关键词: 矿化胶原, 　镁钙合金, 　拔牙位点, 　骨再生

Abstract:

Objective　To study the feasibility of mineralized collagen composite calcium magnesium alloy used in the preservation of dog tooth extraction site.　Methods　Forth premolars of eight mongrel dogs from the left and right sides of the mandible were extracted, which then resulted in a total of 32 extraction sockets that were then randomly divided into two groups, A and B, with 16 extraction sockets in each group. Group A was implanted with the composite material of mineralized collagen and calcium magnesium alloy, group B was only implanted with mineralized collagen material, the dog was sacrificed 12, 24 weeks later to prepare tissue specimens. The healing of sockets was evaluated by gross observation,CBCT and X-ray microscopes. The damage of liver and kidney tissues was observed by histological sections of liver and kidney.　Results　After implantation of the two groups of materials in the extraction nest, with the healing of the tooth socket, the material gradually degraded and absorbed, the new bone tissue continued to form. At 12 weeks postoperatively, the relative bone mineral density and the number of new bone tissues in experimental group A were significantly higher than those in control group B (P<0.05). At 24 weeks after operation, the number of new bone tissue in group A and B increased gradually, and the difference of bone mineral density between the two groups was not significant (P>0.05).　Conclusion　The composite material of mineralized collagen and calcium magnesium alloy can be used for preservation of dog 's tooth extraction site, which promotes the regeneration of new bone and reduces the absorption of alveolar ridge.

Key words: Mineralized collagen, 　Calcium magnesium alloy, 　Tooth-extraction site, 　Bone regeneration