Abstract: Objective: The purpose of this study was to evaluate whether mice with knock out osteoprotegerin gene (Opg-KO) was associated with the age-related changes of mandible. Methods:  6-week-old and 12-month-old Opg-KO mice (n=6) and WT mice (n=6) were comprised in this study. Micro-CT was used to evaluate  the osteoporosis degree of the ROI (the region of interest). Results: Compared with WT mice, Opg-KO mice developed serious bone resorption in the cancellous bone of the mandible, the neck of condyle, the angle of mandible and the incisors at 6 weeks, and the bone resorption became more serious at 12 months. The Tb. Th, BMD, BV/TV of the cancellous bone decreased obviously, but the Tb. Sp increased obviously. The BMD and BV/TV of the cortical bone decreased obviously. Conclusion: OPG deficiency causes serious bone destruction in mouse mandible. The more severe bone destruction positive related to increased age. The bone remodeling of the mandibular cancellous bone are more remarkable.

Key words: osteoprotegerin, gene knock-out, age-related, Micro-CT

摘要： 目的：基于Micro-CT评价骨保护素基因敲除（Opg-knockout，Opg-KO）型小鼠与野生型(wild type，WT) 小鼠的下颌骨微结构增龄性变化，以便更好了解小鼠下颌骨的增龄性骨质改建情况。方法：分别采集6周、12月龄Opg-KO小鼠和WT小鼠各6只，采用Micro-CT扫描观察小鼠下颌骨三维结构，对感兴趣区域根分叉部位松质骨及前牙颏孔前缘区皮质骨骨微结构进行定量分析。结果：与WT小鼠相比，Opg-KO小鼠6周时第一磨牙根分叉处松质骨、髁突颈部、下颌角处、前牙颏孔前缘区均出现了明显的坑凹状吸收；12月时，这些区域破坏愈发严重，甚至出现穿孔；根分叉松质骨区域骨小梁平均厚度、骨密度、骨体积分数明显降低（P<0.05），骨小梁分离度明显升高（P<0.05）；前牙颏孔前缘区皮质骨骨密度及骨体积分数明显降低（P<0.05）。结论：OPG缺失引起小鼠下颌骨发生严重的骨质破坏，随着年龄增加骨质破坏程度越发严重，并且松质骨骨微结构改变更显著。

关键词: 骨保护素；  , 基因敲除；  , 增龄性；  , Micro-CT

CLC Number: 

• R782