For the young children with early appearance of multiple caries, who are caries susceptible, they can be treated with topical fluoride containing material in professional oral clinic from about 3 years old to reduce the occurrence of caries. Fluoride can enhance the anti-caries ability of teeth and its effect has been recognized worldwide. Nowadays, a variety of fluoride preparations have been widely used for caries prevention, such as: fluoride toothpaste, fluoride mouthwash, fluoride gel and fluoride foam, etc. Among them, the use of fluoride toothpaste and fluoride rinse is self-care; the use of fluoride gel and fluoride foam is professional care, which needs to be used by dentists in professional dental clinics. The commonly used materials for topical application of fluoride materials are fluoride coatings, fluoride gels and fluoride foams. Clinical experiment proves that applying fluoride gel twice a year can reduce the occurrence of dental caries by 26.3%. Many parents may worry that fluoride use may lead to fluorosis or dental fluorosis and other adverse consequences, but this is not too worry. Because this treatment is carried out by the doctor in the dental clinic, the dosage is well controlled and the doctor will decide the time and frequency of fluoride application according to the caries condition in the child’s mouth. Due to the high fluoride content in these materials, it is still necessary to reduce swallowing during application. The method recommended by the American Academy of Pediatric Dentistry is to apply for 4 minutes, followed by spitting out as much liquid as possible from the mouth within 1 minute and not eating or rinsing for half an hour. There is no strict age limit for this treatment, which is determined by the dentist based on the child’s oral condition. Most pediatric dentists believe that children around the age of 3 can routinely undergo fluoride application twice a year for caries prevention. Generally speaking, fluoride application on newly erupted teeth is more effective than other teeth in preventing dental caries. In addition, when using fluoride toothpaste at home, we should pay attention to the fact that children aged 6 and below are not yet able to swallow, so parents must supervise and guide them. Also, use a small amount of fluoride toothpaste, about the size of a soybean grain or 5mm in length, and preferably choose a children’s toothpaste with a lower fluoride content. Fluoride mouthwash should be used after consulting a doctor and strictly following the doctor’s recommended amount, making sure to spit out after 1 minute of rinsing and not eating or rinsing for half an hour. However, for safety reasons, the use of fluoride mouthwash is not recommended for children under 5 years old. Last but not least, parents should know that fluoride does not mean that the teeth will not occur again after fluoride treatment, but only enhances the anti-caries ability of teeth to a certain extent. What can really prevent tooth decay is “control diet and improve hygiene”.