GRENZ RAY STUDIES OF THE CALCIFICATION OF ENAMEL

¹ School of Dental and Oral Surgery, Columbia University, N. Y.

An attempt was made to clarify the mechanism of enamel calcification. The old concept that enamel is laid down as a fully formed and calcified product is refuted by means of soft x-ray pictures. While the enamel is apposed in incremental layers its calcification is shown to pass through different stages en masse, confirming the work of von Ebner, Beust, Chase, etc.

One stage (under which the primary, young and transitional stages of von Ebner, are grouped) is radiolucent and insoluble in acid. A final stage is soluble in acid and radiopaque at 10,000 volts. The question of post-eruptive changes in enamel is discussed.