Experts said that cranial defect is a very common disorder in neurosurgery clinic, which often can be caused by traumatic injuries such as traffic accidents, production safety accidents, falling from height, etc., or left behind by intracranial tumors, cerebral hemorrhage and other cranial brain diseases itself and craniotomy. The harm of cranial defects lies in the destruction of the integrity of the skull, the closure of the cranial cavity and the stability of the intracranial environment, thus causing cerebrospinal fluid circulation, blood circulation disorders, affecting the normal operation of the nerve function, resulting in a series of neurological symptoms. Some patients may manifest as dizziness, headache, limb weakness, poor fine activities, weakened vision, emotional instability, irritability and so on. Is craniosynostosis a fear of heat? As for whether cranial defects are afraid of heat, we have not encountered any patients reflecting this kind of situation in clinical work, and there are no relevant reports in the literature. However, there is a common fear of heat in patients who have used titanium mesh material for cranial bone repair after cranial bone defects. Because titanium mesh is a metal material with strong thermal conductivity, if the external environment is hot, it is easy to conduct through the titanium mesh to the skull, and if under strong sunlight, there may even be burning, burning sensation. In addition, it is because of the heat conduction effect of titanium mesh material, titanium mesh repair of the skull after the patient will also be more afraid of cold. In addition, titanium mesh skull repair has some other defects and shortcomings, such as postoperative infection, rejection, wear and tear of the scalp, titanium mesh exposed, easy to deformation and collapse, affecting the CT, MRI examination and so on. Therefore, the use of titanium mesh material for cranial bone repair is not very recommended at present. The repair of cranial defects, one is to choose the excellent performance of the repair material, and secondly, the surgical operation skills also have high requirements. At present, there is a new type of special polymer material – polyether ether ketone PEEK material, the performance is very excellent, PEEK material does not conduct heat, the patient will not be afraid of heat and cold, in addition to the hardness, stiffness, strength, elasticity, tissue compatibility of PEEK material and autologous skull are comparable to that of the material, which can be very good to overcome the various problems that may arise from the titanium mesh material. PEEK material can overcome the above problems of titanium mesh and become the new trend of cranial bone repair material. It can achieve the organic unity of anatomical integrity, perfect function and beautiful appearance, which has been recognized and praised by patients, and is the preferred repair material for patients with cranial bone defects.