Many people suffer from some kind of brain disease or a major traffic accident that results in severe cranial trauma, and these times require craniotomy. When it comes to craniotomy, people are very worried because after all, it is an operation on the head. Therefore, in order to better ensure the safety and effect of craniotomy, it is important for patients to choose a regular hospital and let experienced and technically mature experts to perform the surgery. Do I have to do skull repair after craniotomy? This is a question that many patients often consult, because no matter the disease factor or accident factor to perform craniotomy, it is necessary to open the window in the patient’s skull before it can be completed, there are some cases where the bone flap cannot be returned immediately during the operation, and the skull defect may be left behind. Once the skull is defective, the intracranial tissues lack external protection and may be at risk at any time. If a cranial defect is left after a craniotomy, the importance of cranial repair should not be overlooked. If a large skull defect is left after craniotomy with debridement and decompression, or if the defect is more than 3cm in diameter, or if it seriously affects the aesthetics, or if it causes some physical or psychological discomfort to the patient, then cranial repair surgery is recommended in time. A more suitable time for repair is 2 to 3 months after craniotomy for better recovery. Currently, our team is performing a wide range of cranial repair procedures, using a safe polymer material, polyether ether ketone (PEEK), for patients with good clinical results. The PEEK material has excellent properties, is very close to the autologous cranial bone, is highly protective, aesthetically pleasing, and has ideal repair results. In addition, our team is constantly researching and improving the technology, optimizing the design of the material, and also successfully integrating the concept of cosmetic surgery into the procedure to perform comprehensive PEEK cranioplasty, resulting in a more natural-looking postoperative recovery.