DISTRIBUTION OF SODIUM IN THE TEETH AND BONES OF DOGS AS SHOWN BY THE RADIOACTIVE ISOTOPE

¹ Division of Dental Research, School of Medicine and Dentistry, The University of Rochester, Rochester, New York

Radioactive sodium was administered intravenously to 4 adult dogs and one young dog. Considerable variation was found to exist between the total Na²⁴ uptake of different animals but the ratios of radiosodium uptake by the various tissues within individual dogs, were fairly constant.

The Na²⁴ uptake by the maxilla, mandible, and femur were of a similar magnitude. No significant variation could be found in the radiosodium distribution of whole teeth from the same animal. The dentin gave values approximately twice that of enamel. Extraction of the organic part of whole tooth substance resulted in removal of 87 per cent of the labeled element. The maximum deposition of Na²⁴ did not take place in teeth until almost 12 hours following injection.