It's common for hot and cold foods to trigger tooth sensitivity, but if you have pain along with other symptoms – such as loose teeth, swollen gums or pain while chewing – you may have extremely sensitive teeth caused by another dental issue. Your dentist can determine the problem and appropriate treatment, but it's best to know what you're doing yourself to cause this oral issue.
What Is Tooth Sensitivity?
The crowns, or the part of the teeth above your gumline, are covered with a layer of protective enamel, while the roots below your gumline are protected with a material called cementum. Underneath the enamel and cementum is dentine, which is less dense than the protective coverings. The dentine contains microscopic canals called dentine tubules, and when enamel or cementum wears away or becomes damaged, it exposes the dentine. The Indian Dental Association notes that tooth sensitivity occurs when the underlying layer of your teeth - the dentine, becomes exposed as a result of receding gum tissue (the protective blanket that covers the tooth roots). The roots, which are not covered by hard enamel, contain thousands of tiny tubules leading to the tooth's nerve centre (the pulp). These dentinal tubules (or channels) allow the stimuli - for example: hot, cold or sweet food - to reach the nerve in tooth, which results in pain.
What Causes It?
Why would the enamel or cementum wear away? You may be consuming too many acidic foods and beverages, brushing your teeth too aggressively, or overusing certain tooth-whitening products. However, with extremely sensitive teeth, or hypersensitivity, the more likely causes are those that expose more dentine, such as tooth decay, worn fillings or fractured teeth.
Because extremely sensitive teeth are frequently caused by a more complex dental problem, it's important to see a dentist and have the issue treated directly. This may involve a crown, inlay or bonding, depending on the problem. If you have gum disease that has progressed to a chronic or advanced stage, you'll need to treat this as well.
If you have lost gum tissue from the root, your dentist may recommend a surgical gum graft to cover the roots so they're protected again. If you have persistent and severe sensitivity, an x-ray should be taken to determine if a root canal could be the issue, which, according to the American Association of Endodontists (AAE), removes the nerve so it's no longer there to cause you pain.
You can also find some relief from a desensitising toothpaste. Your dentist might also recommend a fluoride gel treatment, which strengthens your current tooth enamel, decreasing the sensations sent to the nerve.