What a root canal does
Inside every tooth is a soft core of nerve and blood vessels. When decay or a crack lets bacteria reach it, that tissue becomes infected and the tooth starts to ache. A root canal removes it, cleans and disinfects the canals it ran through, then fills and seals them so the infection cannot come back.
Why keep the tooth
The alternative is to take it out, and then there is a gap to deal with and the teeth either side start to drift. Keeping your own tooth in the bone is the point of the treatment.
What it is like
Root canals have a worse reputation than they deserve. The pain people associate with them is the infection, not the appointment. Once the tooth is numb it is much like having a deep filling done.
Afterwards
A tooth without its nerve is more brittle, so a crown is usually fitted to stop it splitting. It will no longer feel hot and cold, but it is still held in the bone and you still chew on it.
