The human body is mysterious and has not been fully deciphered for thousands of years. But cranial repair is not mysterious, ancient people used various primitive materials a thousand years ago to perform cranial repair when medical technology was not developed. With the development of medical science and technology, more and more doctors started to research on cranial repair materials and more and more materials were applied to cranial repair. Through the efforts of generations of medical researchers, good materials have been invented and applied in cranial repair surgery, and good clinical results have been achieved. Currently, the most widely used material for cranial repair is titanium mesh, and the newest material is PEEK, which is relatively inexpensive and has been used for a long time. Prior to the advent of PEEK, titanium mesh was the first choice for cranial repair materials. With its widespread application, adverse side effects have been identified in many patients in clinical practice. The obvious ones are CT artifacts, which often lead to misdiagnosis, and postoperative sensitivity to heat and cold, chronic local pain, high subcutaneous fluid accumulation, and poor aesthetics of the repair site. The clinical application of PEEK goes further than that of titanium mesh. The 3D technology is used to shape the damaged bone window according to the patient’s CT test data before surgery, precisely fitting the defect area with no protrusion or depression at all. Highly fused with autologous bone, it does not interfere with growth and development, and the material’s various properties resemble those of human cranial bone, making it an ideal cranial repair material currently proven by clinical practice. The material advantages of PEEK are evident in the clinical setting and are readily apparent to patients. From current clinical applications, no suspected discomfort has been found with cranial bone repair using PEEK. Of course, nothing can be perfect. All that can be said is that PEEK is by far the ideal cranial bone repair material recognized by the medical community, bar none. I’m afraid that its drawback is that it is not well known by patients and cannot be popularized in hospitals nationwide.