Dental Abscess: Recognizing and Treating a Tooth Infection

A dental abscess is a pocket of pus caused by a bacterial infection — and it's one of the dental conditions that should prompt an urgent call to your dentist. Unlike most dental problems that can wait for the next available appointment, an untreated abscess can spread to the jaw, neck, and even the brain, causing a life-threatening emergency.

Types of Dental Abscess

Periapical abscess: The most common type. Forms at the tip of a tooth root when bacteria from an infected pulp penetrate into the surrounding bone. Usually caused by untreated decay or a traumatized tooth.

Periodontal abscess: Forms in the gum tissue alongside a tooth root, typically as a complication of gum disease. The bacteria originate in a deep gum pocket rather than inside the tooth.

Symptoms

• Severe, throbbing toothache that may radiate to the jaw, ear, or neck
• Sensitivity to hot and cold temperatures
• Pain when chewing or biting
• Swelling in the face, cheek, or jaw
• Swollen, tender lymph nodes under the jaw or in the neck
• Fever (a sign the infection is spreading)
• A small bump (like a pimple) on the gum near the affected tooth — this is the abscess draining
• Sudden rush of foul-tasting, foul-smelling fluid in the mouth (the abscess has ruptured)

Treatment

Draining the abscess: Your dentist makes a small incision to drain the pus, providing immediate pain relief. The area is rinsed with saline.

Antibiotics: Prescribed when the infection has spread beyond the immediate tooth area, or when fever is present. Antibiotics alone do not cure a dental abscess — they manage the spread while the source (infected pulp or gum pocket) is treated.

Root canal treatment: For periapical abscesses, a root canal removes the infected pulp, eliminating the source of infection, and saves the tooth.

Extraction: If the tooth cannot be saved or treatment is not feasible, extraction removes the infection source entirely.

When to Go to the Emergency Room

Go to an emergency room immediately if you have: difficulty breathing or swallowing, swelling extending to the floor of your mouth, tongue, or throat, high fever, or confusion. These are signs the infection has spread to the airway — a life-threatening emergency called Ludwig's angina.