It is normal to be 7 and a half years old and not yet have a new tooth. Generally 6-12 years old belongs to the period of tooth replacement. There is a certain time and order for the loss of milk teeth, which should be lost without the completion of milk teeth, the consequence is often that the permanent teeth can not erupt in the normal position. Most children start to change their teeth at the age of 5-6 years, but there are some individual differences, some start at the age of 4 years, and individual children will delay the loss of the first milk teeth until the age of 7 years or so. Early or late tooth replacement is related to the child’s own development, some children develop earlier, some children develop later, and it is also common for children not to change their teeth at around 7 weeks of age. If you are concerned, you can take your child to the dentist for an oral radiograph. Through the whole mouth dental film can see the whole mouth teeth replacement situation, to determine whether the replacement will be carried out soon.