In this embryo, Meckel’s cartilage and the mandible converge anteriorly in a well-proportioned V; there is even a slight curve in both bone and cartilage at the transition to the dorsal third of its course (see Figs. 12.3 and 12.4). The bone of the mandible is so well developed vertically that the piston-shaped distensions of Meckel’s cartilage at its anterior ends are almost covered by bone. Both ends of the cartilage are touching in the symphysis and the bone formations come close to each other anteriorly to within 100 μm. The alveolar inferior nerve runs in a well-developed bone groove, the mental foramen is properly circularly closed (Figs. 12.1, 12.2, 12.3, and 12.4).