one hundred and five Wistar rats were randomized into 3 groups and heterogenous decalcified bone matrix (HDBM) + CaCl_2+Na_2HPO_4+KH_2PO_4, HDBM + CaSO_4+Na_2HPO_4+KH_2PO_4, and HDBM + NaCl were implanted into the quadriceps muscle of both thighs of the animals respectively. They were monitored with ~3H-TdR and ~(45)Ca tracing to evaluate the efficacy of the 3 delivery systems to enhance osteogenesis. It was found that coadministration of CaSo_4, Na_2HPO_4, and KH_2PO_4 could significantly enhance the osteogenesis induced by HDBM. It is concluded that HDBM and the coadministration of Na_2HPO_4, KH_2-PO_4, and CaS0-4/CaCl_2 together will be much more effective to induce osteogenesis than HDBM is used singly.