That “just a toothache” feeling can turn into a full-blown dental emergency fast. The trick is knowing when it’s urgent (go now), when it’s time-sensitive (book ASAP), and when it can wait a little without putting your health at risk.
A root canal (also called root canal treatment or endodontic therapy) is used to save a tooth when the soft tissue inside it (the pulp) becomes inflamed or infected—often from deep decay, cracks, or previous dental work.
First: When it’s urgent (don’t wait)
If you have any of the following, treat it as urgent—contact an emergency dentist right away, and go to the ER if you can’t reach a dentist:
- Facial swelling + fever
- Swelling that affects your ability to breathe or swallow
- Rapidly spreading swelling (jaw/neck/face)
- Feeling very unwell (fever, chills, weakness) with dental pain
- Severe pain with a visible “pimple/boil” on the gum or draining pus (can signal an abscess)
These signs can indicate a spreading infection. Mayo Clinic specifically notes that facial swelling with fever and especially trouble breathing or swallowing are reasons to seek emergency care.
The decision guide: should you book today, this week, or monitor?
Think of root canal symptoms in three urgency levels:
1) Book TODAY / within 24–48 hours (high likelihood of pulp infection)
You don’t need to be in “10/10 pain” to need help. Book quickly if you have:
- Severe pain when chewing or biting
- Lingering sensitivity to hot/cold (doesn’t fade quickly)
- Throbbing pain that wakes you up or comes in waves
- A gum “pimple” (fistula) near one tooth, with or without a bad taste
- Swelling or tenderness in the gum near a specific tooth
- A cracked or chipped tooth with new sensitivity/pain
These are classic warning signs used by endodontists to flag possible pulp damage or infection.
2) Book THIS WEEK (could be progressing)
Book soon (and don’t ignore it) if you notice:
- Intermittent pain that keeps returning to the same tooth
- Sensitivity that’s getting worse over days
- A tooth that feels “different” when you bite, even if it’s mild
- A tooth that looks darker/grey after trauma
A darkening tooth after injury can be a sign the nerve is compromised, even if pain is minimal.
3) Monitor briefly (but don’t self-diagnose)
Some symptoms can mimic “root canal pain” but may come from other issues (like gum irritation, sinus pressure, or bite problems). Consider monitoring briefly if:
- Sensitivity is mild and improving day-by-day
- Discomfort happens only with very cold foods and fades quickly
- Pain is generalized (not clearly one tooth)
- You recently had a filling and the bite feels “high” (can cause chewing pain)
Even then, if symptoms last or escalate, it’s safer to book an exam—because infections don’t reliably “cool off” on their own.
Symptoms checklist: do you recognize these root canal red flags?
Use this as a quick self-check. If you tick two or more, it’s usually worth booking an assessment soon.
Pain & sensitivity
- ☐ Pain when biting/chewing
- ☐ Lingering hot/cold sensitivity
- ☐ Spontaneous throbbing pain (no trigger)
- ☐ Night pain or pain that wakes you up
Visible / local changes
- ☐ Swollen/tender gum near one tooth
- ☐ Gum “pimple” or bump that comes and goes
- ☐ Bad taste or odor from one spot
- ☐ Tooth looks darker/grey
History
- ☐ Deep cavity or large old filling on that tooth
- ☐ Cracked/chipped tooth or past trauma
(These are consistent with guidance commonly published for patients by endodontic associations and dental organizations.)
Why root canals become necessary
A root canal is typically needed when bacteria reach the pulp—often through deep decay, cracks, or leaky/failed fillings.
Once the pulp is infected, it usually needs to be removed to stop the infection and save the tooth.
A common end-stage issue is an abscessed tooth (a pocket of infection).
Dental and medical references describe abscesses as infections that can worsen and spread without treatment—one reason dentists take swelling seriously.
“But the pain stopped”—does that mean it can wait?
Not always. Sometimes pain reduces because pressure changes or the nerve becomes less responsive. That doesn’t guarantee the infection is gone.
If you had strong symptoms and then sudden relief—especially with a history of swelling, a gum pimple, or a heavily restored tooth—book an exam.
What your dentist in Toronto will do to confirm (and rule out look-alikes)
A proper diagnosis usually includes:
- Questions about your symptoms (what triggers pain, how long it lingers)
- Clinical tests (cold test, percussion/tapping, bite test)
- Dental X-rays to look for decay, deep fillings, infection signs, or bone changes
Public health guidance describes this kind of exam-and-imaging approach for diagnosing an abscessed tooth and related infection.
When it can wait (a little) — common situations that mimic root canal pain
Some issues feel dramatic but are not necessarily “root canal emergencies”:
- High bite after a new filling or crown → pain on chewing only
- Reversible pulp irritation (early decay or sensitivity) → quick, fading sensitivity
- Gum inflammation from trapped food → localized tenderness that improves with cleaning
- Sinus pressure → upper tooth ache across multiple teeth
Still, if you’re unsure, it’s better to book—especially if symptoms persist beyond a few days or worsen.
What a root canal actually does (simple explanation)
Root canal treatment removes inflamed/infected pulp tissue, cleans and disinfects the inside of the tooth, then seals it to prevent reinfection—so you can keep your natural tooth instead of extracting it.
In many cases, the tooth is then protected with a crown, especially if it’s a back tooth or has a large filling history.
Root Canal Cost in Toronto (Ballpark Pricing)
In Toronto, the cost of a root canal usually depends on which tooth needs treatment (front tooth vs premolar vs molar), how many canals the tooth has, and whether the case is straightforward or more complex (calcified canals, difficult access, or retreatment).
Using the Ontario Dental Association (ODA) Suggested Fee Guide as a benchmark, root canal therapy fees for permanent teeth (procedure only, excluding the final filling/crown and typically excluding the pre-op exam/diagnostic tests) range from about $612 for a one-canal tooth up to about $1,205 for four or more canals in the ODA guide.
Real-world Toronto estimates published by dental clinics commonly align with (or extend beyond) that range depending on complexity: for example, molar root canals are often quoted around $800–$1,200, while complex molars may be $1,000–$1,800+.
Also remember: many teeth—especially molars—often need a crown after a root canal, which is an additional fee and can significantly change the total treatment cost.
What to do right now (a practical next-step plan)
If you have urgent signs
- Seek same-day care.
- If you have fever + facial swelling and can’t reach a dentist, or you have trouble breathing/swallowing, go to the ER.
If you have time-sensitive symptoms
- Book an appointment within 24–48 hours.
- Avoid chewing on that side.
- Use dentist-approved pain relief as appropriate for you (follow label directions; ask a pharmacist/doctor if you have medical conditions).
If symptoms are mild and improving
- Keep monitoring for 24–72 hours.
- If symptoms linger, return, or intensify—book.
Bottom line
If you remember one thing, make it this: pain plus swelling, fever, or a gum pimple is not a “wait and see” situation. Root canal problems are often manageable when treated early, and the goal is almost always the same—stop infection, relieve pain, and save the tooth.