Tooth sensitivity may occur when dentin, the layer of the tooth underneath the enamel, becomes exposed. This may occur through loss of tooth enamel , the outer covering of the tooth. For example, brushing the teeth and gum line too hard or using a hard-bristled toothbrush may wear away tooth enamel. In addition, enamel erosion, the loss of tooth structure, may occur as a result of consuming acidic foods. Tooth sensitivity may also occur as a result of gum recession and loss of the underlying cementum, which exposes the root surface. When dentin is exposed to an external stimulus, such as heat or cold, pressure or sweet and sour foods and drinks, a person may feel discomfort and sometimes a sharp pain in the tooth or teeth.
There are several conditions that give rise to pain, but that are not tooth sensitivity:
There are microscopic tubular structures in the dentin that radiate outward from the pulp of the tooth, which provides the tooth with blood and nutrients, to the external surface of the dentin. These tubules also connect the nerve fibers within the pulp. When dentin tubules are exposed and they experience an external stimulus, such as heat, cold, a change in pressure, or sweet or sour foods and drinks, the stimulus creates a change in dentin fluid flow, which is transmitted to the nerve fibers. When this occurs, the brain perceives this sensation as pain.
Talk to your dentist if you think you have tooth sensitivity so that he or she can provide the correct diagnosis and recommend treatment options.
1. Fischer C, Fischer RG, Wennberg A: Prevalence and distribution of cervical dentine hypersensitivity in a population in Rio de Janiero, Brazil, J Dent 20:272, 1992