For people with tooth sensitivity, eating or consuming certain substances or substances at certain temperatures causes discomfort or pain in their teeth. At least 40 million adults suffer from sensitive teeth in the United States, according to the Academy of General Dentistry.
The pain is often sharp and sudden, but it is transient. Tooth pain occurs when stimuli, such as hot and cold, reach the exposed nerve endings of a tooth, according to Cleveland Clinic. Fortunately, sensitive teeth can be treated and the condition can be improved.
Causes of tooth sensitivity
There are no risk groups for tooth sensitivity. It can happen to anyone, according to Dr. Margaret Culotta-Norton, a Washington D.C. dentist and past president of the DC Dental Society.
“The most common symptom … is a sudden, sharp flash of pain when the teeth are exposed to air, cold, sweet, acidic or hot food,” Culotta-Norton told Live Science. Some people may also experience tooth sensitivity from brushing or flossing their teeth.
Tooth sensitivity generally results from the exposure of a layer of the tooth called dentin. The outside of each tooth is usually covered by a hard outer layer, called enamel or cementum, which protects this dentin – the softer, inner layer of the tooth. Enamel protects the crown, the part of the tooth that is visible above the gums. Cementum covers the dentin surrounding the root, the pointed part of the tooth that extends into the jawbone, according to American Dental Association. The gum also protects the root. If the enamel or cementum wears away or if the gum line has receded, then the dentin is exposed. “Caries, cracked teeth, gum recession, enamel and root erosion all cause dentin to be exposed,” Culotta-Norton said. “Dentin connects to the nerve that causes pain in sensitive teeth.”
Dentin contains thousands of tiny tubules, or canals, that lead to the pulp of the tooth, according to Academy of General Dentistry. When exposed, these dental tubules allow heat, cold or acidic substances to reach the nerves inside the tooth, causing pain, according to the Cleveland Clinic. Pain is the only type of response that nerves inside teeth have, Live Science previously reported.
According to the Cleveland Clinic, some factors that contribute to sensitive teeth may include:
- Brushing too hard or using a toothbrush with hard bristles. This can wear down the enamel, causing the dentin to be exposed, or encourage gum recession.
- Receding gums. This often happens in people suffering from gingivitis, including gingivitis. Gum recession exposes dentin.
- Cracked teeth. The cracks can fill with bacteria from the plaque and cause inflammation in the tooth pulp. In more severe cases, it can lead to an abscess and infection.
- Grinding or clenching of teeth. This can wear down the enamel.
- Plaque build-up.
- Long-term use of oral solution. Some over-the-counter mouthwashes contain acids. If the dentin is exposed, the acids can exacerbate existing tooth sensitivity and further damage the dentin layer. There are neutral fluoride mouthwashes available that may be a better choice.
- Acidic foods. These can encourage enamel reduction.
- Dental procedures. Teeth can be sensitive after professional cleaning, root planing, crown replacement and other procedures. Usually the pain will go away in four to six weeks.
Tooth sensitivity after filing
Some people may experience tooth sensitivity after having a cavity filled, according to the Cleveland Clinic. Fortunately, tooth sensitivity after a filling should improve on its own within a few weeks.
Sometimes teeth become sensitive when biting after a filling. This can happen because the filling is too high and prevents your bottom and top teeth from fitting together properly. In this case, the dentist may need to reshape the seal. If you get a metal filling and it touches another type of metal, such as a gold or silver crown, when you bite down, the contact between the two different metals may cause some pain at first, but it should subside.
If you have toothache-like pain after a filling that doesn’t go away, the inside of the tooth, called the pulp, may be severely inflamed. This inflammation is called pulpitis, according to the Merck Manual. If the inflammation is so severe that the pulp becomes necrotic or begins to die, a root canal may be needed, in which the damaged tissue is replaced with a filling of a rubber-like substance called gutta-percha or another material, according to Academy of General Dentistry.
Tooth sensitivity after whitening treatments
Teeth whitening treatments — done either at the dentist’s office or using an over-the-counter product — contain harsh chemicals (hydrogen peroxide or carbamide peroxide) that remove stains, but they can also cause tooth sensitivity. When the peroxide penetrates the enamel, it can temporarily irritate the tooth. Excessive use of bleach can also damage enamel and gums, according to the American Dental Association.
Several studies have investigated ways to reduce pain after teeth whitening treatments performed by the dentist. A 2018 study in the journal Surgical Dentistry found that patients given acetaminophen/codeine before treatment did not reduce pain. A 2016 study in the journal Lasers in Medical Science found that irradiating teeth with a low-level laser after whitening treatment significantly reduced pain levels compared to patients who did not receive laser treatment. And a 2018 study published in The Journal of the American Dental Association found that application of a desensitizing gel prior to whitening significantly reduced tooth sensitivity after treatment.
Another possible solution is to change the formula of the whitening products. A 2017 study published in the journal Clinical Oral Investigations found that reducing the acidity in whitening gels resulted in significantly less pain with the same whitening results.
Treatment of tooth sensitivity
“Sensitive teeth never go away completely,” Culotta-Norton said. “Symptoms may be less or even seem to go away for a while, but unless the reasons why a person’s teeth become sensitive are not completely addressed, the sensitivity will come and go.”
There are several types of treatment available, and each dentist has his or her favorites that they are most likely to recommend, according to Culotta-Norton. He emphasized that there is no single treatment option that works for everyone. “Correctly diagnosing the cause of sensitivity is essential to treating sensitivity. If the reason for the sensitivity is addressed, the treatment chosen will be more successful in reducing pain. If the dentist simply treats the sensitivity without addressing the reason for it sensitivity, the problem will continue and get worse,” he said.
Here are some home remedies recommended by Cleveland Clinic:
- Desensitizing toothpaste. There are several brands of toothpaste for sensitive teeth available. Your dentist may recommend one, or you may need to try different brands until you find the product that works for you. Make sure you use fluoride toothpaste for sensitive teeth, not tartar control toothpaste. Try applying a thin layer of desensitizing toothpaste to exposed tooth roots before bed.
- Use a toothbrush with soft bristles.
- Avoid foods with a high acid content.
- Use a fluoride mouthwash daily.
- Avoid teeth grinding. Consider getting a mouth guard.
Here are some dental procedures that may reduce tooth sensitivity, according to the American Dental Association:
- Welding, crowns or inlays. These can correct a tooth defect or decay that is causing sensitivity.
- Fluoride gel.
- Surgical gum grafting. This will protect the root and reduce sensitivity if the gum tissue has eroded away from the root.
- Root canal. This is a last resort treatment for severe tooth sensitivity that has not been helped by other methods.
Fluoride treatment for sensitive teeth
A review article published in 2015 in the journal Dental caries research suggests that fluoride alone cannot prevent tooth decay, which can lead to tooth sensitivity. The authors suggest that treatments combining fluoride with polyvalent metal ions and certain polymers may offer more protection. The authors said more studies are needed to determine the effectiveness of these additives.
In 2014, the FDA approved the use of silver diamine fluoride (SDF) to treat tooth sensitivity, according to Association of State and Territory Dental Directors (ASTDD), a national nonprofit oral health organization. The topical treatment has long been popular in Asia and Europe and is used to prevent pain and tooth decay. A 2011 short-term clinical trial in Peru published in Journal of Dental Research found that participants with tooth sensitivity who underwent topical SDF applications experienced significantly reduced levels of pain. The application of SDF results in a harder tooth surface, helping to prevent further tooth decay. It also protects exposed dentin from potentially painful stimuli by partially blocking the dentinal tubules, according to University of California, San Francisco Protocol on the use of SDF to treat caries, published in the Journal of the California Dental Association.
Silver diamine fluoride treatments must be administered by a dentist, according to the ASTDD. When applied to areas of deionized (damaged) enamel or dentin, silver diamine fluoride results in a permanent black stain on the tooth. However, it does not stain healthy teeth. Silver diamine fluoride treatments arose from the Japanese practice of tooth tanning, called ohaguro, in the 19th century, according to the journal Oral Science. People with silver allergies should not use this treatment.
This article was updated on May 18, 2021 by Live Science contributor Ashley P. Taylor.
