To treat a cavity your dentist will remove the decayed portion of the tooth and then fill the area on the tooth where the decayed material was removed.
Fillings are also used to repair cracked or broken teeth and teeth that have been worn down from misuse from nail-biting or tooth-grinding. The dentist will use a local anesthetic to numb the area around the tooth to be filled. Next, a drill, air abrasion instrument or laser will be used to remove the decayed area. Your dentist will probe the area to determine if all the decay has been removed and then will prepare the space for the filling by cleaning the cavity of bacteria and debris. If the decay is near the root, your dentist may first put in a liner made of glass ionomer, composite resin, or other material to protect the nerve. Generally, after the filling is in, your dentist will finish and polish it. The tooth-colored material is applied in layers and a special light that "cures" or hardens each layer is applied. When the multilayering process is completed, the dentist will shape the composite material to the desired result, trim off any excess material, and polish the final restoration.
Teeth can be filled with porcelain, gold, silver amalgam (which consists of mercury mixed with silver, zinc, tin, and copper) or tooth-colored, plastic, and materials called composite resin fillings. There is also a material that contains glass particles and is known as glass ionomer. This material is used in ways similar to the use of composite resin fillings.