Mild tooth pain after filling a cavity is common, especially sensitivity to cold, and it usually settles over a few days to a couple of weeks. Pain that gets worse, lingers after hot or cold, starts on its own, wakes you at night or makes it hard to bite needs to be checked by your dentist.
This guide explains what’s normal, what isn’t and when to call. If you have severe pain or swelling, see what counts as a dental emergency.
Normal sensitivity after a filling
Removing decay and placing a filling can irritate the pulp, the soft tissue inside the tooth that contains the nerve. The deeper the cavity, the closer the filling sits to the pulp and the more likely the tooth is to be sensitive for a while. Your gum can also feel sore where the injection was given or where equipment rested during treatment.
Signs that usually fall within the normal range include:
- short, sharp twinges with cold drinks, cold air or sweet food that fade within a few seconds
- mild tenderness when biting for a day or two
- a sore gum around the tooth or at the injection site
- symptoms that improve a little each day
Easing normal sensitivity
- Use a toothpaste for sensitive teeth and a soft toothbrush.
- Avoid very cold, hot or sugary food and drinks for a few days.
- Chew on the other side until the tooth feels comfortable.
- If needed, take over-the-counter pain relief such as paracetamol or ibuprofen, taken as directed on the pack, if it’s safe for you.
When tooth pain after filling isn’t normal
Your bite feels high
While your mouth is numb, it’s hard to tell whether a new filling is slightly too high. If it is, that tooth hits first every time you bite, which can bruise the ligament around the root and make the tooth increasingly sore. Signs include the tooth meeting before the others, pain on biting that isn’t improving, and an ache in the jaw.
This is usually easy to fix. Your dentist checks your bite with thin marking paper and smooths the high spot. Leaving it can also put extra stress on the filling.
Signs of an irritated or inflamed nerve
Dentists call inflammation of the pulp pulpitis. When it’s mild, the pulp can often recover, and pain only comes with a trigger and settles quickly. When the pulp is too inflamed to recover, the signs are different:
- pain that lingers for 30 seconds or more after hot or cold
- pain that starts on its own, without a trigger
- throbbing pain that keeps you awake or wakes you at night
- sensitivity to heat that cold seems to ease
- pain that is getting worse over days rather than better
- swelling, a bad taste or a pimple-like lump on the gum, which can mean infection
If the pulp can’t recover, root canal therapy or removing the tooth may be needed. This is more likely when the decay was very deep, and your dentist may have mentioned the possibility before treatment.
Referred pain
Pain from one tooth can be felt in nearby teeth, or even in the opposite jaw, because the nerves share pathways. An ache that seems to come from a neighbouring tooth may actually be from the one that was filled, or the other way around. Your dentist can test each tooth to find the source.
Other possible causes
- a crack in the tooth, which often hurts when you bite down or release
- a brief zap when two different metal fillings touch, which usually settles
- sinus congestion, which can make upper back teeth ache
- a rough edge or overhang that traps food or irritates the gum
When to go to hospital
Pain after a filling is rarely a hospital matter, but call 000 or go to your nearest hospital emergency department if you have:
- difficulty breathing or swallowing
- swelling that is spreading to the eye, neck or floor of the mouth
- bleeding that won’t stop after 15–20 minutes of firm pressure
- a high temperature with facial swelling, or you feel very unwell
Outside clinic hours, healthdirect on 1800 022 222 offers 24/7 nurse advice.
When to call your dentist
- sensitivity isn’t improving after a week or is still there after two weeks
- your bite feels high or uneven
- pain lingers, starts on its own or wakes you
- you notice swelling, a bad taste or a lump on the gum
- the filling feels rough, cracked or loose, or floss keeps catching or shredding
We aim to see urgent problems as soon as possible, often on the same day. You can contact our emergency dentist in North Sydney, or read more about our dental fillings.
What your dentist may do
- check and adjust your bite
- test the tooth with cold and gentle tapping, and take an X-ray
- apply a desensitising treatment to the tooth
- replace the filling, sometimes with a soothing lining underneath
- recommend root canal therapy or an extraction if the nerve can’t recover
At our North Sydney clinic, your dentist will explain what they find, your options and any costs before going ahead.
Frequently asked questions
How long should a tooth hurt after a filling?
Mild sensitivity usually settles within a few days to a couple of weeks. If pain is getting worse, lingers after hot or cold, or wakes you at night, call your dentist rather than waiting.
Why does my tooth hurt when I bite after a filling?
The filling may be slightly high, so the tooth takes more pressure than it should. A quick bite adjustment often helps. Pain on biting can also come from a crack or an inflamed nerve, so it’s worth having it checked.
Does pain after a filling mean I need a root canal?
Not usually. Most sensitivity settles on its own. Root canal therapy may be needed if the nerve is too inflamed to recover or has become infected, which your dentist can assess with tests and an X-ray.
Can I take pain relief after a filling?
Over-the-counter pain relief such as paracetamol or ibuprofen, taken as directed on the pack, may help if it’s safe for you. Ask a pharmacist if you take other medicines or have a health condition.
Need help now?
North Sydney Dentistry is at Level 1, Suite 102/71 Walker St, North Sydney, a two-minute walk from North Sydney station. We’re open Monday to Friday, 9am to 6pm, and keep time aside for urgent problems where we can. Call (02) 8090 1108 or book online.
This article is general information only and is not a substitute for advice from your own dentist or doctor. Any surgical or invasive procedure carries risks. Before proceeding, you should seek a second opinion from an appropriately qualified health practitioner.