A tooth has between one and three roots, of which could each contain up to four canals, which contain the nerves, blood and lymph vessels (also known as the pulp).
When the pulp becomes infected, usually from a deep cavity or fracture that allows bacteria to creep in, or injury due to trauma, it can die. Damaged or dead pulp causes increased blood flow and cellular activity, and pressure cannot be relieved from inside the tooth. Pain in the tooth is commonly felt when biting down, chewing on it and applying hot or cold foods and drinks.
Root canal therapy is performed in order to save the tooth. The procedure involves cleaning out the diseased pulp (canal), placing a biocompatible material in that canal, and permanently sealing the tooth. Typically a crown is used to restore the tooth to its original shape and function.
In most cases, a root canal is a relatively simple procedure with little or no discomfort involving one to three visits. Having a root canal preformed on a tooth is the treatment of choice to save a tooth that otherwise would have to be removed. Many patients believe that removing a tooth that is problematic is the solution, but what is not realized is that extracting (pulling) a tooth will ultimately be more costly and cause significant problems for the adjacent teeth.
After treatment, your tooth may still be sensitive, but this will subside as the inflammation diminishes and the tooth has healed.
Root canals are a treatment that can be very successful and can restore a tooth that otherwise would be lost. In rare cases the tooth will have to be retreated due to recurring infection.