超高分子量聚DL乳酸对成骨细胞活性及新骨生成的影响

目的：研究超高分子量聚DL乳酸材料对成骨细胞活性及其在骨创愈合过程中对新骨生成的影响。方法：（1）体外实验：在超高分子量聚DL乳酸材料浸提液和标准培养基中培养乳鼠成骨细胞，采用四甲基偶氮唑盐微量酶反应比色法检测成骨细胞的活性和功能。（2）体内实验：在犬下颌骨体部制造人工骨折模型，用聚DL乳酸制作的夹板螺钉固定骨折处，在扫描电子显微镜下观察骨折线处的新骨沉积情况。结果：（1）超高分子量聚DL乳酸对成骨细胞在3d时毒性为3％，在1周、2周时均为0；实验组和对照组的A组在3d、1周、3周时差异均无显著性。（2）术后3个月时，电镜下可见聚DL乳酸材料与骨组织之间有大量新骨形成。结论：超高分子量聚DL乳酸对成骨细胞的活性及新骨生成均无影响，可作为体内植入物及骨组织工程的载体材料。

Influence of super high molecular weight poly D,L-lactic acid on viability and new bone formation of osteoblasts

OBJECTIVE: To investigate the influence of the viability and new bone formation of osteoblasts by the super high molecular weight poly D,L-lactic acid (SHMW-PDLLA). METHODS: 1. The osteoblasts derived from neonatal rat were grown and maintained at steep of SHMW-PDLLA and normal culture medium. The viability and function of the osteoblasts were measured with MTT array. 2. The plate and screws made of SHMW-PDLLA were implanted and fixed at the artificial fractured mandible of dogs. Specimens were gained at 3 and 6 months and examined with macroscopy and SEM. RESULTS: 1. There is no significant difference of OD values between the experimental group and the control group (P > 0.05). The SHMW-PDLLA isn't toxic to osteoblast at 1 week and 2 weeks, and the toxicity is 3% at 3 days. 2. There were a lot of new bone formed between the implanted SHMW-PDLLA plate and bone tissues under SEM. CONCLUSION: SHMW-PDLLA hasn't pathological influence on the viability and new bone formation of osteoblasts and it is feasible in tissue engineering of bone.