Microcirculation of human fetal tooth buds: a SEM study of corrosion casts

The microcirculation of tooth buds at the bell stage obtained from 5-month-old human fetuses was studied using corrosion casting and scanning electron microscopy. Each tooth bud has two independent vascular networks: one of the enamel organ and one of the dental papilla. Both systems are supplied by vertical branches of the inferior alveolar artery. The vascular bed of the enamel organ consists of capillaries relatively uniform in shape, forming a moderately dense network with irregular meshes. In contrast, the vasculature of dental papilla is extremely dense and its vessels show a sinusoidal character and signs of a vivid angiogenesis. The cast surfaces of capillaries in both vascular systems show the presence of tiny blebs probably representing extravasations of the casting medium through endothelial fenestrations.