What can be done for sore mouth ulcers?

Mouth sores: It would be good to have your dentist take a look at the lesions to diagnose exactly what they are. Generally they last 7-10 days. Short term you can apply a over the counter ointment for canker sores/ulcers to numb it. It could be viral or bacterial or even from trauma or stress.

Topical numbing: First, there are many causes for mouth ulcers. These range from unknown through allergies, hot/spicy food or other things to cancer. If an ulcer has been present for more than two weeks it needs to be checked by a dentist. If ulcers come and go frequently then it may be possible to determine the cause and treat them. If they appear seldom and heal quickly then a toical anesthetic would help.