Do you use mouthwash, teeth whitening products or a hard toothbrush? They are all known to cause gum or mouth irritation/burning.
In general, a salt water rinse is safer than mouthwash. Many mouthwashes have alcohol or similar ingredients that can cause irritation and burning.
A soft toothbrush is much better than a medium or hard one.
Are you having any other symptoms, such as a sore throat, red tongue, white coating on tongue or mouth? If so, it could be a viral, bacterial or candida infection.
Are your gums red, receding, or bleeding? If so, see a Dentist. It could be gingivitus, which can cause other health problems if not treated (including heart disease).
If it's a cold sore, there are some numbing solutions you can get from a drugstore.
