Implanted bovine apatite is highly osteoconductive, since it serves th
e host tissue as a ''guide-line'' for the deposition of newly developi
ng bone tissue. It is well tolerated, but it showed no signs of being
resorbed during the course of the experiment. Previous impregnation of
the bovine hydroxyapatite with a low molecular humate substance obvio
usly encourages its resorption. This is most easily explained by the k
nown ability of humate to induce the activation of leucocytes. The occ
asional over-resorption of the apatite is dependent (1) upon the prepa
ration of the implant (granulate) and (2) the local concentration of t
he humate. Future research is being directed towards the production of
a satisfactorily usable form of humate and apatite and the investigat
ion of its HIV blocking action on heterologous cancellous bone.