Who hasn’t had one of those nasty little burning wounds on your gums, the inside of the cheeks or the tongue?
Typically, they are canker sores or the result of accidentally biting the inside of your cheeks. And considering their size, they cause an unfair amount of discomfort. Normally, they should go away after a few days.
In Chinese medicine, anything that burns is considered Heat/ Fire.
The channels that mostly affect the mouth are the Stomach and Heart channel. As always in CM, the exact diagnosis varies from patient to patient. Though, if you have a bad digestion, it is rather likely that you suffer from Stomach-Fire: The Excess Heat rises to the top and affects the inside of your mouth.
Stomach-cooling acupuncture points and herbs should be administered to stop that Fire. After that, the root-cause of the Fire will have to be eliminated.