Bacteria can enter a tooth through a cavity, crack, or chip and spread until it causes an infection in the tooth pulp. A tooth abscess occurs when a bacterial infection in the tooth goes untreated until a pocket of pus builds up to try to prevent the infection from spreading. 

When a dental infection gets to the point that an abscess forms, it is a dental emergency that requires prompt care from an emergency dentist. If you have difficulty breathing or swallowing, call emergency services or head to the nearest emergency room.

An emergency dentist will drain the abscess and either perform a root canal to save the natural tooth or pull the tooth if it can't be saved. 

Symptoms

The main symptom of a dental abscess is a severe toothache. The buildup of pus that creates the abscess is usually very painful, and the tooth pain often does not respond to things that help mild toothaches, like over-the-counter pain relievers and warm saltwater rinses.

Your teeth may be sensitive to temperature or pressure from chewing if you have an abscess, and you may also have a fever from the infection. A tooth abscess can also cause your cheek or jaw to appear red and swollen. 

You may be able to see the abscess as a bump in the gums that resembles a pimple.

A tooth abscess that ruptures will release salty fluid with a bad odor into the mouth, and it usually helps relieve some of the pain. You still need to seek treatment if you have a tooth abscess that ruptures, even if the pain subsides.

Types

Dental abscesses can form in different areas of the mouth, depending on where and how the infection started.

Gingival Abscess

Many tooth abscesses, called gingival abscesses, form on the gum tissue around a tooth. Gingival abscesses are usually easy for emergency dentists to treat, especially if they're caught early. 

Periodontal Abscess

Periodontal abscesses are abscesses that form deep inside the gum pockets. 

These abscesses are harder to treat because there is nowhere for the pus to drain, which makes the infection more likely to spread. A gingival abscess can progress into a periodontal abscess if left untreated.

Periapical Abscess

Tooth decay wears away the outside layer of enamel and the first inner layer of dentin that helps protect the tooth pulp. Periapical abscesses usually form as a result of untreated tooth decay, which leads to an infection in the tooth pulp.