Does the thought of biting into an ice cream cone give you shivers? Do you relate to commercials for Sensodyne toothpaste better than you’d like?  You might be suffering from dentinal sensitivity or hypersensitive teeth.

The part of  your tooth that is above the gum line is called the crown of the tooth.  Generally this part of the tooth is covered by the hardest substance in the body…the enamel.  Underneath this enamel layer is the dentin.  Dentin is less hard than enamel and contains microscopic funnel shaped tubes that contain a water like fluid.  These tubes connect the nerve of the tooth (a.k.a “the pulp“) to the outer layer of the tooth.  If the enamel layer has been breeched or eroded away these tubes actually open into the mouth.  This is where we can run into problems.

Wait…it gets worse.  The root is the part of the tooth that is embedded in your jaw bone.  This is the part of the that you can’t see when you have normal healthy gums but you can start to see if you have recession.  The root has dentin too, but is covered in the much less durable cementum.  So once your gums start to recede the part of the tooth that is exposed is much more likely to wear away with normal eating and brushing.  

If the dentin is exposed through loss of enamel or gum recession the little tubes full of water are open to the mouth.  When this water moves in and out through the tubes, it causes the nerve of the tooth to fire off a painful signal.  

Water can move in these tubules due to:

  • dehydration (breathing in dry air, for instance)
  • temperature changes (eating ice cream, drinking coffee or taking a deep breath of mid-winter Michigan air) 
  • chemical changes from diet (sweet stuff like candy or acidic stuff like fruit juice)

Do you have dentinal sensitivity?  Would you like to know if anything can be done to help?  If so, stay tuned for “The story of sensitivity part II, the solution.”