Mouth ulcers can be divided into three main groups:
Canker sores
Herpes related mouth ulcers
Cancer or pre cancer ulcers
It's obviously very important to be able to sort out the difference between these groups.
Canker sores are short lived and usually cause stinging or pain inside the mouth. You can read much more about them and why they arise by following the links on this site.
Herpes mouth ulcers are more commonly found on the lips or at the edges of the mouth. They can appear on the gums or tongue but this is actually a bit less common.
Spotting the signs or symptoms of mouth cancer is incredibly important. Watch the video below for more information. Please don't ever be tempted to ignore the warning signs.