When deep decay, multiple dental procedures, or traumatic injury causes the soft tissue inside the tooth (the pulp) to become infected or inflamed, the infection will not resolve on its own. The pulp contains nerves, blood vessels, and connective tissue. The standard treatment to eliminate this internal contamination and save the natural tooth is endodontic therapy, commonly called a root canal. This procedure cleanses the infected pulp chamber and root canals, sealing them to prevent re-entry of bacteria. Choosing to forgo this treatment allows the infection to progress, transforming a localized dental problem into a significant health threat that affects both the jaw structure and the rest of the body.
Progression to Localized Abscess and Bone Destruction
If the infected pulp tissue is not removed, bacteria multiply rapidly within the confines of the tooth’s root canal system. These microorganisms eventually push past the root tip (the apex) and enter the surrounding jawbone tissue. This progression leads to the formation of a periapical abscess, which is a localized pocket of pus and debris that develops in the bone at the root tip. Symptoms can range from severe, throbbing pain and sensitivity to pressure, to visible swelling in the gums, face, or neck.
The presence of this chronic infection triggers a constant inflammatory response from the body’s immune system. As immune cells attempt to contain the bacteria, they release chemical mediators that begin to dissolve the surrounding bone structure. This process can manifest as a dental granuloma or a cyst, both of which erode the bone that provides structural support for the tooth. Over time, this localized bone destruction destabilizes the tooth, causing it to loosen and potentially shift its position within the jaw.
The unchecked bacterial spread can lead to osteomyelitis, a severe infection of the bone marrow and the surrounding bone. This condition is difficult to treat and can result in large-scale bone loss in the jaw. The pressure from the growing abscess may spontaneously drain through the gum tissue, sometimes appearing as a small, recurring pimple or fistula. While this drainage may temporarily relieve pain, it indicates the infection is actively spreading and establishing a pathway out of the bone.
Systemic Health Risks from Untreated Infection
The infection is not always contained to the area immediately surrounding the tooth; it can pose a risk to overall health by entering the bloodstream. Once the bacteria breach the local barrier, they can travel throughout the body, a condition known as bacteremia, leading to systemic inflammation. This inflammation can increase the risk of developing or worsening pre-existing conditions, particularly those involving the cardiovascular system.
Oral bacteria entering the circulation have been linked to an increased risk for endocarditis, an infection of the inner lining of the heart chambers or valves. Individuals with heart valve issues or artificial joints are particularly susceptible to this complication. Systemic inflammation caused by the chronic infection contributes to the formation of arterial plaque, increasing the risk of heart attack and stroke.
In acute scenarios, the infection can spread rapidly through the soft tissues of the face and neck. Facial cellulitis is a rapidly progressing soft tissue infection that causes significant swelling, which can compromise the airway and breathing function. A severe form, known as Ludwig’s angina, involves a rapidly spreading infection in the floor of the mouth that can quickly obstruct breathing, requiring immediate hospitalization and intervention. If the body’s response to the widespread infection spirals out of control, it can result in sepsis, leading to organ failure and death.
Irreversible Tooth Loss and Replacement Needs
The final consequence of neglecting a root canal is the irreversible loss of the tooth. If the internal structure of the tooth becomes too weakened by advancing decay, or if the supporting jawbone is too eroded by the chronic infection, the tooth cannot be salvaged and extraction becomes the only viable treatment option. At this stage, the goal shifts from saving the natural tooth to managing the damage and restoring function.
Extraction permanently solves the infection but introduces new challenges for oral function and aesthetics. The resulting gap requires subsequent restorative dentistry to prevent the surrounding teeth from shifting and to maintain the integrity of the bite. Replacement options include dental bridges, removable partial dentures, or a more invasive procedure like a dental implant.
These replacement procedures are often more costly, time-consuming, and surgically involved than the initial root canal treatment. Placing a dental implant, for instance, involves a surgical procedure to embed a titanium post into the jawbone, requiring a healing period before a prosthetic crown is attached. Treating the infection early with a root canal preserves the natural tooth structure, which is preferable to the complex and expensive process of replacement.