Top 10 Causes of Tooth Sensitivity and What Helps

How this list is ordered

The causes are listed roughly from the most common to the less common in everyday dental practice, based on how dental guidance describes them, but this is an editorial ordering and not a measured ranking, and the order will differ for different people. Each entry explains what the cause is, how the pain typically feels, what often helps and when to seek care. Sensitivity is a symptom, not a diagnosis, so more than one cause can be present at once, and the real cause can only be confirmed by a dentist. Nothing here replaces an examination, particularly if the pain is severe, lasts or wakes you at night.

What sensitivity is and why it happens

Under the hard enamel of a tooth lies dentine, which contains tiny tubes leading towards the nerve. When enamel wears away or the gum recedes, those tubes are exposed, and cold, heat, sweet or acidic food and even air can move fluid in them, causing a short sharp pain. The NHS describes sensitive teeth as common and often treatable, and says that the discomfort usually lasts only a few seconds. Pain that lingers for minutes, throbs, wakes you at night or comes with swelling points to a different problem, such as infection or a damaged nerve, and needs prompt dental attention.

1. Worn enamel from erosion and wear

Enamel is worn away by acid, from fizzy drinks, citrus, juices, vinegar and reflux, and by hard brushing and abrasive products. Once it thins, the dentine beneath is exposed, producing sharp pain with cold, sweet or acidic foods. The change is gradual and permanent, because enamel does not grow back, but it can be slowed and the symptoms eased. Desensitising toothpastes can reduce the pain over several weeks when used regularly, fluoride helps strengthen what remains, and a dentist can seal exposed areas. Cutting down on acidic drinks and brushing gently with a soft brush helps. Watch out for brushing immediately after acidic food, for abrasive whitening pastes, for frequent vomiting or reflux, which also needs medical advice, and for ignoring early signs.

2. Gum recession

When the gums pull back, they expose the root of the tooth, which has no enamel covering and is very sensitive. Recession can result from gum disease, brushing too hard, thin gum tissue, grinding, tooth position or past orthodontic treatment. It tends to appear as sensitivity near the gum line and teeth that look longer. Treatment depends on the cause: gentler brushing technique with a soft brush, treating gum disease, desensitising products and, in some cases, a gum graft or bonding. Recession does not reverse by itself. Watch out for scrubbing harder because the area is sore, for ignoring bleeding, for smoking, which worsens gum health, and for crooked teeth with thin gum, where an orthodontist and periodontist may need to work together.

3. Tooth decay

A cavity breaks through the enamel and allows hot, cold and sweet things to reach the dentine and nerve. Early decay may cause only mild sensitivity to sweet food, while larger cavities produce stronger or lingering pain and may keep you awake. Decay does not heal once a cavity has formed, and it needs a filling or other treatment. Early white spots can sometimes be reversed with fluoride and better cleaning. Delay allows decay to reach the nerve and may lead to root canal treatment or extraction. Watch out for pain with sweet foods, a visible hole or brown spot, a bad taste, swelling and pain that wakes you. Book a dental appointment promptly rather than waiting for the pain to settle.

4. Cracked or chipped tooth

A crack can let fluid move within the tooth and irritate the nerve, causing sharp pain on biting, especially when you release the bite, or a twinge with cold. Cracks can be hard to see and hard to find without a dentist's examination, and they can worsen if left. Treatment ranges from bonding or a filling to a crown, and a deeply cracked tooth may need root canal treatment or removal. Sensitive teeth that hurt on biting should be checked. Watch out for chewing ice or hard sweets, for grinding, for pain that comes and goes, and for sharp pain after a knock. Avoid biting on the tooth and book a dental appointment, and seek urgent care if the tooth is broken or painful.

5. Worn or leaking fillings

Fillings can crack, wear or pull away from the tooth over the years, leaving a gap where bacteria and fluid get in. This can cause sensitivity around the filling and new decay beneath it. Fillings do not last for ever, and dentists check them at routine appointments. Replacement or repair usually solves the problem. A new filling can also be slightly high or deep and cause sensitivity for a while; if it does not settle within a couple of weeks or you feel your bite is wrong, tell your dentist. Watch out for a rough edge, a broken piece, food catching around a filling, pain on biting and a dark line at the margin, and keep up regular check-ups.

6. Teeth grinding and clenching

Grinding wears enamel, can cause tiny cracks and strains the ligaments around the teeth, so teeth feel sore or sensitive, especially in the morning, and the jaw muscles may ache. Many people do not know they grind, and stress, poor sleep and some medicines can contribute. A dentist can look for wear and may recommend a custom night guard, stress management and avoiding chewing gum or hard foods. Over-the-counter guards vary in quality. Grinding can also affect braces and retainers. Watch out for jaw pain or headaches, flattened or chipped teeth, a partner who hears grinding, and clicking joints. Our guides on bruxism and the jaw joint explain the links to orthodontic care.

7. Whitening

Whitening gels pass through enamel, and sensitivity is the most common side effect. It usually appears as sharp twinges during or shortly after treatment and settles within a few days. Stronger gels, longer contact and teeth that already have exposed dentine or receding gums raise the risk. Taking breaks, using a desensitising toothpaste before and during treatment, shortening wear time and avoiding very hot or cold drinks can help. Supervised whitening reduces the risk because the dentist checks suitability and chooses the strength. Watch out for stopping if pain is sharp or lasts beyond a few days, for overuse, for imported gels stronger than UK limits, and for whitening teeth with untreated decay or cracks.

8. Recent dental work

Fillings, crowns, deep cleans and some other treatments irritate the tooth temporarily, so mild sensitivity to cold or biting for days to a few weeks afterwards is common. A scale and polish can expose areas where tartar covered the root. It usually settles by itself, and desensitising toothpaste can help. Tell your dentist if the pain is strong, gets worse, lingers, keeps you awake or your bite feels high, since adjustments are quick and effective. Watch out for sensitivity that develops weeks later, for pain with biting that does not settle, and for swelling. Following the aftercare advice, such as avoiding very hot or cold food on the treated side briefly, helps recovery.

9. Braces and pressure

Fixed braces and aligners move teeth by applying gentle pressure, and the ligaments around the teeth are sore for a day to several days after fitting or an adjustment. This soreness is different from the sharp zing of exposed dentine, though some people also notice cold sensitivity. Soft foods, cold drinks, wax over rubbing brackets and, if suitable, over-the-counter painkillers used as directed can help. Persistent or severe pain, a loose bracket, white marks or swelling should be reviewed. Our guides on braces pain management and teeth sensitivity with braces explain what is normal. Watch out for pain that does not ease after a few days, for gum swelling, and for sharp pain from a poking wire.

10. Sinus problems

The roots of the upper back teeth sit close to the sinuses, so a sinus infection or congestion can cause an ache in several upper teeth at once, often worse when bending forward and accompanied by a blocked nose, facial pressure or a cold. The teeth themselves are healthy, and the cause is the sinus. A GP or pharmacist can advise on treatment for the sinus. If the pain does not clear when the cold settles, or it affects one tooth only, a dentist should check. Watch out for facial swelling, fever, pain that persists after a cold, and treating the teeth without checking the sinuses. Our guide on the link between sinuses and orthodontics gives more detail.

What helps at home

Several measures often reduce everyday sensitivity. Use a toothpaste for sensitive teeth twice a day, spit and do not rinse straight after so the active ingredient stays on the teeth, and give it several weeks to work. Brush gently with a soft brush and avoid scrubbing at the gum line. Limit acidic food and drink and have them with meals. Use a fluoride mouthwash at a different time from brushing if your dentist suggests it. Avoid very hot and cold extremes while teeth are tender. Wear a night guard if you grind. If these do not help within a few weeks, a dentist can apply desensitising varnish or recommend treatment.

Preventing sensitivity

Prevention is mostly about protecting enamel and gums. Brush twice a day with fluoride toothpaste using a soft brush and light pressure, clean between the teeth daily so gum disease is less likely, limit acidic and sugary drinks and keep them to mealtimes, wait before brushing after acidic food, wear a night guard if you grind, and avoid using teeth as tools. See a dentist regularly so that early wear, recession or decay is found before it hurts. If you smoke, stopping helps gum health. If you have reflux or frequent vomiting, ask a doctor for advice, because stomach acid is a major cause of erosion.

Sensitivity with braces and aligners

People wearing braces often have both ordinary sensitivity and pressure soreness, and plaque around brackets raises the risk of decay and white marks that can make teeth sensitive. Keep cleaning thorough with fluoride toothpaste, interdental brushes and, if advised, a fluoride mouthwash at a different time of day. Use a desensitising toothpaste if your orthodontist agrees. Aligner wearers should clean trays and teeth carefully, because sugary drinks trapped under trays raise the risk of decay. Tell your orthodontist if sensitivity is sharp, lasts after the first days of a new stage or comes with swelling, because it may be a sign of decay, a cracked tooth or an issue with the plan.

Sensitivity in children and teenagers

Children can have sensitive teeth too, most often from decay, enamel that did not form fully, a recent knock or new permanent teeth settling in. Baby teeth have thinner enamel than adult teeth and decay quickly. Teenagers who drink a lot of fizzy or energy drinks, brush hard or whiten at home are at risk of erosion. Take a child with ongoing sensitivity to a dentist rather than treating it at home, because the cause may need a filling, a sealant or fluoride varnish. Desensitising products are not always suitable for young children, so ask first.

When to see a dentist urgently

Seek a dental appointment promptly if you have pain that lingers after hot or cold, pain that wakes you at night, pain when biting, a swollen gum or face, a bad taste or discharge, a broken tooth, or sensitivity that is getting worse or has not improved after a few weeks of home care. Call NHS 111 if you cannot reach a dentist, and seek emergency help for swelling that affects swallowing or breathing, a high temperature with facial swelling, or a significant injury. Sensitivity that comes with these signs is not something to treat at home.

Questions to ask your dentist about sensitivity

Useful questions include what is causing the sensitivity in your case, whether it affects one tooth or several, whether you need an X-ray, whether a filling, sealant or varnish would help, which toothpaste to use and for how long, whether you grind your teeth and need a night guard, and how soon to come back if it does not improve. Writing down when the pain happens, such as with cold, sweet or biting, helps the dentist to narrow down the cause.

Key takeaways

Tooth sensitivity is common and often caused by worn enamel or gum recession, but decay, cracks, old fillings, grinding, whitening, dental work, braces and even sinus problems can also be responsible. Desensitising toothpaste, gentle brushing and less acid help many people, while lingering, night-time or biting pain needs a dentist. This is general information, not personal medical advice, so see a dentist for a proper diagnosis.

Useful related pages

This guide is for general information only. It is not a diagnosis, treatment plan, or substitute for advice from a registered dentist or orthodontist.