hello thanks for consulting at hcm..
did you have episode of
fever previous to that
canker sore??
it could also be due to recurrent apthous ulcers which occurs on the buccal mucosa,,you can also apply topical anesthetics such as mucopain to reduce the pain.. since already you are applying mouth sore treatment 4 times daily and also mouth washes,,it should suffice,,
how ever you could get coronoplasty-trimming of sharp teeth surfaces ,, since tongue is rubbing against the teeth,, it may help in faster healing,,it will take 5-6 days to heal,,
also try blowing air with mouth closed, so that teeth doent touch the tongue surface,,
Kindly consult a oral physician for a check up and treatment,,
hope it helps,, take care