Root Canal is the commonly used term for the main canals within the dentin of the tooth. These are part of the natural cavity within a tooth that consists of the dental pulp chamber, the main canals, and sometimes more intricate anatomical branches that may connect the root canals to each other or to the root surface of the tooth. Root canals are filled with a highly vascularized, loose connective tissue, the dental pulp. This sometimes becomes infected and inflamed, generally due to caries or tooth fractures that allow microorganisms, mostly bacteria from the oral flora or their byproducts, access to the pulp chamber or the root canals; the infected tissue is removed by a surgical intervention known as endodontic therapy and commonly called a root canal.

At the center of a tooth is a hollow area that houses soft tissue, known as pulp. This hollow area contains a relatively wide space towards the chewing surface of the tooth called the pulp chamber. This chamber is connected to the tip of the root of the tooth via thin hollow pipe-like canals-hence, the term “root canal”. Human teeth normally have one to four canals, with teeth toward the back of the mouth having the most. These canals run through the center of the roots like pencil lead runs through the length of a pencil. The tooth receives nutrition through the blood vessels and nerves traversing these canals.