It will help to be familiar with Soft Tissue Grafting prior to reading this section.

Root Sensitivity, or dentinal hypersensitivity, is a result of exposed dentin following recession or abfraction (tooth wear).  Dentin, or the tooth layer that is closest to the pulp, has fluid filled tubules that respond to changes in temperature, air pressure, sweets, sour, or force.  While these dentinal tubules are typically insulted by enamel and cementum (root surface), they sometimes are exposed and subject to more pronounced changes.  This change in hydrodynamic equilibrium results in a nerve stimulation that sends signals to the brain.  Unfortunately, the only signal a tooth can send is pain.  

Typically, treatment for root sensitivity includes soft tissue grafting and/or over-the-counter medicaments such as Sensodyne.  In some cases, in-office products can also be used and in some severe unresolved cases, it may be necessary to perform root canal therapy.

If you have root sensitivity, it is important to contact your dentist or periodontist to have it evaluated, as it could be a sign of periodontal disease, endodontic problems, root fracture, or abscess.