A toothache almost always means something is irritating or damaging the nerve inside or around your tooth. The specific cause ranges from a minor cavity to a serious infection, and the type of pain you’re feeling is a surprisingly reliable clue about what’s going on. About one in six adults report experiencing tooth or molar pain in a given year, so this is one of the most common health complaints people deal with.
What the Type of Pain Tells You
Not all toothaches feel the same, and the character of your pain points toward different problems.
Sharp or stabbing pain usually signals a problem with your enamel or the nerves just beneath it. A cavity that has reached the inner layers of your tooth, a crack or chip that exposes sensitive tissue, or worn enamel that reacts to hot, cold, or sweet foods can all produce this kind of sudden, intense jolt. It often comes and goes rather than staying constant.
Throbbing or pulsing pain typically means infection or significant inflammation. An abscessed tooth, where bacteria have reached the root and caused pus to build up, is the most common culprit. Gum infections can also produce deep, radiating pain that’s hard to pinpoint. This type of pain tends to keep you up at night and may get worse when you lie down, because blood flow to your head increases in that position.
A dull, persistent ache is the trickiest to interpret. It can come from grinding your teeth at night (many people don’t realize they do this), pressure from wisdom teeth that haven’t fully come in, or early-stage decay that hasn’t yet progressed to sharp pain. This kind of ache is easy to ignore, but it rarely resolves on its own.
The Most Common Causes
Tooth decay is by far the leading reason for toothaches. The CDC estimates about one in four adults between ages 20 and 64 have untreated cavities. When a cavity is shallow, you might not feel anything at all. Once it gets deep enough to reach the inner tissue of your tooth, called the pulp, bacteria trigger inflammation known as pulpitis. In its early stage, pulpitis is reversible: your dentist can remove the decay and place a filling, and the tooth recovers. But if the infection advances, the pulp tissue eventually dies and can’t be saved. At that point, a root canal or extraction becomes necessary.
Cracked teeth are another frequent cause, and they’re notoriously hard to diagnose because the crack may be too small to see on an X-ray. The telltale sign is a sharp pain when you bite down that disappears the moment you release. Cracks let bacteria slip inside the tooth, starting the same chain of inflammation and infection that cavities cause.
Gum disease can also produce toothache-like pain, especially when infection settles deep into the pockets around tooth roots. And teeth grinding, which often happens during sleep, wears down enamel and strains the jaw muscles, creating a dull soreness that affects multiple teeth rather than just one.
When It’s Not Actually Your Teeth
Sometimes a toothache isn’t a dental problem at all. Sinus infections are one of the most common mimics. Your largest sinuses sit directly above the roots of your upper back teeth, and in some people the tooth roots actually extend into the sinus cavity. When those sinuses become inflamed, the pressure can feel exactly like a toothache. The giveaway is that the pain affects several upper teeth at once rather than a single tooth, and you’ll likely have congestion or facial pressure along with it.
Jaw joint disorders (TMJ problems) can also radiate pain into your teeth, especially if you clench your jaw during stress. In rare cases, pain in the lower left jaw can be a sign of a heart problem, particularly if it comes with chest tightness, shortness of breath, or sweating. This is uncommon, but worth knowing about.
What Happens at the Dentist
Figuring out the exact source of tooth pain isn’t always straightforward, so your dentist will use a few targeted tests beyond just looking and taking X-rays. Cold testing is the most common: a cold stimulus is applied to different teeth, and your response (how quickly you feel it, how intense it is, and how long the sensation lasts) tells the dentist whether the nerve inside is healthy, inflamed, or dead. A healthy nerve responds briefly and calms down. An inflamed nerve overreacts and lingers. A dead nerve doesn’t respond at all.
Percussion testing involves tapping the edge of each tooth with an instrument. Pain on tapping usually means the infection has spread beyond the tooth into the surrounding bone. Your dentist may also have you bite down on a small object to check for cracks, since fractured teeth produce pain specifically on biting pressure. These tests are quick and help your dentist distinguish between problems that can look very similar on an X-ray.
Managing Pain Before Your Appointment
The American Dental Association’s guidelines for acute dental pain recommend a combination approach for the best relief. Taking 400 mg of ibuprofen together with 500 mg of acetaminophen works better than either one alone. These two medications work through different pathways, so combining them provides stronger pain control without doubling up on the same type of drug. You can also take naproxen sodium (440 mg) with acetaminophen as an alternative combination.
A cold pack or ice wrapped in a washcloth held against the outside of your jaw can help reduce swelling and numb the area temporarily. Flossing gently on both sides of the painful tooth is also worth trying, since a piece of food wedged under the gumline can mimic a toothache surprisingly well. If removing it stops the pain, you may have just solved the problem.
What doesn’t work: placing aspirin directly on the gum tissue. This is an old home remedy that actually burns the soft tissue and makes things worse.
Toothaches in Children
Most toothaches in children are brief and caused by tooth sensitivity rather than serious decay. If the pain goes away within 24 hours, it’s generally not urgent. But if it persists beyond a day, a cavity is the most likely explanation, especially on the surface of one of the back molars. You may be able to spot a yellow-brown defect in the enamel.
A dental abscess in a child looks different than mild decay. The pain is severe, throbbing, and gets worse when you tap on the tooth. If the infection progresses far enough, a small bump or “gum boil” will appear on the gum below the tooth. Children with abscesses need to see a dentist promptly for treatment, just as adults do. In the meantime, children’s ibuprofen or acetaminophen and a cold pack on the jaw can help with pain.
Signs That Need Immediate Attention
Most toothaches can wait a day or two for a dental appointment. Some can’t. An untreated dental abscess can spread to the floor of the mouth and throat, causing a dangerous condition called Ludwig angina that can block the airway. It can also lead to sepsis, a bodywide infection.
Head to an emergency room if you notice any of these alongside your toothache: a fever over 100.4°F, swelling that extends to your eye or down your neck, difficulty swallowing or breathing, or difficulty opening your mouth. Severe pain that comes on rapidly and doesn’t respond to over-the-counter pain relievers is also a reason to seek emergency care rather than waiting for a scheduled dental visit. The ADA recommends calling your dentist if pain doesn’t lessen over time or if you can’t be seen within two to three days.