牙种植外科骨收集器内骨碎屑成骨活性的研究

Osteogenetic Activity of Collected Bone Chips in Dental Implantation

目的:通过组织学、体外细胞培养和自体移植研究收集骨的成骨活性并探讨其作为骨组织工程中种子细胞来源的可能性。方法:2003年10月至2005年10月,应用收集器收集种植窝制备时钻出的骨碎屑10例,取样本部分骨屑脱钙后行组织学观察;样本剩余部分应用组织贴块法行体外培养,观察细胞的游出、增殖和传代情况,应用碱性磷酸酶染色和连续培养矿化结节染色进行鉴定,并行扫描电镜观察。选择种植体颈部骨缺损7处,应用收集骨即刻移植修复,二期手术时观察移植物成活情况并刮取少许行组织学检查。结果:光镜下观察收集物以骨组织为主,10例样本中8例成功培养出成骨样细胞,碱性磷酸酶阳性染色率超过70%,体外连续培养茜素红染色可见桔红色结节,扫描电镜可见细胞贴附于纳米羟基磷灰石并活跃生长。牙种植二期手术时原缺损处已覆盖成熟骨质,组织学显示为密质骨。结论:收集骨具有良好的成骨活性,可用于修复种植体周围小的骨缺损,也可作为骨组织工程中种子细胞的来源。

Objective： To evaluate the osteogenetic activity of bone chips recovered from dental implant surgery and to discuss the possibility as a source of seed cells in bone tissue engineering. Methods： From Oct 2003 to Oct 2005, 10 samples of collected bone chips were harvested with a designed instrument when 10 dental implants were installed into 10 patients without peri-implant defects. Part of each sample was examined by light microscopy after decalcification, and the rest were cultured in vitro. The biological characteristics of cultured cells were examined by morphological observation, staining of alkaline phosphatase（ALP）, staining of red alizarin and scanning electron microscopy（SEM）. Seven peri-implant dehiscences which occurred in 7 recruited patients during the dental implantations were repaired with the collected bone chips. In the second surgical stage, some of the bone graft around the cover screw was obtained for histological observation. Results： The histological observation showed that all samples contained bone, coagulum and a little marrow. Osteoblast-like cells were successfully cultured in vitro in 8 samples, which were mainly spindle-shaped and polygonalshaped. Being histochemical stained, more than 70% cells showed the positive stain of ALP, and many minerlization nodes formation after cultured in conditioned DMEM. SEM showed that tissue engineered bone was formed when the osteoblasts cultured with nanophase hydroxyapatite. In the second surgical stage, the defects were successfully augmented, and the histological observation showed that cortical bone were built in the collected bone graft. Conclusion： The collected bone debris has good osteogenetic activity, and it can be used to fill small bone defects in dental implantation and act as a source of osteoblasts in bone tissue engineering.