Cheng Alice, Cohen David J, Kahn Adrian, Clohessy Ryan M, Sahingur Kaan, Newton Joseph B, Hyzy Sharon L, Boyan Barbara D, Schwartz Zvi
Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, USA.
Department of Biomedical Engineering, Peking University, Beijing, China.
Ann Biomed Eng. 2017 Aug;45(8):2025-2035. doi: 10.1007/s10439-017-1831-7. Epub 2017 Apr 13.
The objective of this study was to examine the ability of 3D implants with trabecular-bone-inspired porosity and micro-/nano-rough surfaces to enhance vertical bone ingrowth. Porous Ti-6Al-4V constructs were fabricated via laser-sintering and processed to obtain micro-/nano-rough surfaces. Male and female human osteoblasts were seeded on constructs to analyze cell morphology and response. Implants were then placed on rat calvaria for 10 weeks to assess vertical bone ingrowth, mechanical stability and osseointegration. All osteoblasts showed higher levels of osteocalcin, osteoprotegerin, vascular endothelial growth factor and bone morphogenetic protein 2 on porous constructs compared to solid laser-sintered controls. Porous implants placed in vivo resulted in an average of 3.1 ± 0.6 mm vertical bone growth and osseointegration within implant pores and had significantly higher pull-out strength values than solid implants. New bone formation and pull-out strength was not improved with the addition of demineralized bone matrix putty. Scanning electron images and histological results corroborated vertical bone growth. This study indicates that Ti-6Al-4V implants fabricated by additive manufacturing to have porosity based on trabecular bone and post-build processing to have micro-/nano-surface roughness can support vertical bone growth in vivo, and suggests that these implants may be used clinically to increase osseointegration in challenging patient cases.
本研究的目的是考察具有受松质骨启发的孔隙率以及微/纳米粗糙表面的三维植入物促进垂直骨向内生长的能力。通过激光烧结制造多孔Ti-6Al-4V结构，并进行处理以获得微/纳米粗糙表面。将男性和女性人成骨细胞接种在结构上，以分析细胞形态和反应。然后将植入物置于大鼠颅骨上10周，以评估垂直骨向内生长、机械稳定性和骨整合情况。与实心激光烧结对照相比，所有成骨细胞在多孔结构上均显示出更高水平的骨钙素、骨保护素、血管内皮生长因子和骨形态发生蛋白2。体内植入的多孔植入物导致平均3.1±0.6毫米的垂直骨生长以及植入物孔隙内的骨整合，并且其拔出强度值显著高于实心植入物。添加脱矿骨基质糊剂并未改善新骨形成和拔出强度。扫描电子图像和组织学结果证实了垂直骨生长。本研究表明，通过增材制造制备的具有基于松质骨孔隙率且后处理具有微/纳米表面粗糙度的Ti-6Al-4V植入物可在体内支持垂直骨生长，并表明这些植入物可在临床上用于增加具有挑战性的患者病例中的骨整合。
