Sensitive teeth are a pain!

Sensitivity in teeth is a short, sharp pain, which comes when the teeth are stimulated by hot or cold or very sweet liquids or food.  The most likely area on the tooth is along the edge of the gum.  It is also quite common to experience sensitivity on the occlusal (biting edge) surface of the tooth.

Sensitive teeth are more often found on the left hand side of the mouth, because right-handed people often are too vigorous in their tooth brushing habits.  It affects about one third of the population, but is only treated in about a third of those cases.  It can affect all age groups, from the young adults through to old age.

Sensitive teeth (correctly known as Dentine hypersensitivity) is a most annoying problem to have, but unfortunately most cases are never reported to the dentist, and thus go undiagnosed and untreated.

The Cause of Sensitive Teeth

When the gum recedes along the edge of the tooth, the underlying dentine is exposed, and is subject to some torrid conditions in the mouth.  Vigorous tooth brushing, or the use of too much abrasive toothpaste, will wear away the outer layer of the dentine and result in sensitivity.  The area of the tooth around the gum line has more dentinal tubules, each of which has an internal diameter twice the size of regular dentinal tubules.  

This increase in quantity and diameter of the tubules aids in making the dentine in this area more susceptible to sensitivity than in other areas of the tooth.

A cold stimulus will draw fluid out of the tubules and create a negative pressure on the nerve of the tooth, resulting in a sensitive sensation.

A hot stimulus will cause fluid in the tubules to move inwards, putting pressure on the nerve and causing the painful response.

Treating Sensitivity

Blocking the ends of the tubules can stop the sensitivity by preventing the movement of fluid in the tubules.  This can be achieved in a number of ways:

1.        Covering the tubules with a filling.

2.        Sealing the ends of the tubules with crystals of some kind.  These crystals could be chloride, calcium, phosphate or nitrate.

3.        Sealing the ends of the tubules with varnish.

4.        The use of topical fluoride solutions.

Dentists are able to perform any and each of these treatments.  The results are almost instant relief of sensitivity.  The effect will vary in its totality and in the time that it lasts.  This kind of treatment is usually relatively inexpensive, and quickly applied.

There is a simple way to treat the problem at home.  The use of sensitive toothpastes (Sensodyne, Colgate sensitive, Cedel) will all help.  They must be used regularly and for long periods.  This is because the actual desensitizing agent is only on the tooth for a relatively short period of time, while the teeth are being brushed.  These products work far better if the toothpaste is smeared onto the sensitive area at bedtime after regular brushing and rinsing of the mouth.  Leaving the product in contact with the teeth for 20 minutes or so, until the saliva naturally washes the teeth clean, will produce more rapid and more profound desensitization.

People with sensitive teeth should feel free to discuss their problem with a dentist. The tide of hypersensitivity can be stopped, enabling a pain-free lifestyle