INCORPORATION OF TETRAVALENT CATIONS IN THE CALCIUM FLUOROAPATITE LATTICE

In order to determine the effect of tetravalent cations on the inorganic phase of hard tissues, a model study has been undertaken, investigating a series of fluoroapatites in which part of the Ca(II) ions were substituted by Th(IV), Zr(IV) or Hf(IV). Diffractometric and vibrational spectroscopic studies show that low concentrations of the incorporated metals neither affect the crystallographic characteristics nor the strength of the P-O bonds of these apatitic materials.