The appearance of a small white or reddish bump on the gums—often painless—can go unnoticed. But when pus begins to drain from the bump, or it’s accompanied by a bad taste in the mouth, it’s time to act quickly. This is a gum fistula, a sign that an infection has developed around the tooth or root, seeking an outlet. This article explains what a dental fistula is, why it occurs, how it’s treated, and when immediate attention is required, including special considerations for children.
What is a gum fistula?
A fistula (lat. fistula) is a pathological channel that connects an internal source of infection in the tooth or jaw with the gum surface. In simpler terms, it is a natural “drain” through which the body tries to eliminate accumulated pus from the infected area.
It usually appears as:
• A small bump or pimple on the gums
• White, yellow, red, or flesh-colored
• Sometimes tender to touch, sometimes completely painless
• May discharge pus, clear fluid, or bloody exudate
A fistula is usually not a disease itself but a symptom of a more serious underlying condition, most often a pulp infection, granuloma, abscess, or chronic inflammation in the bone.
Why does a gum fistula appear?
A fistula forms as a result of an untreated tooth infection that has spread toward the root tip and surrounding bone. When inflammation becomes chronic, the body creates a channel to relieve pressure and drain pus.
The most common causes include:
• Deep cavities reaching the nerve, causing pulpitis
• Untreated granuloma at the root tip
• Tooth trauma leading to pulp death
• Tooth or filling fractures that allow bacteria into the tooth
• Poorly performed root canal treatment (incomplete cleaning)
• Periodontal disease—when the infection originates from the gum pockets, not the root
It’s important to note that even if the fistula opens spontaneously and pus drains out, that doesn’t mean the infection is gone. The problem is only temporarily “relieved” while the infection persists deeper inside.
Is a fistula painful?
In many cases, a fistula isn’t painful, precisely because it allows pressure from the inflamed area to escape. However, this can be misleading, as the absence of pain may cause patients to ignore the issue.
Pain can occur:
• Before the fistula forms, due to pressure inside the bone
• If the fistula doesn’t drain enough and the infection worsens
• In cases of an acute abscess that hasn’t yet “broken through” the surface
Regardless of the presence of pain, the appearance of a fistula always requires examination and treatment.
How is a gum fistula treated?
Treating a fistula isn’t just about removing the visible bump—the goal is to eliminate the source of the infection. Depending on whether the cause is in the tooth, bone, gums, or a combination, the dentist will choose an appropriate treatment approach.
The most common treatment methods include:
1. Root canal treatment (endodontics)
If the infection originates in the tooth root, the canals must be thoroughly cleaned and disinfected, dead tissue removed, and the tooth filled with a biocompatible material. This is the most common and effective way to eliminate infection and close the fistula.
2. Retreatment of a previously treated tooth (re-endodontics)
If the fistula appears on a tooth that was previously treated, the initial therapy may have been incomplete or unsuccessful. In such cases, canal revision is done, often with additional diagnostics like CBCT imaging.
3. Tooth extraction
If the tooth is severely damaged, the infection is widespread, and the tooth has no functional or aesthetic value, extraction may be necessary. Once removed, the body will clear the infection, and the fistula will close naturally.
4. Curettage and periodontal procedures
If the infection originates from the gums and supporting tissues, deep cleaning (curettage), pocket debridement, and periodontal treatment are performed.
5. Antibiotic therapy
In acute cases with swelling, fever, or systemic symptoms, the dentist may prescribe antibiotics, but only as a supplement, not a substitute for dental treatment.
What are the possible complications if a fistula isn’t treated?
Though a fistula may seem harmless, ignoring it can lead to serious complications, such as:
• Spread of infection to surrounding teeth or bone
• Development of a cyst or granuloma
• Bone resorption and tooth loss
• Infection spreading to the sinus (upper jaw)
• Infection of the surrounding soft tissue and potential abscess formation
• General health issues such as fever, fatigue, or even bloodstream infection (bacteremia)
Because of these risks, timely intervention is crucial to preserve the tooth and prevent complications.
Gum fistula in children – special attention
In children, fistulas most commonly appear due to deep cavities in baby teeth. Because of their structure, baby teeth are more prone to pulp infections. Children often don’t report pain, so parents may only notice a “pimple” on the gum.
Key characteristics of fistulas in children:
• Most often occur in the upper front teeth or lower molars
• Often go unnoticed because the child feels no pain
• The pus draining from the fistula often has a bad smell
• If untreated, it may affect the development of the permanent tooth
• Does not always require extraction – the tooth can often be saved with proper endodontic treatment
What should parents do?
• Never try to squeeze or open the fistula at home
• See a dentist as soon as possible—ideally, a pediatric dentist
• Don’t underestimate the situation just because the child isn’t in pain—absence of pain doesn’t mean absence of infection
Acting quickly can prevent infection from spreading to surrounding tissue, preserve space for permanent teeth, and reduce the need for future orthodontic treatments.
How to prevent a fistula?
Fistula prevention follows the same principles as preventing most dental infections: proper hygiene, timely diagnosis, and cavity treatment. Since fistulas often arise from long-term neglect, early action is the most important step.
Key prevention steps:
• Brush teeth twice a day with fluoride toothpaste, using proper technique
• Use dental floss or interdental brushes to remove plaque between teeth
• Attend regular dental check-ups—at least twice a year
• Treat cavities early—before they reach the tooth pulp
• Replace worn fillings and monitor previously treated teeth
• Supervise children, since they often can’t describe symptoms, and baby teeth decay faster
It’s especially important not to wait until pain increases or the fistula becomes visible, as these indicate changes that require more complex treatment.
When should you see a dentist?
The answer is simple: as soon as you notice a suspicious bump, discharge, or unusual sensation on the gums. Even without pain, bad breath, chewing discomfort, tooth discolouration, or a pimple on the gums are all signs that call for urgent dental evaluation.
At the appointment, the dentist will:
• Perform a clinical examination
• Take an X-ray (typically panoramic or periapical)
• Test tooth sensitivity
• Establish a diagnosis and develop a treatment plan
If the source of infection is clear and localised, treatment can begin immediately. In more complex cases, a specialist endodontist or periodontist may be involved.
Don’t Wait for It to Go Away on Its Own
A gum fistula is not a cosmetic issue or a temporary nuisance. It’s a sign that your body is trying to eliminate an infection, and that a serious dental problem is present beneath the surface. The sooner it’s detected and treated, the better the chance of saving the tooth and avoiding complications.
If you’ve noticed a fistula in yourself or your child, don’t wait. Early action means shorter, simpler treatment, while preserving the health of your teeth, gums, and jawbone.
The Esthea Polyclinic team is here for all types of diagnostics, treatment, and expert consultation. Our approach is personalised, professional, and focused on long-term solutions—without pain and delay.