Mouth ulcers are small lesions that appear at the bottom of your gums and other places in the mouth. They are usually white with red borders. They are not contagious and tend to disappear in 1 or 2 weeks. However, if an ulcer is hurting or does not go away for a long time then you should definitely get it checked.
Some people get mouth ulcers more commonly than others due to their genes. There is no specific cause of getting them. But there could be many triggers, including but not limited to:
Minor mouth injury- Injuries in the mouth can be because of accidental biting hard on anything, nail-biting, biting on pens or pencils or even brushing too hard.
Any sharp tooth that irritates you or any pricking sensation while wearing any appliance in the mouth eg. braces, dentures, mouth guards, etc.
Cleansing agent in toothpaste and mouthwash- some people can be allergic.
Sensitivity to acidic food like lemons, pineapples or other food triggers such as chocolate or coffee
Vitamin deficiency especially Vitamin B12, folate, zinc and iron
Allergies or infections
Stress, lack of sleep or hormonal change- stress hormones are one of the major factors for causing mouth ulcers. These are called stress ulcers.
Ulcers are also common in denture wearers due to the constant irritation of the oral tissues.

Ulcer in the mouth for a long time and painful ulcers can be a sign of a serious medical issue for example infections of the small or large intestines, improper digestion, severe acidity. A mouth ulcer can also be a sign of a compromised immune system in which the body fights against normal mouth cells instead of viruses and bacteria.
Mouth ulcers are seen in cases of STDs such as HIV/AIDS as well as some types of cancer. Ulcers in mouth cancer are rough, hard and spread to other areas. They persist for longer periods and are linked to longtime use of tobacco.
Home remedies for mouth ulcers
Most mouth ulcers are not a symptom of anything serious. But, there are a few home remedies you can check out to reduce their appearance and relieve pain.
•Apply a mixture of ghee+turmeric powder +honey and apply on the ulcer to sooth the irritated area.
•Apply milk of magnesia on the ulcer
•Rinse the mouth with salt water and some baking soda
•Use anesthetic gel containing benzocaine (Mucopain gel or Rexidine-M Forte gel available at pharmacies) for pain relief.
•Apply cooling products like ice or damp tea bags
•You can even drink cold milk or plain ice cream to relieve the burning sensations.
These remedies can reduce your discomfort and heal the ulcers faster. But if symptoms persist you should seek help from a doctor. They may prescribe you some supplements containing vitamin B12, Vitamin B6, zinc, and folic acid. If the ulcers usually do not subside by vitamin supplements the dentist might think of investigating further.
Here’s how you can prevent the appearance of oral ulcers by taking some precautions.
Avoid acidic fruits like lemon, orange, and pineapple as well as chips, spicy food and anything that can irritate the mouth. Start a healthy diet and ask your doctor for a daily multivitamin if you are prone to ulcers.
-Make sure your braces are not pricking you and try using a toothbrush with soft bristles.
-If you are stressed, try meditation and give importance to a full night of sleep each day. Try involving any activity you like to do to relieve your stress.
-Drinking plenty of water helps to reduce the frequency of mouth ulcers.
-The bottom line is, a mouth ulcer is nothing to worry about in most cases. Avoid irritating the mouth tissue and use home remedies if you are prone to them. If your ulcers hurt too much or stay for longer than a couple of weeks, seek medical help.
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