Organic-bound chromium in enamel, dentin, and bone studied by electron spin resonance

The present ESR investigation shows clearly that chromium is potentially present in the calcified tissues. With the use of the hydrazine-deproteinated procedure, it is suggested that chromium is associated with the organic constituent of the calcified tissues. The fact that the unheated tissues disclosed no chromium signal indicates either that the potentially present chromium is not paramagnetic, or that it is still paramagnetic, but the chromium signal cannot be detected because of a short relaxation time due to strong interaction with the organic materials.