Apical periodontitis is an inflammatory condition affecting the periapical tissues, which surround the tip of a tooth’s root. This inflammation represents the body’s defensive reaction to bacteria and their byproducts that have exited the root canal system of the tooth. It is a common dental issue that can lead to discomfort and, if left unaddressed, more significant health concerns.
The Root Causes of Infection
Understanding the causes of apical periodontitis begins with the internal structure of a tooth. Each tooth contains a pulp chamber and root canals, which house the dental pulp—a soft tissue composed of nerves, blood vessels, and connective tissue. This delicate tissue can become compromised, leading to infection.
The primary cause of infection is often deep, untreated tooth decay. When cavities progress, bacteria can penetrate the hard outer layers of enamel and dentin, eventually reaching and infecting the dental pulp. Once infected, the pulp often dies.
Beyond decay, other factors can lead to pulp infection. Dental trauma, such as a severe crack or chip in the tooth, can expose the pulp to bacteria or damage its blood supply, leading to its death. A previously performed root canal treatment might fail if bacteria were not eradicated or if the root canal filling’s seal becomes compromised, allowing reinfection.
Once the pulp is necrotic, bacteria multiply within the root canal system and can spread beyond the root tip into the surrounding jawbone. This bacterial invasion triggers an inflammatory response in the periapical tissues, leading to inflammation and bone changes.
Identifying Symptoms and Confirming Diagnosis
Symptoms of apical periodontitis vary depending on whether the condition is acute or chronic. Acute apical periodontitis often presents with noticeable discomfort, including severe pain when chewing or biting on the affected tooth. Individuals might also experience throbbing pain and visible swelling of the gums or face near the tooth.
In contrast, chronic apical periodontitis can be less obvious, often asymptomatic or causing only mild, intermittent discomfort. Sometimes, a patient might notice a small “pimple” or lesion on the gum tissue near the affected tooth, known as a sinus tract or fistula, indicating the body is attempting to drain the infection.
To confirm a diagnosis, a dentist performs several examinations. They may gently tap on the suspected tooth, a procedure called a percussion test, which often elicits pain if inflammation is present in the surrounding bone. The dentist also checks for any signs of swelling or tenderness in the gum tissue.
The definitive diagnostic tool is a dental X-ray. These images allow the dentist to visualize the bone around the tooth’s root tip. A characteristic sign of apical periodontitis on an X-ray is a dark shadow, or radiolucency, at the apex of the root, indicating bone loss due to inflammation.
Standard Treatment Approaches
Treating apical periodontitis primarily aims to eliminate the bacterial infection from the root canal system and allow surrounding tissues to heal. The most common treatment is non-surgical root canal therapy. This procedure involves creating an opening in the crown of the tooth to access the infected pulp chamber and root canals.
During root canal therapy, the infected pulp tissue is removed from within the canals using specialized instruments. The canals are then cleaned and disinfected with antimicrobial solutions. After disinfection, the canals are shaped and filled with a biocompatible material, typically gutta-percha, to seal them and prevent reinfection.
When non-surgical root canal therapy is not sufficient or has failed, surgical options may be considered. An apicoectomy, or root-end surgery, is a common procedure. This involves making an incision in the gum to access the bone around the root tip, removing the infected root tip, and placing a seal at the end of the root to prevent reinfection. The surrounding infected tissue is also removed.
If the tooth is extensively damaged, fractured, or has severe bone loss that makes preservation impossible, tooth extraction becomes the last resort. Removing the tooth eliminates the infection source. Following extraction, tooth replacement options, such as a dental implant or bridge, can be discussed.
Consequences of an Untreated Condition
Leaving apical periodontitis untreated carries significant risks, as the infection will not resolve on its own. The bacterial presence will continue to trigger an inflammatory response, leading to a progression of the condition. One common consequence is the formation of a painful dental abscess, a localized collection of pus within the bone or gum tissue.
The ongoing infection can also lead to the development of a periapical cyst, a fluid-filled sac that forms around the root tip. Both abscesses and cysts can cause substantial destruction of the jawbone surrounding the affected tooth, weakening the bone structure. This bone loss can compromise the stability of the tooth and potentially affect adjacent teeth.
Beyond localized issues, the infection can spread to adjacent tissues. This can result in widespread facial swelling, known as cellulitis, which can be painful and disfiguring. In severe cases, the infection can spread into the sinuses, causing sinusitis, or even enter the bloodstream, leading to systemic health issues like sepsis. Timely treatment is necessary to prevent these complications.