Sensitive Teeth

Having sensitive teeth generally means that you have some type of pain or discomfort in our teeth. This discomfort can result from eating or drinking something cold, hot or sweet. There are two main types of sensitive teeth. One of the types is when the dentin of your tooth is bare. Here are some things that will let you know if you have sensitive teeth:

  • Drinking or eating hot things
  • Eating sweets
  • Touching the teeth with other teeth or the tongue

Dental sensitivity occurs when the dentin (middle layer) of a tooth is exposed. Normally, the dentin is covered by enamel above the gum line and by cementum below the gum line. Dentin is made up of tiny openings called tubules. Inside each tubule lies a nerve branch that comes from the tooth’s pulp (the nerve center of the tooth). When the dentin is exposed, cold or hot temperature or pressure can affect these nerve branches. This causes sensitivity.

Dentinal sensitivity occurs when the outer protective layers of enamel are removed, exposing the dentin in one or more teeth. Some causes of dentin exposure include brushing your teeth too hard. Brushing your teeth too hard can wear the enamel of your teeth away. Having poor oral hygiene can increase your chances of getting sensitive teeth. This may allow tartar to build up at the gum line. Long-term tooth wear. Untreated cavities, an old filling with a crack or leak, receding gums that expose the tooth’s roots, and receding gums often are caused by periodontal diseases or by brushing too hard. Gum surgery that exposes a tooth’s roots. Tooth whitening in people who have tooth roots that already are exposed. Frequently eating acidic foods or drinking acidic beverages. Pulpal sensitivity is a reaction of the tooth’s pulp. The pulp is a mass of blood vessels and nerves in the center of each tooth. Pulpal sensitivity tends to affect only a single tooth.

Causes include:

  • Decay or infection
  • A recent filling
  • Excessive pressure from clenching or grinding
  • A cracked or broken tooth
  • If you feel a sharp pain upon biting, you may have a broken or cracked filling.
  • Pain when you release a bite is a sign of a cracked tooth.


Both dentinal and pulpal sensitivity usually involve reactions to temperature or pressure. Sensitivity to cold drinks or foods is the most common symptom. Less often, the teeth are sensitive to hot temperatures. If a single tooth becomes sensitive to heat, the tooth’s nerve may be dying. In this case, root canal treatment is necessary.

How to Check

Your dentist will look at your dental history and will examine your mouth. You also will need X-rays to show if there is decay or a problem with the nerve. He or she will ask about your oral habits. Grinding or clenching your teeth can contribute to sensitivity. Your dentist also will look for decay, deep fillings and exposed root surfaces. He or she may use an explorer — a metal instrument with a sharp point— to test teeth for sensitivity.

A tooth may be sensitive to cold for several weeks after a filling is placed. The metals in amalgam (silver) conduct the cold very well, transmitting it to the pulp. Bonded (tooth-colored) fillings require etching the tooth with acid before the filling is placed. In some cases, this etching removes enough enamel to make the tooth sensitive. However, advances in bonding now make it less likely to cause tooth sensitivity. Your dentist can conduct tests to see if you need root canal treatment.

How to Prevent Sensitive Teeth

You might be able to reduce your chances of dentinal sensitivity by:

  • Brushing twice a day and flossing daily
  • Using a soft or ultra-soft toothbrush and brushing gently up and down, rather than side to side
  • Using a fluoride toothpaste and mouth rinse
  • Using a toothpaste that provides protection against sensitivity
  • Getting treatment for grinding or clenching your teeth


Dentinal sensitivity is quite treatable, whatever the cause. Your dentist or dental hygienist will clean your teeth. If your teeth are too sensitive to be cleaned, your dentist may use a local anesthetic or nitrous oxide before the cleaning.

After a cleaning, your dentist may apply a fluoride varnish to protect your teeth. This temporarily reduces sensitivity. It also strengthens your teeth. Your dentist may apply an in-office treatment for sensitivity. These products block the openings (tubules) in your teeth and reduce sensitivity. A newer approach is to use a dental laser. The laser treatment also alters the tubules to reduce sensitivity.