LAUSR

Abstract The bone defects arising as a result of trauma should be filled to provide a framework to support and encourage the growth of new and living bone tissues. Among the many synthetic bone graft substitutes, self-hardening calcium phosphate (CP) cements have been widely used to repair hard tissue defects. In this study, pure dicalcium phosphate (DCP) and lanthanum (La) modified dicalcium phosphate (La-DCP) bone cements were prepared based on acid/base reaction between β- tricalcium phosphate (βTCP) (or La- βTCP) and monocalcium phosphate monohydrate (MCPM) in the presence of water. The prepared bone cements were characterized using XRD, FTIR and SEM techniques to verify both La doping and to explore the alterations in the structural and molecular properties upon doping. With minimum addition of La3+ ions (0.090 mol), the pure phase of brushite transformed into monetite and the plate-like crystals of brushite turned into spheroid particles. The setting times of DCP bone cement declined gradually upon boosting amount of La3+ ions in DCP lattice. As the La amount in DCP cements rose from 0 to 0.225 mol, the compressive strength also increased from 7.90 ± 0.8 to 9.64 ± 1.47 MPa. The dissolution rate of DCP cements improved with addition of La3+ ions. Adsorption/desorption of Fetal bovine serum (FBS) on/from the prepared DCP bone cements showed higher protein loading of La-DCP cements than pure DCP. In vitro experiments on proliferation, adhesion, and osteogenic differentiation of Sarcoma osteogenic (Saos-2) cells indicated that addition 0.225 mol of La3+ ions promoted these properties compared to pure DCP. Results suggested that La3+ (0.225 mol) incorporated DCP bone cement (2La-DCP) has a potential to be used as a bone filler material.