Jaw Pain From a Tooth: What Causes It and What to Do

How a Tooth Sends Pain Into Your Jaw

Your teeth and your jaw share the same nerve. The large nerve that carries feeling from your face, the trigeminal nerve, branches out to the teeth, the gums, the jawbone, and the skin over it. That means your brain is not always good at pinpointing exactly where a signal is coming from. A problem in a lower molar can read as a deep ache along the jaw. A problem in an upper tooth can read as pain in the cheek and upper jaw, sometimes up toward the ear.

This is called referred pain, and it is why people are often sure the pain is in their jaw or ear when the source is a tooth two centimetres away. The tooth may not even be the part that hurts most. So a jaw that aches on one side, especially alongside a tooth that is sensitive, tender to bite on, or recently troublesome, is worth treating as a tooth problem until a dentist rules it out.

The Tooth Problems That Cause Jaw Pain

A handful of tooth problems account for most jaw pain that starts in the mouth:

• An infected or dying nerve. When the nerve inside a tooth dies and the infection collects at the root, it can build into an abscess in the jawbone, and that pressure aches deep in the jaw. Our guide to what a tooth abscess is explains how it forms, and what causes a tooth infection covers how it is treated.
• A cracked tooth. A crack running into the tooth can send a sharp jolt into the jaw when you bite or let go, and a deeper crack aches between bites too. If your jaw pain spikes on chewing one spot, read a cracked tooth and why a tooth hurts when you bite down.
• A wisdom tooth. A wisdom tooth stuck against its neighbour or half-buried under the gum pushes on and inflames the back of the jaw, which is one of the most common reasons a young adult's jaw aches on one side. When a wisdom tooth needs taking out walks through it.
• Deep decay reaching the nerve. A large cavity that has reached the nerve inflames it, and that inflammation refers pain outward into the jaw well before there is any swelling to see.
• Grinding or clenching. This one is usually the jaw muscle rather than a single tooth, but heavy night-time grinding can leave teeth sore and the jaw aching each morning, and over time it can crack a tooth. It often points back to a tooth in the end.

Is It the Tooth or the Jaw Joint?

Not all jaw pain comes from a tooth. The jaw joint itself, the hinge just in front of your ear (the TMJ), can ache from grinding, clenching, stress, or overuse, and that is a different problem with a different fix. A few things help tell them apart, though only an exam settles it:

• Points to a tooth: one tooth is sensitive to hot, cold, or biting; the ache is worse lying down at night; there is a bad taste, a gum pimple, or swelling near a tooth; tapping one tooth reproduces the pain.
• Points to the joint: the pain sits right at the hinge in front of the ear; the jaw clicks, catches, or is stiff to open wide; both sides ache; it is worse after a long chew or a stressful week, not tied to any one tooth.

The two also overlap. A grinding habit can inflame the joint and crack a tooth at the same time. If you cannot tell, treat it as a tooth first, because a dental infection has a clock on it and a joint strain usually does not.

What You Can Do Before You're Seen

None of this fixes the cause, but it can take the edge off while you arrange to be seen:

• Over-the-counter painkillers. An anti-inflammatory like ibuprofen, if it is safe for you, works well on the throb from an inflamed nerve or an angry joint. Our guide to painkillers for a toothache covers what actually helps.
• A cold compress on the outside of the jaw eases swelling and a sore joint. For muscle ache from clenching, gentle warmth can help instead.
• Rest the jaw. Soft food, smaller bites, and skipping gum give an overworked joint or a cracked tooth a break.
• Sleep propped up. Lying flat raises the pressure in an infected tooth, which is why jaw and tooth pain so often peak at night. Our guide on how to sleep with a toothache goes further.

What will not fix it is waiting. If a tooth is behind the pain, the ache easing off for a day is the infection or inflammation resting, not resolving, and waiting to see whether it clears is usually the more expensive choice. A tooth that needs a straightforward root canal now is a harder job once an abscess has had a few weeks to spread in the jaw.

When Jaw Pain Is an Emergency

Most jaw pain from a tooth can wait for a same-day or next-day appointment. Some of it cannot, and a couple of things are not a dental appointment at all.

Go straight to a hospital emergency room, not the dentist, if you have swelling under the jaw or in the floor of the mouth that is spreading, swelling pushing up under the tongue, a fever with a swollen face, or any trouble breathing, swallowing, or opening your mouth. A dental infection that reaches the spaces under the jaw can threaten the airway, and that moves faster than any appointment. Our guide to facial swelling from a tooth infection covers the warning signs.

There is one more that has nothing to do with your teeth. Jaw pain, especially on the lower left, that comes on with chest pressure or tightness, breathlessness, a cold sweat, or nausea can be a sign of a heart attack, not a tooth. Call emergency services. It is rare, but it is the reason no honest dentist tells you to sit tight with new jaw pain and heavy chest symptoms.

For anything short of those, jaw pain tied to a tooth still wants seeing promptly. If you are not sure how urgent yours is, when a toothache is a real emergency helps you judge it.

If your jaw is aching and you think a tooth is behind it, call or WhatsApp 055-985-8845 and we will find which tooth it is and treat it. We are in Ramat Beit Shemesh, open Sunday to Thursday 8:00 AM to 8:00 PM and Friday 8:00 AM to 2:00 PM, with after-hours emergency treatment outside those hours. Describe the pain or send a photo of the tooth or gum if it is easier. Our dental infection treatment and emergency dentist pages explain how we track the pain to its source and clear it.

For guidance from sources with nothing to sell, the ADA's MouthHealthy explains what a dental abscess is and why it needs treating and how an impacted wisdom tooth causes jaw pain, and the American Association of Endodontists covers how a root canal clears an infected tooth.