Research On The Preparation And Performance Of α-CSH-PMMA Composite Bone Cements

Objective: Poly methyl methacrylate(PMMA)bone cements have been widely used as injectable material for bone injury repair due to the decent injectability and mechanical strength.However,there are also some disadvantages,including bioinertness,non-degradability,and heat generation during curing,of PMMA bone cements which limit their applications.On the contrary,α-Calcium sulfate hemihydrate(α-CSH)has good biocompatibility,degradability and osteogenic property,but degrades fast and has weak mechanical strength.Therefore,this study aimed to develop novel α-CSH-PMMAcomposite bone cements,which possess considerable mechanical strength,biocompatibility,and partial degradability,by supplementing various amount of α-CSH into PMMA matrix.Methods: First,we added 10%,20%,30% and 40%α-CSH into PMMA powder to prepare the α-CSH-PMMA composite bone cements.Then we examined the setting time and mechanical strength of each groups.Meanwhile,wen observed the surface and fractured surface morphology of these cements by SEM observation.At last,we tested the cell biocompatibility through MC3T3-E1 cell culture and CCK8 kit detection analysis.Results: By SEM observation,we can find PMMA microspheres uniformly distributed in bone cement powder.With the addition of α-CSH,the setting time decreased significantly comparing to the PMMA cement.Mechanical properties of bone cement has been tested,the mechanical strength of 10%,15%,20%,30%,40% α-CSH group were 70±2,64±1.5,60±2,57±2 MPa,significantly lower than the PMMA bone cement.Cell proliferation cultured in the extract of each composite bone cements for 24 h were determined using CCK8 assay and cell morphology was observed by microscope.The results showed that the cell growth were pretty well in each treated groups and the cell proliferation was increased as the α-CSH content increasing,but there were no notable difference between these composite bone cement groups.Meanwhile,the cell viability of each α-CSH-PMMA composite bone cement group was significantly higher than the pure PMMA cement group,especially the 40% α-CSH group,and the cell viability was also increased as the α-CSH content increasing.Conclusion: In this study,we incorporated 40% α-CSH into PMMA bone cement to prepare excellent mechanical strength and biocompatibility composite cements with short setting time.