CHANGES IN THE TEETH AND JAWS OF NEONATAL WEBSTER MICE AFTER ADMINISTRATION OF NaF AND CaF₂ TO THE FEMALE PARENT DURING GESTATION

¹ (Department of Pathology, Yale University School of Medicine, New Haven, Conn.)

1. Administration of NaF and CaF₂ to the female parents during gestation caused changes in the structure of the jaws and teeth of the neonatal mice. Calcification of bone in the jaws was retarded. There was alteration of the cell structure of the ameloblasts, with retardation of the enamel matrix maturation. Cartilaginous-like formations appeared in the dental pulp. There was a bridging of the dentin matrix with these formations.

2. CaF₂ seemed to be more toxic to the fetuses than NaF, both by injection and by oral administration to the pregnant females.

3. Approximately 600 to 700 µg of CaF₂ and 1,000 to 1,200 µg of NaF were tolerated without causing resorption of fetuses or stillbirths; amounts in excess of this caused these phenomena.

4. In the cases of fluoride-treated animals, the pulpal blood vessels in the teeth of the newborn animals appeared to be hyperemic. There was disruption of the endothelial cells of the vessels, with slight hemorrhaging in the pulpal area as well as in the area immediately surrounding the tooth.