Dental health: Root canals

A root canal is a treatment used to repair and save a tooth that is badly decayed or becomes infected. During a root canal procedure, the nerve and pulp are removed and the inside of the tooth is cleaned and sealed. Without treatment, the tissue surrounding the tooth will become infected and abscesses may form.

"Root canal" is the term used to describe the natural cavity within the centre of the tooth. The pulp or pulp chamber is the soft area within the root canal. The tooth's nerve lies within the root canal.

A tooth's nerve is not vitally important to a tooth's health and function after the tooth has emerged through the gums. Its only function is sensory, to provide the sensation of hot or cold. The presence or absence of a nerve will not affect the day-to-day functioning of the tooth.

Why does the pulp need to be removed?

When nerve tissue or pulp is damaged, it breaks down and bacteria begin to multiply within the pulp chamber. The bacteria and other decayed debris can cause an infection or abscessed tooth. An abscess is a pus-filled pocket that forms at the end of the roots of the tooth. An abscess occurs when the infection spreads all the way past the ends of the roots of the tooth. In addition to an abscess, an infection in the root canal of a tooth can cause:

• Swelling that may spread to other areas of the face, neck, or head
• Bone loss around the tip of the root
• Drainage problems extending outward from the root. A hole can occur through the side of the tooth with drainage into the gums or through the cheek with drainage into the skin.

What damages a tooth's nerve and pulp in the first place?

Nerve and pulp can become irritated, inflamed and infected due to deep decay, repeated dental procedures on a tooth and/or large fillings, a crack or chip in the tooth, or trauma to the face.

What are the signs that a root canal is needed?

Sometimes no symptoms are present; however, signs to look for include:

• Severe toothachepain upon chewing or application of pressure
• Prolonged sensitivity/pain to heat or cold temperatures (after the hot or cold has been removed)
• Discolouration (a darkening) of the tooth
• Swelling and tenderness in the nearby gums
• A persistent or recurring pimple on the gums

What happens during the procedure?

A root canal requires one or more dentist surgery visits and can be performed by a dentist or endodontist. An endodontist is a dentist who specialises in the causes, diagnosis, prevention and treatment of diseases and injuries of the human dental pulp or the nerve of the tooth. The choice of which type of dentist to use depends to some degree on the difficulty of the root canal procedure needed in your particular tooth and the general dentist's comfort level in working on your tooth. Your dentist will discuss who might be best suited to perform the work in your particular case.