Steps to a Filling
When you visit your dentist to get a filling, you will be given local anesthesia to numb the area if necessary. Next, your dentist will remove decay from the tooth, using hand instruments or a drill. Air abrasion and lasers also can be used to remove decay. A drill, which dentists call a handpiece, uses metal cones called burs to cut through the enamel and remove the decay. Burs come in many shapes and sizes. Your dentist will choose the ones that are right for the size and location of your decay.
At first, your dentist will use a high speed drill (the one with the familiar whining sound) to cut through the hard enamel. He or she will precisely outline the cavity with the drill, removing only enough of the tooth so the filling can be placed properly. Once the drill reaches the dentin, or second layer of the tooth, the dentist may use a lower speed drill. That's because dentin is softer than enamel.
Throughout the removal process, your dentist will test the area with the explorer to see if all the decay has been removed.
Once all the decay is removed, your dentist will shape the space to prepare it for the filling. Different types of fillings require different shaping procedures to make sure they will stay in place. Your dentist may put in a base or a liner to protect the tooth's pulp (where the nerves are). The base or liner can be made of composite resin, glass ionomer, zinc oxide and eugenol, or another material.
Some of these materials release fluoride to protect the tooth from further decay.
If your dentist is placing a bonded filling, he or she will etch (prepare) the tooth with an acid gel before placing the filling. Etching makes tiny holes in the tooth's enamel surface. This allows the filling to bond tightly to the tooth. Bonded fillings can reduce sensitivity. They also can reduce the risk of leakage or decay under the filling. That's because the etched surface of the tooth and the filling material form a mechanical bond. Bonding is generally done with composite fillings. It can also be done with amalgam.
Certain types of fillings get hardened by a special light. With these fillings, your dentist will stop several times to shine a bright blue light on the resin. This cures (hardens) the material and makes it strong.
Finally, after the filling is placed, your dentist will use burs to finish and polish the tooth.
Steps to a Filling