What Causes Tooth Sensitivity?

Tooth sensitivity, also known as dentin hypersensitivity, causes tooth pain in response to heat, cold, air flow, or light touch. It is a common issue, affecting about 10-30% of the population.

Many dental conditions can cause tooth sensitivity, so it’s important to seek dental care if you’re feeling this type of pain in your teeth.

The crown of the tooth—the part above the gumline—has a hard outer shell, or enamel. The root below the gums also has a covering, called cementum. Below these layers is a less dense material perforated with microscopic tunnels known as microtubules.

When there is damage to the enamel or cementum, or severe gum erosion, external triggers pass through microtubules to reach nerves in the pulp (inner layer of the tooth) and the tooth root. As a result, you may experience pain in response to typically painless habits, like drinking coffee.

Anything that damages the enamel or cementum can cause tooth sensitivity. Common causes include:

• Tooth decay: With tooth decay, holes or areas of damage form on the enamel. This can expose the dentin (the layer of the tooth beneath enamel), leading to tooth sensitivity and pain.
• Enamel erosion: Over time, acids in foods and drinks can break down and wear away tooth enamel, causing symptoms.
• Enamel abfraction: Enamel abfraction is damage due to physical or mechanical force. It can cause visible grooves in the teeth.
• Gum recession: Aging, genetics, and advanced gum disease cause gum tissue to recede, exposing dentin and tooth roots, leading to tooth sensitivity.
• Worn restorations: Dental fillings, crowns, and restorations can also become damaged or worn over time, exposing dentin and raising the risk of tooth decay.
• Tooth fracture: Fractures (breaks), cracks, or chips in tooth enamel can also expose dentin, allowing heat, cold, or other triggers to reach the dentin.
• Recent dental treatments: The nerves in the root of teeth can become inflamed after dental fillings, crowns, or restorations. This should resolve within 4-6 weeks.
• Improper brushing: Improper tooth brushing can cause gum recession, leading to sensitivity. Brushing too hard, using a 90-degree angle (rather than a 45-degree angle), or having toothbrush bristles that are too large or small all contribute to this issue.
• Oral hygiene products: Some mouthwashes contain ingredients that raise acidity, leading to enamel erosion. At-home teeth whitening kits and toothpastes containing damaging ingredients also cause tooth sensitivity. 
• Acidic foods: Citrus, tomatoes, sodas, and other foods and drinks raise acidity in the mouth, which can cause tooth erosion.

Many factors can contribute to tooth sensitivity and raise your risk of developing this issue. These include dental conditions as well as oral health and hygiene practices.

Cavities

Cavities are areas where enamel breaks down due to tooth decay, causing fissures (cracks) and eventually holes in the tooth. Often painless in early stages, more severe cavities cause tooth sensitivity when they expose dentin.

Gum Disease

As mild gum disease, known as gingivitis, progresses to advanced gum disease, known as periodontitis, gums become inflamed and pull away from the teeth. This loosens the ligaments that support the teeth, which can expose dentin and tooth roots.

Bruxism

Bruxism occurs when you grind or clench your teeth too much. The repeated stress and strain on the enamel can cause enamel abfraction, or the wearing down of enamel. This raises the risk of tooth sensitivity.

Age

As you age, your enamel changes structure and gets thinner, which raises the risk of tooth decay, enamel erosion, and other issues. Your gums can also recede with age, causing teeth to appear longer and exposing roots, leading to tooth sensitivity.

Plaque and Tartar Buildup

If you don’t brush and floss daily, plaque—a sticky film of bacteria—forms on your teeth. Over time, it develops into tartar, a hardened, crust-like deposit along the gum line or on the backs of teeth. Plaque and tartar cause gum disease and raise the risk of tooth decay.

Dry Mouth

Saliva protects teeth from plaque buildup and neutralizes mouth acidity. Xerostomia (dry mouth), or a lack of saliva, raises the risk of tooth decay, gum disease, and other risk factors for tooth sensitivity.

Dry mouth is a common side effect of many medications and radiation therapy. It’s also a symptom of Sjögren’s syndrome, an autoimmune disease affecting the salivary glands.

Smoking

Along with other negative health effects, smoking or chewing tobacco increases your risk for tooth decay, tooth loss, gum disease, and other dental issues that cause tooth sensitivity. Smoking also stains teeth and causes dry mouth, leading to plaque and tartar buildup.

GERD

Gastroesophageal reflux disease (GERD) causes constant heartburn as stomach acid flows up the esophagus. If the acid reaches the throat and mouth, it can cause dental erosion, raising the risk of tooth sensitivity.

In general, you should see a dentist if you have tooth sensitivity that doesn’t go away. Stabs of pain when breathing in, eating spicy or sweet foods, drinking hot or cold drinks, or brushing or flossing are all signs to call your dentist.

When you have tooth pain, dentists work to identify the underlying cause of this symptom. They also rule out other potential causes of pain, such as tooth infection. This typically involves several steps:

• Medical status and history: Your dentist will ask about your current health conditions and past dental procedures. This helps them identify medical factors that may be at the root of symptoms, such as medications or diseases that raise risk, like diabetes.
• Clinical exam: The dentist will examine your teeth using specialized probes and other tools, looking for signs of cavities or damage. They may use air blasts or a cold stimulus (cold water, ice) to see how you respond.
• Gum exam: Dentists use a tiny ruler called a probe to see how deep the “pockets” between the teeth and gums are; larger pockets and inflamed gums are signs of gum disease.
• X-ray: Dental X-rays help dentists assess the thickness of enamel and the scope of damage caused by cavities, fractures, or other dental issues.

Since tooth sensitivity can be a sign of an issue that worsens without treatment, like gum disease or tooth decay, it’s critical to seek care. The sooner your dentist diagnoses the problem, the sooner they can treat it, preventing complications and improving outcomes.

Management approaches for tooth sensitivity depend on the underlying cause. Common treatments include both home remedies and in-office procedures.

Home Remedies

Your dentist may recommend a few tips and over-the-counter (OTC) products you can try to reduce sensitivity, such as:

• Desensitizing toothpaste: Toothpastes like Sensodyne contain ingredients that block nerve activity in the teeth, as well as fluoride, which strengthens them. Over time, using these toothpastes helps reduce symptoms.
• Fluoride mouth rinse: Mouthwash that contains fluoride and desensitizing agents can help strengthen tooth enamel and reduce tooth sensitivity.
• Salt water rinse: Gargling with a solution of salt and warm water eases swelling and inflammation in the gums, helping with pain.

Dental Procedures

In addition to home care, you may need in-office treatment to address any underlying causes of your tooth sensitivity:

• Fluoride treatment: In the office, dentists apply fluoride gel, veneers (front covers of teeth), or other adhesives to strengthen enamel. 
• Dentin sealing: If you have exposed dentin, dentists apply specialized materials, often resin, to seal off the microtubules.
• Root canal: In severe cases, the dentist removes the nerve at the root of the tooth, which stops all pain sensation.
• Gum surgery: For severe gum recession or exposed tooth root, surgeons harvest tissue from another part of the mouth and graft it to the affected areas.

The best way to prevent tooth sensitivity is to practice good oral hygiene and dental health practices. Steps to take include:

• Brush twice daily: Brush at least twice a day, using proper technique. Holding your brush at a 45-degree angle, make gentle, circular motions across your teeth, getting each tooth. Too much or too heavy brushing can cause tooth sensitivity, so talk to your dentist about best practices. You can also choose a toothbrush made for sensitive teeth, such as one with soft bristles or an electric toothbrush with a pressure sensor.
• Floss daily: Since flossing is the only way to remove food and plaque between teeth, you should floss at least once a day.
• Get regular dental checkups: Dental checkups and cleanings allow dentists to identify potential causes of tooth pain and remove tartar. Aim to have routine exams every six months. 
• Stay hydrated: Drinking water helps prevent dry mouth, restore acid balance, and aid saliva in clearing away food debris and bacteria.
• Avoid smoking: Avoiding smoking reduces your risk of gum disease, tooth decay, dry mouth, and other contributors to tooth sensitivity.
• Limit sugary and acidic drinks: Sodas, juices (especially citrus), tea, coffee, and sugary drinks can raise acidity in the mouth and promote plaque and tartar formation.
• Make necessary dietary changes: Reducing your intake of acidic foods, like oranges or citrus, can help prevent enamel erosion and tooth sensitivity.

Tooth sensitivity refers to a shooting pain that occurs when teeth are exposed to external stimuli like hot or cold temperatures, air flow, or touch. It happens when dentin or tooth roots are exposed.

Tooth erosion, damage, and mechanical wear and tear can all cause tooth sensitivity. Because it can be a sign of underlying dental conditions, call your dentist if you have tooth sensitivity that doesn’t go away.