Dental amalgam is a durable metal alloy that fills and supports a dental cavity. It is often referred to as “amalgam,” “metal fillings,” or as a “silver filling” because of its silver color; however, it’s not entirely accurate to call it “silver,” as dental amalgam is comprised of liquid mercury and a powdered alloy that includes silver, copper, and tin. Because dental amalgam fillings contain mercury, which is a known toxin to the nervous system in humans, it’s important to understand the adverse health risks associated with these types of fillings, the long history of the dental amalgam debate, and why the best practice is to avoid these types of fillings for any future dental caries and remove all existing dental amalgam fillings to help improve the chances of positive health outcomes.
Why Dental Amalgam Is Harmful
Dental amalgam contains approximately 50% of elemental mercury and the other half is a metal alloy. The chemical properties of liquid elemental mercury are such that when combined with the metal alloy, a putty is formed. When placed in the compromised tooth, this putty easily fills gaps, hardens, and lasts for years. What’s key to this mixture is the mercury and what happens to it at room temperature. This odorless liquid slowly evaporates into a mercury vapor at room temperature, and herein lies the issue with dental amalgams: Mercury vapor is a hazard to human health.
Research has shown that acute exposure to mercury vapor by inhalation can cause central nervous system toxicity including tremors, tingling in extremities, memory loss, depression and irritability, and delayed reflexes. Chronic exposure to mercury vapor affects the central nervous system and can cause damage to the kidneys and a number of other organ systems in the body. Because dental amalgam is so sturdy, it can stay in place over 20 or 30 years, allowing a cumulative effect of mercury exposure to occur. Over time, with mechanical manipulation (e.g., chewing, brushing teeth), dental amalgam fillings wear down and off-gas mercury vapor in the mouth, which is then inhaled in the lungs and absorbed through the respiratory system, causing damage to the nervous system, lungs, kidneys, and other parts of the body.
There are many symptoms of possible mercury toxicity from dental amalgam fillings and are dependent on how long the fillings have been in place, how many amalgam fillings one has, and the wear-and-tear of each amalgam filling. Some of the most common symptoms include:
- Headaches
- Fatigue or lethargy
- General weakness
- Autoimmune dysfunction
- Muscle and joint pain
- Hearing loss
- Cognitive impairment
- Tremors
- Dizziness
- Respiratory problems
- Irritability
- Depression and anxiety
- Loss of appetite
- Insomnia
- Red, inflamed gums
- Metallic taste in mouth
The History of the Dental Amalgam Debate
The use of modern dental amalgam fillings in the United States dates back to the 1830s. Prior to its use in the US in the 1800s, dental amalgam fillings made of silver, copper, zinc, and mercury were used in European countries. Going back even further, there is evidence that rudimentary dentistry in China (around 600 AD) used some form of dental amalgam to preserve diseased teeth.
By 1844 The American Society of Dental Surgeons raised concern over mercury poisoning from dental amalgam. So concerned was the association that they asked their members to pledge to stop using dental amalgam fillings altogether. Despite this preventive safety measure, dentists ignored the warnings and continued to use dental amalgam due to its low cost and long-term durability. While these types of fillings remained a mainstay in dentistry for decades, the concern over the harmful effects of mercury in dentistry continued to grow, not only in the US but in other parts of the world, as well.
As early as 1926, a German chemists named Dr. Alfred Stock voiced concerns with the dangers of mercury vapor in amalgam fillings. He published over 50 papers detailing mercury and the effects of mercury poisoning. It wasn’t until 2018 that the European Union banned the use of dental amalgam in children, pregnant women, and nursing mothers, and beginning January 1, 2025 will ban the use of mercury in dentistry and use only mercury-free alternatives instead. Other countries around the world have followed suit in banning or limiting mercury in dentistry, either for public health concerns and/or environmental reasons.
On-Going Public Health Concern with Dental Amalgam
Because of the persistent health concerns with dental amalgam off-gassing mercury vapor in both patients (especially children and pregnant women) and the dental professionals who handle such toxic materials, as well as the environmental repercussions of mercury as a toxic pollutant in soil, air, and wastewater, most dentists in the US have stopped using dental amalgam mercury fillings altogether and have started using safer porcelain, ceramic, or BPA- free composite fillings. Though the use of dental amalgam fillings nowadays is less common, the US Food and Drug Administration (FDA) has not banned them and as such, dental amalgam may still be used because it is durable and a cost-effective material. The FDA, however, does provide the following guidance and recommendations for high-risk populations and the use of dental amalgam: Pregnant women or women planning to become pregnant, nursing mothers, children (especially under the age of 6), and those with compromised immune systems should avoid amalgam fillings.
Wiseman Health Take-Home Advice
When it comes to total health and wellness, we are only as good as our weakest link and it starts with oral health. We need to view maintaining our oral health as important as other foundational health approaches such as eating whole foods, drinking pure water, staying active and exercising, getting appropriate sunlight, and sleeping well.
- To reduce your chances of dental cavities and ultimately, the need for future dental fillings, consume a whole food diet that’s low in sugar and processed foods.
- Most dentists have phased out the use of traditional metal dental amalgam fillings. Should you need a filling, avoid using metal dental amalgam fillings and request less toxic and safer materials such as porcelain, ceramic, and BPA-free composite fillings that are more biocompatible to your body. These safer substances are widely available, safer, durable, and cost effective. They also have the aesthetic benefit of matching your tooth color unlike metal dental amalgam fillings.
- Introducing any foreign substance into a tooth is not completely risk free in terms of toxic load, over time. The goal is to decrease this risk as much as possible with modern biocompatible filling materials that are safer than traditional metal dental amalgams. However, for dental patients who are concerned about which mercury-free dental amalgam alternative is best for them, there is an option to take a dental biocompatibility test for individual needs. With this kind of biological testing, a patient’s blood sample is sent to a laboratory where the serum is evaluated for the presence of IgG and IgM antibodies to the chemical ingredients used in dental products. The patient is then given a detailed summary of the safest dental materials to use and those that could result in a reaction. Two examples of labs that currently offer this service are Biocomp Laboratories and ELISA/ACT Biotechnologies.
- If you currently have metal dental amalgam fillings, best practice is to get them removed and replaced with safer mercury-free materials, not only as a proactive measure for future disease prevention but also to help treat any current chronic long-standing disease or health conditions. Ask your dentist whether they perform this procedure. It must be performed by an experienced, licensed dental professional who can ensure the integrity of the tooth while also safely and effectively disposing of amalgam pieces and mitigating mercury fumes during the procedure.
- If your current dentist doesn’t support this approach and/or is not experienced or certified to take out dental amalgam safely, find a local dentist who does. There is a growing movement within biological dentistry and with biological dentists (or holistic dentists) to align with the tenets of the IAOMT (International Academy of Oral Medicine and Toxicology), which is the gold standard institution for natural, safe dentistry. IAOMT’s recommendations and safety protocol for safe mercury removal is called SMART, or Safe Mercury Amalgam Removal Technique. It’s important to note, per the IAOMT, they do not recommend amalgam filling removal for women who are pregnant or breastfeeding or that dental personnel who are pregnant or breastfeeding conduct work that disrupts or removes amalgam fillings.
- To better understand the purpose of biological dentistry and safer dentistry in general, the IAOMT states the following on its website:
“In using the term biological dentistry, we are not attempting to stake out a new specialty for dentistry but rather to describe a philosophy that can apply to all facets of dental practice and to health care in general: Always seek the safest, least toxic way to accomplish the mission of treatment and all the goals of modern dentistry, and do it while treading as lightly as possible on the patient’s biological terrain. A more biocompatible approach to oral health is the hallmark of biological dentistry.” - For more information on mercury-safe dentistry and to find a mercury-free dentist, see the resources below:
Editor’s Note: This content was created by our Wiseman Health content and writing team, without the influence of artificial intelligence engines. Our goal is to be your trusted source for natural health and medical information.
Park, JD, Zheng, W. (Published online 2012, Nov. 29) Human Exposure and Health Effects of Inorganic and Elemental Mercury. ncbi.nim.nih.gov.
ScienceDirect. Dental Amalgam. sciencedirect.com
The EU Will Ban Dental Amalgam by January 2025. iaomt.org.
Appendix 20 Historical Overview of the Amalgam Debate. ncbi.nim.nih.gov
U.S. Food and Drug Administration. Appendix 1: Summary of Changes to the Classification of Dental Amalgam and Mercury. fda.gov.
The Safe Mercury Amalgam Removal Technique. iaomt.org