In medical transplant operations, artificial joints and artificial bone substitute materials should have the following basic characteristics: light weight, high strength, biocompatibility, corrosion resistance, and tissue reactions that occur in the body of the implant will not cause Material degradation, fatigue and damage caused by repeated stress are few. The more important properties of metal implants are formability, machinability and polishability. They must maintain function during the expected lifetime and will not deteriorate when subjected to fatigue, wear, corrosion and impact loads... Titanium and titanium alloy materials Appears to satisfy all the above requirements. Dental tray powder, polypropylene, plexiglass and other artificial joint materials used earlier have low strength, easy to fold, and poor biocompatibility. Later, they were changed to stainless steel. However, stainless steel not only corrodes and breaks in the body's receptor fluid, but also has a large specific gravity, which is about twice that of human bones. Co-Cr alloy is also an excellent artificial joint material, but unfortunately, cobalt and chromium are toxic to the human body. Titanium and titanium alloys have a small specific gravity (similar to that of human bones), high strength, good mechanical processing, and excellent corrosion resistance. They naturally become a new and ideal artificial joint material.
The titanium materials prescribed for surgical implant materials are mainly pure titanium and Ti-6Al-4VELI alloy. In recent years, the graft materials Ti-13Nb1-13Zr and Ti-6Al-7Nb, which have good affinity with the human body, have also been approved by ASTM standards. Artificial bones and bone joints made of titanium can be regenerated on the cells without affecting bone growth, and have good affinity with human bones, epithelium and tissues.
At present, titanium and titanium alloys have been widely used in artificial bones, artificial bone joints, joint foot plates, broken bone fixators, intramedullary nails, artificial heart valves, skull bones, etc. According to incomplete statistics, China's annual demand for titanium alloy artificial joints exceeds 5,000 sets, and clinical applications have received good results.
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