Most people would have experienced a searing pain when gulping a cold drink or eating ice cream at one time or other.

Hot drinks can have the same painful effect when the beverage washes through the mouth and touches the teeth. These are the classic symptoms of sensitive teeth.

But what causes sensitive teeth?

1. Exposure of root structure

It could be that the root structure of one or more teeth is exposed. The dentin layer, which lies directly under the top layer, or enamel, has microscopic tubules, each of which is connected to a nerve ending.

If the gum recedes and the root is exposed with the tubules, it can lead to a sensitive tooth.

2. Erosion of enamel

Erosion of the enamel above the gum can also be a problem, leaving the dentin exposed and causing sensitivity.

In fact, dentin can be left unprotected by receding gums, brushing too hard, grinding the teeth as well as drinking too many acidic beverages.

3. Overaggressive brushing

Surprisingly, overaggressive brushing can create serious problems. Mark S Wolff, DDS, PhD, a professor and chair of the Department of Cariology and Comprehensive Care at NYU College of Dentistry says, “Harsh strokes wear away at the gum tissue as well as the tooth’s enamel layer, leaving each dentin tubule vulnerable to whatever it comes in contact with – hot, cold, soft or hard.”

4. Acidic beverages

Certain drinks can also have a nasty effect on the teeth. Any highly acidic beverage — such as soft drinks, sports drinks, alcohol, fruit juice, coffee and some healthy drink alternatives — can aggravate enamel erosion and cause soreness.

Though carbonated water is generally okay, care should be taken with flavoured seltzer water because it contains citric acid.

5. Tooth whitening agents

If used too often, tooth whitening agents, which contain high levels of harsh ingredients to remove stains, can irritate the dentin.

Unfortunately, tooth whitening agents can in some cases strip the enamel layer, causing the tubules to be left unprotected.

Consult a doctor if the sensitivity is serious for advice on bonding vulnerable areas. Your dentist may apply a “varnish” to the tooth, but it is not a lasting fix.

This article first appeared on Hello Doktor and was medically reviewed by the Hello Doktor Medical Panel. The Hello Health Group does not provide medical advice, diagnosis or treatment.