If children’s teeth are properly coated with fluoride there will be no obvious bad effects, but if a larger amount of fluoride is applied, bad effects such as dental fluorosis and fluorosis may occur. In general, in order to prevent children from developing caries, fluoride can be properly applied to the teeth, which is good for children’s health and parents do not need to worry too much. However, if a large amount of fluoride is applied at one time and the child accidentally ingests fluoride, dental fluorosis may be induced, with symptoms such as change in tooth coloring and enamel loss. In severe cases, fluorosis will occur, manifested as skeletal proliferative, accompanied by nausea, vomiting, diarrhea, muscle cramps, chest tightness, laryngeal spasms, respiratory difficulties and other symptoms, which will seriously jeopardize the physical health of the child. If parents find that children’s teeth color changes significantly, and accompanied by abnormal physical discomfort, they should bring their children to the regular hospital in a timely manner, to carry out relevant examinations, to clarify the cause of the disease, and actively cooperate with the doctor to take relevant therapeutic measures. In daily life, we need to maintain children’s oral hygiene, to reduce the wear and tear of fluoride teeth.