Silver tooth fillings, also called amalgam fillings, have been used in dentistry for over a century. These fillings are made from a mixture of metals, including silver, tin, copper, and mercury. Dentists have long used amalgam because it is strong, durable, and cost-effective. Many patients have silver fillings in their back teeth, especially in molars that need to handle strong chewing forces.
But over time, people have started asking an important question: Are silver fillings safe? In recent years, concerns have grown about the possible side effects of these fillings—mainly because they contain mercury. Mercury is a toxic element, and its presence in dental fillings has led to debates among patients, dentists, and health experts.
In this article, we will explore the side effects of silver tooth fillings in detail. We’ll explain what amalgam is, why it’s used, and what risks it may carry. Our goal is to provide clear and simple information that helps you make informed decisions about your dental care.
What Are Silver (Amalgam) Fillings Made Of?
Before we dive into the side effects, let’s look at the composition of silver fillings.
Dental amalgam is a mix of several metals. Here is a typical breakdown:
- Mercury (about 50%)
- Silver (about 22–32%)
- Tin (about 14%)
- Copper (about 8%)
- Other metals, in smaller amounts
Mercury is used to bind the metals together. It makes the filling soft enough to mold into the cavity, and then it hardens quickly to form a durable surface. Once set, the filling becomes stable and strong enough to last for many years.
Why Dentists Use Silver Fillings
Amalgam fillings are still used in many dental clinics, and here’s why:
Strength: They can withstand strong biting and chewing forces.
Longevity: Silver fillings can last for 10 to 15 years or more.
Cost-effective: They are generally cheaper than other materials like composite (white) fillings.
Speed of placement: Dentists can place them quickly and easily.
Despite these benefits, silver fillings also have potential drawbacks. Now let’s take a closer look at the side effects that some patients experience.
Common Side Effects of Silver Fillings
1. Allergic Reactions
Although rare, some people are allergic to metals found in amalgam fillings. Symptoms may include:
- Itching or rash in the mouth
- Swelling of the gums or lips
- Burning sensations
These reactions are often linked to mercury or other metals like tin or copper. If you have a known allergy to any metal, you should talk to your dentist before receiving an amalgam filling.
2. Tooth Discoloration
Over time, silver fillings can stain the surrounding tooth. This results in a dark or grayish hue that may affect the tooth’s appearance. This discoloration does not mean the tooth is decaying, but it may look unattractive, especially if the filling is visible when you smile or talk.
3. Cracks and Fractures in the Tooth
Amalgam fillings expand and contract with temperature changes. For example, eating hot food causes the filling to expand, while cold drinks cause it to contract. These small movements can put stress on the tooth over time. In some cases, the tooth may develop tiny cracks, or even break.
This is more likely to happen in larger fillings or older fillings that have weakened. Cracks can lead to pain, sensitivity, or the need for more dental work like crowns or root canals.
4. Tooth Sensitivity
Some patients experience sensitivity to hot, cold, or sweet foods after getting a silver filling. This sensitivity usually fades within a few weeks, but in some cases, it can last longer. If the sensitivity continues or worsens, your dentist may need to replace the filling or recommend another treatment.
Controversial Side Effect: Mercury Exposure
What Is the Concern?
The biggest concern about silver fillings is the mercury content. Mercury is a heavy metal that is toxic in high doses. It can affect the brain, kidneys, and nervous system. The main fear is that mercury from fillings could be released into the body, especially when chewing, brushing, or grinding teeth.
Over time, tiny amounts of mercury vapor may be released from amalgam fillings. You may breathe in this vapor or absorb it through your mouth tissues. In healthy people, the body usually clears small amounts of mercury without causing harm. But some people worry that long-term exposure could lead to health problems.
Are Silver Fillings Safe?
Health organizations, including the American Dental Association (ADA) and the World Health Organization (WHO), have reviewed the evidence.
Most agree that amalgam fillings are safe for most people. However, they also note that some groups may be more sensitive to mercury exposure.
These groups include:
- Pregnant women
- Nursing mothers
- Children under age 6
- People with kidney disease
- People with mercury allergies or sensitivities
For these patients, many dentists now prefer to use mercury-free options, such as composite resin, ceramic, or glass ionomer fillings.
Environmental Impact of Mercury in Dentistry
Mercury in dental offices can also affect the environment. When amalgam waste is not disposed of properly, it can enter the water system. This has raised concerns among environmental groups and led to stricter rules for handling dental mercury in many countries.
Some dentists now use amalgam separators, which collect and store mercury waste safely before it reaches the plumbing system. This helps reduce the environmental impact of using silver fillings.
Should You Remove Old Silver Fillings?
If you already have silver fillings, you might wonder whether you should get them removed. The answer depends on your situation.
Most dentists agree that you should not remove silver fillings unless there is a specific reason. These reasons may include:
- The filling is broken or leaking
- You have signs of a metal allergy
- You are experiencing unexplained health symptoms that may be related to mercury
- You simply prefer a more natural look
Removing amalgam fillings can actually release more mercury vapor than leaving them in place. That’s why it’s important to work with a dentist who uses safe removal techniques, including:
- High-speed suction
- Protective barriers
- Air filtration systems
- Proper waste disposal
If your fillings are working well and you’re not having any problems, most dentists recommend leaving them alone.
Safer Alternatives to Silver Fillings
If you need a new filling or want to replace an old one, there are several alternatives to amalgam:
Composite Resin Fillings: These match the color of your teeth and are often used in visible areas.
Ceramic Fillings (Porcelain): More durable than composite, and very natural looking.
Glass Ionomer: Releases fluoride to protect the tooth, but less durable than composite or ceramic.
Gold Fillings: Long-lasting and biocompatible, but very expensive and visible.
Talk to your dentist about the best material for your specific needs. The right choice will depend on the size of the cavity, location in the mouth, budget, and cosmetic preferences.
Conclusion
Silver fillings, or amalgam fillings, have been used in dentistry for over 100 years. They are durable and cost-effective, but they come with certain side effects. Common issues include tooth discoloration, allergic reactions, and cracks in the teeth.
The biggest concern remains mercury exposure, especially for vulnerable groups.
Most health experts agree that silver fillings are generally safe for the average person. However, if you are concerned about mercury, or if your fillings are causing discomfort, it may be worth exploring other options. Today’s dentistry offers safer, more attractive alternatives that do not contain mercury.
