Incorporating simvastatin/poloxamer 407 hydrogel into 3D-printed porous Ti6Al4V scaffolds for the promotion of angiogenesis, osseointegration and bone ingrowth

• Published in: Biofabrication 2016-10, Vol.8 (4), p.045012-045012
• Main Authors: Liu, Hao, Li, Wei, Liu, Can, Tan, Jie, Wang, Hong, Hai, Bao, Cai, Hong, Leng, Hui-Jie, Liu, Zhong-Jun, Song, Chun-Li
• Format: Article
• Language: English
• Subjects: 3D-printed porous titanium scaffolds; bone ingrowth; neovascularization; osseointegration; poloxamer 407 hydrogel; simvastatin
• ISSN: 1758-5090
• DOI: 10.1088/1758-5090/8/4/045012

Three-dimensional porous titanium alloys printed via electron beam melting have low stiffness similar to that of cortical bone and are promising scaffolds for orthopedic applications. However, the bio-inert nature of titanium alloy is poorly compatible with bone ingrowth. We previously observed that simvastatin/poloxamer 407 thermosensitive hydrogel induces endogenous angiogenic/osteogenic growth factors and promotes angiogenesis and osteogenesis, but the mechanical properties of this hydrogel are poor. The purpose of this study was to construct 3D-printed porous titanium scaffolds (pTi scaffolds) filled with simvastatin/hydrogel and evaluate the effects of this composite on osseointegration, bone ingrowth and neovascularization using a tibial defect rabbit model. Four and eight weeks after implantation, the bone volume, bone mineral density, mineral apposition rate, and push-in maximum force of the pTi scaffolds filled with simvastatin/hydrogel were significantly higher than those without simvastatin (p < 0.05). Moreover, filling with simvastatin/hydrogel significantly enhanced vascularization in and around the pTi scaffolds, and a significant correlation was observed between the volume of new bone and neovascularization (p < 0.01). In conclusion, incorporating simvastatin/poloxamer 407 hydrogel into pTi scaffolds significantly improves neovascularization, osseointegration and bone ingrowth.