Tooth decay (also known as dental caries or cavities) is the most common chronic dental disease that affects individuals of all ages, posing significant risks to oral health and overall well-being. Untreated cavities can lead to various systemic conditions, including cardiovascular diseases, kidney disease, joint inflammation and diabetes.

What is tooth decay?

Tooth decay is a common diet-related dental disease that leads to the loss of hard minerals from adult and baby teeth. In its early stages it can appear as a white or yellow spot on the tooth, but as more minerals are lost, a cavity or hole may appear. Further mineral loss may lead to the cavity going into the center of the tooth (the pulp). Untreated tooth decay can lead to many uncomfortable physical consequences, including: pain and discomfort, headache, increased sensitivity, infection or abscesses, gum disease and even tooth loss. These physical symptoms can negatively impact life and cause problems.

What causes tooth decay?

Tooth decay happens when bacteria in the mouth break down enamel and dentin. A combination of factors can cause tooth decay, including poor hygiene and a diet rich in sugar.

Poor oral hygiene allows bacteria to build up on the teeth, leading to plaque formation. Plaque is a sticky film containing bacteria that can cause tooth decay if not removed regularly. Sugary, sticky and acidic foods and drinks are a major cause of tooth decay. All sugars and most cooked starchy foods are major plaque promoters, including milk, honey, jam, raisins, sweets, cereal and also bread. Dental caries develop when these foods and drinks are consumed frequently, as the bacteria in the mouth feed on sugars and acids. These acids break down the enamel and dentin of the teeth. On the other hand, acidic foods and drinks can wear down and weaken enamel. Over time, this will make your teeth more sensitive and cause enamel erosion.

The more sugar you eat, the more acid gets produced leading to decay. Sugar combines with a plaque to weaken the enamel leaving you vulnerable to tooth decay. Each time you have a sugary snack or drink, your teeth are vulnerable to damage from the acids for the next 30 minutes. It is therefore very important to brush your teeth after every meal.

How is tooth decay treated?

If the decay is not too serious, the dentist will remove all the decay and repair the tooth with a filling. Sometimes the nerve in the middle of the tooth can be damaged. If so, the dentist will need to carry out root canal treatment by removing the nerve and then repairing the tooth with a filling or a crown. If the tooth is so badly decayed that it cannot be repaired, the dentist may have no choice but to take the tooth out.

How to prevent tooth decay

You can help prevent tooth decay by following these tips:

  • practice good oral hygiene – brush your teeth after every meal with a fluoride toothpaste and clean between your teeth daily with floss or interdental brush
  • eat nutritious and balanced foods and limit snacking in-between meals
  • avoid sugary food and drinks – they are the main cause of tooth decay
  • drink lots of water – it will help flush out food stuck in your mouth
  • visit your dentist regularly for professional cleanings and examination


Tooth decay is a common dental issue that can be prevented and reversed if caught in the earliest stages. To prevent tooth decay, it’s important to maintain good oral hygiene. As mentioned above, see a dentist immediately if you experience any concerning symptoms.