Cranial defects are an increasingly common problem nowadays, such as the occurrence of cranial trauma or craniosynostosis requiring craniotomy. The severity of cranial defects cannot be underestimated, because the skull is a protective barrier for the brain, and it is because of its external protection that the intracranial tissues can function normally, but once cranial defects occur, all this will be broken and will bring more harm to the patient’s body. Firstly, cranial defect will seriously affect the image of appearance, patients will become very low self-esteem and reluctant to communicate with others; secondly, the intracranial pressure and intracranial environment will be changed after cranial defect, the brain blood circulation and cerebrospinal fluid circulation will be affected, which will cause a series of neurological dysfunction, patients will often feel dizzy, headache, etc., and memory will gradually decline; thirdly, cranial Thirdly, the brain lacks protection after the defect, and if there is a secondary injury, the consequences will be more serious. Cranial defect must be paid attention to, timely go to the hospital to do cranial repair surgery to save health, but in the cranial repair problem, the choice of repair material is a major key, if the material is not suitable surgery is difficult to succeed. For example, titanium mesh material is widely used in many hospitals nowadays, although it is more advanced than the past material, there are many shortcomings, some patients will have infections and rejection reactions after surgery, affect the post-operative CT MRI, and even have the possibility of material exposure. The more ideal material for skull repair surgery is the polyetheretherketone PEEK material, which is a very advanced polymer material with good histocompatibility and no postoperative rejection. The peek skull repair, the chance of leakage is not high? Many patients also have such concerns, but in fact, do not be afraid, PEEK material properties and the autologous cranial bone is very close to, after surgery generally will not occur material exposure. Of course, this is also related to the operator’s technical level, close management during the perioperative period, and the patient’s own protective attention after discharge.