Are There Any Dangerous Side Effects To Using Dexamethasone Oral

Are there any dangerous side effects to using dexamethasone oral rinse for a prolonged period of time? I find that it really helps with the many sores and lesions I constantly get on the inside of all parts of my mouth: inner cheeks, gums, tongue. I do see an oral surgeon regularly who has done a number of biopsies that have all been negative.