Biocompatibility of ferric calcium phosphorous oxide ceramics

The objective of this investigation was to ascertain the biocompatability of a ferric calcium phosphorous oxide ceramic (FECAP). The FECAP ceramic was fabricated from stock powders combined in a ratio of 46:40:14 by weight of Fe2O3:CaO:P2O5. The composite oxides were mixed for homogeneity, pressed into a 20g block, and calcined in a crucible at 1100 degrees C for 12 hours. The calcined ceramic was then ground in a ball mill before separation into particle sizes of 38-45 microns and 63-75 microns, by an automatic siever and shaker. Calcined powders of each particle size were mixed with polyvinyl alcohol binder (0.025g PVA/1.0g of FECAP), and pressed into 0.5g pellets in a 5/16" (internal diameter) die at a 1820 kilogram load using a Carver hydraulic press. FECAP pellets were then sintered at 1100 degrees C for 12 hours. For this investigation, sixty albino (Sprague-Dawley) rats weighing 125-425 g each, were distributed into four groups: non-operated controls, sham-operated controls, and two groups subcutaneously implanted with ceramics 38-45 microns and 63-75 microns FECAP ceramics, respectively. Three rats from each group were sacrificed at three, five, seven, and twenty-one days post-surgery. Morphologic examination of the implant and implant site as well as hematocrit data indicate that this ferric-calcium-phosphorous oxide ceramic is biocompatible. Data obtained todate suggest that sintered FECAP should have a wide variety of dental and medical applications, especially where iron deficiency is a concern.