Sensitive Teeth

Do you experience a short, sharp pain to cold drinks, food, air, hot, sweet, sour, or touch (for example, when brushing your teeth)? This sensation can be alarming, but most of the time, it’s just the result of “sensitive teeth”.

What causes sensitive teeth?

Sensitive teeth are usually caused by exposed dentine (the inner part of the tooth).

Dentine has wee tunnels or connections (dentinal tubules) running through it that link to the tooth nerve. When dentine is exposed, the nerve fibres are stimulated. Unfortunately, they are pretty stupid – they carry only pain receptors, not hot/cold/sweet or anything else useful, just pain. If anything stimulates them, then “pain” is sent back.

Dentine can be exposed for a variety of reasons:

• sometimes the enamel has worn away
• sometimes there’s a gap between the enamel on the crown and the cementum that covers the root surfaces
• sometimes the cementum has been worn away.

Most commonly, there’s a bit of gum recession which makes teeth sensitive by exposing parts of the root surface. It’s usually easy enough to manage sensitive teeth by using a suitable desensitising toothpaste, or the dentist can use stronger materials. 

How do you stop sensitive teeth pain?

1. Use a toothpaste for sensitive teeth!

There are many toothpastes to help with sensitive teeth. But they don’t all contain the same active ingredients. So if one toothpaste for sensitive teeth doesn’t work for you, try another type.

Below, we’ve listed the active ingredients in approximate order of effectiveness ¹²³:

1. Stannous fluoride

Stannous fluoride works by forming a barrier on the dentine surface, which acts like a protective shield. Examples in the UK and Ireland include Oral-B Pro-Expert Professional Protection and Sensodyne Rapid Relief toothpaste. There is good evidence that stannous fluoride works well as a desensitising agent.

2. Arginine / Pro-Argin

Arginine (e.g. Colgate Sensitive Pro-Relief toothpaste) can also help with sensitive teeth, although the evidence is not quite as good as it is for stannous fluoride.

3. Calcium sodium phosphosilicate (aka NOVAMIN)

Again, there’s moderate evidence that this works. It is sold as Sensodyne Repair & Protect with Novamin in the UK.

4. Potassium Nitrate

This is the most commonly used desensitising agent in toothpastes, even though it doesn’t seem to work as well as other types of desensitising agents ⁴. These pastes deposit ions into the tunnels to stop the nerves from firing.

5. Strontium acetate and strontium chloride

These have a similar chemical structure to calcium that are meant to replace some of the lost calcium and block the exposed dentinal tubules. Again, it’s not clear how effective they are ⁴.

How to use toothpaste for sensitive teeth

• Use instead of your normal toothpaste. Make sure that you work the paste right into the bristles of the brush. Brush twice a day. When finished, spit out and don’t rinse!
• If you prefer the taste of your regular toothpaste and for more rapid relief of symptoms, just apply a smear of desensitising paste with your finger tip to the sensitive areas last thing at night. Do not rinse or brush or anything, just go to bed. While you sleep, your saliva switches down a gear so the paste will sit undisturbed till the morning.
• Many of these toothpastes need to be used for 3-4 weeks to have a significant effect. So don’t give up if it doesn’t work straight away.
• Desensitising toothpastes can be used forever. Still, you may see a warning on the packaging not to use them for more than a month. But this is just a legal requirement, so you don’t put off seeing a dentist when there may be a more serious problem.

2. Tackle the causes of sensitive teeth

Toothpastes for sensitive teeth deal with the effects of exposed dentine. But you may also want to tackle the causes. Here are some top tips:

1. Don’t brush too often or too hard.
2. Use an electric toothbrush which has a pressure sensor and timer.
3. Use the technique recommended by the toothbrush manufacturer.
4. Don’t scrub in the same way you would with a manual toothbrush.
5. Avoid frequent acid exposure. Why? Because acidic drinks and foods can open up the little tunnels (tubules) which may have partially closed.
6. If you grind or clench, wear a nightguard.

3. What can dentists do about sensitive teeth?

• Your dentist or hygienist may be able to paint special fluoride gels, rinses or varnishes onto the affected teeth. Fluoride varnish helps by initially sealing things over and encouraging the little nerve fibres to retreat back a bit and seal themselves off in their wee tunnels.
• Or they may make you fluoride trays which you can use at home.
• Seal & Protect is a light-cured resin material that “seals” off the dentinal tubules from the external environment. It can reduce sensitivity for up to twelve months. However, it’s fairly expensive and your dentist will need to reapply it once it has worn off.
• If you grind your teeth in your sleep, ask your dentist about a mouthguard that you can wear at night.

The bottom line

There are many causes for sensitive teeth. In addition to using a toothpaste for sensitive teeth, you may also want to look at what might be causing your teeth to be sensitive. Tackling the causes of sensitive teeth directly can be a great help. And if one toothpaste doesn’t work for you after several week, do try others – they all work slightly differently.

You may also like:

• How to Prevent Acid Damage
• How to Prevent Tooth Decay
• What can I do if I’m terrified of the dentist but need to go?

Sources of Information

Illustration of exposed dentinal tubules: reprinted from Journal of Oral Biosciences Volume 59, Issue 4, Ji won Kim and Joo-Cheol Park, “Dentin hypersensitivity and emerging concepts for treatments”, Pages 211-217, November 2017, with permission from Elsevier.

1. West NX, Seong J, Davies M. Management of dentine hypersensitivity: efficacy of professionally and self‐administered agents. Journal of Clinical Periodontology, Vol. 42, Issue S16.[↩]
2. Poulsen S, Errboe M, Lescay Mevil Y, and Glenny A-M. Potassium containing toothpastes for dentine hypersensitivity. Cochrane Database of Systematic Reviews 2006, Issue 3. DOI: 10.1002/14651858.CD001476.pub2.[↩]
3. Karim BFA, Gillam DG. The efficacy of strontium and potassium toothpastes in treating dentine hypersensitivity: a systematic review. Int J Dent. 2013; 2013: 573258. DOI: 10.1155/2013/573258[↩]
4. Karim, B. F., & Gillam, D. G. (2013). The efficacy of strontium and potassium toothpastes in treating dentine hypersensitivity: a systematic review. International journal of dentistry, 2013, 573258. https://doi.org/10.1155/2013/573258[↩][↩]