The most common ways of calcium supplementation for 7 year olds during tooth replacement are calcium supplements and dietary supplements, etc. There is no “best” way, and the right way should be chosen according to the specific situation. Children’s need for calcium increases during the rapid growth period. Insufficient calcium intake may lead to calcium deficiency, which in turn may adversely affect normal tooth replacement and bone development. If, after professional counseling, calcium supplementation is needed, the most direct way to supplement calcium is to take calcium tablets. If a child has not been medically diagnosed with a calcium deficiency, but is just concerned about the effects of a calcium deficiency on tooth replacement and would like to take a preventive calcium supplement, he or she can consume foods high in calcium, such as milk, soybeans and their by-products. And do more outdoor activities so that children can produce more vitamin D3 on their own to promote calcium absorption.