应用BMSCs/A-PCPC复合物进行种植前牙槽嵴保存的实验研究

Establishment and experimental study of alveolar preservation before dental implantation in Beagle dogs

目的:建立种植前牙槽嵴保存的动物模型,观察应用组织工程骨进行牙槽嵴保存的效果。方法:抽取Beagle犬骨髓,体外分离培养、成骨诱导、扩增骨髓基质细胞(bone marrow stromal cells,BMSCs),准备活性磷酸钙骨水泥(activeporous calcium phosphate cement,A-PCPC),体外构建骨髓基质细胞/活性磷酸钙骨水泥复合体(BMSCs/A-PCPC)的复合物。拔除4只Beagle犬双侧下颌第二、三、四前磨牙,随机选取一侧植入BMSCs/A-PCPC复合物作为实验组,另一侧作为对照组(空白对照组、自体骨组、单纯A-PCPC组)。于术后1 d及术后4、12周进行X线片观察及CT扫描分析。并于12周时取牙槽窝组织,进行组织学观察,采用SPSS17.0软件包对数据进行统计学分析。结果:术后4周X线片观察,BMSCs/A-PCPC复合物组较单纯A-PCPC组、自体骨组密度高。12周时硬组织切片检测,BMSCs/A-PCPC复合物组成骨活性高于其他各组。螺旋CT分析结果显示,各组牙槽嵴均发生了不同程度的吸收。12周时,A-PCPC组牙槽嵴高度的减少值较对侧的单纯A-PCPC组、自体骨组、空白组牙槽显著降低(P<0.05)。结论:建立的种植前牙槽嵴保存的动物模型合理可行,BMSCs/A-PCPC复合物可以作为种植前牙槽嵴保存的组织工程骨材料。

PURPOSE： To establish the model of alveolar ridge preservation after tooth extraction for dental implant replacement, and to observe the effect of tissue engineered bone on osseointegration. METHODS： Isolated BMSCs were expanded and osteogenically induced in vitro. The tissue engineering complex was constructed with BMSCs/A-PCPC in vitro. Six extraction sockets, with three on each side, were created in the mandibles of four Beagle dogs by extracting the second, third and fourth premolars. BMSCs/A-PCPC were placed on one side of the extraction sockets, while autogenous bone, A-PCPC and nothing were placed on the other side as control. X-ray and CT scans were conducted lday, 4 and 12 weeks after operation to detect the change of the alveolar ridge.The bone of sockets were harvested at 8-week post- implantation and subject to histological for evaluating. SPSS17.0 software package was used for data analysis. RESULTS： Radiographs demonstrated higher radiodensity in group of complex than in simple materials group, autogenous bone groupafter 4 weeks. Hard tissue biopsy at 12-week showed that bone activity of BMSCs/A-PCPC complex was better than the other groups.Spiral CT analysis showed that alveolar ridge of each group experienced a certain degree of absorption. At 12-week, the alveolar ridge height reduction values in A-PCPC group was smaller than in A-PCPC group, autogenous bone group and blank group （P〈O.05）. CONCLUSION： The BMSCs/A-PCPC complex is favorable for preservation of alveolar ridge. Supported by Youth Medical Fund of Bureau of Health of Shanghai Municipality （2009Y082）, Innovation Program of Science and Technology Development Fund of Pudong New District（PKj2010-Y01） and Youth Fund of Pudong New District （PW2011B-13）.