A filling 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.

If the damage hasn't affected the pulp, the filling, using a polymer material (resin), covers the lost part of the tooth, and so the normal function and the aesthetics of the tooth are replaced.

Resins are the most commonly used material for fillings.