上海交通大学学报(医学版)

• 论著(基础研究) • 上一篇    下一篇

Micro-CT动态观察大鼠牙齿移动过程中微观结构的变化

陈鹏 1, 2,杨风雪 1, 2,周建萍 1, 2,戴红卫 1, 3   

  1. 1. 重庆医科大学附属口腔医院,重庆 401147;2. 口腔疾病与生物医学重庆市重点实验室,重庆 401147;3. 重庆市高校市级口腔生物医学工程重点实验室,重庆 401147
  • 出版日期:2017-02-28 发布日期:2017-02-28
  • 通讯作者: 周建萍,电子信箱:79712874@qq.com。
  • 作者简介:陈鹏(1990—),男,硕士生;电子信箱:963167867@qq.com。
  • 基金资助:

    重庆市卫生局自然科学基金(2011-1-057,2012-2-132);重庆市渝北区科学技术委员会自然科学基金[2014(社)10号]

Micro-structure changes in rat tooth movement process through micro-computed tomography dynamic observation

CHEN Peng1, 2, YANG Feng-xue1, 2, ZHOU Jian-ping1, 2, DAI Hong-wei1, 3   

  1. 1.Stomatological Hospital of Chongqing Medical University, Chongqing 401147, China; 2.Chongqing Key Laboratory of Oral Diseases and Biomedical Sciences, Chongqing 401147, China; 3.Chongqing Municipal Key Laboratory of Oral Biomedical Engineering of Higher Education, Chongqing 401147, China
  • Online:2017-02-28 Published:2017-02-28
  • Supported by:

    Natural Science Foundation of Chongqing Health Bureau,2011-1-057,2012-2-132;Natural Science Foundation of Chongqing Yubei District Science and Technology Commission,2014(Science) No.10

摘要:

目的 · Micro-CT活体扫描动态观察不同矫治力作用下,大鼠牙齿移动过程中微观结构的变化。方法 ·选择 8周龄雄性SD大鼠15只,随机分成3组,每组5只。对大鼠左侧上颌第一磨牙分别施加20、50、100克力(1克力=0.009 8 N)的矫治力,持续加载14 d。在加力后的0、3、7、10、14 d,用Micro-CT对大鼠进行活体扫描,测量每个时间点牙根表面陷窝体积及骨小梁结构参数。结果 ·加力3 d,各组牙根表面陷窝体积略有增加,第3~10 日明显增加,第10日后增加缓慢;第7~14日,100克力力值组牙根表面陷窝体积显著大于其他2组(P<0.05)。随着加力时间的推移,压力侧牙槽骨的骨体积分数逐渐减小,骨小梁形态变细小、数量减少,骨小梁间隙先减小后增宽,骨小梁有自板状向杆状转变的趋势,牙槽骨发生吸收,各力值组间变化趋势一致。结论 ·不同矫治力值都会引起牙根吸收,吸收规律表现为缓慢期、快速期、稳定期,过大的矫治力会导致更多的牙根吸收;牙齿移动过程中,压力侧牙槽骨均会发生吸收改建,其变化量与力值大小无明显相关性。

关键词: Micro-CT, 正畸牙齿移动, 动态观察, 微观结构

Abstract:

Objective · To observe the micro-structure changes in rat tooth movement process under different force values through Micro-CT dynamic observation. Methods · Fifteen SD adult male rats at the age of 8 weeks were divided into three groups randomly (n=5), with the left maxillary as the experimental side and the nickel titanium coil springs, fixed between the first molar and incisor where thrust augmentation was conducted respectively by 20, 50 and 100 gf (1gf=0.009 8 N) for continuous 14 d to it. Rat scanning in vivo through Micro-CT was carried out at day 0, 3, 7, 10 and 14 after force values were loaded on. The root resorption crater volumes and structure parameters for bone trabecula at different time points were measured. Results · Three days after thrust augmentation was conducted, root resorption crater volume for each group had a slight increase and an obvious increase occurred from the 3rd day to the 10th day, and then a slow increase happened 10 d later; from the 7th day to the 14th day, root resorption crater volume for 100 gf stress group was obviously greater than those of the other groups with statistical differences (P<0.05). With time for thrust augmentation passing by, bone volume fraction at the pressure side of alveolar bone decreased gradually and bone trabecula morphology became tiny and exiguous; besides, bone trabecula gap became narrow first and broad afterwards, and trabeculae trended to change from clintheriform to rhabditiform. Furthermore, alveolar bone resorption occurred in each stress group with consistent tendency. Conclusion · Different orthodontic force values all can cause root resorption, which experiences lag phase, rapid phase and stationary phase. Over-loaded orthodontic force induces more root resorption. During the process of the tooth movement, the pressure side of alveolar bones appears reconstruction and absorption, whose variation is not related with force degree.

Key words: Micro-CT, orthodontic tooth movement, dynamic observation, micro-structure