Tooth sensitivity occurs when the enamel that protects teeth gets thinner, or when gum recession occurs, thus reducing the protection the enamel and gums provide to the tooth and root.
If this is the case, your tooth or teeth may feel sensitive or painful whenever you eat or drink hot, cold, sweet or very acidic foods or even when breathing in cold air.
Tooth sensitivity can come and go over time.
Origin of tooth sensitivity
In a healthy situation, the inside of a tooth is primarily made up of an organic material called dentin that protects the pulp (or the tooth's nerve) located in the middle. A hard outer layer of enamel protects the dentin within the crown portion of the tooth, while the dentin extending down to the root of the tooth is protected by a layer of cementum.
While enamel is the hardest and most highly mineralized substance of the body and (when intact) offers very good protection, the principal role of cementum is to serve as a medium by which the periodontal ligaments can attach to the tooth for stability.
Dentin has microscopic channels, called dentinal tubules, filled with tiny nerve endings, which radiate outward through the dentin from the pulp cavity to the exterior cementum or enamel border.
!!!Tooth sensitivity, also known as dentin hypersensitivity, occurs whenever dentin loses its protective covering of enamel or cementum, exposing the nerve endings to hot, cold, acidic or sweet foods.
What causes sensitive teeth ?
Tooth sensitivity can be caused by many types of dental issues:
Dental issues that can cause loss of enamel
- Aggressive tooth brushing, brushing too frequently, too vigorously or with a hard-bristled toothbrush can eventually wear down tooth enamel, particularly where the teeth meet the gums (where the enamel layer is thinner).
- Dental erosion is the loss of tooth enamel caused by acid attack. The most common cause of erosion is due to acidic foods and drinks: fruit juices, sports drinks, wine, beer, colas or lemonades.
- Teeth grinding, especially at night is a habit which involves clenching and grinding the teeth together. This can cause the enamel of the teeth to be worn away.
- A cracked tooth or a broken filling can also expose the dentin of your tooth.
Dental issues that can leave part of the tooth's root exposed
- A receding gum can expose both the dentin and the cementum creating sensitive areas on the surface of a root.
- Gingivitis or gum disease can weaken the gum tissue and cause the gum to recede down due to the build-up of plaque or tartar. Periodontal pockets can eventually form in the gums around the tooth, making the area difficult to keep clean and the problem worse.
- Some dental treatments such as crowns or fillings can cause a temporary dental sensitivity, but this usually goes away in some days or weeks.
- Some patients have sensitivity for a short time during bleaching or afterwards. You should discuss this with your dentist before starting the treatment.
How can I prevent sensitive teeth ?
There are many things you can do to prevent teeth sensitivity or sensitive teeth from recurring. Most of these measures do not apply just for preventing sensitive teeth, but for the health of your entire dental system.
Brush your teeth twice a day with a toothpaste that does not have high levels of abrasives. This can reduce the chance of tooth sensitivity and prevent gum diseases (more about proper tooth brushing technique).
Be sure to replace your toothbrush when it begins to show wear or at least every two months. A worn toothbrush can contribute to both gum recession and loss of tooth enamel.
Use a soft-bristled toothbrush and brush gently and carefully around the gum line so you don't remove gum tissue. Overaggressive tooth brushing can wear away the enamel and/or abrade the gums causing recession.
Use a fluoride toothpaste that can protect the enamel and root surface of your teeth.
Reduce highly acidic foods and drinks from your diet and try to keep them to mealtimes. These can wear away the tooth enamel and cause tooth erosion.
Wait for at least one hour after eating or drinking anything acidic before brushing your teeth. Acidic foods and drinks can soften the enamel of your teeth; waiting at leat an hour before brushing will give your teeth a chance to build up their mineral content and prevent brushing away the soft enamel.
If you grind your teeth, talk to your dental team about whether you should have a mouthguard made, to wear at night. Remember, teeth grinding can cause many dental problems.
If you are thinking about having your teeth bleached, discuss sensitivity with your dental team before starting treatment. Sometimes, you may have to use a sensitive toothpaste for two weeks prior to the whitening treatment.
How to treat sensitive teeth
If you are experiencing teeth sensitivity, start by visiting your dentist. Tooth sensitivity is typically the result of worn tooth enamel or exposed tooth roots. However, in some cases, tooth discomfort can be caused by other factors (such as a cavity, a cracked or chipped tooth etc.).
Your dentist can identify or rule out any underlying causes of your tooth pain.
Sometimes, treatment may be as simple as fixing a cavity or replacing a worn filling. Your dentist may also show you more effective tooth brushing methods.
Treatment approach may vary depending on the circumstances:
Toothpaste for sensitive teeth
There are several brands of desensitizing toothpastes to choose from. You should use them regularly; after several applications, it should make your teeth less sensitive.
Your dentist may also instruct you to spread a thin layer on your exposed tooth roots with your finger or a cotton swab before you go to bed.
Fluoride gels, rinses or varnishes can be painted onto sensitive teeth at regular practice-appointments. The use of fluoride may help strengthen tooth enamel and reduce pain. However, sensitivity can take some time to settle, and you may need to have several appointments.
Your dentist might also suggest the use of prescription fluoride at home.
When fluoride does not help, exposed root surfaces can be treated by applying bonding resins to cover exposed dentin. Bonding resins are usually applied around the neck of the tooth and light-cured.
If your discomfort comes from gum loss exposing root surfaces, your dentist may suggest a gum graft.
A gum graft is a relatively simple surgical procedure which aims to cover an area of exposed tooth root surface with grafted oral tissue. This can protect exposed roots and reduce sensitivity.
an example of gum graft to cover
an area of exposed tooth root
If your sensitive teeth cause severe pain and other treatments aren't effective, your dentist might recommend a root canal.
Last review and update: February 2019