As part of your dental exam, your dentist will check any existing fillings and may suggest that you replace any loose or broken ones.  Your dentist will also look for signs of decay and may want to use x-rays to determine if any identified problem spots need treatment.  Typically your dentist will suggest that cavities be filled right away to prevent the tooth from having to be removed later.

Filings are a way to restore a tooth damaged by decay.  This restores the tooth back to its normal function and shape.  When your dentist gives you a filling, they must first remove the decayed material, clean the affect area adn then fill the cavity with a filling material.  This effectively closes the spaces where bacteria can enter the tooth, preventing further decay and infection.

The most common material used in fillings is Amalgam (silver) fillings or composite (plastic) resins.  Amalgam fillings are resistent to wear and are relatively inexpensive.  However, their dark colour makes them more noticeable in your mouth.  Composite resins are matched to the same colour as your teeth and present a more natural appearance.

If your dentist is suggesting a filling, they will first remove the decay and clean the affected area.  This is typically done with a dental drill, requiring the dentist to give you a local anestic to prevent pain and discomfort during the procedure.  Once the cavity is cleaned, it is then filled with an appropriate material and hardened with a special light.