This article is general information for our patients, not a diagnosis. If something in your mouth hurts, changes, or worries you, have it examined.
The question I get asked most about emergencies is a fair one: can I just go to the hospital for this? The short answer is that a hospital emergency room and a dentist do two different jobs, and knowing which you need saves you a long wait for the wrong help. Below I’ll walk through where each one fits, and — the part that matters most — the handful of signs that mean the hospital comes first.
First, a caveat that frames everything else here. Nothing below is a diagnosis. Pain and swelling tell you how urgent a problem is, not what’s causing it — and the ER-or-dentist call turns on signs someone has to size up in person: whether your airway, swallowing and facial swelling are in play, or whether the trouble stays local to the tooth. Pinning down the actual cause takes the fuller picture built up in the chair — your history, a hands-on exam, how the tooth answers specific tests, and an X-ray. So use this to judge where to go and how fast, not to land on an answer.
Can you go to the hospital for tooth pain in Ontario?
You can, and no one will turn you away. But it helps to know what you’ll get. Ontario hospitals aren’t set up for dental treatment — there’s rarely a dentist on staff in the emergency room, and they don’t do fillings, root canals or routine extractions. What an emergency room is built for is the part of a dental problem that can become a medical one: pain that needs stronger relief, an infection that’s spreading, bleeding that won’t stop, and above all a swelling that threatens your airway.
So for a plain toothache — even a bad one — the ER can usually only take the edge off and tell you to see a dentist. For a spreading infection or a serious facial injury, the hospital may be exactly the right place to be first. The rest of this article is about telling those two situations apart.
When should you go straight to the hospital, or call 911?
A small number of dental problems are time-critical, because an infection from a lower tooth can spread into the spaces of the floor of the mouth and neck and, at its worst, press on the airway. That’s the situation where the tooth is almost beside the point — breathing comes first. Go straight to a hospital emergency room, or call 911, for any of these:
- Swelling under your jaw or in the floor of your mouth on both sides, or a tongue that feels pushed up
- Trouble swallowing your own saliva, drooling, or a muffled or “hot potato” voice
- Any difficulty breathing, or a whistling sound when you breathe in
- Swelling spreading toward your eye and starting to close it, or spreading down your neck
- A high fever with facial swelling, feeling confused or very unwell, or a swelling that’s visibly growing by the hour
You don’t need to check off several of these — one is enough. Swelling that crosses to both sides under the jaw, or that changes your voice or swallowing, is the one I’d never sit on. This is also the situation people mean by a true dental emergency in the life-threatening sense, and it’s rare — but recognising it early is the whole point.
Serious injuries belong at the hospital too. If a blow to the face has knocked teeth loose or out and there’s heavy bleeding, a possible broken jaw, or you were knocked out, the emergency room handles the injury first. For a knocked-out or broken tooth on its own, with no other injury, timing matters and a dentist is often the faster route — there’s first aid for a knocked-out or broken tooth worth knowing before you decide.
When to go to hospital for a tooth infection
This deserves its own answer, because “tooth infection” covers a huge range. Most start as a contained abscess at the root of one tooth — sore, sometimes with a small gum boil, but going nowhere fast. That’s a dentist’s job, and a prompt one. What turns an infection into a hospital problem is spread: the swelling moving out of the gum and into the face and neck, and your body starting to feel the strain of it.
The signs that point toward spread are the ones in the list above — swelling reaching the eye or crossing both sides under the jaw, trouble swallowing or breathing, a changed voice, fever and feeling generally unwell. Those tend to point toward an infection that has moved beyond the tooth, and that’s the moment the hospital’s ability to protect your airway and give antibiotics straight into a vein matters. A hot, spreading facial swelling that’s still building is not something to watch overnight.
Short of those red flags, an infection with a swollen face but stable breathing and swallowing is usually one we handle promptly at the practice, sometimes alongside a call to your pharmacist or doctor. The dividing line isn’t how much it hurts — it’s whether it’s spreading and whether it’s affecting your breathing or swallowing.
Why the hospital can’t fix the tooth itself
Here’s the part that surprises people. Even when the hospital is exactly where you should be, it usually doesn’t end the problem — it buys you safety and time. An emergency team can protect your airway if it’s threatened, drain a large collection of pus if there’s one to reach, give strong pain relief, and start antibiotics. What they generally can’t do is treat the source: the tooth that let the infection in.
That matters because antibiotics don’t cure a dental infection on their own. The centre of an abscess has no blood supply, so a tablet or even a drip can’t fully reach it — the medicine holds the infection back and helps you feel better, but the trapped infection stays until the tooth is dealt with. That’s why an infection treated only with antibiotics so often flares again a week or two later. The lasting fix is removing the source, which means draining the tooth, doing a root canal, or taking it out — how we weigh saving a tooth against removing it is a decision we make once we can see what we’re dealing with. So the usual path is: hospital makes you safe, dentist finishes the job.
When a dentist is the right call, not the ER
For the great majority of tooth pain, a dentist is both the faster and the more useful choice. Call us promptly, rather than heading to the hospital, for things like:
- A severe or constant toothache, or one that keeps you up at night
- A swollen face or gum with no trouble breathing or swallowing
- A gum boil or pimple that keeps coming back
- A broken, cracked or knocked-out tooth with no other injury
- A lost filling or crown, or ongoing bleeding from a socket after an extraction
If you’d like to understand what the pain itself might be pointing to before you call, what your tooth pain might be telling you walks through the common patterns — bearing in mind those are clues, not answers.
How I decide what can wait until morning
When someone phones in pain, the first thing I weigh isn’t how bad it sounds — it’s whether anything suggests the infection is spreading or the airway is involved. If breathing, swallowing and the tongue are all fine and the swelling is stable, we’re almost always talking about when to be seen, not where. If any of the airway signs are in play, that conversation changes in a sentence and the hospital comes first.
That’s genuinely hard to judge from a written list, which is why I’d rather you call and describe it than try to score yourself. A thirty-second description over the phone usually sorts urgent from can-wait quickly, and if it’s the hospital you need, we’ll tell you plainly.
Getting through until you’re seen
While you’re waiting to be seen, pain relief can take the edge off, but it only quiets the symptom — it doesn’t treat the tooth, and needing it around the clock is itself a reason to be seen. A pharmacist can tell you which option is right for you, and that’s worth asking about if you’re on other medicines or living with a health condition. Two things to avoid: don’t hold a painkiller tablet against the gum, which burns the tissue and does nothing for the tooth, and don’t lean on a leftover course of antibiotics — a dead or abscessed tooth won’t clear with tablets alone, and self-dosing can mask a spreading infection that needs proper care. A cold compress on the outside of the cheek and sleeping propped up can make the wait more bearable.
What happens when you come in
The first job is working out what’s going on, and it’s the step that genuinely needs you in front of us rather than on a phone line: we track down which tooth is the source, test which nerves are still alive, gauge how far any swelling has travelled, and take an X-ray — then weigh those findings against each other. Those few minutes usually pinpoint what the symptoms alone couldn’t. Comfort comes first, with local anaesthetic and draining any abscess that’s ready to drain. Only then do we treat the cause — a root canal for a tooth worth keeping, or removing one that’s too far gone. If at any point what we find looks like it’s spreading toward the airway, we arrange hospital care straight away; that judgement is part of the exam, not something we leave to you.
If you have tooth pain, a swelling, or an injury and you’re not sure where to turn, call our family-run team at Prince William Way Dental in Barrie on 705-721-9229 and describe it — we’ll help you decide, and get you seen as soon as we can, including evenings and Saturdays. We offer direct billing and accept the Canadian Dental Care Plan (CDCP). You can also book a visit or call us through our contact page, or read more about our emergency dental care in Barrie.
This guide is part of our Emergency Patient Information library, where you’ll find the rest of our guides on dental emergencies, injuries and pain.
