Nowadays, there are three kinds of materials that are commonly used in the world, all of which are polymer chemical synthetic materials: polypropylene, polyester and PTFE. These synthetic materials that need to be implanted in the body are strictly tested by the drug and food supervision department before they are allowed to be used, which is also common in the international arena. These materials have met the criteria for implantation into the human body and meet national and international requirements. The implanted materials do not have rejection reactions, do not cause tumors, and do not cause damage to local tissues.