What are the signs that a root canal is needed?

At times there may be no signs that you notice. This is why it is best to have regular check-ups to try to avoid problems before they become acute emergencies. Often there may be evidence on radiographs (x-rays) of a chronic infection at the tip of the tooth or decay which is either into the pulp or very near it. Both of these conditions are indications for root canal treatment prior to an emergency. DON'T WAIT TILL IT HURTS.

Root canal treatment or endodontic therapy is often the indicated treatment when someone has a toothache. The symptoms are spontaneous pain, lasting sensitivity to cold which is then relieved by heat in the earlier stage of pulpal deterioration and lasting sensitivity to heat which is relieved by cold in later stages of pulpal degeneration. As the pulp ("nerve area") dies an abscess may form which creates pain on biting and touch, tenderness to palpating tissue near the involved tooth and possibly swelling. This is due to the infection at the tip of the tooth. 

Also, there are situations when a tooth has an extensive large filling and requires a crown. In this case it may be indicated to electively have the endo treatment performed prior to the crown services.
Usually, the first sign you'll notice is pain in the tooth -- pain that gets progressively worse. But sometimes a tooth that needs a root canal doesn’t give you any pain. So to be honest, it's hard to nail down to a specific symptom. But I *can* say pain is a good indicator. Swelling/abscess is a dead giveaway as well (but that's pretty obvious.)

If you have tooth pain, call your dentist and let him or her let you know what remedies are available (which may include root canal).
Romesh Nalliah

The following are the most important symptoms that indicate a root canal may be needed:

  1. Pain in response to hot and cold triggers that is severe
  2. Pain is response to biting or chewing pressure
  3. Pain that lingers for more than 10 seconds
  4. Pain that starts with no specific trigger

A toothache or swelling could indicate that a tooth needs a root canal. If you have these symptoms you should see your dentist. An exam and x-ray of the tooth will help the dentist decide if your tooth needs a root canal. Sometimes teeth that do not hurt also need root canals. These teeth can be diagnosed with dental x-rays.

Severe unstimulated pain. Extreme sensitivity to hot or cold that lasts for 15 minutes or longer. Swelling in the gum around the tooth. Tooth hurts to bite on. Tooth feels higher than the rest of the teeth (the first or only tooth to touch when trying to bite teeth together.

The most common sign is frequent and intense pain, however a tooth can "die" (the pulp can become necrotic or infected) without pain. When teeth have been chronically infected a dental x-ray reveals bone loss at the apex or root tip. If left untreated this bone loss will eventually spread around the entire root until the tooth becomes loose. Common signs that a root canal is necessary are

  1. Spontaneous pain
  2. Tenderness at the root apex
  3. Tenderness to percussion or tapping on the tooth
  4. Tenderness to bite on the tooth.

The most frequent type of symptom that usually needs root canal treatment is sharp shooting pain that keeps you up at night. Other signs are lingering type of pain when something hot or cold touches the tooth or pain to pressure. A recurring or persistent pimple in the gums or a swelling in the jaw or gums near the tooth affected may also indicate a need for Root Canal treatment. It is also possible to have no pain. A discoloration in the tooth may indicate a need for root canal treatment. Frequently, teeth that have been traumatized don't discolor until much later. It could be days, weeks, or years for a tooth to discolor from trauma. It is best to see your dentist regularly for prevention and early detection.           

If you have pain when biting, tooth sensitivity to heat or cold, gum swelling near a specific tooth, tooth discoloration, or a broken tooth, you might need a root canal. Your dentist can do some easy tests to determine whether you need a root canal, such as putting something hot or cold next to the tooth or taking an x-ray of the tooth.

You might need root canal when there’s an infection in the tooth or the tooth’s pulp is damaged. The pulp can get infected from an untreated cavity. This happens if the pulp, inside the tooth, becomes exposed to bacteria, causing inflammation and reducing the tooth’s blood supply. Antibiotics can’t reach inside a tooth to clear up an infection, so the pulp needs to be cleaned out and the root canal filled. If you're experiencing pain or sensitivity in a tooth, especially in a tooth that's broken or cracked, you may have root or pulp damage and should see your dentist immediately.`
If you are experiencing pain when you have hot or cold foods and drinks, or if it hurts to bite down on your tooth, a root canal may be required. A tooth that needs root canal will sometimes discolor, have pain and swelling around the gum line, or wake you up at night.

Continue Learning about Root Canal Therapy

What may happen before a root canal treatment?
William M. Litaker Jr., DDSWilliam M. Litaker Jr., DDS
Before root canal treatment an x-ray will be taken of your tooth. Your tooth will also be numbed wit...
More Answers
What medications will I need for a root canal?
William M. Litaker Jr., DDSWilliam M. Litaker Jr., DDS
For most root canals only a local anesthetic is needed to numb the tooth. Anxious individuals may be...
More Answers
What are some complications of root canal treated teeth?
William M. Litaker Jr., DDSWilliam M. Litaker Jr., DDS
Teeth that have root canals are more brittle than other teeth. Back teeth should have crowns placed ...
More Answers
How successful are root canals?
Mark A. Wisniewski, DDSMark A. Wisniewski, DDS
Root canal success has been a topic of recent debate. Until recently a dentist has been forced to us...
More Answers

Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.