What is a root canal?
A root canal is an infection of the soft center of the tooth, known as the pulp. The pulp is composed of nerves, connective tissue, and blood vessels that aid in the growth of the tooth [1]. This may become infected as a consequence of untreated cavities, inflammation due to repeated dental procedures, or trauma such as a cracked tooth exposing the pulp to bacteria.
The root canal procedure
The root canal treatment (endodontic therapy) aims to eliminate the infection and preserve the outer structure of the tooth. Briefly, the procedure is done as follows:
- The tooth and surrounding areas are numbed with local anaestesia;
- A protective barrier is placed around the infected tooth;
- The infected pulp is accessed by drilling through the enamel, and the infected tissue is cleaned out. If there is any old material such as fillings or crowns in the tooth, this is also removed;
- The infected area is treated with antibiotics;
- Once the area is dried out, it is filled with a filler (amalgam or composite), and the tooth may be fitted with a permanent crown to protect from future infections [2].
Success of the root canal procedure
Root canal is a common procedure that can save a tooth from extraction, and prevent serious complications including infections or abscesses. As with any other procedure, there is always a risk of an adverse outcome.
Overall, the procedure is safe and successful. A study in England and Wales found that an estimated 74% of root canal-treated teeth survived without further treatment for up to 10 years [3]. A similar study in Sweden reported a slightly higher 10-year survival rate of treated teeth of 81.7% [4]. In South Korea, the 11-year cumulative survival rate for non-surgical root canal treatment was 88.37% [5].
The largest factor influencing success of the procedure appears to be expertise of the medical provider. One study found that molars treated by endodontists (dentists who specialise in the procedure) had a 5% higher survival rate at 10 years compared to those treated by non-endodontists [6].
Can you die from root canal?
An untreated root canal can lead to several complications. Some of these can be fatal. It is therefore important to take care of your dental health and get any cavities treated as soon as possible.
Here, we review some of the biggest risks:
Abscesses
An abscess is a fluid-filled cyst developing as a consequence of an active infection. This can occur either if the infection is untreated, or some active infection is left behind during the root canal procedure. Antibiotic resistance is also a culprit of this, as the antibiotics may not be effective at treating a resistant infection. Tooth abscesses can be fatal if untreated, with some sources stating mortality up to 45%.
Sepsis
Sepsis is a life-threatening condition where the body over-reacts to infection so aggressively that vital organs are injured. The risk of sepsis increases as the bacteria get from the primary infection site (the tooth in this case) to the bloodstream.
The mortality of sepsis varies, however, severe cases can reach between 25% to 30% in mortality. The most extreme cases of sepsis, septic shock, can be fatal in up to 50%. The treatment of sepsis relies on early intervention, resuscitation with fluids to stabilise the cardiovascular and respiratory functions, and aggressive treatment of the infection with appropriate antibiotics. However, it is important that even after sepsis is resolved, patients can continue to face long-term disability, such as cognitive and functional deficits.
Gangrene
Gangrene is another serious condition which can arise as a result of a tooth getting infected. It develops when tissue dies due to lack of blood supply, or as a result of bacterial infection. While typically common on the extremities, gangrene can develop in the mouth or on the gums as a result of an untreated tooth infection. If untreated, gangrene can lead to sepsis or septic shock. The mortality of gangrene depends on the severity of the condition. However, broadly, in a study of patients with infectious gangrene, the 5-year survival rate was 40%. Some advanced forms of gangrene can have an overall mortality reaching 25%.
Gangrene is treated by antibiotics to resolve the infection, however, most important is debridement. This refers to removal of the infected or dead tissues, followed by reconstruction using for example a skin graft (when skin is involved, for example on the limbs). However, this is more complicated in the mouth, and more aggressive removal of tissue may be needed.
Summary
Untreated root canal can be fatal, with complications such as development of abscesses, gangrene and sepsis reaching mortality up to 50%. It is therefore important to visit the dentist regularly and get cavities repaired as soon as possible so that they don't progress to root canal.