No abstract

SummaryGlass ceramic implants containing 45y0 SiOz with a Ca/P ration of 5 become firmly fixed to bone when placed in a cortical defect of an intact rat femur. The addition of fluoride ions to the implant prevents this fixation. The most significant difference between the two compositions is in their solubilites. The presence of high local concentractions of Ca and PO, ions a t the interface of the soluble non-fluoride containing implant, could account for the deposition of bone a t its surface.It is not felt from these studies, however, that this model will be usable as a mass screening tecunique for evaluating materials variables. less laborous in, vitro systems need to be devised.