Sensitive teeth: why teeth hurt with cold, what helps and when it is not sensitivity

What is tooth sensitivity?

Tooth sensitivity, or more precisely dentine hypersensitivity, is a short, sharp pain caused by a stimulus such as cold, a puff of air, touch, or something sweet or sour, which cannot be attributed to any other defect or disease of the tooth. That is the definition used in the literature since 1997, and its last part matters most: sensitivity is diagnosed only after decay, a crack and inflammation of the pulp have been ruled out.

The pain comes from exposed dentine, the tissue that lies beneath the enamel on the crown and beneath the gum on the root. Dentine is crossed by tiny tubules filled with fluid; when a stimulus moves this fluid, the nerve endings in the pulp react. This explanation is called the hydrodynamic theory.

A 2019 meta-analysis estimates that tooth sensitivity affects about 1 in 9 adults (11.5%), although the results of individual studies vary widely. In a European study of 3,187 people aged 18 to 35, carried out in dental surgeries, a blast of cold air provoked pain in 41.9% of participants, while 26.8% reported sensitivity in a questionnaire.

Why do teeth hurt with cold? The most common causes

Teeth hurt with cold when the dentine loses its cover: the enamel on the crown, or the gum and cementum on the root. This happens most often at the necks of the teeth, along the gum line, which is why sensitivity to cold often affects several neighbouring teeth at once.

In the European study of young adults, sensitivity was linked above all with erosive tooth wear and gum recession, and also with reflux, vomiting, energy drinks, smoking and an acidic diet. The list brings together the causes described in reviews.

• Enamel erosion: enamel dissolved by acids from drinks, fruit and juices, or from the stomach in reflux and frequent vomiting.
• Brushing too hard or with a hard toothbrush, which wears away the tissues at the necks of the teeth.
• Grinding and clenching the teeth (bruxism), which wears down tooth surfaces and can expose the dentine.
• Receding gums (recession), which expose the root, covered only by a thin layer of cementum.
• Gum disease and its treatment, after which exposed root surfaces are sometimes more sensitive.
• Teeth whitening, after which sensitivity is common but usually passes within a few days.

Sensitivity or something else? Symptoms and their possible causes

True dentine hypersensitivity stops once the stimulus is gone: the pain lasts seconds, not minutes. Pain that lingers after something cold or hot suggests pulpitis, and pain on biting suggests a cracked tooth; similar symptoms can also come from decay, a leaking or new filling, recent whitening and gum disease.

The table helps you judge how urgent a visit is, but it does not replace an examination. A diagnosis requires looking at the tooth, and often an X-ray as well.

Which toothpaste for sensitive teeth works?

A toothpaste for sensitive teeth works if it contains an ingredient that seals the dentine tubules or calms the nerve’s response, and if it is used every day. A 2020 network meta-analysis (125 studies, 12,541 patients) showed, with moderate certainty, an advantage over ordinary fluoride toothpaste for the groups of ingredients in the list below.

Use a toothpaste for sensitive teeth daily for several weeks before judging the effect. The UK’s Oral Health Foundation points out that the effect lasts only with regular use, and advises rubbing a small amount of toothpaste into the painful spot in the evening.

Check the ingredients on the packaging, because different ingredients performed best against different stimuli. A brand name and the words “for sensitive teeth” say nothing in themselves.

• Stannous fluoride, alone or combined with potassium salts: reduced pain caused by touch.
• Calcium sodium phosphosilicate: reduced pain caused by touch and cold.
• Arginine: reduced pain caused by a puff of air.
• Strontium salts and potassium salts, for example potassium nitrate: reduced pain caused by touch.

What else helps with sensitivity at home?

Home remedies for sensitive teeth are mainly about not exposing any more dentine. Changing habits works slowly, but it protects the enamel and gums from further loss.

• Use a soft toothbrush and brush with gentle movements, without scrubbing hard.
• Brush twice a day with fluoride toothpaste, and after brushing spit the toothpaste out instead of rinsing with water.
• Cut down on how often you have acidic drinks and do not hold them in your mouth; UK guidance allows drinking them through a wide straw.
• After vomiting, rinse your mouth and do not brush straight away. Outside this situation there is no strong evidence that waiting to brush after an acidic meal protects the enamel.
• If you have frequent heartburn or reflux, have it treated by a doctor, because stomach acid is one of the causes of erosion.
• If someone has noticed that you grind your teeth at night, tell your dentist.

How does a dentist treat sensitive teeth?

Treatment of sensitivity at the dentist starts with checking that it really is sensitivity, and then most often consists of covering the sensitive areas with a preparation that seals the dentine tubules. A network meta-analysis of 40 studies showed that sealing agents, such as varnishes, as well as lasers and combinations of the two, work better than placebo and do not differ significantly from one another.

When the necks of the teeth are clearly worn, the dentist may cover them with a filling, and where the gum has receded, assess whether a procedure to cover the recession is indicated. They may also recommend a toothpaste with a higher fluoride concentration.

In the clinic’s price list, the item “Leczenie nadwrażliwości Duraphat za 1 ząb” (sensitivity treatment with Duraphat, per tooth) costs 40 zł, and “Leczenie nadwrażliwości preparat Tokuyama” (sensitivity treatment with the Tokuyama product) 100 zł. The number of teeth and the choice of preparation depend on the examination; the final scope and cost are agreed at the visit, and prices may change.

Sensitivity after whitening: how long does it last and what should you do?

Sensitivity after teeth whitening is common and usually temporary. The American Dental Association (ADA) states that up to two thirds of people feel mild or moderate sensitivity at the start of treatment; with trays or strips it may appear within 2 to 3 days and usually resolves by the fourth day after treatment ends.

Gum irritation, the second common symptom, is also usually temporary according to the ADA. If pain after whitening is severe or does not pass after a few days, contact the dentist supervising the whitening before you apply the next dose of gel.

Whitening methods, the rules on peroxide concentrations and contraindications are described in a separate article on teeth whitening.

When should you see a dentist about sensitive teeth?

It is worth seeing a dentist about sensitive teeth if the pain is severe, lasts longer than a few weeks, affects one tooth or came on suddenly. That is the Oral Health Foundation’s advice, because this pattern more often means decay, a crack or infection than exposed dentine. In any of the situations in the list, contact a dentist or doctor.

• Pain lingers for more than a few seconds after something cold or hot, or comes on without a trigger, including at night.
• The tooth hurts when you bite, or you can see a crack or a cavity in it.
• Toothpaste for sensitive teeth has not helped after several weeks of regular use.
• Gum swelling, a bad taste in the mouth or a fever appears: you need same-day dental care.
• Swelling of the face or neck makes breathing or swallowing difficult: go to the hospital emergency department (SOR) or call 112, the emergency number.

How it works at DentalBlue

At DentalBlue in Białystok, sensitivity is assessed during a dental examination. A “Wizyta bez bólu” (visit without pain) includes a panoramic X-ray, a consultation, an examination and a written treatment plan (300 zł in the clinic’s price list), and a “Wizyta z bólem” (visit in pain) a panoramic X-ray, a consultation, an examination and pain relief (340 zł). Intraoral X-rays, needed when decay or a crack is suspected, are taken in the clinic’s own radiology unit. The clinic is open Monday to Friday from 8:00 to 20:00 and on Saturdays from 8:00 to 16:00.