Action of Fluorine on the Teeth of Rachitic Rats

Abstract

IN previous communications, it has been shown that the action of fluorine on the dentin of the rat's incisor tooth depends on the Ca: P ratio of the diet1. With low Ca: P ratio diets, fluorine causes a fine hypercalcified line in the predentin forming at the time of the injection, but on normal or high Ca: P ratio diets, this does not happen, and the effects of fluorine on the predentin are not seen until it starts to calcify. It was suggested that this difference was due to the differences in the blood calcium level, as this is low with low Ca: P ratio diets and normal or high with the other diets. This supposition has been tested in two ways: by raising the blood calcium of animals on the low Ca: P ratio diet, and by lowering the blood calcium of animals on the high Ca: P ratio diet, and observing the effects of fluorine after this has been done.