You have had a filling, everything went smoothly, and now the tooth twinges at cold drinks or when you bite. A tooth sensitive after a filling is extremely common, almost always temporary, and rarely a sign that anything has gone wrong. Here is what is happening, how long it should last, and when it is worth ringing us.
On this page
- Why sensitivity happens
- How long should it last?
- What is normal
- What is not normal
- Sensitivity specifically when biting
- What helps in the meantime
- What happens if it persists
- The bottom line
Why sensitivity happens
Several things happen to a tooth during a filling, and each can leave it briefly irritable.
The nerve inside the tooth has been disturbed. Removing decay, particularly deep decay close to the nerve, causes mild inflammation in the pulp, which takes time to settle. The tooth has also been dried, etched and bonded, all of which are perfectly routine but not exactly restful.
There is often some minor trauma from the drill’s vibration and heat, even with water cooling. And if the cavity was deep, the remaining layer of dentine between the filling and the nerve may be thin, which makes temperature changes more noticeable for a while.
None of this means anything is wrong. It means the tooth is recovering.
How long should it last?
Most sensitivity settles within a few days to two weeks.
Deeper fillings take longer, sometimes several weeks, and occasionally a couple of months for a very deep one. What matters is the direction of travel: sensitivity should be steadily improving. Something that is gradually easing week by week is behaving exactly as expected.
What is normal
- A brief twinge with cold drinks or cold air, which stops as soon as the cold is removed
- Mild sensitivity to sweet things
- Slight tenderness in the gum around the tooth for a day or two, particularly after an injection
- A tooth that feels slightly different to your tongue while you get used to the new shape
- Symptoms that are noticeably improving week on week
What is not normal
Ring us if you notice:
- Pain that lingers for many seconds or minutes after the cold or hot has gone, rather than stopping immediately
- Spontaneous pain, arriving without any trigger, particularly at night
- Sensitivity that is worsening rather than improving after the first fortnight
- Throbbing pain, or any swelling
- A filling that feels high when you bite together
Lingering pain to heat especially, and pain that wakes you, can indicate the nerve has become more seriously inflamed. That is worth knowing about early, because it may need root canal treatment, and our post on whether root canal treatment hurts may set your mind at rest on that front.
Sensitivity specifically when biting
This one has a simple and satisfying fix, so it is worth separating out.
If the tooth is only uncomfortable when you bite down, the filling may be very slightly high, meaning that tooth is taking more force than its neighbours. It happens because your mouth is numb when the filling is shaped, so your bite cannot be checked as precisely as usual.
An adjustment takes a couple of minutes, needs no numbing, and usually resolves the problem immediately. Please do not put up with it for weeks; a high filling that is left can bruise the ligament around the tooth and prolong the discomfort unnecessarily.
What helps in the meantime
- Use a sensitive toothpaste, brushing it in gently around the tooth and, if you like, leaving a smear on the area overnight rather than rinsing it off.
- Avoid extremes of temperature for a week or two.
- Chew on the other side if biting is uncomfortable.
- Keep brushing the tooth normally. Avoiding it lets plaque gather, which makes sensitivity worse rather than better.
- Ordinary painkillers as the packet directs, if needed for the first few days.
The NHS guidance on sensitive teeth has further general advice.
What happens if it persists
If sensitivity is not settling, come in and we will find out why. The tooth is examined, your bite checked, and the filling assessed, sometimes with an X-ray.
Possible outcomes range from a simple bite adjustment, through replacing or relining the filling, to root canal treatment where the nerve has been more seriously affected. Occasionally a deep filling in a heavily broken-down tooth turns out to need something stronger, and our posts on crowns and inlays and onlays explain those options.
Most of the time, though, the answer is simply reassurance and a little more patience. Our page on white fillings explains what is involved in the treatment itself.
The bottom line
Sensitivity after a filling is normal, usually settles within days to a fortnight, and is a sign of a tooth recovering rather than failing. Sensitivity that lingers after the trigger has gone, arrives spontaneously, or worsens after two weeks deserves a look, and discomfort when biting is often a two-minute adjustment.
If your tooth is not settling as it should, ring us on 01255 422506. Our posts on rebuilding worn teeth and how long crowns last cover what happens when a tooth needs more than a filling.
This article is general information rather than personal dental advice. Every mouth is different, so please speak to your dentist about your own teeth.