Atomic force microscopy investigations on pits and debris related to fretting-corrosion between 316L SS and PMMA

In the case of hip prostheses, debris generation, due to the fretting-corrosion phenomenon between the femoral stem and the bone cement is one of the most significant causes of reintervention. In this study we use atomic force microscopy (AFM) to analyze PMMA particles and pitting corrosion on 316L SS as a function of chlorides and albumin concentration. Without albumin, the number of pits increases with the chlorides concentration. Contrary to the protective effect of albumin on global corrosive wear, albumin tends to increase the number of pits. The number of ejected particles highly depends on electrochemical conditions and the in vivo conditions, Open Circuit Potential, seem to lead to a small number of particles. This work has also explored atomic force microscopy as a “new” characterization technique for wear debris and demonstrates that 80% of particles have a size inferior to 100 nm, which is the ‘critical size’ for tissues response.