应用螺旋扩弓器牵引兔下颌中缝后新骨的OPG及RANKL的表达

目的:利用螺旋扩弓器进行下颌正中联合横向牵张成骨,扩展下颌间隙,并探讨在机械张力作用下新骨组织中骨保护素(Osteoprotegerin,OPG)、破骨细胞分化因子(Receptor or Activator of NF-KB Ligand,RANKL)表达规律.方法:建立兔下颌骨正中联合牵张成骨模型,用免疫组化方法检测牵张后1d、牵张后4d、固定后1w,固定后4w、固定后12w的牵张区新生骨组织中骨保护素(OPG)、破骨细胞分化因子(RANKL)不同时期的分布和表达.结果:下颌正中联合牵张成骨除一只外,其余实验动物均成功,牵张平均量为4mm,牵张成骨1d和牵张成骨4dOPG的阳性细胞数百分比逐渐增加,固定1w到12w组织中阳性细胞数百分比逐渐减少,RANKL阳性细胞数的百分比仅在牙缝关闭后与对照组有差异,其余各时间点均无明显差异.结论:下颌正中联合横向牵张成骨是扩展下颌间隙的一种行之有效的方法.机械牵张力能够促进OPG表达,OPG可能在牵张成骨的早期起一定的抑制破骨并促进调节新骨形成作用,RANKL则与骨改建有关,发挥一定的作用.

Expression of OPG and RANKL in new bone by using expansion screw on rabbit mandibular midline

Objective： Using expansion screw to create intra-arch space in the mandibular arch to distract mandibular midline,and exploring the expression of disciplinarian of osteoprotegerin ligand（OPG）,receptor activator of NF-κB ligand（RANKL） in the new bone tissue with mechanical tension.Methods： Construct rabbit model of mandibular midline distraction osteogenesis,expression and distribution of 0PG and RANKL in different periods were detected by immunohistochemical method in distraction zone.Results： Mandibular midline distraction was completed successfully in all experimental animals and the distraction average amount was 4mm.At 1d and 4d after distraction,1w after fixed distraction zone showed strong positive staining of OPG,and then wore off gradually at 1w after fixed.Weak signals of RANKL could be detected after the teeth sew closed only.The rest of the time were not significantly positive.Conclusions： Mandibular midline distraction osteogenesis is an effective method to creat intra-arch space in the mandibular arch,for the gap.Mechanical tension can promote the expression of OPG,OPG may inhibit osteoclasts and promote new bone formation early,RANKL is related to bone remodeling,play a role.