3-Dimensional functionalized polycaprolactone-hyaluronic acid hydrogel constructs for bone tissue engineering

AimAlveolar bone regeneration remains a significant clinical challenge in periodontology and dental implantology. This study assessed the mineralized tissue forming potential of 3-D printed medical grade polycaprolactone (mPCL) constructs containing osteoblasts (OB) encapsulated in a hyaluronic acid (HA)-hydrogel incorporating bone morphogenetic protein-7 (BMP-7). Materials and MethodsHA-hydrogels containing human OBBMP-7 were prepared. Cell viability, osteogenic gene expression, mineralized tissue formation and BMP-7 release invitro, were assessed by fluorescence staining, RT-PCR, histological/-CT examination and ELISA respectively. In an athymic rat model, subcutaneous ectopic mineralized tissue formation in mPCL-hydrogel constructs was assessed by -CT and histology. ResultsOsteoblast encapsulation in HA-hydrogels did not detrimentally effect cell viability, and 3-D culture in osteogenic media showed mineralized collagenous matrix formation after 6weeks. BMP-7 release from the hydrogel was biphasic, sustained and increased osteogenic gene expression invitro. After 4weeks invivo, mPCL-hydrogel constructs containing BMP-7 formed significantly more volume (mm(3)) of vascularized bone-like tissue. ConclusionsFunctionalized mPCL-HA hydrogel constructs provide a favourable environment for bone tissue engineering. Although encapsulated cells contributed to mineralized tissue formation within the hydrogel invitro and invivo, their addition did not result in an improved outcome compared to BMP-7 alone.