ABSTRACT
High nitrogen nickel-free stainless steel (HNNFSS) has excellent mechanical properties, corrosion resistance and biocompatibility, but its strength advantage is not fully used even though with one time higher than that of the conventional 316â¯L stainless steel. In this work, the lightweight design of HNNFSS bone plate was studied using finite element analysis, and the effect of lightweight plate fixation on histological and biomechanical behavior of healing bone were also researched on fractured rabbit femur. The finite element analysis results showed that the lightweight plate within 18.2% thickness reduction had higher bending strength and more homogeneous stress distribution compared with 316â¯L stainless steel plate. There was no obvious difference in radiography, histology analysis of callus and expression pattern of insulin like growth factor-1(IGF-1) of callus between the lightweight HNNFSS plate group and 316â¯L stainless steel plate group in animal test, and the IGF-1 concentrations of callus and the biomechanical bending test results also showed no statistical significance (pâ¯>â¯0.05), even though the data of the lightweight HNNFSS plate group were relatively better than that of 316â¯L stainless steel plate group. Therefore, the high nitrogen nickel-free stainless steel has the lightweight potential to keep good fixing function and improve bone healing compared with 316â¯L stainless steel plate.
Subject(s)
Bone Plates , Materials Testing , Nickel/chemistry , Stainless Steel/chemistry , Animals , Biomechanical Phenomena , Bony Callus/diagnostic imaging , Bony Callus/pathology , Femoral Fractures/diagnostic imaging , Femoral Fractures/pathology , Femoral Fractures/surgery , Finite Element Analysis , Fracture Healing , Insulin-Like Growth Factor I/metabolism , RabbitsABSTRACT
The high nitrogen nickel-free stainless steel has offered an alternative to further improve the performance of the coronary stents, and simultaneously avoids the potential harms of nickel element. Both cold deformation and pitting corrosion are very important for coronary stents made of stainless steel. In this work, the effect of cold deformation on the pitting corrosion resistance of a high nitrogen nickel-free stainless steel (00Cr18Mn15Mo2N0.86) in 0.9% saline solution was investigated. The results showed that the pitting corrosion of the steel was nearly unchanged with increases of the cold deformation up to 50%, indicating that the higher nitrogen content can reduce the negative effect of cold deformation on the pitting corrosion resistance, which is beneficial for the long term service of coronary stents in blood vessel.
