When I first got sick with Crohn's, my mouth was a hot bed of canker sores!
Nothing helped except sucking on ice chips. My parents thought that 1 or 2 might have been explained away as a bruise from brushing my teeth, but the most I had in my mouth at 1 time was 9! And they were in places you can't reach like right above my tonsils. I told my GI about that and she said the words 'aphthous ulcers' and that Crohn's effects Mouth to Anus, so I definitely think that these sores are Crohn's related and not due to any side effects from a drug. Once you're in remission, they'll go away or at least go back to normal, as in 1 or 2 here or there throughout the year.
Diagnosed with typical Crohn's at 16.
Got lucky with Asacol for a year, then even luckier with ten years of relative remission.
Now abscesses and fistulas are having an "atypical" Crohn's party around my junk.
Remicade is coming to get me soon!