The reputation is worse than the appointment. Ask us and we will talk you through it.

When a tooth is badly infected, most people assume it is coming out. Usually it is not. Root canal treatment clears the infection from inside the tooth and leaves the tooth itself where it is — which is almost always the better outcome, because nothing we can put in a gap works quite as well as the original.

It has an unfortunate reputation. In practice it is a long appointment rather than a painful one.

Every tooth has a chamber inside it holding nerve and blood supply. Root canal treatment deals with that chamber once it has become infected. Infection gets in through:

• Decay that has been left long enough to reach the nerve
• A tooth that has been drilled and refilled repeatedly over the years
• A crack, or a knock to the tooth
• An old filling that has started to leak at the edges

Once infected, that tissue will not recover. It is removed, the canals are cleaned and disinfected along their length, and then sealed so nothing can get back in.

• Severe ache, particularly when biting on that tooth
• Sensitivity to hot or cold that lingers long after the drink has gone
• Gum swollen or tender over the root
• The tooth going darker than its neighbours
• A small blister on the gum, which is an abscess draining

Pain that stops abruptly is not good news either — it usually means the nerve has died rather than recovered. Either way, get it looked at.

1. Examination and x-rays — to see the root shape and how far the infection has travelled.
2. Numbing — the same anaesthetic as a filling, and we check it before starting.
3. Cleaning — a small access hole, then the canals are cleaned and shaped along their whole length. This is the part that takes the time.
4. Sealing — the canals are filled with a biocompatible material so nothing can recolonise them.
5. Restoring — a filling or, more often on back teeth, a crown to stop the tooth splitting.

£296 for a front tooth, £425 for a premolar, £640 for a molar — a molar has more canals and takes considerably longer. Plan members save 10%.

Straightforward, in most cases:

• Some tenderness for a few days, particularly on biting
• Ordinary painkillers deal with it
• Back to normal the same day or the next
• Come back and get it crowned — a root-treated back tooth left unrestored will eventually split, and then it really does have to come out

No. The anaesthetic does its job and the appointment feels much like having a large filling done — long rather than painful. Most people arrive in pain and leave without it, because the infection causing it has gone.

Root treated and properly crowned, a tooth can go on doing its job for decades.

You will know the cost and how many visits it needs before we begin.