Mouth ulcers white stuff is not recommended to pick off. 1. Mouth ulcers have a layer of white film, called pseudomembrane, is a layer of mucous membrane to protect the membrane, is conducive to the protection of the wound is not infected. If you pick it off, it is easy to cause the wound place to appear secondary infection or delay the improvement of the disease, so it is recommended not to pick off. 2. Mouth ulcers are a kind of self-healing oral disease generally 3~7 days can be self improvement. Usually you can try to use mouth ulcers, watermelon cream treatment, is conducive to promote the ulcers to improve as well as relieve the pain. Specific medication should be under the guidance of a doctor. During the period of mouth ulcers, avoid eating spicy and stimulating food, eat more fresh vegetables and fruits, drink more water, and maintain oral hygiene.