Are there different types of mouth ulcers?

Yes, the cause and the treatment differ by type. 1) Aphthous - the most common form, appearing as a white ulcer and usually healing on its own within 1 to 2 weeks. 2) Herpetic - a viral form with blisters that can be contagious and is treated with antiviral medication. 3) Candidal - a fungal infection with a white film that requires antifungal treatment. Whatever the type, an ulcer that does not heal within 2 weeks should be checked at the clinic.