A nagging toothache is one of the easiest things in the world to put off. I see it constantly in Blackburn — busy working adults across the City of Whitehorse who tell me the tooth has been “a bit sore for weeks,” and they’d meant to get it looked at, but work got in the way and it seemed to settle down, so they left it. By the time they’re sitting in my chair, that quiet ache has often become the kind of pain that keeps them up at night.
The tricky thing about a tooth infection is that what looks fine on the outside can be a real problem on the inside. So it’s worth knowing the signs that the nerve inside a tooth — the pulp — may be infected or dying, because catching it early genuinely changes how straightforward the treatment is. Here’s what to watch for, and what to do about it.
What a “root canal infection” actually is
Inside every tooth is a soft core called the pulp. It holds the tooth’s nerve and blood supply, and it’s what gives your tooth its sensation to hot and cold. That pulp sits in a space called the root canal, which runs down through the centre of the tooth into the bone.
When the pulp is healthy, you don’t notice it — you eat, drink and chew without a thought. But if bacteria reach the pulp, through deep decay, a crack, an old trauma, or a heavily filled tooth, it can become inflamed and eventually start to die. Once that happens, the dead tissue becomes a reservoir for bacteria, and that’s what we mean by a root canal infection. It’s also when the tooth tends to get genuinely painful.
The signs below are the ones I’d want any of my patients to recognise.
1. A persistent, throbbing toothache
The most common one. This can range from a dull, constant ache to a sharp, throbbing pain, and patients very often tell me it’s worse at night or when they lie down to sleep. A tooth that hurts for no obvious reason, or a pain that’s steadily getting stronger rather than easing, is worth having assessed rather than riding out.
2. Pain when you bite or chew
Discomfort when you bite down on a particular tooth can have several causes, but an infection is one of them. The bone around the root can become inflamed, or the pressure of chewing pushes on infected tissue inside the tooth. If one specific tooth protests every time you eat on that side, take note of which one.
3. Sensitivity to hot or cold that lingers
A quick twinge from a cold drink that vanishes straight away is usually nothing to worry about. What’s different with an infected pulp is that the reaction is stronger and lasts — a sharp, shooting sensitivity that hangs around for many seconds or longer after the hot or cold has gone. Sensitivity that lingers like that is the kind I’d want to check.
4. Swelling of the gum or face — or a gum pimple
Infection that spreads beyond the root can show up as swelling. That might be:
- A small pimple or bump on the gum near the tooth
- Red, tender or puffy gum tissue
- Swelling in the cheek or under the eye
That little gum pimple in particular is easy to dismiss, especially if it comes and goes, but it’s often the tooth trying to drain an infection.
5. The tooth darkening or changing colour
As the pulp dies, a tooth can gradually go grey, brown or simply darker than its neighbours. Discolouration isn’t always infection — there are other causes — but a single tooth that’s changed colour is worth getting looked at, especially if it comes alongside any pain or swelling.
6. A bad taste or persistent bad smell
An infected tooth can leak fluid or pus into the mouth through the gum. You might notice an ongoing unpleasant taste or a smell that doesn’t shift no matter how well you brush. That’s a sign bacteria are active, and it shouldn’t be ignored.
7. Pain bad enough to disturb your sleep
If a toothache is keeping you awake, or noticeably worsens when you lie down, that often points to more advanced inflammation or infection. This kind of pain tends not to settle on its own, and over-the-counter painkillers usually only take the edge off. The longer it’s left, the more involved things tend to get.
What to do if this sounds familiar
The honest message here isn’t to panic — it’s to act promptly rather than hope it passes. Not every ache is an infected nerve; plenty turn out to be a smaller problem caught in good time. But the only way to know is a proper assessment, which usually means a look at the tooth and an X-ray, because a lot of what’s happening lives below the gum line where the eye can’t see it.
If you’ve had that grumbling tooth for a while but you’re not in acute pain, the sensible step is simply to get it checked — often at a routine check-up and clean, where we can catch these things before they escalate. If you’re in real pain, have facial swelling, or a tooth has flared up suddenly, that’s exactly what emergency dental care is for, and I’d rather see you the same day than have you wait it out over a weekend.
Whether across in Box Hill or Nunawading, out towards Forest Hill, Mitcham or Vermont, or right here in Blackburn and Blackburn North, the practical thing to know is that these symptoms don’t tend to improve by being ignored — but they respond well when they’re dealt with early.
The reassuring part
Here’s what I always want patients to hear: a tooth infection is one of the more treatable problems we deal with. When the pulp is infected, root canal treatment removes the infected tissue, cleans and seals the inside of the tooth, and — crucially — lets us keep your natural tooth in place rather than losing it. Modern techniques and anaesthetic mean the treatment itself is far more comfortable than its old reputation suggests, and for most people the relief afterwards is significant.
The one thing that genuinely makes a difference is timing. A tooth caught early, before an infection has spread through the bone, is almost always simpler to treat than one that’s been soldiered through for months. So if any of these seven signs rings a bell, don’t file it under “I’ll get to it” — a short appointment now is far easier than what comes later.
If you’ve noticed a persistent ache, lingering sensitivity, swelling or a tooth that’s changed colour, please get it checked — you’re welcome to book online or call us on (03) 8838 8820. We’re at 129A Canterbury Road, Blackburn — a short walk from Blackburn Station and easy to reach from across the Whitehorse area.