The initiation of tooth development is done at formation of Dental Lamina. This Dental Lamina shows rapid proliferation of cells in specific places to form Enamel Organ which proceeds with individual tooth development. Dental Lamina gives rise to all 20 deciduous teeth and by its distal extension to 12 permanent molars. A lingual extension from the Dental Lamina called Successional Lamina gives rise to all 20 succedaneous teeth. The stages of tooth development are based on the shape or morphology of enamel organ, hence called the Morphological Stages of Tooth Development. Let us study about the Bud stage. The oral ectoderm shows proliferation of cells into the connective tissue to form the Dental Lamina. The dental lamina then shows proliferation of cells to from the Enamel Organ. At this stage the enamel organ is just a round or oval localized growth of epithelial cells. As its shape is like a flower bud this stage is called as the Bud stage of tooth development. Like all epithelial structures, a basement membrane separates the Enamel Organ from the surrounding ectomesenchyme. Only two types of cells are seen in the Enamel Organ during the Bud stage. The Central cells which are polygonal in shape. And Peripheral cells which are cuboidal or low columnar in shape. Thus, in this stage morpho-differentiation of the Enamel Organ is seen but no histo-differentiation is seen in the cells. Which means that change in the shape of the enamel organ is noted, but the differentiation or specialization of cells of enamel organ is yet to be seen. As the Enamel Organ is formed the surrounding ectomesenchymal cells get closely packed around and below the enamel organ. This is known as 'Ectomesenchymal Condensation'. This is due to 2 reasons, increased mitosis of the cells near the enamel organ and migration of cells adjacent to the enamel organ. The area of condensed ectomesenchyme later forms Dental Papilla and Dental Sac, which form various parts of the teeth. But at this stage they cannot be distinguished as distinct parts.