How SENSITIVE are you?

Many people experience a degree of tooth sensitivity.  Sensitivity can be caused by a variety of things. Tooth decay in the early stages can manifest itself as sensitivity before the tell tale sign of a throbbing ache. Therefore pain lasting more than a few seconds needs investigation by a dentist.


Usually tooth sensitivity (dentine hypersensitivity) presents as temporary tooth discomfort or pain after eating cold food, drinking cold liquids, or breathing cold air.


Dentine sensitivity is caused by

  1. Incorrect brushing or damage to the gums by the build up of plaque
  2. Grinding or clenching which causes small hairline cracks to develop in the enamel
  3. Enamel erosion by acids most commonly fizzy drinks and fruit juices or bulimia
  4. Bad habits such as nail biting which can damage the enamel


It is essential that teeth are brushed correctly. Over vigorous brushing of the gums can cause the gums to shrink down the tooth (gingival recession). It is important that too much force is not used. Toothbrushes should last 2 to 3 months if yours is wearing away/splaying quicker than this you may be brushing too hard. However poor oral hygiene leads to a build up of plaque which when left along the gum margins can cause gum disease. Again the gingival (gum) tissue migrates down the tooth root exposing dentine.


However enamel can become cracked or chipped due to grinding the teeth at night. The severe forces exerted upon the teeth causes the enamel to crack exposing the dentine beneath. Also grinding can make the nerve very responsive and therefore pain is detected more easily.


Acidic drinks like juices and carbonated drinks can thin and weaken the enamel over time especially in combination with mechanical erosion from tooth brushing this tends to happen on the front surface of the teeth and can usually be seen. Acid erosion due to excessive vomiting as seen with bulimia or caused by pregnancy dissolves the enamel on the inner surface of the teeth.


Treatment of sensitive teeth

Obviously it is important to try and remove the underlying causative factor but in most cases this isn’t possible or the damage has already occurred.  Sensitivity is caused by exposure of dentinal tubules to cold.  Dentine (the layer under enamel) is composed of microscopic fluid filled tubes which lead directly to the nerve. Cold stimulus is transmitted through the fluid causing the characteristic sharp pain.


Treatments involve covering over the exposed dentine. There are many treatments that are available over the counter. Some toothpastes contain potassium nitrate. This usually reduces sensitivity after a few weeks of use. Sometimes if the sensitivity is limited to one area the toothpaste can be rubbed on in a small amount in this specific place. Treating sensitivity with fluoride mouthwashes can also help.


Some toothpastes contain Strontium Chloride. These products pull minerals from saliva and encourage them to crystallize over the dentine tubules thereby blocking the tubule preventing the cold stimulus reaching the nerve.

Products available include:

  • GC MI Paste plus
  • Sensodyne toothpaste
  • GC ToothMousse
  • Arm and Hammer Enamel Care
  • Colgate sensitive multi protection
  • Premier Enamelon


The dentist can apply bonding agents to the tooth which cover the dentine and so also block the tubules and manufacture splints that reduce clenching and grinding.