Research was conducted on 26 adult outbred male and female mice, which were implanted with nickel-titanium wire in the paravertebral zone. The tissues surrounding the implants were studied macroscopically and histologically 2-8 months after the implantation. It was found that the morphological changes of tissues after nickel-titanium wire implantation were detected by microscopical study at the time intervals greater than 2 months after the operation. They included the formation of a thin connective tissue capsule in close vicinity to the implant. No signs of reactive changes in the distant tissues and organs were detected. It is concluded, that the nickel-titanium alloy possesses high degree of biological inertness and may be used for making fixating devices with the memory of mechanical shape that are employed in cranioreconstructive surgery.