Causes of cranial defects: Cranial defects are partly caused by open craniocerebral injuries or firearm penetrating injuries, and some patients have residual defects due to debridement flap decompression or resection of diseased cranium. In recent years, the proportion of cranial defects has increased due to the good results of debridement for severe traumatic brain injury patients. Harms of cranial defects: After cranial defects, firstly, patients will be criticized by the outside world due to the aesthetic problem, which will cause low self-esteem and depression. Secondly, patients may suffer from dizziness and headache, memory loss, and fear of loud noises. In addition, it may also cause complications such as brain bulging, brain atrophy, hydrocephalus, etc., which will pose a major threat to the patient’s life and health. Therefore, timely cranial repair surgery can not only make patients recover health as soon as possible, but also reduce the psychological pressure of patients to a certain extent. Recovery time after cranial bone repair: Cranial bone repair is a relatively simple neurosurgery, recovery faster surgery, from the current technology, the operation process basically does not have the risk, but also can basically achieve the requirements of covering the defective area, but the effect of postoperative repair and recovery time is due to the implantation of different materials and repair methods vary from one to another. At present, the polyetheretherketone peek cranioplasty is carried out, with the new peek as the implant material, the embedded repair method, and the formulation of a personalized plan (repair + plastic surgery), and the patient’s overall shape is good after the operation. The surgery itself is a very rapid recovery, the next day after the operation, you can get out of bed, five to seven days can be discharged from the hospital, plus preoperative examination of two to three days, the entire recovery time is basically about half a month.