Root canal treatment involves the removal of the pulp tissues (the innermost part of the tooth where the nerve is found) from the tooth in the event that it gets infected or inflamed. The pulp can be infected or inflamed for many reasons, but usually because of deep decay, an extensive filling or trauma.
Root canal treatment saves teeth that would otherwise have been extracted. It involves removal of the infected or inflamed pulp using small, specially designed hand or rotary files and back filling each nerve canal with a filling material. The tooth may eventually need a crown depending on how much tooth tissue is left.