Calcium phosphate cement(CPC)is broadly used as bone substitute in dentistryand orthopedic for its high biocompatibility as well as osteoconductivity.However,CPC demonstrates a high degree of crystallization and resultant high stability in structure after hardening,which usually results in a low rate of degradation after implantation in bone tissue and leads to permanent existence of the cured cement in the defect of the bone as a foreign body forever.Strontium has been added to increase the rate of degradation.