About Your Tooth
Your teeth are composed of four dental tissues. Three of them—enamel, dentin and cementum—are hard tissues. The fourth tissue—pulp, or the center of the tooth that contains nerves, blood vessels and connective tissue—is a soft, or non-calcified, tissue. Your tooth consists of two main parts: the crown, which is that part of the tooth above the gum and visible in your mouth; and the root or roots, which is that part of the tooth that lies beneath the gum and is surrounded by bone. Inside each root is a channel that runs the length of the tooth. This channel is the root canal and contains the pulp (nerves, blood vessels, and soft tissue), which is often referred to as the “nerve” of the tooth. The pulp may be irreversibly damaged by bacteria associated with decay, very deep restorations, fractures, trauma, or periodontal disease.
In order to preserve a tooth in which this has occurred, it is necessary to remove the diseased pulp tissue. This procedure is known as endodontic therapy. Since endodontic therapy is concerned with removing only the pulp from the root canal, the root will continue to function normally because the supporting tissues remain intact. It is advisable to remove the injured pulp because it may become infected, or act as an irritant to the tissues surrounding the tooth.