AbstractThe qualitative relationship of dental vascularity to mineralization of dentin and enamel was studied in 50 normal human fetuses 11.5 to 18 weeks of age, obtained unembalmed within 12‐24 hours after abortion. A 50‐50 suspension of India ink and 10% neutral formalin was injected manually into the umbilical vein (intact fetuses) or internal carotid arteries (autopsied fetuses), using sufficient pressure on the syringe to fill but not rupture nor overdistend the blood vessels. After immersion of the injected fetuses in 10% neutral formalin for three to five days, the maxillae and mandibles were removed and stained with alizarin red S for identification of calcium salts. Under magnification the dental sacs were exposed, removed intact and opened to observe: (1) the dental papilla, (2) its size and vascularity, and (3) the extent of mineralization of the crowns and cusps. Macroscopic preparations and microscopic sections were made of selected tissues from these specimens. The degree of mineralization appeared to be correlated more closely with the vascularity of the dental papilla than with the total size of the dental sacs, or that of the cusps or crowns. Blood vessels were present at the peripheral edge of both the developing enamel and dentin but no blood vessels were found to traverse the stellate reticulum nor were any blood cells found within it normally; whereas if abnormal pressure had been applied to the fetus or if the specimens were undergoing maceration, blood cells were observed within the stellate reticu
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