What is root canal therapy and why do I need it?

root canal

When dental decay is deep, it can cause inflammation of the nerve (pulp) inside the tooth. Bacteria can also invade the nerve, causing an infection. When this happens, possible signs and symptoms include pain in response to heat and pressure; intraoral abscess; and/or facial swelling.

Nerve infection can also occur after an impact has caused a tooth to be broken and the nerve to be exposed, or the trauma might cause displacement of the tooth from its normal position, severing the tooth’s blood supply.

In all such instances, two main treatment options are available to alleviate pain and eradicate infection:

  • removing the tooth
  • treating the root canal.

The advantage of root canal treatment, also known as root canal therapy, is that your tooth will be saved. However, this treatment is not feasible if there is insufficient healthy tooth structure remaining.

What does root canal treatment involve?

There are several stages in the treatment process and these are usually spread over two or three appointments. During each appointment it is common for at least one X-ray of the tooth to be taken.

Before treatment, some local anaesthetic is administered to the area to make it completely numb, and the tooth is surrounded by a rubber sheet known as a dam. This isolates the tooth from the bacteria and saliva in the rest of your mouth.

Then all decay, along with the inflamed / infected nerve, is removed from the tooth. The tooth is flushed out, or irrigated, and sometimes a medicine is placed inside it and remains for several weeks to help reduce inflammation, with a temporary filling holding it in place.

After root canal therapy, it is important for the tooth to be properly sealed so as to prevent leakage and a re-invasion of bacteria. A permanent filling is therefore placed where the nerve used to be. This filling may be placed by your dentist in the one appointment, or you might need to arrange another appointment for the placement of a crown (also known as a cap) to ensure a long-lasting seal and provide the tooth with additional strength and support.

After your initial appointment you might experience some mild discomfort. This can be managed with over-the-counter pain medications and will diminish within 48 hours.

The success rate of root canal treatment is very good, and full healing occurs in most cases. Sometimes, though, additional treatment may be necessary.

Dr Lucy Burchall
BHSc (Dent), MDent (La Trobe)
General Dental Care