Abstract: Objective To repair the skull defects by using autogenous skull bone dust grafting and membrane guided regeneration technology, and to investigate its histological evolution. Methods Fifty New Zealand white rabbits were selected. A whole thick defect with the diameter of 1 cm was created in the parietal bone of every rabbit. The defect was grafted with autogenous skull bone dust and two pieces of absorbable membrane on two side. After 2, 4, 6, 8, 12 weeks, the defects were harvested for histological observation. Results Two weeks after operation, a large number of bone meal was observed in the defect area. Inward infiltration of inflammatory cells, capillaries and fibroblasts were observed. Bone meal was swallowed in the central area, new bone was formed in the surrounding area and a clear boundary was observed between the two area. Four weeks after operation, the boundary had moved a lot to the central area. New woven bone was thickened, the connection between the woven bone became more closely. Tissue and cell components had no obvious change compared with 2 weeks after operation. Six weeks after operation, bone meal was almost absorbed, the woven bone became thicker and the connection was more closely. Eight weeks after operation, no bone dust could be observed, a monolayer new bone was formed in the central area. The woven bone in the surrounding area was relatively thick and closely connected with normal bone. The primary bone marrow cavity was formed. Twelve weeks after operation, double new bone was observed in the central area. New bone remodeling and mature bone marrow cavity were also observed. The morphology and composition of bone marrow cavity had no difference compared with normal bone. Conclusion Histological evolution of autogenous bone dust grafting and membrane guided regeneration technology to repair skull defects is guided and induced bone regeneration.

Key words: Membrane, Autogenous skull bone dust, Cranial defects, Transplantation, Repairment, Histological evolution