A dead tooth usually looks darker than the teeth around it, turning yellow, grey, brown or almost black over weeks or months as the nerve inside breaks down. A dead or dying tooth is a serious problem that won’t heal on its own, but it can often be saved with root canal treatment, especially when it’s caught before infection spreads into the bone.
Dentists call it a non-vital or necrotic tooth. The pulp, which is the living tissue inside with nerves and blood vessels, has died. Sometimes it hurts a lot on the way there. Sometimes it doesn’t hurt at all, and a colour change is the only clue.
Because a dead tooth can look normal on the outside for a while, digital radiography is one of the main ways it’s diagnosed. X-rays can show changes in the bone at the root tip long before you’d notice anything.
After treatment, a darkened front tooth can often be lightened with internal whitening, and some people pair that with professional teeth whitening in Barrie for an even smile. Back teeth usually need a crown to protect them, which is part of crowns and bridges care.
You can read about Ardagh Family Dentistry and the team’s approach before your visit. Here’s what to look for, why teeth die, and what your options are.
What is a dead tooth?
A tooth has three layers: hard enamel on the outside, dentin underneath, and the pulp in the centre. The pulp keeps the tooth alive and sensitive.
When the pulp loses its blood supply or becomes infected and dies, the tooth is considered non-vital, or dead. The tooth structure is still there, held in place by the ligament and bone around the root. But it no longer has living tissue inside, and the dead pulp can become a home for bacteria.
What does a dead tooth look like?
Colour changes
- Slight yellowing in the early stages
- Grey or blue-grey, very common after an injury
- Brown or dark grey as the breakdown products of the pulp stain the dentin
- Pink tint (rare), which can signal internal resorption and needs prompt attention
The colour change happens because blood and tissue inside the tooth break down, and those pigments seep into the tiny tubules of the dentin. It’s similar to a bruise, except it doesn’t fade on its own.
Other signs
- A pimple-like bump on the gum near the root (a fistula or “gum boil”)
- Swelling in the gum or face
- Bad taste or bad smell from one area
- Tenderness when biting or tapping on the tooth
- No reaction to cold, when the teeth beside it do react
Does a dead tooth hurt?
It depends on the stage.
| Stage | What you may feel |
|---|---|
| Inflamed pulp (pulpitis) | Sharp or lingering pain to hot and cold, throbbing, worse at night |
| Pulp dying | Pain may suddenly ease as the nerve stops working |
| Dead pulp, no infection yet | Often no pain; colour change may be the only sign |
| Infection at the root (abscess) | Pain when biting, swelling, gum bump, bad taste |
That “sudden relief” stage fools a lot of people into thinking the problem has gone away. It usually means the nerve has died, and infection can follow.
What causes a tooth to die?
Trauma
A knock from a ball, fall, car accident or bite on something hard can damage the blood vessels entering the root tip. The tooth may look fine at first, then darken weeks, months or even years later. Front teeth are the most common victims.
Deep decay
Untreated cavities let bacteria reach the pulp. The pulp becomes inflamed, then infected, then dies.
Cracks
A crack can let bacteria seep in slowly, killing the pulp over time.
Large or repeated fillings
Each time a tooth is drilled and filled, the pulp is stressed. Teeth with many old fillings are more likely to die eventually.
Grinding
Heavy grinding can bruise the pulp repeatedly and cause cracks.
How dentists confirm a tooth is dead
- History. Any injuries, pain history, past dental work.
- Visual exam. Colour, swelling, gum bumps.
- Cold test. A cold stimulus is placed on the tooth. A healthy tooth responds; a dead one usually doesn’t.
- Electric pulp test. A gentle current checks for nerve response.
- Tap and bite tests. Tenderness can point to inflammation at the root tip.
- Digital X-rays. Show dark areas at the root tip (bone loss from infection), canal changes and cracks.
Can a dead tooth be saved?
Very often, yes. The two main options are root canal treatment or extraction.
Root canal treatment
The dead pulp is removed, the canals are cleaned and disinfected, and they’re sealed to stop bacteria returning. The tooth stays in your mouth, held by healthy ligament and bone.
- Usually 1 to 2 visits under local anaesthetic
- Back teeth usually need a crown afterward to prevent fractures
- Front teeth may only need a filling, plus internal whitening if they’re discoloured
Extraction
If the tooth is badly cracked, has too little structure left, or the root is damaged, removal may be the best option. The gap can be filled with an implant, bridge or partial denture.
Root canal vs extraction for a dead tooth
| Root canal | Extraction | |
|---|---|---|
| Keeps your natural tooth | Yes | No |
| Recovery | Mild soreness for a few days | Socket heals over a few weeks |
| Follow-up treatment | Crown or filling | Implant, bridge or denture to replace it |
| Effect on nearby teeth | None | Teeth can drift if the gap isn’t filled |
| Long-term outlook | Treated teeth often last decades | Depends on replacement chosen |
Can you whiten a dead tooth?
Regular whitening on the outside of the tooth has limited effect, because the stain comes from inside. Internal whitening (sometimes called walking bleach) is done after a root canal:
- The root canal filling is sealed off below the gumline.
- Whitening material is placed inside the tooth and sealed in.
- It’s left for several days, then checked and repeated if needed.
- Once the shade matches, the opening is permanently filled.
If internal whitening doesn’t fully match, a veneer or crown can cover the tooth.
What happens if you leave a dead tooth?
- Infection can spread from the root tip into the jawbone, forming an abscess
- Swelling can spread into the face or neck in rare cases
- Bone around the root can be lost, making future treatment harder
- The tooth becomes brittle and can fracture
- The colour usually gets darker over time
Safety note: Facial swelling, fever, or trouble swallowing or breathing alongside a tooth problem needs urgent medical or dental care the same day. Don’t wait for a regular appointment.
Myths about dead teeth
“If it doesn’t hurt, it’s fine.”
Dead teeth are often painless. Infection can still be quietly damaging the bone.
“A grey tooth after an injury will go back to normal.”
Occasionally a tooth that darkens slightly after a knock recovers. Most teeth that turn and stay grey have a dead or dying pulp and need assessment.
“Root canals are worse than extractions.”
Modern root canals are similar to having a filling for most people. Keeping your natural tooth usually costs less time and treatment in the long run than replacing it.
“A dead tooth will fall out on its own.”
Dead teeth are usually still firmly attached. They don’t fall out unless gum disease or bone loss is also present.
Real patient examples
A 34-year-old took a hockey stick to the mouth in high school. Fifteen years later, his front tooth slowly turned grey. A cold test showed no response, and an X-ray showed a small dark area at the root tip. A root canal and internal whitening brought it close to the colour of his other teeth.
A 47-year-old had a molar with a large old filling. She’d had bad pain two months earlier that suddenly stopped. Then a bump appeared on her gum. The tooth had died and abscessed. Root canal treatment cleared the infection, and a crown protected the tooth.
How to protect your teeth from dying
- Wear a mouthguard for hockey, basketball, martial arts and other contact sports
- Treat cavities early, while they’re small
- Get cracked or broken teeth checked quickly
- Wear a night guard if you grind
- Have a dentist check any tooth that was knocked, even if it looks fine
- Keep regular checkups and X-rays as recommended
Dead tooth care with a dentist in Barrie
Ardagh Family Dentistry is a trusted dentist in Barrie with a fully equipped, wheelchair-accessible facility serving families of all ages. We’re in the Ardagh Bluffs area at Circle K Plaza, 225 Ferndale Dr. S., Unit 7, Barrie, ON L4N 6B9.
We welcome new patients and accept CDCP (Canadian Dental Care Plan) patients. Our services include preventive care, sealants, digital radiography, cleanings, sport guards, extractions, root canals, teeth whitening, dentures, crowns, bridges and night guards. If you’re nervous, we offer dentistry with nitrous oxide (laughing gas) to help you relax.
Call +1 705-315-0219 or email info@ardagh.ca if you’ve noticed a tooth changing colour. We’ll do our best to see you quickly, especially if there’s pain or swelling.
All diagnosis and treatment is provided by dentists registered with the Royal College of Dental Surgeons of Ontario (RCDSO), with careful testing before treatment and follow-up afterward.
Frequently asked questions
How long can a dead tooth stay in your mouth?
A dead tooth can stay in place for months or years, but the risk of infection, abscess and fracture rises over time. Treatment is recommended once it’s diagnosed.
Can a dead tooth come back to life?
No. Once the pulp has died, it can’t recover. In some young patients, a tooth that’s only bruised after an injury may recover if the pulp hasn’t actually died, which is why monitoring matters.
Is a dead tooth an emergency?
Not usually, unless there’s swelling, fever or severe pain. It still needs a dental visit soon to prevent infection.
Why did my tooth turn grey years after an injury?
Damage to the blood supply can slowly kill the pulp over months or years. As the tissue breaks down, pigments stain the tooth from inside.
Do dead teeth need a crown?
Back teeth usually do after a root canal, to prevent cracking. Front teeth often only need a filling, unless they’re heavily damaged.
Conclusion
A dead tooth usually turns darker than its neighbours and may cause pain, swelling or a gum bump, or no symptoms at all.
Root canal treatment can often save it, with a crown or internal whitening to restore strength and colour.
Getting a darkened tooth checked early keeps infection from spreading and protects your options.
