What Happens During Root Canal Treatment? A Step-by-Step Guide
Dr Nader Gavgani, GDC 75484Published 7 min read
What actually happens during root canal treatment
Root canal treatment removes infected or dying nerve tissue from inside a tooth, disinfects the hollow canals in the root, and seals them — so the tooth stays in your mouth instead of being taken out.
The reputation root canal treatment has doesn't match what it actually involves. The severe pain people associate with it is the infection itself — what brings you in in the first place. The treatment is what removes that pain, not what causes it.
You're numbed fully before anything starts. Most patients say it felt much like having a routine filling — because mechanically, it's a similar procedure, just reaching further into the tooth.
The appointment, step by step
1. Numbing and isolating the tooth
The area is fully numbed, and a small rubber sheet is placed around the tooth to keep it dry and free of saliva during the treatment.
2. Reaching the infected tissue
A small opening is made in the top of the tooth to reach the pulp chamber and the canals inside the root, where the infected or dying tissue is.
3. Cleaning and shaping the canals
Fine instruments remove the infected tissue and clean and shape each canal. Molars have more canals than front teeth, which is why they usually take longer.
4. Sealing the tooth
Once the canals are clean and dry, they're filled with a biocompatible material and sealed, and the opening in the tooth is closed with a filling.
5. A crown, where one is needed
Removing the pulp leaves a tooth more brittle. On a back tooth, a crown usually follows to hold it together under the force of chewing — front teeth can sometimes be restored with a filling instead.
One or two appointments is typical. Which applies to you depends on the tooth and how much infection there is — you'll be told which before you start.
Related reading
- Dental crowns explained — what usually comes next, and why.
- Missing tooth? Implants vs bridges vs dentures — if a tooth genuinely can't be saved.
- Sedation dentistry for nervous patients — if anxiety is what's holding you back from booking.
Questions
Frequently asked questions
Can a tooth be root-treated more than once?
Yes. Re-treating a previous root canal is possible and is priced as an addition of £100 to the standard fee, if the original treatment needs revisiting.
How soon can I eat afterwards?
Wait until the numbness has fully worn off so you don't bite your cheek or tongue without realising, then eat on the other side of your mouth until any tenderness settles — usually just a day or two.
What if the pain doesn't go away after treatment?
Some tenderness for a few days is normal while the tooth settles. Pain that's severe, worsening, or accompanied by swelling isn't — ring us rather than waiting it out.
In pain now, or just want it looked at?
Reviewed by Dr Nader Gavgani, GDC 75484