Root canal treatment is used to save a tooth when the dental pulp (blood vessels and nerve in the centre of the tooth) dies and the tooth becomes infected.

The cause of infection is usually decay in the tooth, under a filling or due to the fracture of a tooth. Without treatment, this can cause a dental abscess resulting in pain, swelling and infection of the jaw bone. 

When a tooth nerve has died, the only alternative to carrying out root canal treatment is to remove the tooth. The aim of root canal therapy is to avoid removal of the tooth where possible.