Cytocompatibility of High Nitrogen Nickel-Free Stainless Steel for Orthopedic Implants

Tianchi Ma 1,4),Peng Wan 2),Yuyan Cui 3),Guirong Zhang 4),Jiqiang Li 4),Jihui Liu 4),Yibin Ren 2),Ke Yang 2) and Li Lu 1) 1) School of Stomatology,China Medical University,Shenyang 110002,China 2) Institute of Metal Research,Chinese Academy of Sciences,Shenyang 110016,China 3) Shenyang the Fourth Hospital of People,Shenyang 110032,China 4) Shenyang Stomatoiogy Hospital,Shenyang 110002,China

摘 要：Cytocompatibility of high nitrogen nickel-free stainless steel（HNS） with different nitrogen content was evaluated and compared with a conventional austenitic stainless steel 317L.The MTT assay（3-（4,5-dimethylthiazol-2-yl）-2,5-diphenyltetrazolium bromide） was performed on MG63 osteoblasts to assess the cytotoxicity.The expression of selected marker typical of differentiated osteoblasts,such as alkaline phosphatase activity（AKP）,was also monitored in MG63 cells cultured on the tested materials.As a result,HNS had higher cell growth than 317L;meanwhile the cytocompatibility was increased with increasing nitrogen content.Furthermore,HNS enhanced osteoblasts differentiation,as confirmed by AKP activity.Overall these facts indicated that HNS had higher cytocompatibility than 317L and the nitrogen content contributed to the higher cytocompatibility of HNS.The influence of nitrogen on surface energy further explained the cytocompatibility of HNS.

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