Objective:Whether allogeneic bone mesenchymal stem cells (allo-BMSCs) are completely immune privilege and play a biological role in vivo or not is still a controversial issue.This experiment studied the osteogenesis capacity of allogenic tissue-engineered bone (allo-TEB) and the feasibility of repairing canine critical-sized mandibular defects by allo-TEB.The immune response of recipient was also been explored at the same time.