Why Does My Tooth Hurt When I Bite Down?

A tooth that hurts when you bite down is telling you that something is wrong with the tooth, the filling or crown on it, or the gum and bone around it. The most common causes are a cracked tooth, decay, a filling that has come loose or sits too high, gum disease or infection, sinus pressure and grinding. Only a dentist can tell which it is, because several of these feel very similar.

The good news is that most of these problems are easier to treat the earlier they are seen. This guide explains what each cause tends to feel like, what you can do today to stay comfortable, what a dentist will check and the signs that mean you should get help the same day.

Key takeaways

• Pain when you bite is a sign to see a dentist. It rarely settles for good without help, even if it eases for a while.
• Common causes are a cracked tooth, decay, a high or loose filling, gum disease or abscess, sinus pressure and grinding.
• Pain that appears when you release the bite, or comes with heat and cold sensitivity, can point to a crack or a problem with the nerve of the tooth.
• Until you are seen, chew on the other side, eat soft food and use over the counter painkillers as the packet advises.
• Swelling of the face or neck, a high temperature or trouble breathing or swallowing are urgent signs. Do not wait for an appointment.

Why does a tooth hurt when you bite down?

When you bite, your teeth press down into the bone through a thin layer of tissue that holds each tooth in place. If a tooth is cracked, inflamed, infected or sitting too high, that pressure is felt as pain. The nerve inside the tooth and the tissue around its root are both sensitive to pressure.

According to the NHS, toothache that comes with pain when biting is a reason to see a dentist, and so are toothache lasting more than two days, pain that continues after painkillers, a high temperature, red gums, a bad taste in the mouth or a swollen cheek or jaw. Your GP cannot provide dental treatment, so go to a dentist.

Common causes of tooth pain when biting

Here is a quick overview, followed by more detail on each cause. The descriptions are general. Your own pain may not match them neatly, and a dentist needs to examine you to say what is going on.

A cracked tooth

Cracks can be tiny and invisible to the eye or an X ray, which is why they are tricky. A typical sign is a sharp pain when you bite on something, and sometimes the sharper pain comes when you let go. The tooth may also be sensitive to cold. Cracks can follow biting on something hard, a large old filling, or years of grinding.

The NHS lists a cracked or damaged tooth among the causes of toothache. A crack is not something to wait on, because it can deepen over time. If you have chipped or broken a tooth, our broken tooth emergency service explains what we can do.

Tooth decay

Decay starts without any symptoms. According to the NHS, as it advances a hole can form in the tooth, and signs include toothache and sensitivity to hot, cold or sweet food, as well as white, brown or black spots. Once the cavity is deep, biting can press food into it or put pressure on an inflamed nerve, which is when the pain appears. The NHS says a cavity usually needs a filling, and decay that reaches the pulp may need root canal treatment.

A loose, lost or high filling

A new filling or crown that sits slightly too high can make that tooth meet the opposite tooth first and feel sore on biting. An older filling can also crack or loosen, letting bacteria in underneath. The NHS lists a loose or broken filling among the causes of toothache. If a filling has come out, our service for a lost or broken filling explains how we can repair it.

If a filling feels high, do not file it down or try to adjust it yourself. A dentist can usually check the bite quickly and reshape it.

Gum disease or an abscess

Gum disease can loosen the support around a tooth, so biting becomes tender. A dental abscess is a collection of pus caused by infection. The NHS describes symptoms that include intense toothache, a bad taste, sensitivity to hot and cold, trouble opening the mouth or chewing, a swollen face and a high temperature, and says a dental abscess will not go away on its own. Our dental abscess service explains urgent care, and our gum disease treatment covers swollen or bleeding gums. We have a separate post on tooth abscesses and when they need urgent care.

Sinus pressure

The roots of the upper back teeth sit close to the sinuses, so a cold or sinus infection can make those teeth ache, and biting can feel worse. The NHS lists toothache among the other symptoms of sinusitis, with a blocked or runny nose and pain or tenderness around the cheeks, eyes or forehead. If several teeth on one side ache at once and you have a blocked nose, sinus pressure is possible, but a dentist should still rule out a tooth problem.

Grinding and clenching

Grinding puts heavy, repeated pressure on your teeth and can leave them tender, worn or cracked. The NHS lists teeth grinding as a cause of toothache and says it can lead to worn, broken or sensitive teeth and jaw pain. If your teeth feel sore mainly in the morning, grinding is worth raising at your appointment. Pain from the jaw joint can also be mistaken for a sore tooth, as we explain in TMJ pain and toothache.

What to do today if your tooth hurts when you bite

The aim is to stay comfortable and avoid making things worse until a dentist can see you. None of this treats the cause.

• Chew on the other side. Stick to soft foods such as pasta, soup or eggs, and avoid hard, chewy and sticky foods.
• Use over the counter painkillers. The NHS suggests painkillers from a pharmacy and advises asking a pharmacist if you are unsure. Follow the packet carefully and do not take more than the recommended amount.
• Rinse gently. The NHS suggests rinsing with warm salt water, using half a teaspoon of salt in a glass of water, then spitting it out.
• Keep cleaning your mouth. Use a soft toothbrush and avoid flossing right around the sore tooth.
• Skip very hot, cold or sweet food and drink, and avoid smoking.
• Do not wait it out. If the pain eases, the problem may still be there. A crack, decay or infection can quietly worsen.

If you are unsure whether it is urgent, our emergency appointment service offers same day slots, and the fee is listed at £99 on our fee list, which includes a prescription and periapical X rays.

What will a dentist check?

Your dentist will start by listening to what you feel and when. It helps to note whether the pain is sharp or dull, whether it comes on when you bite or when you release, whether hot and cold make it worse, and whether anything else has changed, such as a bad taste or swelling.

Then they will usually look at the tooth and surrounding gum, test how it reacts to pressure, temperature or tapping, and check how your teeth meet. X rays can show decay, bone changes and infection around the root, although a very fine crack may not show on one. A full dental examination includes X rays and a bite and jaw assessment, so it is a good way to look at the whole mouth rather than one tooth.

How is pain on biting treated?

Treatment depends on the cause, and every case differs. This is a general guide to what a dentist may suggest after examining you.

• Crack: a bonded repair, or a crown to hold a weakened tooth together. If a crack reaches the nerve, root canal treatment may be needed. Our dental crowns service explains how crowns protect a damaged tooth.
• Decay: a filling, or root canal treatment if the nerve is affected. Our root canal service lists pain on biting among the signs that may point to a tooth that needs it.
• High or loose filling: adjusting or replacing it.
• Gum disease: a deep clean and a plan for long term gum care.
• Abscess: draining the infection and treating the cause, which may be root canal treatment or removal of the tooth. According to the NHS, a dentist drains the pus, usually under local anaesthetic, and you may sometimes be given antibiotics.
• Sinus pressure: usually managed with your GP or pharmacist once the tooth is ruled out.
• Grinding: a night guard can protect your teeth from wear and ease strain, along with advice on stress and sleep.

Sometimes a tooth cannot be saved, for example when it is broken down too far or an infection keeps returning. Your dentist will explain the options and a written plan before any treatment starts.

When to get urgent help

Some signs mean you should not wait for a routine slot. According to the NHS, go to A&E if the area around your eye or your neck is swollen, or if swelling in your mouth or neck makes it difficult to breathe, swallow or speak. Do not drive yourself. Ask someone to take you or call 999.

The NHS also says that if you think you have a dental abscess you should ask for an urgent dentist appointment or call NHS 111, and that you should call 999 or go to A&E if you have trouble breathing, speaking or swallowing, a swollen or painful eye, sudden vision problems or significant swelling in your mouth. Heavy bleeding that will not stop is also a reason for urgent help.

• Swelling of the face, jaw or neck that is getting bigger
• Difficulty breathing, swallowing or speaking
• A high temperature with severe toothache
• Pain that is severe, throbbing and not helped by painkillers
• Trouble opening your mouth

If your dentist is closed, check their answerphone for instructions or call NHS 111 for advice.

If your pain is bearable but has lasted more than a couple of days, book a dental appointment soon. Pain on biting is not something to put up with.

If you would like us to look at it, you can book an appointment at our Maida Vale clinic. We will find out what is causing the pain and explain your options.

Tooth pain when biting FAQs

Why does my tooth only hurt when I bite down?

Pain that appears only under pressure often points to a crack, a filling or crown that sits high, or inflammation around the root. It can also come from decay or gum disease. A dentist can test each tooth and work out which one it is.

Can a cracked tooth heal on its own?

No. A cracked tooth does not repair itself the way a broken bone can, and a crack can spread over time. See a dentist so it can be assessed and protected before it worsens.

Why does my filling hurt when I bite?

A filling can feel sore if it sits slightly high, has cracked or loosened, or if the tooth under it has become irritated or has fresh decay. Do not try to adjust it yourself. A dentist can check the bite and fix the filling if needed.

Can a sinus infection make my teeth hurt when I bite?

It can. The roots of the upper back teeth sit close to the sinuses, and the NHS lists toothache among the symptoms of sinusitis. If your nose is blocked and several upper teeth ache, mention it. A dentist should still check that the tooth itself is healthy.

Is pain when biting a dental emergency?

Not always, but it should be looked at soon. It becomes urgent if you have swelling of the face or neck, a high temperature, trouble breathing or swallowing, or severe pain that painkillers do not ease. In those cases use NHS 111, A&E or 999 as described above.

What can I take for tooth pain when biting?

The NHS suggests over the counter painkillers from a pharmacy, used exactly as the packet says, plus warm salt water rinses and soft food. Ask a pharmacist if you are unsure what is suitable for you. These ease the pain for a time, but they do not treat the cause.

Will pain when biting go away on its own?

It may ease for a while, which can be misleading. The cause is usually still there, and decay, a crack or an infection can get worse without treatment. It is better to book an appointment than to wait.

How much is an emergency dental appointment?

Our fee list shows an emergency appointment at £99, which includes a prescription and periapical X rays. Same day slots are available, and any further treatment is explained and priced before it begins.