Are Amalgam Fillings Safe?

What You Should Know About Mercury Fillings

If you have an old silver-coloured filling, you’ve probably heard conflicting opinions about whether it’s safe. Some people have had amalgam fillings for decades without any problems. Others are concerned about the mercury they contain, especially with more dentists now offering tooth-coloured alternatives.

So, are amalgam fillings safe, and should you consider having yours removed?

The short answer is that existing amalgam fillings in good condition are generally considered safe for most people, based on the available scientific evidence. Although they contain mercury and release small amounts of mercury vapour, research has not established that these fillings cause harmful health effects in the general population.

However, there are important precautions for certain groups, and the UK is gradually moving away from using amalgam for new fillings.

In this article, we’ll explain what amalgam actually contains, what the research says about its safety, why its use is being phased down and whether replacing your old metal fillings with white composite fillings is a good idea.

What Are Amalgam Fillings?

Dental amalgam has been used to repair teeth affected by decay for more than 150 years. You might know it as a silver filling because of its metallic appearance, although silver is only one of the metals it contains.

Amalgam is made from a mixture of metals, typically including:

• Mercury
• Silver
• Tin
• Copper

Approximately 50% of dental amalgam by weight is mercury.

Mercury is used because it reacts with the other metals to produce a material that can initially be moulded into a cavity and then hardens to form a strong, durable filling.

Once set, amalgam can withstand considerable chewing pressure, which is one reason it was traditionally used so widely in back teeth.

However, the fact that a filling contains mercury understandably raises questions about long-term exposure and whether modern alternatives might be preferable.

Are Amalgam Fillings Safe?

For most people, the current scientific evidence supports the safety of dental amalgam fillings that are in good condition.

The British Dental Association recognises amalgam as an established restorative material, and the UK government has described it as safe and effective when appropriately used.

Research reviewed by regulatory authorities has not established that exposure to mercury from dental amalgam causes harmful health effects in the general population.

That doesn’t mean there are absolutely no risks or that every patient is equally suited to amalgam. Some people may have an allergy or sensitivity to its components, while particular medical circumstances warrant additional caution.

It’s also important to distinguish between a filling that’s functioning normally and one that’s cracked, loose or affected by decay. A damaged filling can cause dental problems regardless of what material it’s made from.

If you’ve had silver fillings for many years and they’re still in good condition, their age alone isn’t a reason to assume they’re dangerous.

Is the Mercury in Amalgam Fillings Dangerous?

Mercury is a toxic substance at sufficient levels of exposure. However, understanding the risks associated with dental amalgam requires looking at the form of mercury involved, how much is released and how the body is exposed to it.

What Type of Mercury Is Used in Dental Fillings?

Amalgam contains elemental mercury, which reacts with other metals to form the hardened filling material.

This is different from methylmercury, the organic form of mercury associated with contamination in certain fish and seafood.

The different forms of mercury behave differently in the body and have different exposure pathways and health risks.

Although mercury is incorporated into the set filling, it isn’t correct to say that it becomes completely inert or that no mercury can ever be released.

Do Amalgam Fillings Release Mercury?

Yes. Dental amalgam can release small amounts of mercury vapour, which may be inhaled and absorbed through the lungs.

The amount released can vary depending on factors such as the number and condition of fillings and activities that place friction or pressure on their surfaces, including chewing and teeth grinding.

Mercury exposure can also temporarily increase when an amalgam filling is placed or removed.

However, detecting small amounts of mercury exposure doesn’t automatically mean that a person is experiencing mercury poisoning or damage to their health.

According to the US Food and Drug Administration (FDA), the available evidence does not show that mercury exposure from dental amalgam leads to adverse health effects in the general population, although uncertainties remain for some more susceptible groups.

Can Amalgam Fillings Cause Mercury Poisoning?

One of the biggest concerns patients have is whether mercury from old fillings could gradually build up in the body and cause illness.

Mercury exposure from amalgam can contribute to the mercury levels measured in the body, particularly in people with several fillings. However, studies have not demonstrated that this exposure causes mercury poisoning or clinically detectable organ damage in the general population.

That distinction matters. Mercury is genuinely hazardous at sufficiently high exposure levels, but it would be misleading to treat a properly functioning dental filling as equivalent to significant industrial mercury exposure.

Can Amalgam Fillings Cause Neurological Problems?

Over the years, amalgam fillings have been investigated in relation to a range of neurological and other long-term health conditions.

Although mercury can affect the nervous system at high exposure levels, the available clinical evidence has not established a causal relationship between dental amalgam fillings and neurological disease in the general population.

People sometimes attribute symptoms such as headaches, tiredness, memory problems or difficulty concentrating to their fillings. However, these symptoms can have many causes, and having an amalgam filling doesn’t establish that mercury is responsible.

If you’re experiencing persistent or unexplained symptoms, it’s important to speak to your GP rather than assume that removing dental fillings will resolve them.

What About People With Kidney or Neurological Conditions?

Some people may be more susceptible to the potential effects of mercury exposure.

For example, the FDA recommends additional caution when considering new amalgam fillings for people with impaired kidney function or certain pre-existing neurological conditions.

This doesn’t mean that everyone with one of these conditions needs their existing amalgam removed. Instead, it highlights the importance of an individual assessment involving the dentist and, where appropriate, the patient’s doctor.

Are Amalgam Fillings Safe During Pregnancy?

Pregnancy is one of the situations where specific restrictions apply to the use of dental amalgam in the UK.

Since July 2018, amalgam should not normally be used to treat:

• Pregnant women
• Breastfeeding women
• Children under 15 years old
• Deciduous (baby) teeth

An exception exists where a dentist considers amalgam strictly necessary because of the patient’s specific medical needs.

These restrictions are precautionary and reflect the intention to minimise avoidable mercury exposure, particularly during periods of development.

Should You Remove Existing Amalgam Fillings If You’re Pregnant?

Generally, no. If an existing amalgam filling is intact and there is no decay or other dental problem, routine removal simply because you’re pregnant isn’t recommended.

Removing a filling can temporarily increase mercury vapour exposure, and the procedure may also involve removing some healthy tooth structure.

If your filling is cracked, painful or otherwise requires treatment, your dentist can assess the situation and recommend an appropriate approach.

Pregnancy shouldn’t be a reason to leave a painful or infected tooth untreated. Necessary dental treatment can be planned with suitable precautions and materials.

Are Amalgam Fillings Banned in the UK?

There has been considerable confusion about this, particularly following changes to European legislation and international agreements on mercury.

As of October 2026, dental amalgam has not been subject to a blanket ban across the UK. Its use is restricted, and policy is moving towards phasing it out, but it can still be used in certain clinically appropriate circumstances.

Why Is Amalgam Being Phased Out?

A major reason is environmental protection.

Mercury can pollute the environment if it isn’t properly controlled throughout its production, use and disposal.

Dental amalgam contributes to mercury-containing waste, and dental practices must take precautions to prevent amalgam waste from entering the environment.

The Minamata Convention on Mercury is an international agreement aimed at reducing mercury pollution and its effects on human health and ecosystems.

Importantly, the environmental case for reducing amalgam use is not the same as evidence that existing fillings are causing harm to the people who have them.

What Changed in 2025?

The European Union introduced broad restrictions on the use of new dental amalgam from January 2025, subject to limited exemptions and transitional arrangements.

However, EU legislation does not automatically apply in the same way throughout the United Kingdom.

In November 2025, countries participating in the Minamata Convention agreed on a global phase-out of dental amalgam by 2034, with provisions for particular clinical needs.

The UK government subsequently confirmed that it was planning the steps needed to implement the transition towards the 2034 target.

For UK patients, the important point is that the move away from amalgam does not mean that existing silver fillings must be removed.

The focus is on reducing future use, encouraging effective alternatives and managing mercury-containing materials responsibly.

Should I Have My Amalgam Fillings Removed?

Not necessarily. In fact, if your fillings are in good condition, replacing them solely because they contain mercury may offer no proven health benefit.

Both the FDA and UK health guidance advise against unnecessary removal of otherwise sound amalgam fillings.

There are several reasons for this.

1. Removing a Filling Can Remove Healthy Tooth Structure

A filling doesn’t simply lift out of a tooth without any preparation.

The dentist needs to remove the existing material while protecting the surrounding enamel and dentine. Even with careful techniques, some healthy tooth structure may be lost.

Repeatedly replacing restorations can gradually make the remaining natural tooth smaller and more heavily restored.

For a tooth with a large filling, this may eventually make a crown or other indirect restoration necessary.

2. Mercury Exposure Can Temporarily Increase During Removal

Cutting and removing amalgam can produce mercury-containing particles and vapour.

Dental professionals use appropriate techniques, equipment and waste-management procedures to reduce exposure during treatment.

Nevertheless, removing a filling unnecessarily creates an exposure that may otherwise have been avoided.

3. Every Dental Procedure Has Some Risk

Replacing an old filling may lead to temporary sensitivity, discomfort when biting or, occasionally, irritation of the nerve inside the tooth.

If the original filling is particularly deep, the new restoration may be close to the pulp, increasing the possibility of further treatment.

This doesn’t mean amalgam fillings should never be replaced. It means there should be a sensible reason for undertaking the procedure and a discussion about the benefits and risks.

When Should an Old Amalgam Filling Be Replaced?

There are several situations where replacing an amalgam filling may be appropriate.

The Filling Is Cracked or Broken

If a filling fractures or part of it breaks away, the tooth may become vulnerable to further damage or decay.

Depending on the location and extent of the problem, the dentist may recommend repairing or replacing the restoration.

There Is Decay Around or Underneath the Filling

Natural teeth can develop new decay at the edges of an existing filling.

This is known as secondary or recurrent caries and can affect both amalgam and composite restorations.

If decay is present, treatment may be needed to remove the affected tooth structure and restore the area.

The Tooth Has Become Weakened

A large, old filling may occupy a substantial proportion of the tooth, leaving relatively thin natural walls around it.

Over time, these areas can become vulnerable to cracking or fracture, particularly in patients who grind their teeth or have a heavy bite.

If the tooth is structurally weakened, a dentist might recommend an inlay or onlay or, for more extensively damaged teeth, a dental crown.

You Have a Confirmed Allergy or Sensitivity

Although uncommon, some patients may experience an allergic or hypersensitivity reaction to a component of dental amalgam.

Possible local reactions can include certain changes to the tissues inside the mouth close to the restoration.

If an allergy is suspected, your dentist may recommend further assessment before deciding whether replacement is appropriate.

You Want a More Natural-Looking Smile

Some patients simply dislike the appearance of dark metal fillings, especially if they are visible when laughing or speaking.

Replacing amalgam with a tooth-coloured material may be an option for cosmetic reasons, provided the tooth is suitable and you understand the implications of removing an existing restoration.

At Glow Dental, we provide tooth-coloured composite fillings and can assess whether an existing metal restoration can be replaced with a more discreet alternative.

Amalgam Fillings vs White Fillings: Which Is Better?

Modern dentistry offers several alternatives to metal fillings. The most common is composite resin, generally known as a white filling.

Both amalgam and composite have advantages and limitations. Neither is automatically the best material for every tooth.

Appearance

This is where composite has a clear advantage.

Amalgam is metallic and usually darkens with age, making it more noticeable in visible areas of the mouth.

Composite is available in a range of tooth-coloured shades and can be matched to the natural teeth, producing a much less noticeable restoration.

Strength and Durability

Amalgam has a long clinical history and is particularly well known for its durability in back teeth subjected to substantial chewing forces.

Modern composite materials can also be strong and long-lasting, including in many back-tooth restorations.

However, the suitability and lifespan of either material depend on factors such as the size of the filling, the bite, the condition of the surrounding tooth and the quality of placement.

Large restorations may sometimes be better managed with an onlay or crown, regardless of whether the original filling was metal or composite.

Preserving Natural Tooth Structure

Composite bonds to the tooth using a dental adhesive system. In many cases, this allows the dentist to restore the damaged area while preserving more healthy tooth structure.

Traditional amalgam restorations generally rely on the physical shape of the prepared cavity to retain the filling.

However, when replacing an existing amalgam filling, the cavity is already present, so the amount of natural tooth that can be preserved depends on its current condition.

Placement Technique

Composite requires careful moisture control and bonding techniques to achieve a reliable restoration.

Amalgam is generally less sensitive to moisture during placement, which has historically made it useful in certain difficult clinical situations.

For this reason, the choice of filling material should consider the practical conditions in which the tooth needs to be restored.

Materials and Safety

Amalgam contains mercury, while conventional composite resin fillings do not.

Composite is widely used and generally well tolerated, but it isn’t entirely free from potential risks. For example, rare allergic reactions or sensitivities to certain resin components can occur.

Choosing a mercury-free material can be a perfectly reasonable patient preference, but it shouldn’t be based on the assumption that every existing amalgam filling is harmful.

So Which Should You Choose?

If you need a new filling and prefer a natural-looking, mercury-free restoration, composite may be a very suitable option.

However, if you already have a large amalgam filling that’s performing well, there may be no clinical advantage in replacing it immediately.

At Glow Dental, our approach is to assess the tooth and recommend a restoration that balances appearance, function and long-term preservation of the natural tooth.

For more information about composite restorations, read our article White Fillings for Front Teeth, which explains how modern tooth-coloured fillings work and what affects their durability.

How Are Amalgam Fillings Replaced With White Fillings?

If you and your dentist decide that replacing an amalgam filling is appropriate, the procedure is similar in some respects to replacing any old dental restoration.

However, additional care is needed when removing amalgam because it contains mercury.

Step 1: Examining the Tooth

The dentist first checks the condition of the existing filling, the surrounding tooth structure and your bite.

Dental X-rays may be taken where clinically necessary to look for decay or assess areas that are not visible during a routine examination.

It’s important to establish whether a direct composite filling will be suitable or whether a different type of restoration would provide a more predictable result.

Step 2: Removing the Existing Amalgam

The tooth is usually numbed with a local anaesthetic where necessary.

The dentist then carefully removes the existing filling using appropriate dental instruments, water cooling and suction to control debris and reduce exposure.

Isolation techniques may also be used according to the tooth and the procedure.

Dental amalgam waste must be collected and disposed of using appropriate procedures rather than allowed to enter ordinary wastewater or general waste.

Step 3: Checking the Remaining Tooth

Once the old restoration has been removed, the dentist can examine the underlying tooth more directly.

Any decay or damaged tooth structure is treated as necessary, while healthy tissue is preserved wherever possible.

If the tooth is more extensively damaged than expected, the planned restoration may need to change.

Step 4: Placing the New Restoration

For a suitable composite filling, the tooth is prepared using a dental bonding system.

The composite material is then placed, shaped and hardened with a curing light before being polished and adjusted to fit your bite.

The finished restoration can be matched closely to your natural tooth colour.

At Glow Dental, we use modern composite materials to restore damaged teeth and replace suitable old metal fillings with tooth-coloured restorations.

Patients who are also considering cosmetic improvements can learn more about our composite bonding treatments.

Is It Safe to Remove Several Amalgam Fillings at Once?

If you have multiple metal fillings, you might be tempted to have all of them replaced in a single appointment.

However, there isn’t a medical requirement to replace every amalgam filling simply because you have several.

Each tooth should be assessed individually.

Some fillings may be functioning perfectly well and need no treatment. Others might be approaching the end of their useful life or already showing signs of deterioration.

Where replacement is justified, your dentist can help plan the order and timing of treatment, taking account of tooth health, complexity, your preferences and any relevant medical circumstances.

Removing multiple healthy fillings without a clear benefit could mean unnecessary dental treatment and avoidable exposure during the removal procedures.

How Long Do Amalgam Fillings Last?

Amalgam is known for being a durable dental restorative material. Many fillings remain functional for well over a decade, and some last considerably longer.

However, there is no guarantee that an amalgam filling will last for a specific number of years.

Its longevity depends on several factors:

• The size of the original cavity
• The amount of natural tooth remaining
• Whether new decay develops around the restoration
• Teeth grinding or clenching
• The pressure placed on the tooth when chewing
• The quality and condition of the restoration
• Oral hygiene and regular dental care

An old filling doesn’t automatically need replacement because it has reached a particular age.

A dentist will consider how well it fits, whether there are signs of decay, whether the surrounding tooth is stable and whether the restoration is continuing to function correctly.

How Can You Tell If an Amalgam Filling Is Failing?

Sometimes a damaged filling causes obvious symptoms, but in other cases the problem is discovered during a routine dental examination.

Signs worth checking include:

• New sensitivity to hot, cold or sweet foods
• Pain when biting or chewing
• A piece of the filling breaking away
• A sharp or rough edge catching your tongue
• Food becoming repeatedly trapped around the filling
• A visible crack in the surrounding tooth
• A filling that feels loose or has changed shape
• Persistent toothache or swelling

These symptoms don’t necessarily mean the amalgam material itself is unsafe. They may indicate that the tooth or restoration needs assessment.

Regular dental examinations allow your dentist to monitor existing fillings and identify problems before they become more serious.

If you’re experiencing severe pain, a broken tooth or signs of infection, you may need an emergency dental appointment.

Frequently Asked Questions About Amalgam Fillings

Are Old Amalgam Fillings More Dangerous Than New Ones?

Not simply because they’re old. A filling that’s been in place for 20 or 30 years may still be functioning well. However, older restorations should be checked for wear, cracks, recurrent decay and deterioration of the surrounding tooth. Their condition matters more than their age alone.

Can Amalgam Fillings Cause Allergic Reactions?

Yes, but allergic and hypersensitivity reactions to amalgam components are uncommon. Some people may develop localised changes to the tissues inside the mouth near a restoration. If your dentist suspects a reaction, further assessment may be recommended before considering replacement.

Can You Have an MRI Scan With Amalgam Fillings?

In general, conventional dental amalgam fillings do not prevent patients from having routine clinical MRI scans. However, you should always follow the screening instructions provided by the radiology department and tell them about any dental restorations or other metalwork when asked.

Are White Fillings Safer Than Amalgam Fillings?

White composite fillings do not contain mercury and avoid mercury-related exposure and disposal concerns. They are widely used and generally considered safe. However, the available evidence also supports the safety of sound amalgam restorations for most people. Both materials have clinical advantages and limitations, and the most appropriate choice depends on the tooth and the patient.

Can Amalgam Fillings Cause Tooth Cracks?

Cracks can develop in teeth with large amalgam restorations, but that doesn’t mean amalgam always causes teeth to crack. Teeth weakened by extensive decay, large cavities, repeated chewing pressure or grinding may be more vulnerable to fractures. Your dentist can assess whether the surrounding tooth structure needs additional protection.

Is It Dangerous If a Small Piece of Amalgam Is Swallowed?

Accidentally swallowing a small fragment of amalgam is not generally associated with mercury poisoning. However, if a filling breaks, the tooth should be examined to check for exposed tissue, sharp edges or underlying decay. If you are choking, having difficulty breathing or believe a fragment has been inhaled, seek urgent medical attention.

Can Amalgam Fillings Be Replaced Just for Cosmetic Reasons?

Yes. Some patients choose to replace visible metal fillings because they prefer the appearance of tooth-coloured restorations. However, the decision should follow a dental assessment and discussion of the possible risks of removing a sound filling, including the potential loss of healthy tooth structure.

Do Amalgam Fillings Need to Be Replaced Before Teeth Whitening?

Not necessarily. Professional teeth whitening changes the colour of natural teeth but does not whiten amalgam or other filling materials. If a dark filling is visible and you would like a more uniform appearance, your dentist can discuss whether replacing it after whitening would be appropriate.

Do All NHS Dentists Still Use Amalgam Fillings?

No. The type of restoration offered depends on clinical need, the dentist’s assessment and the services available. Although amalgam can still be used in the UK in appropriate circumstances, tooth-coloured materials are increasingly common. NHS treatment availability and choices can differ from those offered privately.

Should I Be Worried If I Have Several Amalgam Fillings?

Having multiple amalgam fillings is not, by itself, evidence of a health problem. The amount of mercury exposure may vary with the number of fillings and other factors, but existing research has not established harmful health effects in the general population at the levels associated with dental amalgam. If you have specific medical concerns, discuss them with your dentist and GP.

Should You Keep Your Amalgam Fillings or Replace Them?

There’s no single answer that applies to everyone.

If your amalgam fillings are intact, your teeth are healthy and you’re comfortable with their appearance, there may be no good reason to disturb them.

On the other hand, if a filling is damaged, decay has developed around it or you’re unhappy with the appearance of visible metal restorations, replacement may be worth discussing.

The decision should be based on the condition of the tooth and the likely benefits of treatment, not simply on concerns raised by alarming headlines about mercury.

Modern tooth-coloured restorations can provide attractive, durable alternatives in many situations, but preserving healthy natural tooth structure should remain a priority.

Considering Replacing Metal Fillings? Visit Glow Dental in Battersea

If you have old silver fillings and aren’t sure whether they need attention, a dental examination is a good place to start.

At Glow Dental, we can assess your existing restorations, check for signs of deterioration or decay and explain whether leaving them in place, repairing them or replacing them would be most appropriate.

We provide natural-looking white composite fillings in Battersea, along with inlays, onlays and dental crowns for teeth that require more extensive restoration.

Our aim is to help you make an informed decision about your dental health while preserving as much of your natural tooth structure as possible.

If you’d like to discuss replacing an old metal filling, contact Glow Dental to arrange an appointment.

Glow Dental
87 Northcote Road
Battersea, London SW11 6PL
Telephone: 0207 223 7096

Sources and Further Reading

This article draws on information and guidance from the following organisations:

• British Dental Association – Using Dental Amalgam in the UK
• NHS – Dental Treatments
• NHS Business Services Authority – Can I Provide an Amalgam Filling?
• FDA – Dental Amalgam Fillings: Benefits, Risks and Recommendations
• UK Parliament – Government Response on the Dental Amalgam Phase-Out
• Minamata Convention on Mercury – Dental Amalgam

This article provides general information based on guidance available in October 2026. It does not replace an individual dental examination or advice from a qualified healthcare professional. Dental amalgam policy and regulations may change. Decisions about removing or replacing fillings should always be made following an assessment of your individual circumstances.