After
After root canal treatment
What is normal for the first few days, why the temporary filling is not the end of it, and the one instruction that decides whether the tooth survives.
Get help now if
Call 999
For anything life-threatening:
- Serious difficulty breathing, noisy breathing, or difficulty swallowing your own saliva
- Swelling under the tongue or in the floor of the mouth, or swelling closing the throat
- Collapse, or someone who cannot be roused
- A suspected severe allergic reaction — widespread rash or hives with breathing difficulty, swelling of the lips, tongue or throat, or feeling faint
Rare, and none of them waits.
Go to an emergency department
- Swelling that is spreading — towards or under the eye, or down the neck — particularly with a temperature, feeling unwell, or difficulty opening your mouth
A tooth with an infection that has already tracked into the tissues is the one situation on this page that can become serious quickly. It is worth knowing that, and worth not sitting on it overnight.
Ring a dentist, the same day
- Pain that is severe or getting worse after the first two or three days, rather than settling
- Swelling of the gum or face that is staying local
- The temporary filling has come out, broken, or feels loose
- A bad taste coming from the tooth, which can mean the seal has gone
- The tooth has cracked, or a piece has come away
- A tooth you cannot bite on at all after the first few days
What was done
The infected pulp has been taken out of the inside of the tooth, and the canals in the roots have been cleaned. Either they have now been sealed permanently, or they are packed with a dressing and the tooth is closed with a temporary filling until the next visit.
Either way, the tooth is quieter than it was and weaker than it looks.
The one instruction that matters
Do not chew on this tooth until it has been permanently restored.
Not "be a bit careful". Do not chew on it.
A root-treated tooth has had an opening cut through the top of it, and was usually already broken down before any of this started. What makes it liable to split is how much of it has been removed, not the root filling — there is less tooth left than there looks to be. Guy’s and St Thomas' put it plainly: "be careful when eating to reduce the chance of breaking your tooth."
And a temporary filling is exactly what it says. It is there to keep saliva out for a few weeks, not to take the force of a molar.
If the tooth cracks under the gum, it usually cannot be saved — which means losing it after everything you have just been through. That is the whole reason this paragraph is where it is on the page.
Go back and finish it
Root canal treatment is not finished when the pain stops. It is finished when the tooth has a permanent restoration — a proper filling, an onlay, or a crown.
NHS guidance is to go to any follow-up appointments after your treatment, and Guy’s and St Thomas' are blunter: "It is important for you to see your local dentist as soon as you can", because "Your tooth will still need more treatment."
If the tooth feels fine, that is not evidence the job is done. It has no nerve left in it. It cannot tell you it is cracking.
Today
While you are numb: nothing hot, and do not eat. The anaesthetic for a root canal is often a thorough one and can outlast the appointment by hours. There is a page on getting through it.
→ After a numbing injection
Once the feeling is back: eat on the other side, and keep eating on the other side.
Painkillers if you need them. Paracetamol first. If you take a blood thinner of any kind — warfarin, apixaban, dabigatran, rivaroxaban, edoxaban, clopidogrel, ticagrelor, prasugrel, dipyridamole, a daily injection such as enoxaparin, or aspirin a doctor put you on — take paracetamol and not ibuprofen or aspirin. Both add to the bleeding. If you are not on one, NHS guidance is paracetamol or ibuprofen. Follow the packet, do not exceed the dose on it, and take them regularly for the first day or two rather than waiting for the pain to build.
Be careful not to knock your mouth, which is NHS advice and sounds odd until you think about what the tooth is currently made of.
The next few days
Soreness is expected. NHS guidance says the area "may feel swollen and sore but it should get better in a couple of weeks", and Guy’s and St Thomas' that "It is normal for you to have some pain, which should ease over the next few days."
| Day 1 | Numb, then tender. Tender to bite on, and sometimes tender to touch. |
| Days 2–3 | Usually the peak. A dull ache, and the tooth feeling slightly raised or bruised. |
| Day 4 onwards | Settling. Pain that is increasing from here, rather than easing, is worth a phone call. |
| Weeks 1–2 | Normal. The tooth should become something you stop noticing. |
A flare-up can happen, usually in the first two days: the tooth becomes considerably more painful rather than less, sometimes with swelling. It is not a sign the treatment has failed and it is usually settled quickly — but it does need a dentist rather than more painkillers.
The gum may be the sore part, not the tooth, where the dam clip sat. That settles on its own in a few days.
Will it work?
Usually, and that honestly depends on the tooth — how much of it is left, how long the infection was there, how curved the roots are. It is a question for the person who has seen the X-ray.
What you can control is the half of it that is yours: go back, get it restored, keep it clean, and do not test it in the meantime.
Your dentist’s instructions come first
The instructions you were given by the dentist who treated you take precedence over anything on this page. They know what was done, what they sealed the tooth with, and what they want you to do before the next appointment; this page does not. Where the two differ, follow theirs.
Sources
- Root canal treatment — NHS, last reviewed 3 October 2025
- Extirpation aftercare advice — Guy’s and St Thomas' NHS Foundation Trust, reviewed June 2025
- Having root canal treatment — Wirral Community Health and Care NHS Foundation Trust
- Post-extraction haemorrhage, Management of Acute Dental Problems — SDCEP (escalation tiers)
Who to ring
Routes and numbers checked .
England
Ring your own dentist.
Otherwise NHS 111, by phone or at 111.nhs.uk, at any hour. They will arrange urgent treatment if you need it.
A GP cannot help with a dental problem.
Scotland
In working hours, ring your own practice — or your health board’s dental helpline if you are not registered with one.
Out of hours — from 6pm on weekdays, and from 6pm Friday to 8am Monday — 111 reaches NHS 24.
NHS 24 is a separate service from NHS 111 in England, on the same number.
Wales
Ring your own dentist.
Otherwise ring your health board's dental helpline — that is what NHS Wales asks you to do first. In Cardiff and the Vale it is 0300 10 20 247. In the Aneurin Bevan area (Blaenau Gwent, Caerphilly, Monmouthshire, Newport, Torfaen) it is 01633 744387, weekdays 9am to 12.15pm and 1.15pm to 4pm, with advice only outside those hours. In Betsi Cadwaladr, Cwm Taf Morgannwg, Hywel Dda, Swansea Bay and Powys, ring 111, at any hour.
Which number you ring depends on where you are, not where you are registered.
Northern Ireland
Ring your own practice first, whatever the day — they will tell you what out-of-hours arrangements they have. If you are not registered, ring local practices, and ask about the Dental Access Scheme if you cannot get seen.
At weekends and on bank holidays, the Emergency Dental Clinics triage by telephone on 028 2566 3510, lines open 8am to noon. You will be given an appointment if you need one.
Do not attend a clinic without an appointment. On a weekday evening or overnight there is no dental service at all — listen to your practice's answerphone, and use 999 or an emergency department only for the signs above.