Trench Mouth: Symptoms, Causes, and Treatment

Trench Mouth: Symptoms, Causes, and Treatment
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Trench Mouth: Symptoms, Causes, and TreatmentClinical Content Reviewed by Dr. Jay Khorsandi, DDS
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Table of Contents

  1. What Is Trench Mouth?
  2. Causes
  3. Symptoms
  4. Risk Factors
  5. Diagnosis
  6. Treatment
  7. Complications
  8. Prevention
  9. Outlook
  10. When to See a Doctor
  11. Frequently Asked Questions
  12. References

Trench mouth is a type of periodontal disease that causes swollen gums and a bad smell in the mouth.

The disease develops from gingivitis, an early form of gum disease, which stems from poor oral hygiene. Symptoms include bad breath and tender, swollen gums and painful gums that bleed easily.

Treatments, which must begin immediately to have much success, include scaling of your teeth, root planning and antibiotics.

What Is Trench Mouth?

Trench mouth is a type of periodontal disease that causes swollen gums and a bad smell in the mouth.

Also known as necrotizing ulcerative gingivitis (NUG), this painful oral condition dates back to World War I. It became common among soldiers due to the lack of access to dental care, poor oral hygiene and other challenges associated with life in the trenches. 

The condition is rare today, especially in developed countries. Regular visits to dental clinics and proper oral hygiene practices have led to drastically lower rates of trench mouth.

If you do develop trench mouth, your dentist can treat it using procedures such as scaling, root planing, antibiotics and regenerative surgery.


Trench mouth develops from gingivitis, an early form of gum disease. It is usually the result of poor oral hygiene. It progresses in four predictable steps:

  1. Failing to brush your teeth regularly allows plaque to form on your teeth.
  2. Plaque bacteria attack your gum tissue.
  3. Gingivitis develops, causing your infected gums to swell, become tender and bleed easily.
  4. Gingivitis progresses to trench mouth, causing gum ulcers, swelling and pain.


Symptoms of trench mouth include:

  • Bad breath
  • High body temperature (fever)
  • Tender, red, swollen gums
  • Crater-like sores between teeth
  • Painful gums
  • Severe gum bleeding with light contact, such as when brushing your teeth
  • A grayish substance along the gumline
  • A bad taste in the mouth

Gingivitis can progress quickly into trench mouth without warning. You should seek treatment as soon as possible after you experience the first symptoms of this disease.

Risk Factors

Some of the factors that may increase your risk of gingivitis and trench mouth include:

  • Tobacco use
  • Poor dental hygiene
  • Dry mouth
  • A weak immune system
  • Poor nutrition
  • Vitamin C deficiency
  • Diseases and medication that attack the immune system like HIV/AIDS and cancer drugs
  • Some viral or fungal infections
  • Poorly fitted dentures
  • Hormonal issues
  • Genetics
  • Stress


The symptoms of trench mouth overlap with those of many different dental diseases, so it can be difficult to diagnose. Your dentist may look for any of the following signs to confirm the diagnosis:

  • Medical and dental history
  • Gum pockets
  • Bone loss
Medical and Dental History
Your dentist may ask you questions about any past or current dental or medical issues that could predispose you to trench mouth. They may also refer you to a physician for additional testing, such as immune function tests.
Gum Pockets

The state of gum pockets (the spaces where your gums meet your teeth at the base of each tooth) is a reliable indicator of overall gum health.

To measure the pocket depth, your dentist will gently insert a probe into the area. Healthy pockets should measure 3mm or less. If you have pockets that measure 4mm or deeper, your gums are not healthy, and you may have trench mouth.

Bone Loss
Your dentist may use dental X-rays to examine sites with deep gum pockets for bone loss. This test can help assess any hard tissue damage that has occurred due to trench mouth.


Trench mouth must be treated as early as possible to prevent it from causing irreversible damage like bone loss and tooth loss. Treatment will also ease your discomfort and alleviate your symptoms. 

Treatment for trench mouth may include:

  • Scaling. This dental cleaning procedure removes bacteria and tartar, the hardened plaque that has accumulated on your teeth and under your gums.   
  • Root planing. During this procedure, your dentist uses lasers and other special tools to clean deep under the gums and remove tartar from the roots of your teeth. This may be necessary if your dentist cannot reach all of the tartar on your teeth using typical scaling techniques.
  • Teeth straightening. Teeth aligners or braces may be used to straighten any crooked teeth. This makes it easier for you to keep your teeth clean and protect your gums.
  • Custom-fit dental restorations. Poorly-fitting dentures, crowns or bridges may irritate your gums or facilitate plaque buildup. Correcting the fit of these restorations also corrects these problems. 
  • Antibiotics. Your doctor may prescribe these drugs to control any fever or inflammation due to your gum’s bacterial infection.
  • Pain relievers. Salt-water rinses and over-the-counter pain drugs can reduce gum soreness. To control severe discomfort, you may apply topical lidocaine on your gums.  
  • Regenerative surgery. This procedure may be necessary if you have an advanced case of trench mouth. It can help restore any jawbone tissue you have lost due to severe gum disease.


Untreated trench mouth can cause more serious health issues, including:

  • Periodontitis, which can permanently damage surrounding gum and jawbone tissue and may result in tooth loss
  • An increased risk of severe health problems like respiratory disease, heart problems, or stroke
  • Dehydration
  • Weight loss


Trench mouth can return after treatment, but certain lifestyle changes can help you prevent this from happening. These include:

  • Brushing your teeth twice a day and flossing once a day
  • Visiting your dentist for a dental checkup and cleaning at least once every six months
  • Getting treated for any condition that may weaken your immune system, such as leukemia
  • Avoiding smoking and irritants like spicy meals
  • Consuming a healthy diet to boost your immune system and overall health
  • If you’re on any medication that affects your immune system, discuss measures to prevent infection with a doctor who understands your condition and medical history


Trench mouth develops from a bacterial infection that you can easily manage or avoid with proper oral hygiene and preventive dental care. If you seek treatment as soon as possible, you should be able to get the condition under control and avoid more serious health problems.

When to See a Doctor

Your dentist can detect early signs of trench mouth during your regular dental checkups. However, seek medical help if you experience any gingivitis symptoms between appointments.

Seek immediate treatment if you experience a fever alongside gum ulcers or bleeding. You may have a severe and potentially life-threatening infection.

Frequently Asked Questions

Does trench mouth go away?
Trench mouth is treatable, but it doesn’t usually go away on its own. Left untreated, the bacterial infection can quickly spread and damage your gums and bone. You could lose your teeth as a result.
Are thrush and trench mouth the same?

Thrush and trench mouth are not the same disease. Thrush is a fungal disease, while trench mouth is caused by bacteria.

With thrush, white patches form on various parts of the mouth, including the tongue.

How do I know if I have trench mouth?
Recognizable signs of trench mouth include bad breath, ulcers and tender, swollen or bleeding gums. As the infection progresses, you may also develop a fever.


Necrotizing Ulcerative Gingivitis. (July 2017). Contemporary Clinical Dentistry.

Gingivitis. (August 2017). Mayo Clinic.

Gingivitis (Diagnosis & Treatment). (August 2017). Mayo Clinic.

Trench Mouth. (March 2022). MedlinePlus.

Oral thrush (Mouth Thrush). (July 2020). National Health Service.

Disclaimer: This article is intended to promote understanding of and knowledge about general oral health topics. It is not intended to serve as dental or other professional health advice and is not intended to be used for diagnosis or treatment of any condition or symptom. You should consult a dentist or other qualified healthcare provider with any questions you may have regarding a medical condition or treatment.