Niobium can improve corrosion resistance and biocompatibility of implants. As early as 1991, some scholars conducted relevant research and analysis on pure titanium implants and pure niobium implants implanted in rabbit bone, and the results showed that the opening torque of pure niobium implants was significantly higher than that of pure titanium implants, and it was speculated that this might be caused by the more irregular surface morphology of pure niobium implants compared with pure titanium implants. However, more studies are still inclined to improve the biocompatibility of titanium alloys by introducing niobium into titanium alloys, reducing the precipitation of toxic metals (such as nickel and vanadium) ions in titanium alloys, and reducing the elastic modulus of titanium alloys and improving the mechanical strength of implants. Sakai et al. examined the effects of 15 commonly used biomaterial elements on the bioactivity of osteoblast-like cells, and showed that vanadium and nickel were much more cytotoxic than niobium, both in particulate and ionic form. In 2020 developed a titanium-niobium alloy with the closest physical properties to bone tissue, helping to create high-quality implants to effectively repair damaged bones. After finding soft niobium titanium alloys with a niobium content ranging from 5% to 50%, the researchers found that titanium alloys with a niobium content of 25% had the highest cell activity. Center manager said that as the niobium content increases, the formation of oxide nanotubes on the surface of titanium alloys accelerates. Nanotubes grown by electrochemical anodizing, due to their hollow structure, can be loaded onto the surface of the implant before surgery to complete local drug delivery, such as antibiotics or growth factors. By changing the parameters of niobium content and electrochemical anodizing, the geometric parameters, physical and mechanical properties of nanotubes can be controlled to create implants with specific characteristics that maximize the requirements of clinical targets.
In surgical defect repair, repair materials and stent materials need good ductility, specific strength, wear resistance, corrosion resistance and so on. Due to long-term implantation in the human body, biological indicators such as biocompatibility and cytotoxicity of metal materials have also received extensive attention from researchers. Reducing the elastic modulus of metal materials as close as possible to bone tissue in order to reduce the stress shielding effect is one of the recent efforts of researchers. According to relevant studies, adding non-toxic metal element niobium to titanium alloys can effectively reduce the elastic modulus of the alloy and improve corrosion resistance.
