Root canal treatment

What is inside the canal

In the middle of a tooth, under the enamel and dentine, sits a chamber of soft tissue with the nerve and blood vessels. Narrow canals run from that chamber towards the tip of the root. Front teeth usually have one, premolars one or two, molars three or more. That is why the price differs by the number of canals: each one is treated separately.

When bacteria from deep decay reach that tissue, it becomes inflamed. Inflammation in a closed space builds pressure, and pressure makes the kind of pain that throbs and wakes you at night. More on throbbing toothache is in a separate article.

When it is needed

• Pain that does not stop when the trigger stops — the tooth still hurts after you have drunk something cold.
• Pain that wakes you at night or comes on with heat.
• A tooth that has darkened after a knock, even when nothing hurts.
• Swelling of the gum by the root, or a bump that appears and goes down.
• A deep filling with lasting sensitivity underneath it.

Not every sensitivity means the canal is involved. A tooth with an exposed root or a cracked filling gives a similar feeling and is treated differently. An X-ray and a test of the tooth’s response tell these apart; that is done at an examination, not assumed.

How the treatment goes

1. Anaesthetic and isolation of the tooth, so that no saliva enters the canal during the work.
2. Opening the tooth and finding the canals; an X-ray shows how long they are.
3. Cleaning and shaping the canals with instruments, rinsing with a solution that removes debris.
4. Medication in the canal between visits, where the inflammation is marked.
5. Filling the canals and closing the tooth, then a check X-ray.
6. Rebuilding the crown of the tooth — a filling or, on a badly damaged tooth, a crown.

Usually two or three visits, a few days apart. One visit is possible where there is no marked inflammation; a tooth with several canals, or a re-treatment, takes longer.

After treatment

For a few days the tooth can be tender to bite on, while the tissue around the root tip settles. If the pain grows instead of easing, get in touch; that is dealt with, but not by waiting.

A treated tooth is more brittle than a sound one: it has lost its inner tissue and often part of its crown. On back teeth a crown is therefore usually made after treatment, because a filling on a weakened molar splits at the root. What your tooth needs is seen after treatment, not before.

Re-treatment

A tooth treated earlier can flare up again: a canal was left untreated, the filling leaked, or decay got in under the old restoration. The old material is then removed and the canal treated afresh; this is more demanding than a first treatment and is charged per canal. When even that is not enough, the next step is surgical — removal of the root tip.

Does it hurt during the work?

It is done under anaesthetic. Say so if you feel something before it becomes uncomfortable — the anaesthetic is topped up, and a pause is always possible.

Why not take the tooth out, if the nerve is gone anyway?

A tooth without a nerve still has a root in the bone and carries the load of chewing. Once it is out, the neighbouring teeth move, and replacing it costs more than treating it.

What does it cost with three canals?

The price depends on the number of canals and is in the price list on this page. If a crown is needed afterwards, that is separate work and a separate item.

Can it be put off?

The pain can stop by itself once the tissue dies, but the inflammation then moves towards the root tip and the bone around it. Putting it off usually means a bigger procedure later.