In current life, there are many people with cranial defects due to various reasons, such as: traffic accidents, falling objects, traumatic brain injury, traumatic brain decompression with debridement, etc. So what is the differential diagnosis of cranial defects? Next, we will give you a detailed introduction. Cranial bone defect differential diagnosis: 1, cranial bone lesions: bone lesions are seen in almost all patients with Langerhans cell histiocytosis, single bone lesions are more than multiple bone lesions, mainly manifested as osteolytic damage. Cranial lesions are most common, followed by lower limb bones, ribs, pelvis and spine, and jaw lesions are also quite common. Skull fracture: The skull is a sphere-like shell that houses and protects the contents of the cranial cavity. The importance of skull fracture does not lie in the skull fracture itself, but in the concurrent injury of the cranial cavity content. The fractures are classified by shape: linear fractures, depressed fractures, comminuted fractures, and growth fractures in children. Fracture fragments of depressed or comminuted fractures can damage both the meninges and brain as well as cerebral vessels and cranial nerves. Skull fractures account for about 15-20% of craniofacial injuries and can occur in any part of the skull, with the parietal bone being the most frequent, followed by the frontal bone, and then the temporal and occipital bones. Generally, the fracture line does not cross the cranial suture, but if the violence is too great, it can also affect the adjacent bones. The diagnosis can be confirmed by frontal and lateral views of the skull. Due to the different fracture patterns, the treatment and prognosis are also different. 3, huge cranial defect: most of the cranial defects are caused by open cranial injury or firearm penetrating injury, and some patients have residual bone defects due to surgical decompression or diseased craniectomy. In recent years, due to the high brain pressure of heavy craniocerebral injury cases, the prevalence of decompression of the bone flap method, and thus the artificial huge cranial defect is also quite a few, in fact, a considerable number of patients are not required to perform large bone flap decompression, most of them are in the operation of the decision made in the creation of the promotion, not without impropriety. Cranial defect should be timely cranial repair: In recent years we introduced polyetheretherketone peek material cranial repair plastic surgery. To do further plastic surgery on the appearance, the repair and plastic surgery are cleverly connected together, which can effectively avoid the problem of temporal muscle atrophy and asymmetry on both sides after surgery; in addition, polyether ether ketone peek material cranial repair plastic surgery is a new artificial material peek as the implant material, the performance of peek is also very close to the human autologous cranial bone, and there are basically no complications after surgery.