Oral Health Library · 9 min read
Muh Me Chale Kyu Hote Hain? Why Mouth Ulcers Happen
Mouth ulcers, often called muh ke chale, commonly happen after cheek biting, rubbing from a sharp tooth, or recurring inflammation of the mouth lining. Stress and low nutrient levels may contribute in some people. An ulcer lasting beyond two weeks, or with a lump, numbness, or unexplained bleeding, needs an in-person examination.
Written and medically reviewed by
Dr. Bipin R. Upadhyay
BDS · MDS Oral Medicine & Radiology · PhD Scholar · Associate Professor & Head, Department of Dentistry
Last clinically reviewed: 2026-10-26
Key points
- Mouth ulcers commonly follow minor injury or occur as recurring episodes with no single clear cause.
- Body heat, acidity, and nutrient deficiency should not be assumed to explain every ulcer.
- An ulcer lasting beyond two weeks needs an in-person examination.
- Lumps, numbness, unexplained bleeding, and difficulty opening the mouth or swallowing are warning signs.
- Care focuses on the cause, comfortable eating, gentle cleaning, and appropriate follow-up.
What are mouth ulcers?
A mouth ulcer is a sore where the thin surface lining inside the mouth has broken down. It may look round or oval, with a pale centre and a red edge. Even a small ulcer can hurt when you speak, eat, or brush.
Ulcers can appear inside the lips or cheeks, under the tongue, or elsewhere in the mouth. Their location, appearance, and healing pattern help a clinician understand the cause. A pale centre alone does not mean that the sore contains pus.
Not everything called a mouth ulcer is the same condition. Blisters, burns, white patches, and swollen gums can look similar to a family member. A photograph may help document a change, but it cannot replace examination when a sore persists.
- Notice when the sore first appeared.
- Check whether there is one sore or several.
- Observe whether each sore heals fully before another appears.
- Mention any nearby sharp tooth, filling, denture, or brace.
What commonly causes muh ke chale?
Minor injury is a common reason for a mouth ulcer. A bite during eating, a hard food edge, or rubbing from a broken tooth can damage the mouth lining. Very hot food or drinks can also burn the surface and leave a sore.
Another common pattern is recurrent aphthous ulcers. This means painful mouth ulcers that heal and then return at different times. Their exact cause is not always clear, and they are not simply caused by poor brushing.
Several factors may act together rather than one single cause. A person may have a tendency to develop ulcers, with stress or local injury helping trigger an episode. Some episodes have no obvious trigger.
- Accidentally biting the cheek, lip, or tongue.
- Rubbing from a sharp tooth, rough filling, brace, or loose denture.
- Recurring inflammation, meaning irritation and swelling within the mouth lining.
- Stress or disturbed sleep in some people.
- Low levels of certain nutrients in some people.
- Less commonly, an infection or another health condition.
Are mouth ulcers caused by body heat, acidity, or spicy food?
Many families describe mouth ulcers as a sign of body heat, or pet ki garmi. This is a familiar expression, but it is not a medical diagnosis. The cause still needs to be understood from the sore itself and the person's health history.
Spicy, sour, or very hot food can sting an existing ulcer. That does not prove that the food caused it. Some people notice particular food triggers, but avoiding many foods without a clear reason can make balanced eating difficult.
Acidity is not a general explanation for every mouth ulcer. Digestive conditions can sometimes occur alongside recurring ulcers, especially when there are other symptoms. Ongoing diarrhoea, abdominal pain, blood in the stool, or unexplained weight loss should be discussed with a doctor.
- Record foods that repeatedly seem linked to an episode rather than assuming all spices are responsible.
- Temporarily avoid foods that hurt the sore.
- Do not assume every ulcer means a nutrient deficiency.
- Persistent ulcers should not be dismissed as body heat.
Why do mouth ulcers keep coming back?
Recurring ulcers often begin in childhood or young adulthood, although they can happen at other ages. Small common ulcers usually heal within one to two weeks. New sores may appear later, sometimes in another part of the mouth.
An ulcer that keeps appearing in exactly the same place may be linked to repeated rubbing or biting. A sore that never fully heals is different from separate episodes of recurring ulcers. That distinction matters when deciding what examination is needed.
Frequent, large, or unusually painful ulcers may need a wider health assessment. Possible contributors include low nutrient levels, digestive disease, and conditions affecting the immune system, which protects the body. Occasionally, prescribed treatment for another illness may contribute; do not change it without speaking to the prescriber.
- Keep a simple record of dates, locations, and healing.
- Note whether ulcers interfere with meals, sleep, work, or school.
- Report fever, unusual tiredness, joint pain, skin changes, or sores elsewhere on the body.
- Mention a new pattern of ulcers, especially if episodes are becoming more frequent.
When does a mouth ulcer need an in-person examination?
Arrange an in-person dental or medical examination if an ulcer has not healed within two weeks. Do not keep trying home remedies while a persistent sore remains unexplained. Seek an earlier appointment if it is growing, repeatedly returning at one spot, or making eating difficult.
Most mouth ulcers are not cancer. However, an early mouth cancer can sometimes look like an ulcer, and pain alone cannot tell the difference. A painless sore also needs attention if it persists.
Tobacco and areca nut exposure make a careful examination especially important. Areca nut is also called supari and may be present in gutkha or pan masala. Mouth cancer can also occur in people who have never used these products.
- A non-healing ulcer beyond two weeks.
- A lump in the mouth or neck, or a firm area beneath a sore.
- Numbness of the tongue, lip, chin, or another mouth area.
- Unexplained bleeding.
- New or worsening difficulty opening the mouth.
- Difficulty swallowing or a persistent red or white patch.
- Seek urgent care if pain prevents drinking or there are signs of dehydration, such as very little urine.
- Seek emergency care for breathing difficulty, rapidly increasing swelling, or inability to swallow saliva.
What happens during a mouth ulcer examination?
The clinician asks how long the ulcer has been present and whether it has happened before. They also ask about dental injuries, other symptoms, tobacco or supari use, and existing health conditions. A list of current treatments can help.
The examination includes the ulcer and the rest of the mouth, not just the painful spot. The clinician may check teeth, dentures, the tongue, and the neck for swelling. They may gently feel the sore to assess its edges and the tissue underneath.
Many straightforward ulcers do not need tests. Blood tests may be considered when ulcers recur often or there are signs of a wider health problem. A persistent or suspicious ulcer may need a biopsy, which means taking a small tissue sample for laboratory examination.
- Bring earlier reports and photographs showing changes.
- Explain whether the sore fully heals between episodes.
- Mention weight changes, digestive symptoms, fever, or sores elsewhere.
- A biopsy recommendation does not automatically mean cancer; it helps establish the cause.
What does care for mouth ulcers usually involve?
Care depends on the cause rather than the appearance alone. If a sharp tooth or denture is rubbing the area, a dentist can address that source of injury. The sore then needs follow-up if it does not heal as expected.
For common recurring ulcers, care may include clinician-selected treatment to reduce discomfort and inflammation. If testing identifies a nutrient deficiency or another health condition, care focuses on that problem too. Large, frequent, or persistent ulcers may need specialist assessment.
Safe daily care aims to make eating and mouth cleaning more comfortable. It should not delay an examination when warning signs are present. Avoid applying harsh household substances or unknown powders, as these can burn the tissue.
- Choose soft foods that are comfortable to chew.
- Avoid very hot, sharp-edged, spicy, or sour foods if they sting.
- Drink enough fluids and seek care if drinking becomes difficult.
- Use a soft toothbrush and clean gently around the sore.
- Do not scrape, squeeze, or repeatedly touch the ulcer.
- Do not try to file a sharp tooth or adjust a denture yourself.
Can mouth ulcers be prevented?
Not every episode can be prevented. However, reducing repeated injury and recognising personal triggers may help. There is no single food or home remedy that reliably prevents all mouth ulcers.
Regular dental checks can identify sharp edges, broken teeth, and poorly fitting dentures. Gentle brushing and balanced meals support mouth health without assuming that every ulcer needs supplements. Keeping a regular sleep routine and finding manageable ways to reduce stress may also help some people.
Avoid tobacco and supari for wider mouth health, even if they do not seem linked to your ulcers. If ulcers remain frequent despite simple changes, seek assessment rather than adding more restrictions. The aim is to understand the pattern, not blame yourself for each episode.
- Have repeated rubbing or biting assessed.
- Record clear triggers without cutting out entire food groups unnecessarily.
- Keep track of healing rather than judging only by pain.
- Arrange review if the pattern changes or sores become more severe.
Who should you see for repeated or persistent mouth ulcers?
A dentist can assess common mouth ulcers and check for local sources of injury. An oral medicine specialist focuses on conditions affecting the mouth lining and related symptoms. A physician may also be involved when symptoms suggest a problem elsewhere in the body.
For readers around Mumbai and Ambarnath, Dr. Bipin R. Upadhyay practises at the Special Dental OPD, K.J. Somaiya Super Speciality Hospital, Sion, Mumbai, and Reasonable Smile Dental Clinic, Ambarnath. His qualification is MDS in Oral Medicine and Radiology.
A teleconsultation may help discuss symptoms and arrange the next step. It cannot replace feeling a lump, examining a persistent ulcer closely, or taking a tissue sample. Warning signs need an in-person examination.
- Book an examination for an ulcer lasting beyond two weeks.
- Seek earlier care for severe pain, frequent episodes, or difficulty eating.
- Report lumps, numbness, unexplained bleeding, and difficulty opening the mouth or swallowing.
Questions people ask
Muh me chale kyu hote hain again and again?
Recurring ulcers may reflect a tendency to develop inflammation in the mouth lining. Injury, stress, or low nutrient levels may contribute. Frequent episodes, unusually large ulcers, or other symptoms deserve an examination rather than assuming one cause.
How long does a normal mouth ulcer take to heal?
Many small common ulcers heal within one to two weeks. A sore that remains beyond two weeks needs an in-person examination, even if it hurts less. Seek care earlier if it grows or affects drinking.
Does every mouth ulcer mean a vitamin deficiency?
No. Injury and common recurring ulcers can occur without a deficiency. Blood tests may be useful when the history or examination suggests a nutritional problem. Not everyone needs testing or supplements.
Can mouth ulcers spread through sharing food?
Common recurrent aphthous ulcers are not contagious and do not spread by sharing food. Some infections can cause mouth sores that look different or similar. Sores with fever, blisters, or a rash may need assessment.
Can children get mouth ulcers too?
Yes. Children can develop ulcers after biting the mouth or as part of recurring episodes. Fever, several new sores, or a rash may suggest another cause. Seek prompt care if a child refuses fluids or passes very little urine.
Is a mouth ulcer a sign of cancer?
Most mouth ulcers are not cancer. However, a persistent ulcer can sometimes be an early warning sign. An ulcer beyond two weeks, a lump, numbness, unexplained bleeding, or difficulty opening the mouth or swallowing needs examination.
Why does an ulcer hurt when I eat spicy food?
An ulcer exposes sensitive tissue beneath the mouth's surface. Spicy or sour food can irritate that tissue and cause stinging. This does not necessarily mean the food caused the ulcer.
Can I wait if the ulcer is painless?
Lack of pain does not confirm that a sore is harmless. Arrange an examination if it lasts beyond two weeks. A growing sore, firm area, unexplained bleeding, or nearby lump needs earlier assessment.
This page is general information, not a diagnosis. A mouth problem needs to be looked at in person or on video before anyone can tell you what it is.