Fillings

Tooth fillings, also known as dental fillings, are used to replace natural tooth structure when it becomes fractured, broken or damaged by tooth decay. If you need a filling, your dentist can use a range of filling materials. Dental fillings will fix your tooth so it looks and works at its best.

Dental filling material options

When a dental filling is needed, there are different material options that your dentist can choose from to fix the tooth. Each dental filling material has advantages and disadvantages and there are different factors that can influence which one is used. Some factors include where the tooth is located in the mouth, how the teeth bite together, and how big or small the filling will be.

Your dentist will give you advice on dental filling options and what kind of dental filling is best for you. This could be different for each tooth.

Amalgam

Dental amalgam is a silver-coloured filling material. It is made of mercury, silver, copper, zinc and tin. It has been used as a filling material to fix teeth for over 150 years and has one of the longest life expectancies of dental filling materials. Dentists and scientists have done a lot of research on dental amalgam.

Amalgam was commonly used in dental fillings by dentists in the 1990s. These days it is less commonly used, with some dental practices choosing not to use it at all. Amalgam is strong and long-lasting, but more tooth structure needs to be cut away to fix the tooth with an amalgam filling. This is because the amalgam is held in place by the shape of the cavity that is cut into the tooth. Amalgam does not stick to the tooth surface like white filling materials do.

This filling material is silver in colour and can appear darker over time.

A dental amalgam filling in a molar tooth. Getty Images.

"Should I have my amalgam fillings removed?" is a commonly asked question. Read more about this here.

Composite resin

Composite resin is a tooth-coloured or white filling material. It can be used for fillings in both the front and back teeth. It is commonly used to fix broken or decayed teeth and for cosmetic dental treatments, such as veneers.

Composite fillings are glued to the surface of the tooth, which is called bonding. Because composite resin is bonded to the tooth’s surface, less tooth structure needs to be cut away for composite fillings to be placed. This means more natural tooth structure can be kept with composite resin fillings.

The colour of the material can be matched to the colour of the tooth being fixed. When the colour is well matched, the filling may not be able to be seen by other people looking at your teeth.

Before and after a composite resin filling in a molar tooth. Getty Images.

Left Cavity cut into the tooth after removing tooth decay. 

Right Cavity filled with a tooth-coloured composite resin filling.

This filling was completed using a rubber dam to isolate the tooth from the rest of the mouth.

Glass-ionomer cement

Glass-ionomer cement (GIC) is also a white or tooth-coloured filling material. It is not as strong as composite resin. Fluoride is an ingredient in this dental filling material. It has many uses, but common uses include fissure sealants and temporary fillings.

Gold and porcelain

Fillings can be made of gold and porcelain. Gold fillings and porcelain fillings are created outside of the mouth and then glued into the tooth’s cavity. This type of filling is called an inlay.

Gold and porcelain fillings are very strong and can last a long time. One advantage of a porcelain inlay is that they can be matched to the colour of the tooth. Both gold and porcelain fillings take time as they need to be made at a dental laboratory. It often takes at least two appointments.

Fissure sealants

Fissures are the grooves that are naturally present on the top, biting surface of the back teeth. These grooves can be very thin and deep. This can cause food and bacteria to become stuck.

When food and bacteria keep getting stuck over and over again, it can increase the risk of tooth decay developing inside the grooves.
A fissure sealant is a thin layer of dental filling material is placed over the grooves of the teeth. It is done to prevent food and bacteria from sticking in the grooves and to decrease the risk of tooth decay developing.

Fissure sealants are most commonly placed in the grooves of the back adult molar teeth in children and teenagers. Sometimes other teeth may also need fissure sealant treatment. The filling material is commonly white or clear. Sometimes the filling material will include fluoride for even more protection. Over time, using your teeth can cause the fissure sealant to wear down.

Fissure sealant in a back molar teeth. Getty Images.

Fissure sealants are not required in all children. Your dentist will let you know if this treatment is recommended for your childrens teeth.

Temporary fillings

In certain situations, temporary tooth fillings may be used. An example of when a temporary filling may be used is when the filling material will need to be removed again very soon or at your next dental appointment. Example situations where this may be done can include:

• when the same tooth needs to be treated a few times over multiple appointments,
• there is not enough time to complete treatment in one dental visit,
• during emergency dental treatment, or
• when covering up a tooth cavity between root canal treatment appointments.

After a filling

After a dental filling, the treated tooth may be sensitive to hot and or cold temperatures or when biting down. This is called post-operative sensitivity.

The sensitivity should go away after a few days. Sometimes, it can last 1 or 2 weeks. If the sensitivity does not go away or becomes worse where it causes pain, you should return to your dentist for them to investigate further.

How long will my filling last?

Fillings do not last forever. Fillings can become worn, chipped, cracked, or may change colour.

Over time, pressure applied to teeth can cause the join between the tooth and the filling to open. This can allow food particles and decay-causing bacteria to collect in this space. This may cause tooth decay. The amount of time a filling lasts can also depend on how well you look after it. It is important to brush your teeth twice daily and clean between your teeth every day as well.

Fillings can change colour. This means that a white dental filling may no longer match the colour of your natural tooth. This may be a concern for some people when it affects the front teeth. A dentist can replace the filling so it matches the colour of your natural tooth again.

Summary

Your dentist has many filling material options available to them. They will let you know the best filling material to fix your tooth.
Make sure to continue seeing your dentist for regular check-ups so that they can monitor your fillings. Your dentist can detect and treat any issues before they become more serious.

If you are due for a check-up but do not have a regular dentist, use the Australian Dental Association Find-A-Dentist search tool to find an ADA member dentist near you.