After the root canal treatment of drug burn mouth ulcers, you can choose to temporarily observe, local medication, etc.. 1. Temporary observation: drug burns caused by mouth ulcers, you can temporarily observe, eat a light diet, do not eat spicy and stimulating food, after meals, salt water gargle, usually about 1 week ulcers will gradually heal. 2. Local medication: you can choose to apply iodine glycerin to the ulcer, or spray watermelon cream spray or ice boron powder to help the ulcer return to normal. 3. In order to avoid root canal treatment drug burns lead to mouth ulcers, in the root canal treatment must be strictly formal operation, to prevent the drug spillage caused by adverse reactions. Root canal treatment drug burns caused by mouth ulcers, do not treat yourself, timely to the hospital, under the guidance of a professional physician to choose a reasonable drug treatment, in order to facilitate the recovery of the condition.