A filling is a way to restore a tooth damaged by decay back to its normal function and shape. When your dentist gives you a filling, he or she first removes the decayed tooth material, cleans the affected area, and then fills the cleaned out cavity with a filling material. By closing off spaces where bacteria can enter, a filling also helps to prevent further decay. The most commonly used materials for filling include:

• Composite resin (tooth-coloured fillings)
• Amalgam (an alloy of mercury, silver, copper, tin and sometimes zinc)