In the current life situation, the number of patients with cranial defects is gradually increasing, however, the defects bring serious harm to the body. What causes cranial defects? Scalp and skull defects can be divided into two categories: congenital and traumatic. Congenital scalp and cranial defects are rare, and the main clinical causes are acquired scalp and cranial defects caused by various traumas. Traumatic scalp defects are often caused by scalp avulsion, deep burns, electric shock, traffic accidents, etc. They can also be seen after severe infections, osteomyelitis or tumor resection. According to the depth of their injury, they can be divided into two categories: partial scalp defects (presence of cranial periosteum) and full scalp defects (cranial periosteal defects). Among the treatment of craniocerebral trauma and some brain diseases, debridement decompression is the preferred means among the second-line methods for treating malignant high cranial pressure, and debridement decompression can effectively reduce the intracranial pressure and the compression of the brainstem vital center. This will inevitably result in more and more cases of cranial defects. Cranial defects can cause changes in brain pressure, which can increase the risk of hydrocephalus and atrophy and affect the recovery of brain function, which can be life-threatening in severe cases. Therefore, timely repair of cranial defects is essential. PEEK is the material of choice for patients.