Dental decay

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Information for the public about tooth decay.

The information comprises:

  1. Introduction
  2. Causes of tooth decay
  3. Treating tooth decay
  4. Preventing tooth decay


Tooth decay, also known as dental decay or dental caries, is when acids in your mouth dissolve the outer layers of your teeth.

Why it occurs

Your mouth is full of bacteria, which combine with small food particles and saliva to form a sticky film known as plaque that builds up on your teeth.

When you consume food and drink that is high in carbohydrates (sugary or starchy), the bacteria in plaque turn the carbohydrates into the energy they need, producing acid at the same time.

Over time, the acid in plaque begins to break down the surface of your tooth. Left untreated, the plaque can completely destroy the outside of the tooth, exposing the nerves inside. Once this happens, you will experience toothache and with no treatment the tooth will eventually fall out.

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