抄録
The vascular system in the rat upper incisor and its development were observed in black ink injected and cleared specimens of various ages of postnatal growth, and the following results were obtained: 1) Arteries leading to the incisor come from the labial and palatine sides and connect with a regular capillary network lying external to the outer enamel epithelium. The capillaries unite at the lower border of the enamel organ and join a rich venous plexus surrounding the tooth bud. The veins arising from the plexus connect with the angular and anterior facial veins. 2) With the postnatal growth the capillary network in the outer enamel epithelium begins to show a distinct regularity, while the venous plexus surrounding the capillaries from the outside extends widely to cover the enamel organ and the posterior half of the incisor. 3) The pulpal blood vessels greatly elongate and increase in number with age. Capillaries invade the odontoblastic layer except in the posterior region where the odontoblasts are arranged regularly. In addition to these descriptions, some discussions are made on the functional significance of the capillary network and the venous plexus.
