly — each time [composite fillings] are replaced, less tooth remains, and absorption by saliva and the leakage around the edges has led to a great need for root canals and subsequent crowns.”
Woods notes that porcelain crowns and inlays are another aesthetically pleasing option, but again, there are high associated costs, including materials and time, and the dentist, like all who work with these materials, has to be highly skilled to place these alternative materials correctly.
Woods writes, “We do not have an ideal filling material, though the quest and the promise of success have been around for my entire professional life. There is little evidence that old amalgams release any toxins in normal wear and tear. When removed, there is a release of mercury that needs to be dealt with in the removal process.”
Woods continues, “I am afraid that many dentists view the wholesale replacement of old amalgams as an opportunity for the practice and not so much as a value for the patient. I do not place amalgams, but I do not remove them unless necessary.”
If you’re concerned about mercury in your amalgam fillings, the best thing you can do is keep your teeth healthy and ensure your fillings are still intact.
If your fillings are damaged, they’ll need to be examined by your dentist and will likely need to be replaced. If they aren’t damaged, it’s best to leave amalgam fillings alone at the risk of exposing yourself to more mercury.
Your professional dentist will screen for decay underneath your existing fillings and determine if they need to be replaced. If your fillings do need to be replaced, ask your dentist about their experience removing amalgam fillings. You need an experienced dentist who can safely remove the fillings and provide you with a healthy replacement to continue protecting your tooth.
If you want to learn more about the removal of amalgam fillings, HealthFirstDental in Calgary, Alberta, Canada notes, ” If improperly performed, the haphazard removal of mercury fillings can cause more harm than good. During the removal of amalgam fillings, the patient can be exposed to amounts of mercury, which are a thousand times greater than the EPA allowable concentration. Several precautionary steps must be taken to reduce additional mercury absorption.”
Click here for more information.
Finally, I attended an informative and free webinar just yesterday by the Collaborative on Health and the Environment (CHE). The CHE “cultivates a learning community based on the latest, evidence-based science to share knowledge and resources, and improve individual and collective health.”
The webinar was entitled, ‘Cognitive decline, dementia, and Parkinson’s disease: Environmental contributors and prevention’ and in the Q&A segment I was able to get Dr. Ted Schettler to answer my questions about whether or not it was advisable to have amalgam fillings removed. Dr. Schettler reaffirmed the research that shows that drilling into otherwise healthy teeth to remove amalgam fillings is unnecessary and that for new decay/need for fillings there are other options besides amalgam fillings: speak with your dentist. View the webinar here.
Food, Nutrition, and Your Health columnist Susan Burke March moved to Cuenca after working for more than 25 years as a Registered and Licensed Dietitian and Certified Diabetes Educator in the United States. She currently serves as the Country Representative from Ecuador for the Academy of Nutrition and Dietetics.