Short answer: Gum fungus, or oral thrush (oral candidiasis), is an infection that develops when the Candida fungi naturally present in the mouth multiply excessively. It can cause white patches that can be wiped off, redness, burning and cracks at the corners of the mouth. Wearing dentures, antibiotics, inhaled corticosteroids, diabetes and dry mouth increase the risk. It is treated with antifungal medications recommended by a doctor or dentist and by eliminating the underlying cause.
If you have noticed white patches on your tongue, the inside of your cheeks or your palate that leave a red surface underneath when wiped, cracks at the corners of your mouth, or redness and burning under your denture, the cause may be a fungal infection. Popularly known as gum fungus or oral fungus, the medical name of this condition is oral candidiasis. It occurs when Candida fungi, which are naturally present in the mouth, multiply excessively. In this article we explain the causes, risk groups, symptoms and treatment of oral thrush, and how it can be prevented, especially in people who wear dentures or aligners.
What is oral thrush?
Oral thrush (oral candidiasis) is an infection that develops when Candida fungi, which normally live harmlessly in the mouth, most often the species Candida albicans, multiply excessively because the balance has been disrupted. In a healthy mouth, these fungi are kept in check by bacteria and the immune system. When this balance is disrupted, the fungi multiply and cause an infection in the tissues of the mouth.
Although the term "gum fungus" is widely used, the infection is not limited to the gums; the tongue, the inside of the cheeks, the palate, the corners of the lips and the throat can also be affected. Oral thrush on its own is usually not a serious disease; however, it should be taken seriously because it can be a sign of an underlying cause.
Oral thrush has several common clinical forms:
- White plaque form: White patches on the tongue, the inside of the cheeks and the palate that look like curdled milk or cottage cheese and can be wiped off. When wiped, a red, tender surface may remain underneath.
- Red (erythematous) form: Redness and burning, especially on the palate and the top surface of the tongue. It can appear after long-term use of antibiotics or inhaled corticosteroids.
- Denture stomatitis: Redness on the area of the palate where a removable denture sits, matching the outline of the denture.
- Cracks at the corners of the mouth: Redness, cracking and sores at the corners of the mouth.
Causes and risk groups
Oral thrush is more common in conditions that weaken the immune system, disrupt the microbial balance in the mouth or create an environment favorable to fungal growth. The main risk factors are:
- Wearing removable dentures: Wearing the denture at night as well and not cleaning it well enough in particular make it easier for fungi to multiply under the denture.
- Babies and older adults: It is more common in babies because their immune system is still developing, and in older adults because of denture use and chronic illnesses.
- Antibiotic use: Broad-spectrum antibiotics can also reduce the beneficial bacteria in the mouth, paving the way for fungi to multiply.
- Inhaled corticosteroids: Inhaled medications used to treat asthma and COPD can build up in the mouth. Rinsing the mouth with water after use reduces this risk.
- Diabetes: The risk increases, especially if blood sugar is not under control.
- Dry mouth: When the protective effect of saliva decreases, fungi multiply more easily.
- Immunosuppressive conditions and treatments: Chemotherapy, radiation therapy to the head and neck, medications used after organ transplants and diseases that affect the immune system.
- Smoking and poor oral hygiene.
Symptoms
The most typical symptoms of oral thrush are white patches that can be wiped off, redness inside the mouth, burning and a change in taste; in some people the symptoms can be very mild. Possible symptoms include:
- White or cream-colored patches on the tongue, the inside of the cheeks, the palate or the gums
- Redness, burning and a sore feeling inside the mouth
- Sensitivity that increases especially with spicy and acidic foods
- A cottony feeling in the mouth or a reduced sense of taste
- Cracks and redness at the corners of the mouth
- In denture wearers, redness and tenderness under the denture
- In babies, refusing to feed and fussiness
Pain when swallowing or a feeling of food getting stuck may suggest that the infection has spread to the throat and esophagus and requires a doctor's evaluation. Not every white patch in the mouth is a fungal infection; white or red patches that cannot be wiped off, do not go away for a long time or feel hard should always be examined.
Treatment
Treatment of oral thrush includes clearing the infection with antifungal medications and eliminating the cause that set the stage for it. The treatment approach is determined according to the person's general health and how widespread the infection is.
- Diagnosis: In most cases, an examination of the mouth is enough for diagnosis. If necessary, a swab can be taken from the lesion for laboratory testing.
- Antifungal medications: For mild infections, medications applied inside the mouth in the form of gels, suspensions or lozenges are usually used. For more widespread or stubborn infections, the doctor may recommend medications taken by mouth. The choice of medication, the duration and the method of use should be determined only by a doctor or dentist; even if the complaints go away, treatment should be continued for the recommended period.
- Addressing the underlying cause: Bringing blood sugar under control, using the correct inhaler technique, treating dry mouth and correcting ill-fitting dentures are important for preventing recurrence.
- Treating the denture: For denture wearers, treating the tissues of the mouth alone is not enough; the denture must also be properly cleaned and disinfected. Otherwise, the infection can return shortly.
In cases of oral thrush that recur frequently or do not respond to treatment, a referral to the relevant doctor may be made to investigate whether there is a condition affecting the immune system.
Prevention for denture and aligner wearers
For people who wear dentures and aligners, the most effective way to prevent oral thrush is to clean these appliances regularly every day and give the tissues of the mouth time to rest. The surfaces of dentures and aligners can be porous at a microscopic level; on these surfaces, fungi and bacteria cling by forming a sticky layer called biofilm.
For removable denture wearers
- Take your denture out every day and brush it with a soft denture brush using soapy water or a denture cleaner. Regular toothpaste can scratch the denture surface.
- Unless your dentist tells you otherwise, take your denture out at night and let the tissues of your mouth rest.
- Rather than leaving the denture dry overnight, store it in a clean container as recommended by the manufacturer or your dentist.
- Gently clean your gums, tongue and palate with a soft brush.
- Have the fit of your denture assessed at regular checkups; dentures that rub or move can set the stage for tissue irritation and infection.
For clear aligner and night guard wearers
- Rinse your aligners with cold or lukewarm water every time you take them out; hot water can warp them.
- Brush your teeth before putting your aligners in; make sure no food debris is trapped under the aligners.
- Avoid drinking anything sugary or acidic, other than water, while wearing your aligners.
- Clean your aligners every day using the method your orthodontist recommends, and keep them in their case when not in use.
For detailed information on cleaning clear aligners correctly, you can read our article on how to clean clear aligners. At our clinic, clear aligner treatment is provided with the Invisalign system, and aligner care is explained in detail at the start of treatment.
When you notice a white patch in your mouth
If white patches or redness in your mouth do not go away within a few days, keep coming back, or if you experience burning and tenderness while wearing a denture, it is advisable to have an examination. At our polyclinic in Oran, Çankaya, in Ankara, the tissues of your mouth and any dentures or aligners you wear are evaluated together; when necessary, a referral to the relevant doctor is made.
Frequently asked questions
Is oral thrush contagious?
Since Candida fungi are already naturally present in most people's mouths, oral thrush is generally not considered contagious among healthy adults. However, in a breastfeeding mother, it can pass back and forth between the nipple and the baby's mouth. In this case, it is advisable for the mother and baby to be evaluated together.
Does oral thrush go away on its own?
When it is linked to a mild, temporary cause, for example after a short course of antibiotics, the symptoms may ease on their own. However, in most cases treatment with antifungal medications and correction of the underlying cause are needed. For patches that do not go away within a few days, you should see a doctor or dentist.
I wear dentures; what should I do to avoid getting thrush?
It is recommended that you take your denture out every day and clean it with a denture brush and a suitable cleaner, take it out at night unless your dentist tells you otherwise, and gently brush the tissues of your mouth as well. Having the fit of the denture checked regularly also reduces tissue irritation and the risk of infection.
How can inhaler users prevent oral thrush?
Rinsing your mouth with water and spitting after using inhaled medications containing corticosteroids reduces the buildup of the medication in your mouth. If your doctor considers it appropriate, using a spacer can also help. You should not stop your medication on your own.
