Construction and properties of poly( lactic-co-glycolic acid )/calcium phosphate cement composite pellets with microspheres-in-pellet structure for bone repair

Abstract Granular-type grafts can be easily filled in complex bone defect sites, and the interconnected voids formed by stacking of granules can provide spaces and channels for the ingrowth of new bone tissues and blood vessels. In this study, poly( lactic-co-glycolic acid )/calcium phosphate cement composite (PLGA/CPC) pellets with sea island structure were fabricated by the freeze-dripping method. The phase composition, compressive stress, morphology, in vitro degradation and cytology behavior of PLGA/CPC pellets were investigated. The results indicated that the earlier compressive stress of CPC pellets was reinforced by the addition of PLGA microspheres and the in situ pores were generated inside pellets along with degradation of PLGA microspheres. Besides, the proliferation and alkaline phosphatase (ALP) activity of mouse bone mesenchymal stem cells (mBMSCs) cultured on PLGA/CPC pellets was comparable than CPC pellets. The PLGA/CPC pellets are promising to be used in bone defect repair.