In short: A short, sharp sting on cold, sweet or touch usually comes from exposed dentine — at receded gum margins, from worn enamel or after a treatment. That is common and treatable. A dull, lingering or throbbing pain is different: it points to inflammation inside the tooth and should be examined promptly.
Nearly everyone knows the feeling, and almost nobody knows which version of it matters. The distinction is simple and worth remembering: how long does it last after the trigger is gone?
The two kinds of pain
Short and sharp, stopping within seconds of removing the trigger — that is typically hypersensitivity of exposed dentine. Unpleasant, rarely dangerous, and well treatable.
Dull, lingering, throbbing, or waking you at night — that suggests the tissue inside the tooth is inflamed. This does not resolve on its own and should not be waited out. If a tooth hurts for minutes after cold, make an appointment.
Where the sensitivity comes from
- Receded gums: the root surface has no enamel and reacts directly. The most common cause in adults.
- Worn enamel: from acidic drinks, reflux, or brushing too hard with an abrasive paste. Hard scrubbing wears more than it cleans.
- Grinding: loads the tooth necks and cracks the surface. Often the sensitivity is the first sign of it.
- After treatment: a new filling or a professional cleaning can leave teeth reactive for days. That is normal and settles.
- Decay or a leaking filling: the cause that must be excluded before anything is treated as just sensitivity.
What actually helps
For genuine hypersensitivity, the reliable measures are a soft brush with correct technique rather than pressure, a toothpaste for sensitive teeth used consistently over weeks rather than days, professionally applied fluoride varnishes or sealants at the affected necks, and — where grinding is the driver — a night guard. What does not help: brushing harder, whitening strips, or abrasive polishing pastes, all of which make it worse.
A practical note on acid: after acidic food or drink, wait about half an hour before brushing. Enamel is briefly softened and brushing straight away removes more of it.
When to have it examined
If the pain lasts, if a specific tooth is reliably the source, if the gum around it bleeds or has receded visibly, or if it began after a knock. We locate the source, check for decay and cracks, measure the gum margins, and then treat the cause rather than only the symptom.
Frequently asked questions
Do sensitive-teeth toothpastes work?
Yes, for genuine hypersensitivity, but only with consistent use. They seal the fine channels in the dentine, which takes weeks rather than a single application.
Will receded gums grow back?
Not by themselves. Inflamed gums settle and swell down, but tissue that has receded does not regrow. In specific cases surgical coverage is possible.
Is sensitivity a sign of decay?
It can be. That is exactly why it should be examined rather than only managed with toothpaste — decay under a filling causes the same symptom.
My teeth hurt after a cleaning — is that normal?
Yes, for a few days, particularly if the gums were inflamed or necks are exposed. The fluoride applied at the end helps; if it persists beyond a week, tell us.
This article provides general information and does not replace a dental examination. Medically reviewed by Dr. F. J. Rodríguez Ruíz, MSc., dentist at A+ Dental, Düsseldorf-Oberkassel.