The skull is irreplaceable in its mission to protect the safety of the brain. If craniotomy is required due to traumatic brain injury or disease, this often leads to cranial defects. Many people do not realize the seriousness of cranial defects in life, and always feel that there is no need to repair the cranium, is this really true? There are many hidden dangers of not repairing the skull for a long time after cranioplasty, and patients should pay attention to the impact of not repairing the skull from three aspects: 1. Cranial defects are directly affected by the aesthetic appearance, if the defect area is large and the head is sunken, it looks very scary. If not repaired for a long time, the patient’s psychology will also suffer a blow, and even become inferior and depressed. 2.Safety aspect. After the skull defect, the brain tissue is only covered by the scalp, lacking the protection of the hard shell, so it is easy to bump if not repaired in time, which will directly injure the brain tissue and have more serious consequences. 3, physical aspects. Cranial defect can lead to a series of cranial defect syndrome, such as headache, dizziness, numbness and weakness of limbs, emotional instability, irritability, etc., which seriously affects the quality of life. From all these, it is clear that cranial defects should be repaired before it is too late. Our team is currently performing extensive skull repair surgery using PEEK, a very safe and advanced polymer material. PEEK is a safer, more advanced polymer than any other material used in the past. It is histocompatible, hard, flexible, and stable, comparable to autologous cranial bone, so there is no need to worry about problems after surgery. In addition, we continue to optimize the design of the material and upgrade the technology, and we have also successfully incorporated the concept of aesthetic plastic surgery to perform comprehensive PEEK cranioplasty, with an aesthetically pleasing recovery.