Why Does My Tooth Hurt When I Bite Down?
Pain when you bite usually means something is moving or inflamed that should not be: a crack in the tooth, a filling or crown sitting a little high, decay that has reached the nerve, or infection at the root tip. The pattern of the pain tells us a lot, which is why we check before we treat.
What usually causes pain when biting down?
A short list of the usual suspects, and then we will sort them out.
A cracked tooth, which flexes under load and pinches the nerve. A filling or crown that sits a hair too tall, so that tooth takes the hit before any of its neighbors. Decay that has worked its way down to the nerve. An abscess at the tip of the root, which makes the tooth feel like it is sitting in a bruise. A sore ligament around the root from clenching at night or biting down on something unexpectedly hard, which is the dental equivalent of a sprained ankle. A gum infection in the pocket next to the tooth. And on the upper back teeth, sinus pressure, because the roots of those molars sit right under the sinus floor and a head cold can make three teeth ache at once.
Several of these feel almost identical from the inside. That is why I do not guess from a description over the phone.
Why does a cracked tooth hurt when you let go, not when you press?
This one has a signature, and once you know it you will recognize it. You bite down and it is fine, or close to fine. Then you release, and there is a sharp zing that is gone a second later.
Under pressure, the crack flexes open a tiny amount. When you let go, it snaps shut. That movement pushes fluid inside the tooth against the nerve, and the nerve registers it as a quick stab. It tends to be one spot on one tooth, and it often shows up with one kind of food: nuts, seeds, popcorn, crusty bread, anything that loads a single cusp.
Cracks rarely show on an x-ray, because the crack runs in the same direction the x-ray beam travels. So we hunt for them a different way. A bite test on each cusp one at a time, a cold test to see how the nerve responds, a bright light shined through the tooth, which lights up a crack like a line in glass, and a CBCT scan when I am worried the crack has reached the root. Caught early, a cracked tooth usually keeps its nerve and gets covered before the crack spreads. Caught late, the crack can run down into the root, and at that point the options narrow.
Could it be my new filling or crown?
Possibly, and this is the easiest one to fix. When a restoration sits even slightly high, that tooth meets its opposite first every time you close, hundreds of times a day. The ligament around the root gets bruised, and the tooth starts to feel sore and a little loose.
The fix is a bite adjustment. We mark the bite with colored paper, polish the high spot for a minute or two, and the tooth usually settles within a few days. No numbing, no new filling.
Some sensitivity after a composite filling is normal and fades over a few weeks. Steady pain on biting, or pain that is getting worse instead of better, is different. That is a reason to come back in, not something to wait out. The same goes for a same-day crown. We check the bite carefully before you leave, but your jaw knows things in the first week that I cannot fully see in the chair.
When does bite pain mean the nerve or an infection is involved?
When decay reaches the nerve, or an abscess forms at the root tip, the tooth feels tall. It is tender when I tap it, sore to chew on, and the pain is more of a dull, constant ache than a quick zing.
Other signs point the same direction: pain that lingers after hot or cold instead of fading in a few seconds, pain that wakes you up at night, swelling in the gum or cheek, a small pimple on the gum near the tooth, or a bad taste that keeps coming back.
That cluster is root canal territory. I wrote about how I decide whether a tooth truly needs one, and the short version is that the sooner an infected nerve is treated, the simpler the treatment is and the better the tooth holds up afterward.
How do we figure out which one it is?
The exam is a series of small tests, each one ruling things in or out.
I tap each tooth in the area, because an abscessed tooth reacts and a cracked tooth usually does not. You bite on a small stick cusp by cusp, which finds a crack. A cold test tells me whether the nerve is healthy, inflamed, or gone. Marking paper shows me exactly where your teeth meet and whether one spot is taking too much load. Digital x-rays show decay, bone loss, and infection at the root tip. And when something still does not add up, a CBCT scan gives me a three-dimensional look at the root and the bone around it.
The point of all that is to diagnose first. Sometimes the answer is a two-minute bite adjustment and a recheck in two weeks. I would much rather do that and see you settle down than start a procedure on a tooth that only needed a polish.
What does conservative treatment look like?
The fix matches the cause, and nothing more.
A high bite gets adjusted. A cracked tooth gets covered, usually with a bonded onlay or a conservative crown, which holds the tooth together so the crack cannot spread. This is the one situation where a crown is the conservative choice, because the alternative is watching the crack travel. If you have been told you need a crown and the reason was not clear, I wrote about how to think through a second opinion.
A nerve problem gets a root canal, not an extraction. The tooth stays, and I do those here in our Bellevue office.
A clencher or grinder gets a night guard, because a sore ligament will keep coming back until the load comes off. For heavy clenchers with tired jaw muscles, Xeomin for the jaw muscles is an option we can talk through.
Extraction and an implant are the result of when a crack has run down the root and the tooth cannot be saved. That is the whole reason early intervention matters.
What should I do until my appointment?
Chew on the other side. Skip the hard and sticky foods for now. An over-the-counter pain reliever as directed on the label is fine. And stop testing the tooth. Biting down to see if it still hurts is a natural reflex, but every test flexes the crack or bruises the ligament a little more.
Call sooner than your scheduled visit if swelling shows up, if the pain starts to linger after hot or cold, or if it begins waking you up. Those are the signs that the nerve is getting involved, and I wrote a separate post on what to do in a dental emergency if things change quickly.
Bite Pain FAQ
Will the pain go away on its own?
A bruised ligament from biting something hard can settle in a week or two if you rest the tooth. A crack, deep decay, or an infection does not heal on its own, and the pain usually fades and returns rather than disappearing. If it has been more than a couple of weeks, or it is getting worse, it needs a look.
Can a cracked tooth be saved?
Usually, yes, if it is caught before the crack reaches the root. An onlay or crown holds the tooth together, and the nerve often stays healthy. Once a crack runs down the root, the tooth typically cannot be saved, which is why we take early bite pain seriously.
Why does it only hurt with certain foods?
Foods like nuts, seeds, and crusty bread load one cusp at a time, which flexes a crack or presses on a high spot. Soft foods spread the pressure across the whole tooth. Pain that shows up only with specific foods is a strong clue pointing toward a crack or a bite issue.
Can a sinus infection make my teeth hurt when I bite?
Yes. The roots of the upper back teeth sit just under the sinus floor, so sinus pressure can make several teeth ache at once, especially when you bend over. If the pain is in one tooth only, or comes with a zing on release, it is more likely the tooth itself. An exam sorts it out quickly.
Should I wait until my next cleaning?
If the pain is new and mild, a few days of resting the tooth is reasonable. Beyond that, do not wait. A small crack found this month is an onlay. The same crack found at a cleaning six months from now can be a root canal or a lost tooth.
If a tooth hurts when you bite, call or text 425.643.5778 or request an appointment. Finding the cause early is usually the difference between a small fix and a big one.
Reviewed by Dr. Victor Bauer, DDS. Last updated October 2026.
Dr. Victor Bauer, DDS is a general dentist and the owner of Family Dental Care of Bellevue, located in the Factoria neighborhood of Bellevue, WA. He provides comprehensive family care including dental implants, Invisalign, and same-day CEREC crowns. Questions about your smile? Call 425.643.5778 or request an appointment.
