A dental filling or also known as pasta is a way to restore a tooth damaged by decay back to its normal function and shape. When a 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 prevent further decay. Materials used for fillings include gold, porcelain, a composite resin (tooth-colored fillings), and an amalgam (an alloy of mercury, silver, copper, tin and sometimes zinc).
Fillings are also used to repair cracked or broken teeth and teeth that have been worn down from misuse such as from nail-biting or tooth grinding. The dentist will tell you what type of restorative material will be used depending on the case of your tooth.