Clinically, there is no fastest solution for children’s mouth ulcers, which can be treated by adjusting the diet, maintaining oral hygiene and following the doctor’s prescription of topical medication. 1. Adjust the diet: During the period of mouth ulcers, it is recommended that children eat food rich in vitamins and light food, avoid spicy and stimulating food, which will affect the healing of mouth ulcers. 2. Maintain oral hygiene: children should pay attention to oral hygiene during the illness, brush their teeth on time every day, and rinse their mouths in time after meals, which is conducive to the healing of mouth ulcers. 3. Topical medication: Under the guidance of a doctor, you can use local medication to promote ulcer healing, such as oral ulcers, Guilin watermelon cream and so on. If the pain is more serious, you can use lidocaine gel to apply on the mouth ulcers to relieve the pain. When children’s mouth ulcers do not heal for a long time, please go to the hospital in time, the use of drugs need to be in the doctor’s advice, to avoid self-abuse of drugs.