Abstract:  Objective     To explore the construction of an ideal skull defect animal model in rats, and to improve the success rate of skull defect animal model. Methods    Forty adult male SD rats were randomly divided into the control group and experimental group. In the control group, the traditional surgery method of skull defect model was used, only using a hollow drill and the force was perpendicular to the skull surface to drill the full-thickness defect of the skull. The modified surgical method was used in the experimental group rats, by using both hollow and solid drills, and changing the direction of the drill's force at different stages in the skull drilling process. The drilling time, existence of intraoperative complications such as periosteum, dura mater, brain tissue injury and bleeding, as well as the fixed position and osseointegration of postoperative alumina bioceramical materials implanted were compared, and the modeling success rate was compared after 8 weeks between the two groups. Results    Compared with the control group, the drilling time of the experimental group was shortened (P<0.01), the intraoperative complications such as periosteum, dura mater, brain tissue injury and bleeding were significantly reduced (P<0.05), and there was no displacement and loosening of alumina bioceramical materials after operation (P<0.05), and the material was well bonded to the skull, and the success rate of modeling was significantly increased (P<0.05). Conclusion    The modified method for skull defect model in rats has the advantages of short drilling time and less complications. It can greatly improve the success rate of model establishment and can effectively evaluate the bone repair performance of orthopedic implant materials in vivo.

Key words: Skull defect, Animal model, Alumina bioceramic, Rats