Comparison of 33P with 45Ca distribution in developing rat molar enamel in vivo and in vitro

The distribution of 45Ca and 33P in developing rat molar enamel has been studied using freeze sectioning and autoradiographic methods. The distribution patterns of the two tracers in vivo were dissimilar. The use of in vitro methods showed that flux of 33P into enamel is not influenced by the cells of the enamel organ. It is suggested that the factors controlling movement of calcium and phosphorus into mineralizing enamel may be similar to those proposed for bone.