All teeth contain nerves (pulp) which supplies the tooth with hot, cold and pain sensation. The nerve can be damaged by decay, trauma, wear or by large fillings. When this occurs the nerve can become inflamed and die. The infection can spread from the nerve into the surrounding bone leading to pain and swelling.
A root canal treatment involves the removal of the damage nerve with small files to create a sterile bacteria free environment, which is then filled with a biocompatible material. The root canal filling is contained within the root only.
Once a root canal treatment has been completed the tooth will require provision of a filling or crown to effectively seal the root filling.