What is tooth gangrene ?

Last updated on: 5 Aug, 2026

Tooth gangrene is a condition in which the dental pulp (the nerve and blood vessels in the tooth) dies as a result of a bacterial infection, trauma or untreated tooth decay. The most common symptoms are severe throbbing pain, bad breath, swelling of the gums and an infection around the root of the tooth. 

Without prompt treatment, gangrene can lead to an abscess, damage to the jawbone and the spread of infection to surrounding tissues. It is one of the most serious complications in dentistry and requires immediate intervention by a specialist. 

In this article, we will look at what tooth gangrene is, what the main causes of its occurrence are, which symptoms you should not ignore, how the diagnosis is made, and what the modern methods of treatment and prevention are.

Image: freepik

Definition of tooth gangrene

Tooth gangrene is a pathological condition in which necrosis and putrefactive decomposition of the dental pulp occur as a result of a bacterial infection. Essentially, this is necrosis of the dental pulp – the soft core of the tooth, composed of nerves and blood vessels. 

When this dental pulp loses its blood supply and is attacked by bacteria, it breaks down and becomes necrotic. Gases are released, causing severe pain and an extremely unpleasant odour.

Unlike early-stage caries or reversible pulpitis, pulp gangrene is irreversible. It is an inflammatory condition in which the affected tissue gradually breaks down and, if not treated promptly, the infection spreads to the roots, the gum and even the bone surrounding the tooth.

Causes of tooth gangrene

The development of gangrene is rarely accidental. It is usually the end result of prolonged neglect of oral health issues or specific injuries. Here are the main causes of gangrene, classified into three groups.

Infections

Infection is the leading cause of necrosis in a tooth. Carious lesions, left untreated for a long time, gradually penetrate the enamel and dentine until they reach the pulp. There, the bacteria cause pulpitis, and in the absence of a timely response – gangrene. 

Mechanical, chemical and thermal causes can also open the door to bacteria. This can occur with repeated mild irritation from unsuitable filling materials or from hot drinks that damage the pulp. Once inside the pulp chamber, the microorganisms multiply rapidly and cause a purulent infection that destroys the living tissue.

Poor oral hygiene

Poor oral hygiene leads to the build-up of bacterial plaque and tartar. When teeth are not brushed regularly and properly, cavities develop; if left untreated, these lead to pulpitis, necrosis and, in the final stage, gangrene of the tooth.

Tooth trauma

Fractured teeth and physical blows to the face are another significant factor. Upon impact, the dental nerve may be severed suddenly, even without a visible broken crown. Such trauma cuts off the blood supply to the pulp, causing it to gradually necrotise. 

It is particularly worrying that with traumatic gangrene, symptoms may appear weeks or even months after the incident, as the process progresses slowly and painlessly at first.

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Symptoms of tooth gangrene

Gangrene does not always give immediate and obvious warning signs. However, the body sends out warning signals that you should pay attention to. Here are the most characteristic symptoms of gangrene.

Pain and discomfort

Pain is one of the first and most distinct signs of gangrene. It can range from sharp and throbbing to dull and constant. Interestingly, in cases of complete necrosis, the pain sometimes subsides and patients mistakenly believe that the problem has gone away. A tooth nerve affected by gangrene no longer responds, but the infection continues to spread. 

The absence of toothache when the tooth is stimulated may indicate a necrotic nerve, but severe, throbbing pain is usually a sign that the infection has spread to the surrounding tissues. Tooth sensitivity to hot and cold in the early stages of the condition is also a worrying sign that requires consultation.

Swelling and redness

As an infection in the oral cavity progresses, it can cause visible swelling of the gum around the affected tooth, and sometimes of the cheek. In more severe cases, an abscess – a pocket of pus around the affected tooth – may form. Such swelling should never be underestimated, as it requires urgent intervention by a dentist.

Unpleasant odour

The breakdown of necrotic tissue by bacteria is accompanied by the release of gases with a characteristic, unpleasant odour. Persistent bad breath that does not disappear even after brushing the teeth may be a symptom of advanced gangrene. 

Patients sometimes also notice an unpleasant taste in the mouth. Although there are many causes of bad breath, when combined with the other symptoms, it is a serious reason for an immediate visit to a specialist.

Diagnosis of tooth gangrene

Accurate diagnosis is key to choosing the right treatment approach. During a visit to a dental clinic, the specialist carries out a thorough examination, which includes a visual assessment, probing and tapping the tooth. An important role is played by the inclusion of an electrometric examination (electro-odontodiagnostics – EOD) – a method in which a weak electrical impulse is applied to the tooth to check whether the pulp reacts. 

X-rays are mandatory. They reveal the extent of root damage, the presence of a periapical abscess or bone resorption. The combination of clinical tests and imaging methods allows for an accurate diagnosis and the development of a personalised treatment plan.

How is tooth gangrene treated?

The choice of treatment depends on the extent of the damage and the patient’s general health. With timely intervention, the tooth can be saved through root canal treatment. 

This is an endodontic procedure in which the necrotic pulp is mechanically removed, the canals are cleaned, disinfected and sealed to prevent re-infection. Following successful endodontic treatment, a filling or crown is placed to protect the tooth.

If an infection is present, the dentist may prescribe an antibiotic for gangrene, usually from the penicillin group or metronidazole, depending on the type of pathogen. It is important to understand that the antibiotic does not replace treatment; its purpose is to limit the infection before or after the procedure.

In advanced cases, where the tooth is severely damaged and cannot be saved, tooth extraction is performed. Tooth extraction is a last resort, followed by a prosthetic plan – the placement of a dental implant or bridge.

Image: freepik

Prevention of tooth gangrene

Regular check-ups, at least twice a year, allow for the early detection of problems before they have progressed to necrosis. Timely treatment of small carious lesions prevents the infection from spreading to the pulp, as does good oral hygiene. When playing sport, particularly contact sports, it is recommended to use mouthguards to avoid traumatic injuries.

Possible complications

Delaying treatment for tooth gangrene is a dangerous decision. The infection can easily spread beyond the affected tooth and cause serious problems for the whole body. 

Main risks if gangrene is not treated in time:

• Periapical abscess – a build-up of pus around the tip of the root, causing severe pain and swelling.
• Phlegmon – spread of the infection to the soft tissues of the neck and face, potentially life-threatening.
• Osteomyelitis – bacterial infection of the jawbone, requiring prolonged and complex treatment.
• Sinusitis – in the case of upper teeth, the infection may affect the maxillary sinus.
• Sepsis – in rare but severe cases, bacteria enter the bloodstream and cause a systemic infection.

These complications highlight how important it is to act quickly at the first sign of any symptoms. A timely visit to a specialist can not only save the tooth but also prevent serious health complications.

Conclusion

Tooth gangrene is a serious but treatable dental condition if addressed in time. The key lies in regular dental care, frequent check-ups and seeking help promptly at the first warning signs. 

Put your trust in the Dentatime dental clinic, with its experienced team, state-of-the-art equipment and personalised approach, whether you need root canal treatment or a more complex procedure. Don’t wait until the pain becomes unbearable – your smile and your health deserve attention today.

Frequently asked questions

Can tooth gangrene go away on its own?

No, gangrene is irreversible destruction of dental tissue and will not go away without medical intervention. Delaying treatment only makes the situation worse.

Can a tooth with gangrene be saved?

Yes, with timely diagnosis and good general health, the tooth can be saved following root canal treatment and the fitting of a crown.

Is tooth gangrene contagious?

Gangrene is not contagious. It is an individual infectious process. However, the bacteria that cause tooth decay can be transmitted, but this does not automatically lead to gangrene in another person.