Quick answer
A dead tooth nerve (necrotic pulp) occurs when the living tissue inside a tooth dies due to decay, trauma, or infection. Unlike a healthy tooth, a tooth with a dead nerve often stops hurting as the nerve tissue is destroyed. This does not mean the problem has resolved. Without treatment, a necrotic tooth can become a source of ongoing infection, bone loss, and spreading dental disease. Treatment is usually root canal therapy or extraction.
One of the most confusing things about a dying tooth is that the pain often disappears. It’s easy to think you’re in the clear. In reality, the tooth has just gone quiet, and the nerve is not able to talk to your brain anymore.
What is a dead nerve in a tooth?
Inside every tooth is a soft tissue called the pulp. It’s home to the blood vessels and nerve fibres that keep your tooth alive and feeling things. The pulp runs from the top of the tooth all the way down through the roots into the bone underneath.
When the pulp dies, usually because of an untreated cavity, a hard knock to the tooth, or a crack, the nerves inside also stop working. Dentists call this a non-vital tooth. It’s still sitting there in your mouth, but the living part inside has died.
The death is not always sudden. The pulp tends to fade out in stages: first, it gets inflamed, then partly dies off, then dies completely. Each stage feels a little different, which is why the symptoms can be so confusing.
Signs your tooth nerve may be dead or dying
Symptoms vary depending on the stage of pulp death and whether infection is present at the root tip. Here is what to watch for:
Early signs — pulp is dying but not yet fully dead
- Sudden tooth sensitivity, especially to hot food or drinks, where the pain hangs around for several seconds after you’ve finished
- Aching or throbbing for no obvious reason, often worse at night when you lie down
- Pain when biting or chewing
- A dull, lingering toothache that doesn’t seem to be triggered by anything specific
Later signs — nerve is fully or mostly dead
- Pain stops entirely — the tooth goes quiet. This is often mistaken for recovery.
- Tooth discolouration — the tooth may darken to grey, brown, or yellow as the dead tissue inside breaks down and stains the surrounding dentine
- A small pimple or bump on the gum near the tooth (called a dental abscess or sinus tract) — this is pus draining from the root tip infection
- Bad taste or bad breath that persists despite brushing — caused by bacterial breakdown of the pulp tissue
- Swelling in the gum or jaw around the affected tooth
| Important: A tooth with a dead nerve can still flare up and become very painful.Even after the nerve dies, bacteria keep multiplying inside the tooth. Eventually, they spread out through the tip of the root and into the bone around it, forming what’s called an abscess. This can suddenly trigger severe pain and swelling, even though the tooth seemed to have “settled down” weeks or months earlier. |
Dead nerve tooth symptoms comparison at a glance
| Symptom | Dying nerve (pulpitis) | Dead nerve (necrosis) | Live healthy tooth |
|---|---|---|---|
| Response to cold | Prolonged pain/sensitivity | Little or none | Brief, normal sensitivity |
| Response to heat | Significant pain | Little or none | Brief, normal sensitivity |
| Spontaneous pain | Yes — often throbbing | Absent or mild | No |
| Tooth colour | Normal | Darkened (grey/brown) | Normal |
| Gum appearance | Normal | May show abscess/sinus tract | Normal |
| Bite sensitivity | Possible | Possible (if abscess) | No |
What does a dead nerve in a tooth look like?
You usually can’t see the dead nerve itself because it’s tucked away inside the tooth. What you can see is the effect it has on the outside.
The most common sign is a colour change. A dead tooth tends to darken over weeks or months because the blood vessels inside have ruptured, and the breakdown products seep into the tooth, staining it from the inside out.
If one tooth looks noticeably grey or brown compared to its neighbours, and it is not because of coffee, red wine, or smoking, that’s a clue worth investigating.
On a dental X-ray, your dentist might also spot a darker shadow near the tip of the root. That shadow is a sign the infection has spread into the bone around the tooth.
Can a dead tooth cause pain?
Yes, and in two different ways.
The first is during the dying process itself. An inflamed pulp is one of the most painful things in dentistry. The pulp lives in a tight, sealed space inside the tooth, and as it swells, the pressure has nowhere to go.
The second comes later. Once the nerve has died, an abscess can form at the tip of the root. That can flare up into sudden, severe pain, often weeks or months after you would assumed the issue was over.
Does a dead tooth always need treatment?
Yes. A dead tooth left alone slowly turns into a long-term source of bacterial infection. Possible consequences include:
- Gradual bone loss around the root
- The infection spreading to nearby teeth
- A dental abscess forming, which, in severe cases, can spread to the jaw or neck
- The tooth eventually falling out as the supporting bone breaks down
The earlier it’s caught, the more likely the tooth can be saved with a root canal. The longer it’s left, the more often extraction becomes the only option.
Can a dead tooth nerve heal on its own?
Unfortunately, no. Unlike skin or bone, dental pulp cannot regenerate once it’s died. Your body has no way to clean out a dead tooth nerve on its own. Instead, the empty space becomes a comfortable home for bacteria.
There is one exception. If the pulp is only mildly inflamed, it can sometimes settle down once the cause is fixed. For example, by placing a filling over an exposed area. But once the pulp is properly inflamed or has died, it needs treatment.
What treatment is used for a dead tooth?
Root canal therapy (preferred when the tooth can be saved)
Root canal therapy involves cleaning out the dead or dying tissue from inside the tooth, disinfecting the space, and sealing it up with a special filling material. The tooth is then protected with a crown or filling so it can keep doing its job.
A root canal-treated tooth can last many years, often a lifetime, with proper care. The procedure is done under local anaesthetic, and most patients are surprised at how comfortable it is. It usually feels no different to having a filling placed.
Tooth extraction
If the tooth structure is too compromised to restore, through extensive decay, fracture, or bone loss, extraction may be recommended. This is followed by a discussion of replacement options. This can be through a dental implant, a bridge, or a denture, depending on the tooth’s position and the patient’s overall dental health.
How long can you leave a dead tooth untreated?
There’s no safe waiting period. Even if a dead tooth does not hurt right now, the bacteria inside keep building up. Most dentists will encourage you to act within weeks and not months because the longer the treatment is delayed, the more likely the infection is to spread into the bone or affect nearby teeth.
Frequently asked questions
Can a dead tooth fix itself?
No. Once pulp necrosis has occurred, the tooth cannot recover its vitality. The tissue inside is dead and will not regenerate. Treatment to remove the dead tissue (root canal) or extract the tooth is necessary.
Is a dead tooth always painless?
Not necessarily. The process of pulp death is often painful. A fully necrotic tooth may be temporarily symptom-free, but a subsequent periapical abscess can cause acute pain and swelling. ‘No pain’ does not mean the tooth is healthy.
My tooth stopped hurting. Does that mean it’s better?
Unfortunately not. When a tooth that was painful suddenly goes quiet, it often means the pulp has died, not that the infection has resolved. See a dentist for an X-ray to assess the root tip and surrounding bone.
What does a tooth nerve look like?
The pulp (commonly called the nerve) is a soft, pinkish tissue similar in appearance to the inside of a blood vessel. It runs from the pulp chamber in the crown down through narrow root canals. In a dead tooth, this tissue appears grey, brown, or black and has a characteristic unpleasant odour when accessed during root canal treatment.
Can a dead tooth cause headaches or sinus problems?
Yes. An abscess from an upper back tooth can push into the sinus cavity and cause sinus-like symptoms. A dead tooth can also cause referred pain that shows up as facial pain, headaches, or earaches.
If you’ve got unexplained sinus pain on one side along with a dental issue, it’s worth seeing your dentist.
