The sudden growth of many mouth ulcers may be caused by poor rest. Staying up late for a long time, poor sleep quality or poor mental state, such as worrying and overthinking can easily lead to the occurrence of mouth ulcers. It may also be caused by eating problems, such as eating spicy and irritating food for a long time, which can easily lead to the occurrence of mouth ulcers. It may also be due to the lack of fresh vegetables and fruits for a long time, which may also lead to the lack of vitamins and trace elements, which will easily produce the symptoms of mouth ulcers. It is recommended that timely supplementation of vitamins and trace elements, and proper rest and outdoor exercise to ensure good rest and rest habits can improve body resistance and avoid the symptoms of mouth ulcers. The more mouth ulcers can also use drugs to promote healing, commonly used drugs are compound corticosteroids or can use tretinoin ointment for local application to promote its healing.