It flares up, you take something, it settles, and for a week you forget about it. Then it’s back, usually at night. A toothache that comes and goes is easy to live with for a while, and that’s exactly what makes it worth understanding.
Key points
- Pain that comes and goes still has a cause, and the pattern says a lot about what it is.
- Cold that lingers, and pain that starts on its own or wakes you at night, usually means the nerve inside the tooth is in trouble.
- A tooth that stops hurting hasn’t always gotten better. Sometimes the nerve has died.
- Orajel is fine to get through a night. It numbs the gum, not the inside of the tooth, which is why it often stops working.
- Swelling that spreads toward your eye or neck, trouble swallowing, or a fever with swelling means a hospital, tonight.
What the pattern usually means
We can’t tell you what’s wrong from a description, but the way a tooth hurts narrows it down a lot. Here’s how we think about it.
| If it hurts like this | It often points to |
|---|---|
| A quick zing with cold that’s gone in a second or two | Sensitive root surface or an irritated tooth. Annoying, usually not urgent, still worth mentioning. Sensitive at the gum line? |
| Cold that keeps aching for thirty seconds or more after it’s gone | A nerve that’s inflamed beyond recovery. This is the most useful symptom you can tell us about. |
| Something cold makes it feel better, not worse | Usually an infection in the tooth. It needs to be evaluated. |
| Pain that starts on its own, or wakes you up at night | Usually the nerve. Pain with no trigger is a different category from pain when you bite. |
| Sharp pain on one spot when you bite, or when you let go | Often a crack, but also a filling that sits high, a shifted bite or an infected tooth. Why does my tooth hurt when I bite? |
| Several upper back teeth ache at once, often during a cold or sinus trouble | Sometimes your sinuses, since those roots sit right under them. |
| Teeth that feel sore or bruised when you wake up | Often clenching or grinding at night. Why is my jaw always tight? |
| A small bump on the gum that comes and goes, sometimes with a bad taste | A drain for an infection at the root. It isn’t a maybe. |
One more thing makes this tricky: upper and lower teeth on the same side share nerve pathways, so people often point at the wrong tooth, or even the wrong jaw. That’s why we test the teeth instead of going by where it seems to hurt.
Why it hurts more at night
Night pain is one of the signals we take most seriously, whatever the reason it shows up then. A tooth that hurts while you’re lying still, with nothing cold or sweet anywhere near it, is usually telling you the problem is inside the tooth, not on it. If a tooth is waking you up, call in the morning instead of waiting for the next flare.
Why it stops, and why that isn’t good news
The quiet stretch is the part that fools people. A tooth that hurt badly for a week and then went quiet hasn’t always gotten better. Often the nerve has finished dying. The pressure that caused the pain is gone because the tissue producing it is gone, and the infection can move out of the root tip into the bone with no warning attached.
The American Association of Endodontists uses exactly that story as a teaching case: a lower molar that was sensitive to cold and sweets for a few months, then quieted down. The nerve had died, and the tooth needed a root canal. Some teeth die with even less warning. In one study of 2,202 upper front teeth treated with root canals, about 40% of the teeth whose nerve had died had no history of pain that came on by itself or lingered.
American Association of Endodontists. Endodontic Diagnosis. Endodontics: Colleagues for Excellence, Fall 2013. Michaelson PL, Holland GR. Is pulpitis painful? Int Endod J. 2002;35:829-32. PubMed
This is why we’d rather see you during the bad week than three months later. Relief isn’t the same as resolution, and the quiet period is when a tooth that could have been saved often becomes an extraction.
Why the Orajel stopped working
A numbing gel like Orajel is fine to get through a night. That’s what it’s for. But it numbs the surface of the gum, and a toothache that comes and goes usually starts inside the tooth, where the gel can’t reach. Read the label and you’ll see it says so: it’s for minor irritation or injury of the mouth and gums, and not for more than 7 days unless a dentist or doctor says otherwise.
So when the gel stops helping, it isn’t that you need a stronger one. The tooth has moved past what any gel can do. And if you find yourself using it on the same tooth week after week, that tooth needs to be looked at.
Orajel 4X Medicated Toothache & Gum Gel, Drug Facts label, DailyMed (National Library of Medicine). The label also says to stop and get medical help right away for pale, gray or blue skin, headache, a racing heart or shortness of breath, signs of a rare but serious reaction to benzocaine.
What helps until you’re seen
- Ibuprofen, if it’s safe for you to take. An anti-inflammatory usually helps dental pain more than acetaminophen (Tylenol).
- Don’t hold an aspirin against your gum. It burns the tissue and does nothing for the tooth.
- A numbing gel for the night, not for weeks.
- Chew on the other side, and skip very cold or very hot drinks on that side if they set it off.
Call us in the morning if
- the tooth wakes you up at night, or starts hurting on its own
- cold keeps aching long after it’s gone
- it hurts on one spot when you bite or let go
- there’s a bump on the gum, or a bad taste that comes and goes
- you’ve been using Orajel or painkillers on the same tooth for more than a few days
- it hurt for a while and then suddenly stopped
Go to a hospital emergency room tonight, not a dentist, if the toothache comes with swelling spreading toward your eye or down into your neck, trouble swallowing or breathing, a change in your voice, a fever along with facial swelling, or you can’t open your mouth normally. An infection that starts at a tooth can spread into the neck. It’s rare, but it’s a real emergency. More on dental emergencies →
How we work out which tooth, and why
We test the nerve rather than guessing from the story. Cold on the suspect tooth and on its neighbors, tapping to check the ligament around the root, and digital X-rays to look for the dark area at the root tip that shows up when infection has reached the bone. When a case needs more, a 3D CBCT scan shows what a standard X-ray can’t.
Comparing against the neighboring teeth is the part that matters. A tooth that responds differently from the ones on either side is telling you something. One that responds the same as its neighbors probably isn’t the culprit, however much it seems to hurt.
If it turns out to be the nerve, a root canal is usually what lets you keep the tooth. We diagnose it here and refer the treatment to an endodontist who does them every day, then take care of the crown afterward. Signs you may need a root canal and root canal or pull it? go further.
If you’re in pain on a day we’re open, call 702-734-0776. You don’t need to be a patient already to be seen for pain. Calling early in the day helps more than anything. Hours and what to do after hours.
General education, and not a substitute for an exam.