Sensitivity

What is sensitivity?

Sensitivity is a sharp pain on a tooth usually caused by introducing something hot, cold or sweet. It occurs when there is loss of enamel, the tooth’s protective covering. Dentine which is the layer below enamel has nerves in it that cause sensitivity when exposed.

Who is at risk?

Sensitivity usually occurs when dentine is exposed due to dental caries (tooth decay) or mechanical or chemical enamel loss.
Mechanical loss can either be due to tooth fracture, attrition or abrasion. Attrition is when the opposing tooth causes wearing away of the enamel for example in people who grind their teeth. Abrasion is often caused by using a very hard toothbrush or using too much force when brushing.
Chemical enamel loss is common in people who drink a lot of acidic drinks and in people who have a condition that causes them to vomit frequently or have acid reflux.

Signs and symptoms

A sign of sensitivity is when a sharp pain occurs when the tooth comes in contact with heat, cold or sweet food. It usually subsides on its own after some time when the noxious agent is removed.

Diagnosis

A dentist can diagnose sensitivity by taking a history of the condition and examining. Usually the dentist will carry out simple tests on the chairside to confirm the diagnosis.

Prevention

Since decay can cause sensitivity, any measures to prevent decay would be beneficial.
Sensitivity caused by abrasion can be prevented by using a soft or medium strength toothbrush. The correct method of brushing is in small circular motion as opposed to horizontal back and forth movements. This prevents mechanical loss of enamel.
Tooth attrition can be prevented by using a mouth guard in cases of tooth grinding. Sometimes attrition is caused by teeth growing out of line and for this the dentist will recommend treatment modalities.
Also minimizing acidic food and drink can be preventative. For people with frequent vomiting or acid reflux, treatment of the condition and frequent use of fluoride tooth paste can prevent sensitivity.

Treatment

Your dentist could treat your sensitivity by applying topical fluoride or a fluoride varnish to the affected areas or on all teeth. This should be kept on for as long as possible to allow the teeth to absorb the fluoride.
Alternatively, if there is an obvious defect in the enamel for example in a fracture or if one was caused by abrasion, a filling might be necessary.