Introduction And Performance Comparison Of Surgical Implants

1. Titanium, as an emerging material, has been used for decades in the pharmaceutical industry, surgical instruments, human implants, and other fields in China and the world, and has achieved great success.

2. Titanium and titanium alloy can be used to manufacture artificial joints, bone plates, and screws for bone and joint injuries caused by trauma and tumor in the human body. It is also used for hip joint (including femoral head), knee joint, elbow joint, metacarpophalangeal joint, interphalangeal joints, mandible, artificial vertebral body (spinal orthosis), pacemaker shell, artificial heart (heart valve), artificial dental implant, and titanium mesh in skull shaping and other aspects.

3. Requirements for implant materials can be classified into three aspects: The bio-compatibility of materials with the human body, the corrosion resistance of materials in the human environment, and the mechanical properties of materials. As long-term implant materials, there are seven specific requirements as follows:

① Corrosion resistance ;

② Bio-compatibility.

③ Excellent mechanical properties and fatigue properties;

④ Toughness.

⑤ Low modulus of elasticity.

⑥ Good wear resistance in the assemblage.

⑦ Satisfactory price;

4. The main materials for surgical implants are: metals, polymers, ceramics, etc. Metal materials also include stainless steel, cobalt-based alloys, and titanium-based alloys.

A comparison of material properties with bone properties and implant materials is shown in Table 1 and Table 2. As can be seen from Table 2, stainless steel is cheap and easy to process, but corrosion resistance and biocompatibility are not as good as titanium alloy; The wear resistance of cobalt-chromium alloy is better than titanium alloy, but the density is larger and too heavy; titanium and titanium alloys are being increasingly valued due to their high specific strength, good biocompatibility and good corrosion resistance to body fluids. The deficiencies of titanium alloy are poor wear resistance, difficulty to cast, and poor processing properties.

Table1 Comparison of material properties and bone properties

Table 2 Characteristic comparison of the three implant materials

Note： A－excellent， B－good， C－middle， D－bad