Routine sensitivity, or something else?
Send a photo and a short description; an AHPRA-registered Australian dentist with askadent replies within 24 hours.
Send a photo — $25Sensitive tooth: why it hurts on cold, hot, or sweet
A brief sharp zing on cold, hot, or sweet — and then it settles — is almost always exposed dentine. Here's what's actually happening, what helps, and when the sensitivity has tipped into something that needs in-person care.
Written and reviewed by an AHPRA-registered dentist.
Why it happens
The common causes
Sensitivity means the inner layer of the tooth (dentine) has become exposed to the mouth — through one of these mechanisms.
Receding gums
As the gum line moves down, the part of the tooth that wasn't designed to be exposed (cementum, then dentine) ends up in the mouth. Brushing too hard with a hard-bristle brush is the most common cause; ageing is a slower second cause.
Worn enamel
Acidic diet (citrus, soft drinks, wine), reflux, or bruxism gradually thins the enamel until the dentine underneath starts to register temperature.
Cracked tooth or small cavity
A tiny crack or a cavity has reached the dentine layer. If you can localise the sensitivity to one tooth, this is the likeliest cause — and it's the most important one to catch early. Our broken-or-chipped-tooth severity guide covers the four kinds of break; caught small, this is usually a filling at typical Australian fees.
Recent dental work
A new filling, recent cleaning, or whitening can leave a tooth sensitive for 1–2 weeks while the nerve settles. If it's getting worse rather than better, get it checked — large fillings sometimes need replacing or stepping up to a crown at typical Australian fees.
While you arrange care
What helps tonight (and over weeks)
General guidance, not personal advice.
- Sensitivity toothpaste — twice a day for 2–4 weeks before you'll notice the difference. Brands work similarly; consistency matters more than brand.
- Soft-bristle brush. Don't scrub hard — the cause of receding gums is often the mechanical force of brushing.
- Avoid very hot, very cold, or very acidic food and drink until it settles.
- If a single tooth is the source, chew on the other side to let the nerve calm.
- OTC pain relief per the packet if needed.
Sensitivity toothpaste blocks the tiny tubes in dentine; it doesn't fix a crack, a cavity, or a dying nerve. If a week of consistent use makes things worse instead of better, the problem isn't routine sensitivity.
When sensitivity is more
Signs it's not just sensitivity
Routine sensitivity zings briefly and settles. The signs below mean the nerve is in trouble — book in. See also our reads on reading toothache patterns and signs of a tooth abscess and when antibiotics are not enough.
- Pain lingering 30+ seconds after the trigger goes away
- Spontaneous pain that comes on without a trigger
- Throbbing that wakes you, or pain worse lying down
- Pain on biting, not just on temperature
- Hot sensitivity on its own (without cold sensitivity)
- Visible swelling or a lump near the tooth
Any of those means dentist within a few days — sooner if there's swelling. Sensitivity plus facial swelling or fever is ED-level; see our guide to dental emergencies in Australia.
FAQ
Sensitive tooth: common questions
Get a second opinion
Quick zing, or something more?
Send a photo. An AHPRA-registered Australian dentist replies within 24 hours with a plain-English read.
Start a case — $25