It is caused by your lack of vitamin B, and another reason is your oral bacterial infection. Anyway, remember to do the following two methods: 1 to ensure rest and avoid excessive fatigue. The diet should be nutritious, and complementary food should be added in time. Prevent partial eclipse and picky eaters, so as to avoid gastrointestinal dysfunction and malnutrition. (It is recommended to eat more fruits and vegetables)

2, to carefully check the teeth, tonsils and buccal mucosa for infection, once found to be treated in time. The oral cavity should be kept clean and hygienic. Brush gently from the back of the tongue for 1 ~ 2 times every morning to remove the exfoliated epithelium, and then rinse your mouth with 0.5% sodium bicarbonate solution, which can achieve remarkable results.