Cavities – or dental caries – are a common problem, and the solution that many dentists use are dental amalgams. These are not a brand-new technology, as mercury fillings have been used for about 150 years. Despite repeated concerns about the safety of permanent mercury exposure in the mouth, government bodies have maintained dental amalgams are safe for decades – until recently.

What are Dental Amalgams?

Dental amalgams are used to fill cavities to protect the teeth and prevent them from re-occurring. They are 50% mercury, with the remainder a mix of silver, copper, tin, zinc and other trace metals.

Dental Amalgams, Safety and Health Concerns

Mercury is a natural element and we find levels of it in our water, soil, air and food sources. Exposures to mercury can have negative effects, which I’ll describe in detail momentarily.

When dentists first began using dental amalgams, they believed the mercury in them was inert. Since then, we have learned that amalgams do in fact release mercury vapors as we chew, brush our teeth, grind our teeth, or by natural corrosion. These mercury vapours are then inhaled or swallowed through our saliva, where they have the opportunity to accumulate in our tissues. They can also cross the placenta and the blood-brain barrier.

There has been a heated debate about the safety of dental amalgams for decades. What is truly remarkable is “its safety has never been tested or proven in the United States by any regulatory agency.” Governmental bodies take an ‘innocent until proven guilty’ approach to many compounds and this is backwards: a compound, especially one like mercury that is recognized as toxic, should be proven safe before they enter our food, water, soil and air supply, or be used as medical devices.

Let’s look at some of the evidence that indicates dental amalgams are not an optimal choice.

Amalgams and Children

A 2011 re-analysis of the Childrens Amalgam Trials, which were originally published in 2006 and deemed amalgams safe, found that having amalgams contributed to a greater mercury burden in the body. Subsequent re-analyses of these trials in 2012 and 2013 found an association between amalgams and potential neurobehavioral deficits in children.

Fatigue, Depression and Anxiety

A 2014 review showed a link between dental amalgams and chronic fatigue syndrome, depression, anxiety and suicide.

Autism

Mercury can pass through the placenta. A study of 100 pregnant women determined that women with six or more dental amalgams were three times more likely to have a child with severe autism than mothers who have five amalgams or less.

Autoimmune Diseases

Dental amalgams may trigger an antibody response in patients with autoimmune diseases, and have been noted as an autoimmune risk factor. In one small study of patients with various autoimmune conditions such as lupus, MS and thyroiditis, 71% of those who had their dental amalgams removed reported an improvement in their health.

Dementia

Studies point to a possible connection between amalgams and dementia. In a study of 207,587 seniors, researchers found women with amalgams were more likely to have Alzheimer’s disease than those who didn’t. In an analysis of close to 50,000 dental patients, the authors noted while they didn’t believe there was a direct causal link between dental amalgams and dementia, the fillings accelerated dementia progression in those who were susceptible to it.

As mercury vapors can pass through the blood brain barrier, mercury can accumulate in the brain – and some researchers believe there is a very direct link between amalgams and neurodegenerative diseases such as Alzheimer’s and Parkinson’s.

Amalgams and Dental Professionals

It isn’t just patients with amalgams that are at risk. A study of 180 dentists found that they had four times the mercury levels in their urine than the non-dentist controls. While the majority of these dentists still had levels below health and safety guidelines, researchers note that this is something to monitor and assess to ensure dentists stay safe. An earlier study in 1992 evaluated dentists who had been exposed to mercury vapors with various verbal, visual and coordination tests. The dentists scored anywhere from 3.9% to 38.9% worse on these tests than controls.

Most Recent FDA Recommendations for Amalgams

In the last few decades, countries around the world have banned amalgams, instituted phase-out plans, or placed restrictions on their use. Norway and Sweden banned all use of mercury, which includes dental amalgams, in 2007 and 2009 respectively. In the mid 1990s, Germany advised against their use for pregnant women and children. The European Union set out a plan to phase out dental amalgams by 2030, with many restrictions on their use currently in place.

Here in Canada, amalgams aren’t banned but there are specific considerations that Health Canada recommends, like not using them for pregnant women, children, those with allergies or sensitivities to mercury, those with compromised kidney function, and a few more that you can view at the bottom of this page.

In the United States, the FDA – responsible for hundreds of millions of people – maintained that dental amalgams were safe right up until September 2020. While the FDA isn’t implementing a complete ban on mercury or amalgams, they recommend against using amalgams in specific high-risk populations. This includes pregnant women, women trying to get pregnant, nursing women, children under 6, those with neurological diseases, people with compromised kidney function, and those with mercury allergies. This is huge news, though these restrictions are long overdue as the research about amalgams has existed for decades.

Dental Amalgams and Chemical Synergy

If you aren’t in one of the high-risk groups noted by the FDA and other regulatory government bodies, should you still be avoiding dental amalgams? I would say yes. The challenge with the research on many compounds is that they are tested in isolation. They aren’t evaluated for how they may or may not perform in a human body that is also handling an onslaught of additional heavy metals, obesogens, pesticides, and other chemicals.

Certain foods, when paired together, have a greater effect than if you ate either of those foods on their own. This is called Food Synergy. The same can occur with chemicals in a negative way – this is called Chemical Synergy. The problem with chemical synergy is chemical combinations become more toxic than the chemicals would on their own and this typically has negative consequences for our health.

As one example, we already know that smoking causes lung cancer. However, researchers have found that smokers who are also exposed to asbestos “have a higher risk of developing lung cancer than those only exposed to one risk (either smoking or asbestos alone).”

Each person is unique, and the chemical synergy that occurs may depend on the additional chemicals they are subjected to in the air, water, food, soil, as well as through other avenues like personal care products, cleaning products, kitchen utensils, furniture and other elements in their home. At this point, we cannot predict how the mercury vapors released through amalgams may interact with these extra stressors.

Another thing to consider is it can take up to 14 years for a chemical compound to be identified as a ‘contaminant of emerging concern (CEC)’ and then a further 15 years to conduct in-depth scientific research about it. In the meantime, that compound can be in circulation in our internal and external environments for 30 years before it’s deemed safe or unsafe. We already know that amalgams can put our health at risk – I don’t believe we need to wait another decade for further proof when there is an existing wealth of evidence that calls their safety into question.

Safe Dental Care

If you have existing dental amalgams, it’s best to consult with your dentist (or holistic dentist) about the best approach. Many can be removed safely.

Good oral health can also help prevent cavities from forming. This can be our first and excellent line of defense and includes:

• Brushing our teeth (preferably with natural toothpaste)
• Flossing
• Tongue scraping
• Eating an anti-inflammatory, plant based diet
• Eliminating or reducing sugar and refined flours
• Drinking plenty of water

This is an excellent guide to holistic dental care as well.

As I mentioned earlier, chemicals should be proven as safe before we allow their use – and this hasn’t been the case with dental amalgams. In fact, there is a large body of evidence compiled over decades that indicates amalgams aren’t a safe choice for our health. We can’t wait to try to decrease our chemical body burden: and there’s no better time than right now to do it.