How do teeth decay?

• Germs (bacteria) in our mouth grow on teeth every day. They form a sticky layer over the teeth called dental plaque. The bacteria in plaque use sugars in the things we drink and eat, and make acids. The acid attacks the tooth’s outer layers (enamel and dentine) and eats them away.
• If acid continues to attack, then a hole will appear in the tooth’s outer layer. This is called tooth decay (or dental caries). Tooth decay may be painful or you may not even know it is there.
• Saliva neutralises the acid in plaque. If the plaque is brushed off and saliva surrounds the tooth, the enamel surface can harden again. Fluoride helps the enamel to be repaired.
  If the tooth continues to decay, a number of things could happen:

The tooth could break.

• The nerve or pulp could get infected and the nerve could die.
• You could have a toothache.
• You could get facial swelling.
• You might feel sick.
• You might need a filling.
• The tooth might need to be taken out (this does not need to happen often now).