There are many diseases that can cause such problems as burning sensation on eating spices,additional symptoms are reduced mouth opening and regular ulceration of mouth.kindly visit a dentist/oral medicine doctor to evaluate the problem that you are going through.unnecessary use of any topical steroid is not advisable.
Next Steps
kindly visit a dentist/oral medicine doctor
Health Tips
keeping the mouth clean & quitting of any deleterious habits such as supari /pan masala chewing should be very helpful