What exactly are silver fillings?

The term “silver fillings” is a little misleading. In dentistry, this material is known as dental amalgam, and while it looks silver, it’s actually a blend of metals. A typical amalgam is roughly half elemental mercury, combined with a powdered alloy of silver, tin and copper.

Amalgam has been used for over 150 years, and for good reason. It’s inexpensive, relatively straightforward to place, and extremely hard-wearing. Once mixed, the metals form a durable putty that packs neatly into a cleaned-out cavity and sets quickly, standing up to years of chewing and grinding.

So, do dentists still use silver fillings today?

The short answer is yes, but far less often than they used to. Amalgam is still legally available and taught in dental schools, but for most modern, cosmetically-minded practices it’s no longer the first choice. The clear trend across UK dentistry is a steady move towards tooth-coloured materials that look more natural and preserve more of your healthy tooth.

There are still occasional clinical situations where amalgam has practical strengths, particularly for very large cavities in back molars, where the bite forces are highest and keeping the area perfectly dry (a requirement for white fillings) can be difficult. But these are increasingly the exception rather than the rule. All-ceramic onlays or inlays are the go-to restorative material in these situations now.

What do UK guidelines say about amalgam?

In the UK, the use of dental amalgam is being formally phased down, mainly for environmental reasons rather than concerns about patient safety. This follows the global Minamata Convention on Mercury, which the UK has signed up to.

Since 1 July 2018, regulations have restricted new amalgam fillings in certain groups unless a dentist judges it strictly necessary for that person’s specific dental or medical needs. Those groups are:

• Children under 15 years old
• Pregnant women
• Breastfeeding women
• Anyone needing a filling in a baby (primary) tooth

It’s worth being reassured on one point: these rules apply to placing new fillings. Current UK and European expert guidance is clear that there’s no need to remove existing, healthy amalgam fillings as a precaution. The only routine exception is a patient with a diagnosed allergy to one of amalgam’s components. If your old fillings are sound, the advice is generally to leave them be.

Are silver fillings bad for you?

Because amalgam contains mercury, it’s completely understandable that patients ask us whether silver fillings are safe. Mercury is a naturally occurring element, but at high levels of exposure it can be toxic, and tiny amounts of mercury vapour can be released from a filling when you chew firmly, grind your teeth or drink something hot.

The reassuring news is that, based on current scientific evidence, major health bodies, including the European Commission’s Scientific Committee on Emerging and Newly Identified Health Risks (SCENIHR), have concluded that neither amalgam nor its alternatives are harmful to the health of the general population. It has been linked to lichen planus (a non-infectious inflammatory condition that causes itchy rashes on the skin and painful white or red patches in mucous membranes) and commonly recommended by oral medicine specialists to remove them as first line treatment. The amount of vapour involved is very small, often less than you’d be exposed to from eating certain types of seafood.  

As noted above, current guidance still takes a precautionary approach for children under 15 and for pregnant or breastfeeding women, recommending alternatives where possible. This is an environmental and precautionary position rather than evidence that amalgam causes harm in these groups. If you have any concerns about your own fillings, we’re always happy to talk them through with you honestly at a consultation.

Silver fillings versus white fillings: which is better?

When you compare silver and white (composite) fillings, the differences go well beyond colour. Like most modern practices, we use tooth-coloured composite resins for the vast majority of fillings, and here’s why our patients tend to prefer them.

Appearance. Composite can be custom-blended to match the exact shade of your natural tooth, so the filling is virtually invisible. Amalgam is dark and opaque, and over time it can stain the surrounding tooth a greyish hue.

Preserving your natural tooth. Placing amalgam usually means cutting a wedge-shaped “undercut” into a healthy tooth so the metal locks in place. Composite, by contrast, bonds chemically to the tooth, which lets us be far more conservative and keep as much of your natural enamel as possible. That conservative, tooth-preserving philosophy is at the heart of how we work.

A metal-free option. For patients who simply prefer to avoid metals, composite resins, glass ionomers and ceramics contain no mercury, which many people find reassuring.

Cost and the NHS picture. Composite fillings are generally more expensive than amalgam, and on the NHS white fillings are typically only provided for front teeth. If you’d like a tooth-coloured filling on a back tooth, that’s usually a private option, something we’re always upfront about before any treatment begins.

What about your existing silver fillings?

Like many adults, you may already have a few metal fillings from childhood. Amalgam is tough and can last anywhere from 10 to 15 years, sometimes much longer, but no filling lasts forever. Over time, chewing and the natural acidity of your mouth take their toll.

It’s worth keeping an eye out for signs that an older filling may be failing:

• Sensitivity to hot, cold or sweet foods
• A sharp or rough edge you can feel with your tongue
• Visible gaps between the metal and the tooth
• A dull ache when biting down on something hard
• General greying of the tooth itself which suggests the margins are no longer sealed and it's leaking

One genuine long-term consideration with larger, ageing amalgam fillings is the risk of cracks. Metal expands and contracts with temperature differently to natural enamel, so every hot coffee or cold dessert puts a little stress on the surrounding tooth. Over many years this can lead to hairline fractures, and occasionally a tooth can split, which may then need a crown or, in some cases, removal. If you’re ever unsure about an old filling, it’s well worth having it checked.

A careful approach to replacing old fillings

If a filling is genuinely failing, or you’d like to replace it for cosmetic reasons, it’s important to know that drilling out amalgam releases more mercury vapour than simply leaving it in place. That’s why, when removal is the right choice, it should be done carefully and with appropriate safety measures, such as:

• A rubber dam to isolate the tooth and stop you swallowing any fragments
• High-volume suction to capture vapour and particles
• Plenty of water to keep the filling cool and minimise vapour
• Careful technique to protect both you and the surrounding tooth

Our preference, always, is to recommend removal only when there’s a sound clinical or genuine cosmetic reason, never just for the sake of it.

Why patients choose Siha Dental for fillings in West London

At our Shepherd’s Bush practice, our philosophy is to protect and enhance your natural smile with as little intervention as possible. When you need a filling, that means using tooth-coloured materials that look natural and conserve as much of your healthy tooth as we can. Patients from Shepherd’s Bush, Hammersmith, Acton, Chiswick and across West London choose us because we offer:

• A holistic, prevention-led approach to your oral health and overall wellbeing
• Honest, transparent treatment planning to cater for all needs
• Natural-looking, tooth-coloured fillings placed conservatively to preserve your enamel
• A calm, spa-inspired environment designed to put even nervous patients at ease
• Award winning patient care in London for 2024 and 2025 - don’t just take our word for it! ~ View our awards here

Frequently asked questions about silver fillings

Do I need to have my old silver fillings removed?

Not usually. If your existing fillings are healthy and intact, current UK guidance is to leave them in place rather than remove them as a precaution. We’ll only ever recommend replacing a filling if there’s a clear clinical reason, such as decay, cracking or a failing edge, or if you’d like to update it cosmetically.

Are white fillings as strong as silver ones?

Modern composite materials are very durable and perform extremely well for the vast majority of fillings. Amalgam can still have an edge for very large cavities in back teeth under heavy bite forces, which is something we’ll always assess on a case-by-case basis and discuss with you.

Can I have my silver fillings replaced with white ones?

Yes. Many patients choose to update older metal fillings to natural-looking composite, either for appearance or peace of mind. We’ll carry out the removal carefully, with the appropriate safety measures, and match the new filling to your natural tooth shade.

Are amalgam fillings safe during pregnancy?

Current guidance recommends avoiding new amalgam fillings during pregnancy and breastfeeding as a precaution, and we’d use a tooth-coloured alternative instead. There’s no advice to remove existing healthy fillings while pregnant. If you’re expecting, just let us know so we can tailor your care accordingly.

Will my insurance or the NHS cover white fillings?

On the NHS, white fillings are normally provided for front teeth, while back teeth are often filled with amalgam. If you’d prefer a tooth-coloured filling on a back tooth, this is usually available privately, and we’ll always explain your options and any costs clearly before we begin.

Thinking about your fillings? Book a consultation

Whether you’ve got a new cavity to treat or you’re thinking about updating older metal fillings, we’d be glad to talk you through the most conservative, natural-looking options for your smile. At Siha Dental in Shepherd’s Bush, we’ll assess your teeth honestly and recommend only what’s genuinely right for you. Book a consultation at Siha Dental today, or call us on 020 4602 3510.