富血小板血浆与多孔矿化骨修复兔下颌骨双皮质骨缺损作用

目的探讨富血小板血浆(PRP)与多孔矿化骨(BPBM)修复下颌双皮质骨缺损作用。方法 54只健康白兔分为3组,制作下颌双皮质骨缺损模型,治疗1组植入PRP+BPBM+GBR,治疗2组植入BPBM+GBR,对照组植入明胶海绵,用X线、光学显微镜、电子显微镜观察术后4、8、12周骨缺损修复情况,测定血中碱性磷酸酶(ALP)、钙磷变化。结果 PRP血小板为全血4.19⁴.43倍;X线片示在4、8、12周时治疗1和2组骨密度明显高于对照组;HE染色见在4周时治疗1组缺损边缘有少许新骨生成,移植物部分降解,治疗2组新骨形成较少;在8周时治疗1组新骨数量明显多于治疗2组;12周时治疗1组充填物吸收被新骨代替,新生骨骨小粱和骨陷窝增多;治疗2组成骨细胞和新骨数量比治疗1组少;对照组新骨形成明显减少。电镜发现,治疗1组各时间点成骨细胞突起和向移植物浸润能力、成骨细胞内线粒体和粗面内质网数量多于治疗2组,治疗2组成骨细胞内线粒体数量和成骨细胞突起向移植物浸润能力强于对照组。在4、8、12周时治疗1组和治疗2组碱性磷酸酶和钙磷含量与对照组比有显著性差异。结论联合PRP和BPBM及GBR技术对下颌双皮质骨缺损有良好修复能力,其作用与PRP中高浓度血小板分泌生长因子和BPBM多孔支架结构有关。

Platelet-rich plasma and bovine porous bone mineral combined with guided tissue regeneration in the treatment of mandibula bicortical bony defects in rabbit

Objective To investigate the effectiveness of the combination of platelet-rich plasma （PRP） ,bovine porous bone mineral （BPBM） in treating mandibula bicortical bony defects in rabbit. Methods Fifty-four healthy rabbit participated in the study and they were divided into 3 groups. The 11 millimeter diameter rotundity bicortical bone defects were made surgically on mandible and treated with either the combination of PRP ＋ BPBM ＋ GBR （ group 1 ） or the combination of BPBM ＋ GBR （ group 2） or glutin sponge （ control group）. Changes of the bone defects were observed by X-ray,optical microscopy,electron microscopy 4,8 and 12 weeks after operation. The alkaline phosphatase （ALP） and calcium and phosphorus contents in blood were measured and analyzed. Results The platelet concentration of PRP was 4.19 to 4.43 times that of the whole blood. The X-ray demonstrated that the bone density in group 1 and 2 was obviously higher than that of the control group during the treatment. HE staining showed that in group 1 ,the new bone formed at the 4th week and the transplants partly degraded while there was less new bone formation in group 2. At the 8th week,the new bones in group 1 were obviously more than group 2. After 12 weeks,the fillings of group 1 were absorbed and replaced by new bones and the tra-becular bones and bone lacuna increased while in group 2,the gegenbaur ceils and the newly-formed bones were significantly less than group 1 and the new bones in the control group were even less. According to the transmission electron microscopic study,the osteoblasts were found active during the treatment. The number of mitochondrium and rough endoplasmic reticulum in osteoblasts of group 1 was larger than group 2 and control group and the infiltration capacity was better. The control group proved to be the worst. Both group 1 and 2 modalities resulted in significant enhancement of ALP and calcium and phosphorus in blood at week 4,8 and 12 compared with control group. Conclusions The results suggest that the combination of PRP,BPBM and GBR provides a significant regenerative effect on re-pairing the bicortical bony defects in rabbit. The effects are associated with the high concentration of platelet and abundant growth fac-tors in PRP,and the porous scaffold bone structure.