The skull is one of the hardest bone tissues in the human body. It is composed of 23 bones of different shapes and sizes, which are articulated and occluded to form a complete and closed cranial cavity that plays an important role in protecting and supporting the brain and craniofacial organs. Cranial defects are a very common disorder that can be caused by trauma or left over from craniotomy due to craniosynostosis. Cranial defects can be very dangerous to human health and should be repaired promptly. Many general local hospitals perform cranial repair surgery, mostly using titanium mesh as the cranial repair material, but in fact this material is not very ideal, and various post-operative problems may often occur. What are the symptoms of titanium skull repair will rejection reaction? Titanium alloy mesh is a relatively mature cranial repair material, which has been used clinically for 20 to 30 years and has certain advancement compared with other materials in the past, but unfortunately, it still has some defects and shortcomings. For example, the titanium alloy rejection problem asked by the above patient, in fact, the histocompatibility of titanium mesh is quite good, generally there will be no rejection reaction, but each person’s physique is different, the sensitivity of the immune system is different, so there will still be a small number of patients in the clinical application of titanium alloy skull repair after the rejection reaction, the main symptom is that the surrounding scalp tissue does not adapt to the titanium mesh, skin ablation The main symptom is that the surrounding scalp tissues do not adapt to the titanium mesh, resulting in skin ablation, or even the exposure of titanium material. In addition, there is another problem that may be mistaken as rejection reaction after titanium alloy cranial repair, which is the abrasion injury of titanium alloy material to the scalp, and in serious cases, it even causes scalp rupture and material exposure, which is similar to rejection reaction. In addition to the rejection reaction, there are other problems with titanium skull repair, such as unsatisfactory shaping effect, sensitivity and discomfort to external hot and cold environment, affecting CT magnetic resonance examination, easy to collapse and deformation by external force, etc. Therefore, it is not recommended to use titanium alloy material for skull repair at present. In fact, there is a new type of polyether ether ketone PEEK material, which is a special polymer material with excellent performance. It is very close to autologous cranial bone in terms of stiffness, rigidity, strength, elasticity, heat insulation, stability, histocompatibility, plasticity, and radiolucency, and can effectively avoid the above problems that may arise from titanium alloy material. It is comfortable and protective after being placed in human body. This PEEK material is widely used in clinical practice, and we continue to improve the technology and optimize the design of the material, and also innovatively introduce the concept of aesthetic plastic surgery, so as to carry out comprehensive PEEK cranioplasty, which can achieve anatomical integrity, functional perfection, and aesthetic appearance of the overall unity, the effect is ideal and well received.