Embryological Development of Human Molars

Dental development is a complex process by which teeth from embryonic cells grow and erupt into the mouth. It is governed by epithelio-mesenchymal interactions. The biological mechanism is the same for all teeth; however, epithelial signaling and homeogenous combinatorics are different from one type of tooth to another. The primary dental blade splits into the vestibular and primary dental blades opposite to the mesenchymal condensation. During dental development, three successive stages are described : bud, cup, and bell. The secondary dental blade responsible for the formation of germs in permanent teeth is formed from the primary dental blade in the bell stage. For the central incisor, lateral incisor, canine, first temporary molar, and second temporary molar, each primary dental blade gives rise to a single secondary dental blade for the corresponding permanent tooth. On the other hand, the primary dental blade of the second temporary molar will cause the formation of four secondary dental blades that will cause the formation of permanent germs of the second premolar, the first permanent molar, the second permanent molar, and the third permanent molar. The objective of this chapter is to focus on the cellular and molecular mechanisms explaining the normal development of molars by presenting the different current data and theories of science illustrating the human molar embryological development.