Fissure sealing is mainly suitable for deep fissures, so it is appropriate to do it once the tooth erupts and reaches the occlusal plane. Once the teeth are biting and chewing, the sockets are not as deep and can be self-cleaned, eliminating the need for socket closure. The indications for fossa sealing are deep grooves, especially teeth that can be inserted or snagged with probes. Fossa closure is indicated when the tooth erupts and reaches the occlusal plane. The most suitable age for sealing is 3-4 years old for milk molar, 6-7 years old for first permanent molar and 11-13 years old for second permanent molar. Once the teeth bite and chew, the grooves are not as deep and can be self-cleaning, so there is no need to seal the grooves. Whether you need to do fissure sealing, it is recommended to go to the hospital in time to consult a professional doctor.