RELATIONS BETWEEN MECKELS CARTILAGE AND THE MORPHOGENESIS OF THE MANDIBLE IN THE HUMAN EMBRYO

Based on a series of human embryos classified in stages [28], the auth ors studied the evolution of Meckel's cartilage in its ventral portion and its relations to the morphogenesis of the mandible. Three stages appeared particularly important: stage 16, appearance of Meckel's cart ilage; stage 20, beginning of membranous ossification; and stage 23, e nd of the embryonic period (8th week). The primitive bony nodule which develops from the embryonic mesenchyme appears as a double bony layer forming a groove containing the neurovascular bundle, into which the dental lamina is also invaginated.