Deposition of Radioactive Strontium in the Developing Enamel and Dentin of the Rat

¹ Eastman Dental Dispensary, Rochester, New York

A study was made of the fate of radioactive strontium after deposition in the developing dental hard tissues of the rat. Once incorporated in the hard tissues, strontium⁹⁰ was not readily removed. The reduction of radioactivity, observed in autoradiographs and by direct counting, that occurred as the dentin became increasingly mineralized, was only apparent. The results of this investigation strongly suggest that physical self-absorption, due to increase in mineralization during development, which masks the radiation, is an important factor in accounting for this reduction.