Dental decay – how to tell if you need a tooth filling

Dental decay is a serious issue. If left untreated, it can become a serious threat to your dental hygiene and cause you a lot of pain. Tooth fillings can be used to help solve this problem and help you achieve your perfect smile. Could you need a tooth filling? To help you find out, we’ve put together this guide on dental decay and tooth fillings.

What is dental decay?

Simply put, dental decay is the process of sugary food dissolving teeth.

Whenever sugars in the food we eat and drink react to the bacteria in plaque, it forms acids that soften and dissolve the enamel and dentine of a tooth. The acid is eventually neutralised through natural salts in your saliva but can attack your teeth for up to an hour after eating and drinking.

Over time, the sugary food will make a cavity (hole) in the tooth.
There are three types of cavities dental decay can cause:

1. Coronal cavities

This is the most common type and is located on chewing surfaces or between the teeth. This type of cavity is common in both children and adults.

2. Root cavities

Our gums recede as we age, which leaves parts of our tooth roots exposed. Since there is no enamel covering tooth roots, these exposed areas are more susceptible to dental decay.

3. Recurrent decay

This type of cavity is located around existing fillings and crowns which have accumulated a build-up of plaque.

Without treatment, dental decay can destroy your tooth and kill the delicate nerves at its centre. It can also cause the area at the root tip to become infected. Once this part is infected, it the tooth can only be treated with root canal, surgery or by extracting the tooth.

If the decay is not too serious, it can be removed. The tooth can then be restored with either a white or silver filling. The silver fillings contain mercury, while the white fillings are made from a durable white material that matches the colour of your teeth.

If caught early enough, sometimes dental decay can also be treated with a fluoride varnish to help stop more decay.

How to tell if you need a filling

Unfortunately, dental decay does not have a lot of symptoms in its early stages. However, if you experience any of the following symptoms, contact your dentist for a consultation.

1. Tooth sensitivity

Does one of your teeth feel sensitive when exposed to certain foods, such as hot or cold temperatures, or sweet, sticky and sour foods?

2. Flossing string tears

When you floss, does the string tear each time you floss a particular tooth?

3. Damage to a previous filling

If a previous filling is cracked, broken or missing, you may need to replace the filling.

4. A chipped or fractured tooth

Is your tooth damaged?

5. Food stuck between teeth

When you eat, does your food always get stuck on or between certain teeth?

6. Dark spots

Can you see or feel a dark spot or a hole in your tooth? Does your tooth feel rough?

7. Throbbing or sharp pain

Do you have throbbing in your mouth, or pain in your tooth when you bite down or chew your food?

It’s important to understand that even if you don’t have any of these signs or symptoms, you can still be at risk of dental decay.


Dental decay dissolves your teeth, creating cavities. If left untreated, it can lead to serious dental hygiene problems, infections and may even require surgery to fix. Tooth fillings are used to treat dental decay in common cases, but your dentist will be able to tell you if you need fillings or not.

Dental decay spreads fast, so if you have any signs or symptoms contact your dentist as soon as possible. Unfortunately, dental decay doesn’t always have symptoms until it’s too late, so it’s important that you go for regular check-ups.

Ready to achieve your perfect smile? Book a consultation today.