It is not uncommon to have one or more teeth that are particularly sensitive to heat, cold, or pressure. If you have such a tooth, you probably want to know what caused it and what you can do about it. Here are some frequently asked questions, and their answers.

What causes teeth to become sensitive?
The most common cause of sensitivity is exposure of the tooth's dentin, a layer of the tooth's structure that is just below the outer protective layer (the enamel).

The dentin is sensitive but the enamel layer is not. Why?
The enamel is composed of minerals that are hard and protective. It is not living tissue and has no nerve supply. The dentin layer underneath is bone-like living tissue that does contain nerve fibers. It is protected by enamel above the gum line and by gum tissue in the area of the tooth's root, below the gum line. If the tooth's protective covering is reduced, the nerve fibers in that section of the dentin are exposed to changes in temperature and pressure, which they conduct to the inner pulp layer (nerve) of the tooth. The sensations that reach the tooth's interior pulp layer cause pain.

What causes exposure of the dentin layer in teeth?
Often the dentin is exposed by receding gums, causing areas of the tooth that are normally below the gum surface to be uncovered.

What makes gums recede?
One cause of receding gums is excessive, rough brushing techniques. This is particularly common in individuals who have a family history of thin gum tissues. Removing the film of bacteria called plaque requires only gentle action with a soft brush. This is one reason that we stress the value of learning proper and effective brushing techniques. Gum recession becomes worse after the uncovered dentin of the tooth's root is exposed to erosion from sweet and acidic foods and beverages, such as fruit juices.

Doesn't tooth sensitivity indicate decay?
Decay can also cause tooth sensitivity. As decay destroys a tooth's structure, it eventually invades the inner pulp of the tooth, causing greater and greater pain.

How can you prevent or reduce tooth sensitivity?
As we mentioned above, learn proper brushing techniques; we would be happy to demonstrate them. Use a toothpaste that contains fluoride, which increases the strength of the tooth's protective coating. In more serious cases, we can apply a fluoride varnish or a filling material as a barrier to cover sensitive areas. If you experience long-term tooth sensitivity, make an appointment for an assessment and diagnosis so that we can determine the cause and proper treatment.

Contact us today to schedule an appointment to discuss your questions about sensitive teeth. You can also read the Dear Doctor magazine article “Sensitive Teeth.”