If cavities progress deep enough into the tooth, to involve the pulp tissue of the tooth, a root canal is sometimes neccessary to fix the tooth. Aoot root canal cleans out the infection in the pulp tissue, allowing us to fix and keep the tooth.
The tooth is made up of three different materials or sections. The white, hard, outer layer is the enamel. Under the enamel is a softer and porous material called dentin. Deep within the body of the tooth, under the dentin is what we call the pulp of the tooth. The pulp of the tooth is made up of the blood supply and the nerve supply of the tooth. Our teeth are alive and vital structures. The pulp of the tooth is what allows the tooth to be alive and vital and respond to stimuli, such as hot and cold. Cavities are caused by a special type of bacteria that are always present in our mouths. When these cavity causing bacteria progress and grow uncheck in our teeths, they enter the pulp and a bacterial infection occurs in the blood supply of our tooth. We fix this infection with a procedure called a root canal.
Why is the procedure called a root canal? Good question. Well, the upper portion of our teeth, the part that we see in our mouth and the part of the tooth that we use to chew with, is anchored into our jaw bones by extentions called roots. The roots extend from the main portion of the tooth into the bone. The main portion of the pulp of our tooth (called the pulp chamber) is housed within the main portion of our tooth. The pulp chmaber has off shoots that extend down the middle of the roots. The off shoots of the pulp are called pulp canals. The bacterial infection encompasses the pulp chamber and also the pulp canals. During a root canal procedure, we disinfect the pulp chamber and canals all the way to the end of the tooths roots. That's why it's called a root canal!