Merck Manual

Please confirm that you are not located inside the Russian Federation

honeypot link



Bernard J. Hennessy

, DDS, Texas A&M University, College of Dentistry

Last full review/revision Mar 2021| Content last modified Mar 2021
Click here for the Professional Version

Pulpitis is painful inflammation of the tooth pulp, the innermost part of the tooth that contains the nerves and blood supply.

The most common cause of pulpitis is tooth decay, and the second most common cause is injury. Mild inflammation, if relieved, may not damage the pulp permanently. Severe inflammation may cause the pulp to die.

Pulpitis may lead to infection, in which a pocket of pus (periapical abscess) develops at the root of the tooth. An untreated infection in a tooth may spread to the jaw or to other areas of the body (such as the brain or sinuses).

A Look Inside a Tooth

Symptoms of Pulpitis

Pulpitis causes intense tooth pain. If an abscess is present, the tooth becomes extremely sensitive to pressure and tapping with a dental instrument.

Diagnosis of Pulpitis

  • Testing tooth for sensitivity

  • Testing pulp for vitality with an electric pulp tester

To determine whether the pulp is healthy enough to save, dentists can do certain tests. For example, dentists can apply a hot, sweet, or cold stimulus. If the pain goes away within 1 to 2 seconds after the stimulus is removed, the pulp may be healthy enough to be saved (called reversible pulpitis). If pain persists after the stimulus is removed or if pain occurs spontaneously, the pulp may not be healthy enough to save (called irreversible pulpitis).

Dentists may also use an electric pulp tester, which indicates whether the pulp is alive but not whether it is healthy. If the person feels the small electrical charge delivered to the tooth, the pulp is alive. Sensitivity to tapping on a tooth often means that inflammation has spread to the surrounding tissues. Doctors sometimes do x-rays to evaluate the bone around the tooth for changes related to inflammation of the pulp such as a cyst or inflammation of the bone itself.

Treatment of Pulpitis

  • Removal of cavities

  • Restoration of tooth

  • Sometimes root canal treatment

  • Sometimes antibiotics

The inflammation stops when the cause is treated.

In reversible pulpitis, pain and inflammation go away after dentists remove any decay (cavities) and then restore the tooth. When pulpitis is detected early, dentists sometimes place a temporary filling containing a sedative that can eliminate the pain. This filling can be left in place for 6 to 8 weeks and then replaced with a permanent filling. Most often, dentists place a permanent filling immediately.

In irreversible pulpitis, pulp damage is extensive and cannot be reversed. The only way dentists can stop the pain is by removing the pulp via root canal treatment or tooth removal (extraction). If people have other signs of infection (such as a fever), dentists may give antibiotics taken by mouth. Sometimes root canal treatment is repeated if the symptoms do not go away or worsen.

More Information

The following is an English-language resource that may be useful. Please note that THE MANUAL is not responsible for the content of this resource.

  • Mouth Healthy: This general resource provides information on oral health, including nutrition and guidance on selecting products that carry the American Dental Association's seal of approval. There is also advice on finding a dentist and how and when to see one.

NOTE: This is the Consumer Version. DOCTORS: Click here for the Professional Version
Click here for the Professional Version
Others also read

Test your knowledge

Recurrent Aphthous Stomatitis
Recurrent aphthous stomatitis (canker sores) is the presence of small, painful sores (ulcers) inside the mouth. The ulcers typically first appear in childhood and recur frequently throughout adulthood. Which of the following is usually the first symptom of an attack? 
Download the Manuals App iOS ANDROID
Download the Manuals App iOS ANDROID
Download the Manuals App iOS ANDROID

Also of Interest

Download the Manuals App iOS ANDROID
Download the Manuals App iOS ANDROID
Download the Manuals App iOS ANDROID