Biological tissues and organs are complex fine structures formed in the long-term evolution of the body. As artificial implants to replace the functions of tissues and organs, there is no doubt that they are very different from biological tissues and organs in structure. In this paper, the similarities and differences of basic structure and performance between biological hard tissue bones and teeth and corresponding artificial coated implants are compared. The results show that biological hard tissue is similar to coated implant in structure, and coated implant can complete the basic functions of hard tissue. A coated composite is a material.