Calcium phosphate cements are of great interest for researchers and their applications in medical practice expanded.Nevertheless,they have a number of drawbacks including the insufficient level of mechanical propertie...Calcium phosphate cements are of great interest for researchers and their applications in medical practice expanded.Nevertheless,they have a number of drawbacks including the insufficient level of mechanical properties and low degradation rate.Struvite(MgNH4PO4)-based cements,which grew in popularity in recent years,despite their neutral pH and acceptable mechanical performance,release undesirable NH4+ions during their resorption.This issue could be avoided by replacement of ammonia ions in the cement liquid with sodium,however,such cements have a pH values of 9–10,leading to cytotoxicity.Thus,the main goal of this investigation is to optimize the composition of cements to achieve the combination of desirable properties:neutral pH,sufficient mechanical properties,and the absence of cytotoxicity,applying Na2HPO4-based cement liquid.For this purpose,cement powders precursors in the CaO-MgO-P2O5 system were synthesized by one-pot process in a wide composition range,and their properties were investigated.The optimal performance was observed for the cements with(Ca+Mg)/P ratio of 1.67,which are characterized by newberyite phase formation during setting reaction,pH values close to 7,sufficient compressive strength up to 22±3 MPa(for 20 mol.%of Mg),dense microstructure and adequate matrix properties of the surface.This set of features make those materials promising candidates for medical applications.展开更多
基金financially support by Russian Foundation for Basic Research(Grant No.18-33-20170).
文摘Calcium phosphate cements are of great interest for researchers and their applications in medical practice expanded.Nevertheless,they have a number of drawbacks including the insufficient level of mechanical properties and low degradation rate.Struvite(MgNH4PO4)-based cements,which grew in popularity in recent years,despite their neutral pH and acceptable mechanical performance,release undesirable NH4+ions during their resorption.This issue could be avoided by replacement of ammonia ions in the cement liquid with sodium,however,such cements have a pH values of 9–10,leading to cytotoxicity.Thus,the main goal of this investigation is to optimize the composition of cements to achieve the combination of desirable properties:neutral pH,sufficient mechanical properties,and the absence of cytotoxicity,applying Na2HPO4-based cement liquid.For this purpose,cement powders precursors in the CaO-MgO-P2O5 system were synthesized by one-pot process in a wide composition range,and their properties were investigated.The optimal performance was observed for the cements with(Ca+Mg)/P ratio of 1.67,which are characterized by newberyite phase formation during setting reaction,pH values close to 7,sufficient compressive strength up to 22±3 MPa(for 20 mol.%of Mg),dense microstructure and adequate matrix properties of the surface.This set of features make those materials promising candidates for medical applications.
