MadSci Network: Anatomy |
Dear Maddy, You ask a very good question, in fact the question is so good that there is no precise answer to it. Instead, there is a theory that seems like a good answer, but it has not as yet been proven to the satisfaction of all scientists working in the field. What most researchers believe is that the reason why people have two sets of teeth is because in children the mouth is much smaller than in the adult and therefore, children need smaller teeth to fit in the smaller jaws. However, as children become larger, their muscles also become larger and stronger, and those include the muscles that close the jaws. As these muscles gain strength they begin to be too powerful for the "baby teeth," and special cells, known as odontoclasts begin to remove the tooth from the tip of the root working toward the crown. As the baby teeth are being removed by these cells, the permanent teeth are being formed to replace the teeth being shed. I hope this helps. Leslie P. Gartner, Ph.D. Anatomy, OCBS Dental School University of Maryland Baltimore, Maryland
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