Electron paramagnetic resonance study of irradiated tooth enamel

In the inorganic hydroxyapatite matrix of tooth enamel a new stable radiation damage ${\rm CO}_{3}^{3}-$ has been found with $g_{\perp}=2.0036$ and $g_{\parallel}=1.9983$. The origin of the H atom centers is bound to the hydroxyapatite OH- ions. Orientation of the microcrystallites as well as the role of water diffusion throughout the enamel structure has been discussed.