Tooth fillings

About tooth fillings

A dental filling is used to fill a cavity (a hole that has formed in your teeth) or other damage such as a chipped tooth.

Without treatment, a cavity or chipped tooth can lead to toothache, bad breath, infection, and even the fracturing or loss of your teeth.

Cavities get bigger over time, so the sooner they’re spotted and filled, the less likely you are to have problems later. That’s why regular check-ups are important.

The most common type of fillings are amalgam fillings. For more visible areas of the mouth, your dentist may recommend composite fillings, which more closely match the colour of your teeth.

Reasons for needing a tooth filling

Acid erosion

Your protective enamel coating can get worn away by acids in certain foods and drinks, or with some medical conditions like reflux or hiatus hernia.

Tooth decay

The most common reason for having a filling is tooth decay – where there is damage to the tooth structure. It occurs when plaque (the sticky-film of bacteria on teeth) uses the starch and sugars in food to make acid, which dissolves the enamel (the hard-protective coating on your teeth). This causes tiny holes in teeth, which then grow bigger.

Chipping

You might have a broken or chipped tooth as part of an injury, or after eating something very hard. This can expose the inner parts of the tooth and lead to erosion over time.

Worn-down teeth

Your teeth can become worn if you brush too aggressively or if you grind your teeth.

How do you know if you need a dental filling?

People of all ages, even young children, may need a tooth filling. You might have signs of tooth decay such as a nagging toothache, sudden pain when you bite down or sensitivity to hot and cold. You may even have noticed a cavity, or food getting caught in a damaged tooth.

If you have chipped or fractured your tooth it’s also important to see your dentist, who may recommend a filling.

What kind of fillings are available?

There are a range of fillings available. The type of treatment you need will depend on a range of factors, including the amount of damage and which tooth is affected. Your dentist will talk through the most suitable options with you before going ahead with any treatment:

Amalgam

These traditional silver-coloured fillings are made from a combination of metals including silver, tin and copper. Amalgam is very hard-wearing, so it’s ideal for fillings in your back teeth. The fillings can last for several years, as long you take good care of your teeth. If you’re pregnant, your dentist might advise against an amalgam filling, but they can discuss this with you. Amalgam fillings are available on the NHS and privately.

Composite

Also known as white fillings, composite fillings match the natural colour of your teeth and are more aesthetically pleasing than amalgam fillings. Composite fillings are made from a plastic glass mixture and are very durable; they often go completely unnoticed. They’re generally only available privately, unless your dentist thinks they’re clinically necessary.

Glass ionomer

Made of a powdered glass, these fillings are also tooth-coloured. They form a chemical bond with your tooth and can release fluoride, helping prevent further tooth decay. These fillings are slightly less durable than other types, so are typically used for temporary fillings, children’s ‘baby teeth’ or ‘non-biting’ surfaces, on the side walls of teeth.

Inlays and overlays

If a standard filling isn’t suitable, your dentist may recommend an inlay or overlay (sometimes called onlays, too). They’re more suitable for larger chewing surfaces, such as your back teeth. Inlays fit into the hole in your tooth, while overlays build up the shape of the tooth. They can be made from metal, composite or porcelain. Porcelain may be ideal if you're looking for something that's near-invisible.

If the tooth cavity is very deep, or the centre of your tooth is damaged, you may need root canal treatment to avoid having the tooth out. Although often called ‘root canal fillings’, these aren’t the same as a standard filling.

How are dental fillings placed?

Step 1

First of all, your dentist will numb the area to be treated, usually using local anaesthetic.

Step 2

To prepare the tooth for a filling, they’ll remove any decayed or weakened parts of the tooth, before shaping, cleaning and drying the remaining tooth.

Step 3

Once ready, they’ll fill the cavity with an amalgam or composite filling.

Step 4

Finally, your dentist will polish the filling to prevent staining and early wear and check your bite still feels right when you put your teeth together.

What should you do after you’ve had a filling?

If you have local anaesthetic, your gums, tongue, cheeks and even your lips will feel numb for a while. Until this wears off, you may have difficulty talking, chewing and drinking. As sensation returns, you may feel some tingling. Avoid chewing on that side for a while, partly to protect your filling but also to prevent accidentally biting yourself.

For up to a week after your filling, your tooth may be more sensitive to cold and heat. If it gets much worse or goes on for longer, tell your dentist – this could indicate changes to the nerve, which may need treatment.

How can you avoid fillings in the future?

Dental fillings are a very good way to repair tooth cavities, and they can stop toothache while preventing further tooth decay. But it’s much better to avoid tooth fillings in the first place. You can help to do this, by following dental advice:

• Reduce the frequency you consume sugary of acidic foods and drinks throughout the day. If you sip on a sugary drink throughout the day, for example, your teeth are exposed to the sugar for longer, and your mouth doesn’t have chance to recover. Learn more about how sugar affects teeth and how to combat its negative effects.
• See your dentist and dental hygienist regularly
• Clean between your teeth before brushing using floss or interdental brushes
• Brush your teeth twice a day for two minutes
• Use the right toothpaste and toothbrush; your dentist or dental hygienist can advise you on what’s best for you
• Change your toothbrush (or electric toothbrush head) at least once every three months

Your dentist is the best person to give you advice on how to look after your teeth.