I would definitely consult with a veterinary dentist before your vet attempts to use the dremel if he's never done it before. The teeth need to be planed at the correct angle or you could cause serious problems.
It may help in the long term if the problem is due poor diet and not due to genetic malformation. Is he getting a diet high in fiber now (with plenty of hay?)
We are as gods to the beasts of the fields. We order the time o' their birth and the time o' their death. Between times, we ha' a duty. - Terry Pratchett.
"Men have forgotten this truth", said the fox, "But you must not forget it. You become responsible, forever, for what you have tamed. - Antoine de Saint-Exupéry