What does this mean?
The active ingredient in whitening products passes through the enamel and reaches the inside of the tooth, where it irritates the nerve for a time. That is why cold, heat or even air can cause a short, sharp pain in the tooth after whitening.
In most people the sensitivity peaks within a day or two and fades within three or four days, at most within a week. Because it is a temporary and reversible irritation, it does not mean lasting damage.
Some teeth react more strongly: cracked or worn enamel, an exposed root surface and the edges of old fillings are examples. If the sensitivity lasts beyond a week, settles on a single tooth, or turns into pain that comes on its own, the cause may be something other than the whitening.
Four causes are common behind sensitivity after whitening, and how long it lasts and how many teeth it affects separate them.
Likely causes
What helps at home?
- Pause the whitening for a few days and do not restart until the sensitivity has gone
- Use a desensitising toothpaste and avoid very cold, very hot and acidic food
- Use a soft brush and do not scrub the teeth hard
- Do not use the whitening product more often or for longer than the instructions say
- Sensitivity that lasts longer than a week
- Pain that comes on its own and settles in one tooth
- Burning, whitening or bleeding of the gum
- Swelling or a bump on the gum together with the sensitivity
Frequently asked questions
- How long does sensitivity last after whitening?
- In most people it fades within a few days, at most within a week. If it continues after that, or settles in one tooth, a dentist should check it.
- Does whitening damage the teeth?
- Sensitivity shows the nerve is temporarily irritated and does not mean lasting damage. It matters that the product is used as instructed and no more often than needed; if pain continues, stop using it and see a dentist.
- What eases the sensitivity?
- Pausing the whitening, using a desensitising toothpaste and avoiding very cold, hot or acidic food helps most people. If it does not settle despite these, the cause should be looked into at an examination.
This content is for general information and does not replace an in-person examination. Symptoms overlap between conditions, and a diagnosis can only be made clinically.