Effect of plasma immersion ion implantation in TiNi implants on its interaction with animal subcutaneous tissues

Here we investigated in vivo interaction of Si-modified titanium nickelide (TiNi) samples with adjacent tissues in a rat subcutaneous implant model to assess the impact of the modification on the biocompatibility of the implant. Modification was performed by plasma immersion ion processing, which allows doping of different elements into surface layers of complex-shaped articles. The aim of modification was to reduce the level of toxic Ni ions on the implant surface for increasing biocompatibility. We identified a thin connective tissue capsule, endothelial cells, and capillary-like structures around the Si-modified implants both 30 and 90 days postimplantation. No signs of inflammation were found. In conclusion, modification of TiNi samples with Si ions increases biocompatibility of the implant.