Original Title: Development and Application of Medical Titanium and Titanium Alloys for Surgical Implants 1. Introduction Titanium and its alloys used as surgical implants have many advantages, such as low density, high strength, good toughness, good biocompatibility, non-toxic, low elastic modulus, good corrosion resistance, low X-ray absorption rate and so on, so they play an increasingly important role in medical metal materials. Titanium and its alloys can be used for the repair and replacement of human hard tissues, or for the repair of cardiovascular and soft tissues and the manufacture of artificial organs. They are special functional materials closely related to human life and health. At present, it has become the preferred metal material for replacement or repair of artificial joints, artificial bones, broken bone bindings, spinal correction rods, intramedullary nails, artificial heart valves, dental implants, skull and other products. The world's population is nearly 6.5 billion, and the global aging problem is very serious. According to the data of F S Company, the compound growth rate of the global orthopaedic implant device market in the past five years is about 10.4%, which is expected to reach 27.7 billion US dollars by 2015, while the Chinese orthopaedic implant device market will grow to 16.6 billion US dollars, with a compound annual growth rate of 18.1%. It can be seen that titanium and its alloys are the preferred materials for medical metal materials, and their future market demand is very strong. Therefore, it is of great significance to increase the research and development and application promotion of medical titanium and its alloys in China. 2. Research and development status of titanium materials for surgical implants 2.1 Vanadium-free medical titanium alloy Ti-6Al-7Nb alloy is a medical alloy developed by Sulzer Medical Technology Company in Switzerland. Compared with Ti-6Al-4V alloy, the properties of Ti-6Al-7Nb alloy are equal to that of Ti-6Al-4V alloy, which is a safe and potential material for human implantation. Many kinds of Ti-6Al-7Nb alloy implants have been put into clinical application with good results. Another medical titanium alloy, Ti-5Al-2.5Fe, was developed by Germany. Compared with Ti-6Al-4V alloy, vanadium is replaced by cheap and non-toxic iron element. Ti-5Al-2. 5Fe is a medium-strength material, which is equivalent to Ti-6Al-4V in terms of mechanical property,nickel titanium wire, toughness and fatigue strength. These two alloys have also been developed in China. Ti-6Al-7Nb and Ti-5Al-2.5Fe alloys have been developed by the joint efforts of Baotai Group Co., Ltd., Beijing Central Research Institute for Nonferrous Metals, Hebei Medical University, Shandong Wendeng Orthopedic Hospital and the Second Orthopedic Medical Equipment Factory of Tianjin Medical Instrument Industry Corporation. The results of biological experiments show that the alloys have good biocompatibility. And can form the good osseointegration with the bone organization, at present domestic by Shanghai Ai Liai metal material limited company and so on unit proxy distribution. 2.2 New Beta Titanium Alloys Since the 1990s, there have been reports about the potential hazards of V and Al elements to human body in titanium alloy implant materials. Therefore, the development of advanced biomedical metal materials with excellent comprehensive mechanical properties and more compatible with human soft and hard tissues and biomechanics, the new β-titanium alloy, has become the focus of biomedical metal materials research. A series of new type β titanium alloys were developed by adding non-toxic elements such as Nb, Ta, Zr,Titanium 6Al4V wire, Mo and Sn. 2.3 Ti-Ni alloy. Ti-Ni shape memory alloy is a new type of functional material. This kind of functional material has peculiar shape memory effect, superelasticity, fatigue resistance, wear resistance, corrosion resistance and good biocompatibility. Therefore, the alloy is widely used in the medical field. The successful application of Ti-Ni shape memory alloy in orthopaedic clinic has attracted the attention of orthopaedic experts and clinicians, and it is called "magic metal". The deformation temperature of NTSMA used in orthopedic clinic is 0-5 ℃, and the recovery temperature is 37 ℃. Aft that fracture is fixed by the NTSMA material, the shape is restore by heating under body temperature or hot saline wet compress, but the bone restricts the material from restore, so that a dynamic and continuous pressure or clamping force is generated at the broken end of the fracture to achieve the effect of fixing the fracture. Expand the full text 2.4 Porous titanium alloy The surface structure of surgical implants is closely related to the biological behavior after implantation. Compared with a compact material, the introduction of the pores remarkably reduces the elastic modulus of the titanium and the titanium alloy, the strength and the modulus of the porous titanium can be adjusted to be comprehensively matched by changing parameters such as porosity, pore diameter and the like, and the open through hole structure of the porous titanium is fully utilized to promote the adhesion and ingrowth of bone cells and regeneration and reconstruction of bone tissues so as to accelerate the healing process, O that the titanium and the titanium alloy can realize the matching of the material and the elastic modulus of the bone under the condition of keeping certain strength. At the same time, the rough surface geometry of porous titanium alloy can promote the growth of new bone tissue into the pores, which not only strengthens the biological fixation between the implant and bone, but also enables the stress to be transmitted to the surrounding bone along the implant.. 2.5 Titanium alloy surface activation technology The surface activation technology of titanium alloy is one of the key fields in the research and development of orthopedic implant materials. The surface of the implant is in direct contact with the human body. Through surface modification, biocompatibility can be improved and wear can be reduced, thereby reducing the possibility of implant loosening and ensuring the long-term performance of the implant.. The composite oxide coating was formed on the surface of titanium alloy by anodic oxidation, hydrothermal treatment and heat treatment. The prepared gradient coating has complete crystal form, titanium bar grade 5 ,titanium tubing price, and the surface of the gradient coating has high capability of inducing a bone hydroxyapatite layer to form and cell adsorption and proliferation capability, and has good biocompatibility. 2.6 Laser Near-Net Shaping of Surgical Implants Laser near-net shaping technology is a 3D printing manufacturing technology, combined with computer control, which gradually uses high-energy beams to melt titanium alloy powder in the molten pool and process it into specific shapes of orthopaedic implants or dental restorations. Northwestern Polytechnical University and other research institutes have done a lot of research on the laser solid forming process of pure titanium and other medical metals. The mechanical properties and fatigue properties of pure titanium implants prepared by this technology are higher than those of pure titanium, which can meet the requirements of dental implants for mechanical properties. At present, some progress has been made in the research of processing titanium-nickel alloy and titanium alloy vascular stents by laser near-net shaping technology in China. 3. Application of materials for surgical implants 3.1 Overview of foreign applications Ti-Ni alloys with unique shape memory properties have been used in stomatology, neurosurgery, cardiovascular surgery, thoracic surgery, otorhinolaryngology, hepatobiliary surgery, urology and gynecology since their successful development. Products include dental orthopedic wire, root canal file, spinal orthopedic rod, bone plate, intramedullary needle, patella claw, guide wire, guide needle, cardiac patch, vascular stent, thrombus filter, esophageal stent, respiratory stent, biliary stent, urethral stent, rectal stent, duodenal stent, external auditory canal stent, IUD, etc. The hip prosthesis system manufactured by STRYKER Group, one of the largest orthopaedic professional group companies in the world, uses Ti-12Mo-6Zr-2Fe alloy, which has reached the highest standard of orthopaedic clinical requirements in terms of quality, function and clinical effect. At the same time, the anterior cervical plate system made of Ti-Mo-Zr-Fe alloy has been used in clinic. At present, these two products have been introduced into the Chinese market. Titanium alloy precision casting prostheses were developed and used in clinic in Germany in the 1980s, which promoted the development of modern functional prostheses. Since then, titanium alloy precision casting prostheses have been widely used in various countries. Craniomaxillofacial plastic surgery is widely carried out abroad, especially in Germany, the United States, Japan and other countries. Plastic surgery brings confidence and happiness to people. Internal fixation devices used in craniomaxillofacial plastic surgery are mainly pure titanium plates of various shapes and specifications and pure titanium screws of various specifications. 3.2 Overview of domestic application Baotai Group, the largest professional titanium and titanium alloy manufacturer in China, has been cooperating with other scientific research institutions in the research and development of titanium bone, titanium stent and other human implant materials since the 1970s, and has achieved good results. Since the 1970s, China has begun to use domestic titanium and titanium alloy artificial bones and joints for clinical treatment. The artificial femur and hip joint produced have good clinical results. In the mid-1980s, the number of domestic titanium and titanium alloy processing materials used to manufacture human implants has been increasing. Femoral head, hip joint, knee joint, elbow joint, shoulder joint and metacarpophalangeal joint made of titanium and titanium alloy have been transplanted into human body and achieved very good results. Significant progress has also been made in the development of new beta titanium alloys for orthopaedic applications and titanium alloys for dental restorations in China. A variety of medical titanium alloys independently developed by Shenyang Metal Research Institute, Beijing Nonferrous Metals Research Institute and Northwest Nonferrous Metals Research Institute have been used in surgical implants and vascular stents. In the application of porous titanium alloy, Tangdu Hospital of the Fourth Military Medical University, Northwest Institute of Nonferrous Metals, Shanghai Jiaotong University and other research institutes have designed and manufactured porous titanium alloy implants, which have been widely used in clinic and achieved good results. 4. Conclusion The defect of human hard tissue caused by the aging of population has become a major problem worldwide. China has a large population, the aging problem is very serious, and there are many patients who need rehabilitation surgery with the help of medical implant materials. According to statistics, in the past 30 years, the market of surgical implants in China has developed at an alarming rate. The average growth rate in the past 10 years has been maintained between 15% and 30%, and is expected to continue to grow at a rate of more than 10% in the next 10 years. It can be seen that the market prospect of titanium alloy implants in China is very broad. Although China has done a lot of research work in the research and application of titanium alloy materials for surgical implants and made remarkable progress, compared with developed countries such as Europe, the United States and Japan, there is a big gap in the design, manufacture, processing, equipm ent, surface treatment and technological level of titanium alloy implants. The implants produced in China are difficult to meet the market demand, and most of the high-end implants need to be imported from abroad,3d titanium wire, which has brought unprecedented opportunities and challenges to medical material research units, material manufacturers, medical research institutions and clinical medical experts in China. These units should strengthen cooperation and work hard to achieve the localization of high-end implants for the benefit of the people. To promote the healthy and stable development of China's medical titanium alloy industry. Return to Sohu to see more Responsible Editor:. yunchtitanium.com