Children usually start to replace their teeth around the age of 6, but due to individual development, some can be as early as 4-5 years old, or as late as 7-8 years old, which is normal. Under normal circumstances, the physiological loss of children’s first milk teeth occurs around 6 years old, if the body lacks the corresponding trace elements or nutrients, it may be delayed later, you can regularly go to the hospital for trace element testing, if there is a deficiency, it is recommended that under the guidance of the doctor timely supplementation. Secondly, during the period of tooth replacement, you need to keep your mouth clean and hygienic, and develop a good habit of brushing your teeth in the morning and evening and rinsing your mouth after meals. Avoid eating too hard food and reduce the intake of too sweet and sour food, and take appropriate calcium supplements or eat more calcium-rich foods such as milk, eggs and soybean products, which are beneficial to the healthy development of teeth and reduce the occurrence of tooth malformation or tooth decay. While taking calcium supplements, proper intake of vitamin C and vitamin D should be taken, which can promote the absorption of calcium. During the period of tooth replacement, parents should pay more attention to the growth and development of children’s teeth, and it is recommended to go to the pediatric dentistry department of the hospital regularly for checkups and timely treatment if there are any abnormalities.