A sharp twinge when you sip a cold drink, bite into ice cream or brush near the gum line is a very common complaint. Tooth sensitivity can range from a mild, occasional annoyance to pain that changes what you eat. Usually it has a clear cause, and in many cases it can be eased.
Why teeth become sensitive
Under the hard enamel of the crown, and under the gum on the root, is a layer called dentine. Dentine contains thousands of microscopic tubes leading towards the nerve. When dentine is exposed, hot, cold, sweet or acidic things can stimulate the nerve through these tubes, causing a short, sharp pain. This is often called dentine hypersensitivity.
Common causes
Gum recession
When gums pull back, the root surface is exposed. Roots don’t have enamel, so they’re more sensitive. Recession can be caused by gum disease, brushing too hard, or simply ageing.
Worn enamel
Enamel can be worn by brushing too hard, abrasive toothpastes, grinding, and especially by acid erosion from soft drinks, sports drinks, juice, wine, citrus and reflux.
Tooth grinding
Grinding and clenching wear down enamel and can cause tiny cracks. See our article on teeth grinding.
Decay or a broken filling
A cavity, or a gap around an old filling, can let stimuli reach the nerve. This kind of sensitivity often lingers or comes with sweet foods.
Cracked tooth
A crack can cause sharp pain when you bite or release, or with cold.
After dental treatment
Teeth may be sensitive for a short time after a clean, a new filling, a crown or whitening. This usually settles within days to a few weeks.
What can help at home
- Use a toothpaste for sensitive teeth twice a day. Products with potassium nitrate, stannous fluoride or other desensitising ingredients can reduce sensitivity over two to four weeks. You can also rub a little onto sensitive areas before bed and don’t rinse it off.
- Use a soft toothbrush and gentle technique. Scrubbing hard doesn’t clean better.
- Cut back on acidic food and drinks, and drink water afterwards. Wait 30 to 60 minutes after acidic foods before brushing.
- Avoid whitening toothpastes if they make things worse.
- Don’t stop cleaning sensitive areas. Plaque build-up can make sensitivity worse.
What your dentist can do
Your dentist will first find the cause. Treatment depends on what they find and may include:
- applying a fluoride varnish or desensitising agent
- sealing exposed root surfaces with a bonded coating or tooth-coloured filling
- treating decay or replacing a leaking filling
- a night guard if you grind
- treating gum disease, or referring for a gum graft in some cases of recession
- root canal treatment, if the nerve is irreversibly inflamed and other treatments haven’t helped
When to see a dentist
Book a check-up if sensitivity lasts more than a couple of weeks, is getting worse, affects one particular tooth, lingers for more than a few seconds after the trigger, or comes with throbbing pain or swelling. These can be signs of decay, a crack or a problem with the nerve that needs treatment.
Sensitivity and cold weather
Some people notice sensitivity more in winter, when breathing in cold air. If that’s you, the same steps above can help.
Read more about preventive dentistry or book a check-up with our team.
Frequently asked questions
How long does sensitive toothpaste take to work?
Many people notice an improvement within two to four weeks of using a desensitising toothpaste twice a day. Keep using it to maintain the effect.
Is it normal to have sensitivity after a filling?
Mild sensitivity after a new filling is common and usually settles within a few days to a few weeks. If it gets worse, lingers or is painful when biting, contact your dentist.
Can sensitive teeth be a sign of something serious?
Usually sensitivity is caused by exposed dentine, but it can also be a sign of decay, a crack or a problem with the nerve. Sensitivity that lingers or is concentrated in one tooth should be checked.
Should I stop whitening if my teeth are sensitive?
With take-home whitening, you can usually wear the trays for shorter periods or take a break. Talk to your dentist, who may recommend a desensitising treatment.
Does brushing harder clean better?
No. Brushing too hard can wear enamel and push gums back, making sensitivity worse. Use a soft brush and gentle circular movements.
Book at Parramatta Dentistry
Parramatta Dentistry is at Suite 25, Level 3, 27 Hunter Street, Parramatta, a short walk from Parramatta Station. We’re open Monday to Friday, 9am to 6pm, and HICAPS is on site, so you can claim from your health fund on the day and pay only the gap, if there is one. Call (02) 8090 1109 or book online.
This article is general information only and isn’t a substitute for personalised advice from your dentist.