A periapical abscess is a pocket of infection around your tooth root. It happens when bacteria invade your tooth pulp, usually through a crack or cavity. The infection spreads down to the root of your tooth, causing inflammation and swelling.
A periapical abscess is a pocket of infection (pus) around your tooth root. This type of abscess forms when harmful bacteria from your mouth invade your tooth pulp. (This can happen if you have a cavity or a crack in your tooth.) The infection can spread all the way to the tip of the root and into the surrounding tissues.
Left untreated, a periapical abscess can spread to other parts of your body and cause serious, life-threatening complications. If you think you have an abscess, you should seek care immediately.
Periapical abscess symptoms may include:
Abscesses can also rupture (burst). If this happens, you may feel immediate relief coupled with a sudden rush of foul-tasting fluid. (This doesn’t mean the infection has gone away, though. You should still call a dentist.)
Most of the time, a periapical abscess causes discomfort. But some people never develop pain. If you have other symptoms — such as fever, bad breath or swelling — schedule an appointment with a dentist.
Bacteria cause a periapical abscess. Bacteria can enter your tooth pulp through a crack or cavity. The infection can then spread to the tip of your tooth root and into the surrounding tissues.
You’re more likely to develop a periapical abscess if you have:
Left untreated, a periapical abscess can spread to your jaw — and eventually, to other areas of your head and neck. In some cases, infection can even get into your blood and cause sepsis, a life-threatening condition.
Dentists use visual exams and radiographic (X-ray) imaging to diagnose periapical tooth abscesses.
A dentist will examine your teeth and gums. They may also tap gently on the affected tooth to see if it’s sensitive to pressure.
Your dentist will take dental X-rays of your abscessed tooth. These images can tell them how far the infection has spread.
In some cases, your dentist may request a CT (computed tomography) scan, especially if they think the infection may have spread to your neck. A dental CT gives your dentist a 3D view of your mouth.
Periapical abscess treatment depends on how far the infection has spread. Options include medicine and procedures, such as:
Dentists often prescribe antibiotics to keep abscesses from spreading further. It’s important to understand that antibiotics won’t keep the infection from coming back. You’ll still need to treat the tooth.
During this procedure, your dentist will create a small incision (cut) into the abscess. This allows infection (pus) to drain out. Next, they’ll flush the area out with a sterile saline solution.
In some cases, your dentist may place a small rubber drain in the incision. This allows any remaining infection to drain out over the next few days. (You may notice a strange taste in your mouth while the drain is in place.)
Your dentist may recommend a root canal to save your tooth. During this procedure, a dentist or endodontist makes a small hole in the top of your tooth. Using tiny instruments, they’ll remove the infected tooth pulp and drain the infection. Next, they’ll clean and disinfect the inside of your tooth, then place a rubbery dental filling material called gutta-percha. This seals your tooth and reduces your risk for further infection.
In many cases, you’ll also need a dental crown to protect your root canal-treated tooth.
Sometimes, it’s not possible to save an abscessed tooth. If the infection is too severe, your dentist may recommend a tooth extraction. During this procedure, they’ll carefully loosen the tissues around the affected tooth, then gently lift your tooth from its socket. They may also place a dental bone graft to reduce your risk of bone loss in your jaw.
You can’t prevent periapical abscesses altogether. But there are a few ways to reduce your risk:
There’s no hard and fast rule. It could take a few weeks — or sometimes, even months — for a periapical abscess to worsen. But putting off treatment can significantly increase your risk of developing serious, life-threatening complications, like sepsis.
If you have symptoms of a periapical abscess, you should schedule an appointment with a dentist right away. The sooner you treat the issue, the better chance of saving your tooth.
Seek emergency medical care if you develop:
If you have a periapical abscess, here are some questions you may want to ask your dentist:
The answer to this question is different for everyone. Some abscesses can form in just one or two days. Others may develop for weeks or months before you notice them.
If you notice any changes in your mouth or feel like something isn’t quite right, schedule an appointment with a dentist right away.
Though it doesn’t happen that often, it’s possible. Reinfection can occur if bacteria enter your tooth during treatment or if too much time passes before placing a crown. A root canal-treated tooth can also become reinfected if there’s a root fracture.
If this happens, your dentist may recommend a second root canal. Or they may recommend a tooth extraction.
Yes, if your abscessed tooth is close to your maxillary sinuses (the hollow space behind your nose), the infection could spread to your sinus cavity. That’s why it’s important to contact a dentist at the first sign of trouble.
A note from Cleveland Clinic
A periapical abscess is a pocket of infection that forms around your tooth root. Abscesses often cause pain, but they don’t always. If you think you could have a periapical abscess, it’s important to see a dentist immediately. Prompt treatment ensures that the infection doesn’t spread to other areas of your mouth and body.
Last reviewed by a Cleveland Clinic medical professional on 04/11/2023.
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