不同年龄段小鼠下颌前导后髁突骨骼改建差异的研究

Expression of bone remodeling in mice condylar during mandibular advancement andits differences between different ages

目的:观测小鼠间歇性下颌前导后髁状突的形态学变化,比较不同年龄段的组织改建差异,为下颌前导的矫治时机和策略提供理论依据。方法:在4 周龄和8 周龄BABL/c雌鼠上建立间歇性下颌前导模型,于下颌前导后的14 d和28 d取颞下颌关节标本行Trap染色、Godener三色染色、微型计算机断层扫描(Micro-CT)技术来研究髁突破骨细胞及成骨细胞变化和骨骼形态学变化。结果:28 d时4 周龄组相对于28 d时8 周龄组,骨体积分数(BV/TV)和骨小梁厚度(TB.Th)减小,骨小梁间距(TB.Sp)增大(P<0.05)。骨小梁数量(TB.N)无明显差异(P>0.05)。14 d时4 周龄组相对于14 d时8 周龄组以及14 d时4 周龄组相对于28 d时4 周龄组,每视野中破骨细胞和成骨细胞数升高(P<0.05)。结论:小鼠导下颌向前与髁突骨骼改建有密切联系,不同年龄段差异显著。

Objective： To observe histomorphology changes of condyle and differences between young and adult through mandibular advancement intermittently so as to provide the opportunity and strategy of mandibular advancement. Methods： Mandibular advancement model was established on 4 weeks old and 8 weeks old BABL/c female rats. The TMJ samples were harvested at the 14 th and28th days and stored for Trap staining and Godener trichrome staining and Micro-CT scan. Results： Compared with those at 28 th day of the 8-week-old group,the expression at 28 th day of the 4-week-old group was as follows： BV/TV and TB.Th decreased; Tb.Sp increased（P〈0.05）; TB. N was not different（P〉0.05）. Compared with those at 14 th day of the 8-week-old group,the expression at14 th day of the 4-week-old group was as follows： the number of Trap positive osteoclasts and the number of osteoblasts were all increased（P〈0.05）. Compared with those at 28 th day of the 4-week-old group,the expression at 14 th day of the 4-week-old group was as floows： the number of Trap positive osteoclasts and the number of osteoblasts were all increased（P〈0.05）. Conclusions：Bone remodeling on rats is related with mandibular advancement and the expression has significant differences between different ages.