Study of the Distribution of Iodoantipyrine and Iodinated Albumin in Developing Teeth of Rats with Autoradiography

¹ Department of Physiology and Biophysics, Georgetown University School of Dentistry, Washington, D.C.

A technique was developed for investigating the circulation in developing teeth. One of two radioactive substances of widely differing diffusibility (iodoantipyrine and iodinated albumin) was injected into the dental circulation of young rats. Mandibular tissues were obtained for histologic study, from 5 seconds to 3 minutes after injection, and autoradiographs of sections made immediately. These same sections were then stained, using conventional techniques, and the two representations of the same section were then compared. These sections showed clearly the limits of the intravascular space in developing teeth. However, they showed an extremely effective exchange of diffusible substances between the systemic circulation and the water of the hard dental tissues. Finally, they indicated the absence of an exchangeable albumin pool in these areas.