It may be normal to replace the lower incisors at the average age of 5. Every child grows and develops differently, so the timing of tooth replacement varies. Under normal circumstances, the time for children to change their teeth is about 6 years old, but there are some differences, some children may change their teeth earlier, about 5 years old will start to change their teeth, some children may be about 7 years old to change their teeth, this situation is a normal reaction. Usually need to pay attention to do a good job of children’s dental care health care work, it is best not to often stimulate the gums around, but also need to pay attention to the children’s diet, give the children to eat light and nutritious food to meet the children’s nutritional needs, but also can be appropriate to supplement the calcium material, can promote the development of teeth.