The usual signs are pain that lingers, sensitivity that outlasts the cold drink, tenderness when you bite down, and a tooth that has quietly changed color. Root canal therapy treats infection inside the nerve of a tooth, and catching it early usually means simpler treatment and a better chance of keeping the tooth.
Plenty of healthy teeth react to cold. The difference is what happens next. Ordinary sensitivity is sharp and then gone almost as soon as the cold leaves. Nerve trouble tends to hang on, throbbing for a while afterward. Pain that builds rather than fades is worth taking seriously, and so is a tooth that has started reacting to heat.
Every tooth has a hollow space running down the middle of it, holding nerve tissue and blood vessels. That tissue is what registers temperature and pressure. When bacteria reach it, the tissue becomes inflamed. Because it is sealed inside hard tooth structure, the swelling has nowhere to expand, which is why the pain can be wildly out of proportion to the size of the hole.
Once that tissue is infected, it does not recover. Cleaning out the inside of the tooth and sealing it is what stops the process, and it is what lets you keep the outer tooth instead of having it removed.
The warning signs, and why the pain can stop
- Sharp or throbbing pain that comes and goes, or that will not stop
- Sensitivity to hot or cold that lingers well after the stimulus is gone
- Pain when biting down or applying pressure
- Swelling or tenderness in the gums near one specific tooth
- A tooth that has darkened or discolored compared with its neighbors
- A small, recurring pimple-like bump on the gum
- Pain that wakes you at night, or that is worse when you lie down
- A bad taste or smell coming from one area of your mouth
- Decay that has worked its way through enamel and dentin to the nerve
- A crack or fracture that gives bacteria a path in
- A knock to the tooth, sometimes years earlier
- Repeated treatment on the same tooth over many years
- A large old filling that has begun to leak at its edges
One confusing part of nerve infections is that the pain can suddenly stop. Not because the problem resolved. Because the nerve tissue has died. The infection is often still present and can spread if it is left alone, so a tooth that was hurting last week and is quiet now is still worth getting checked.
Silence from a tooth is not the same thing as health. There is a separate post on this site about tooth pain that goes away on its own, and that is its whole argument.
Which signs need a same-day call
Some signs should not wait for a convenient appointment.
- Swelling of the gum, cheek, jaw, or face
- A fever alongside tooth pain
- Pain that over-the-counter painkillers no longer touch
- Drainage or a taste of pus coming from the gum
- A tooth that feels loose, or that suddenly meets the opposite tooth first when you close
Call us and describe what is happening. We prioritize dental emergencies and do our best to see patients the same day they call. If facial swelling is spreading, or you have any difficulty breathing or swallowing, go to the nearest emergency room first.
Untreated infections can spread to the surrounding bone and, in some cases, lead to a more serious abscess. MedlinePlus on tooth abscess describes the same path from an infected nerve to an abscess. The earlier it is addressed, the more likely the natural tooth can be saved rather than extracted. Waiting also has a way of turning a planned appointment into an urgent one, usually at the least convenient moment.
How the diagnosis is actually made
Symptoms point. They do not confirm. Teeth refer pain to their neighbors, and an upper molar and a sinus can feel much the same from the inside. So the diagnosis comes from testing rather than from where it seems to hurt.
- An exam of the tooth and the gum around it
- X-rays, which can show decay reaching the nerve and changes in the bone at the root tip
- Tapping the tooth, to see whether the ligament around the root is inflamed
- A cold test, comparing the suspect tooth against its neighbors
- A check of your bite, since one high spot can cause pressure pain with no infection involved at all
Sometimes the answer is that the tooth needs something much simpler. A cracked filling, a bite adjustment, or a cleaning for an irritated gum can produce similar symptoms. We would rather find that out than treat a nerve that was never the problem.
What the appointment involves and what follows it
- Local anesthetic, then a small opening made through the top or back of the tooth
- Removal of the inflamed or infected tissue from inside the root
- Cleaning, shaping, and disinfecting the canals
- Filling and sealing that space so bacteria cannot get back in
- A filling to close the access opening, temporary or permanent depending on the plan
Front teeth usually have one canal and back teeth have more, which is most of the reason some cases take longer than others. We will tell you what your tooth looks like on the images before anything starts, and how many visits your case is likely to need.
We use effective anesthesia, so you should not feel pain during treatment. What most patients actually notice is the time spent with the mouth open and something resting against the tooth. Afterward, soreness around the tooth for a few days is normal, especially when biting on it, and it usually settles with the aftercare we recommend. If it is getting worse rather than better, call us.
A treated tooth has had its inside hollowed out, which leaves it more brittle than it was. Back teeth carry heavy chewing load, so they are usually restored with a crown once the root canal is finished. Leaving that step undone is one of the more common reasons a treated tooth fractures later.
Front teeth are sometimes fine with a filling instead. It depends on how much sound tooth structure is left, which we can only judge once the decay is out.
When extraction is the better answer
Taking the tooth out is always an option, and it is sometimes the right one. Treating the nerve and keeping the tooth costs less than removing it and then replacing it with an implant or a bridge. Your own root also keeps the bone and gum around it in place. That is why saving the tooth is usually the first choice.
Extraction wins when there is not enough sound tooth left to restore, when a crack runs down into the root, or when a tooth has already been treated and has not settled. If that is your situation we will say so, rather than treating the same tooth twice and charging you for both.
How to get the tooth checked, and what the cost depends on
It depends on which tooth it is, how many canals it has, and whether a crown is needed afterward. Starting prices are on our pricing page, and your own figure is confirmed in writing at your consultation before any work begins. Financing options are available if you need to spread it out.
If any of this sounds familiar, do not wait it out. A quick exam and some imaging is usually all it takes to know exactly what is going on. Call (407) 774-4433 and tell us what the tooth has been doing.