大鼠牙齿空间移动评估及牙槽骨微观结构变化追踪研究  

Evaluation of tooth spatial movement and tracking of microstructural changes in the alveolar bone in rats

作　　者：钱心瑶 姜迪 谢玉婷 吴斌[5] 唐雯 陆玲波 李禹江 谢理哲 严斌[1,2,3,4] QIAN Xinyao;JIANG Di;XIE Yuting;WU Bin;TANG Wen;LU Lingbo;LI Yujiang;XIE Lizhe;YAN Bin(Department of Orthodontics,the Affiliated Stomatological Hospital of Nanjing Medical University,Nanjing 210029;State Key Laboratory Cultivation Base of Research,Prevention and Treatment for Oral Diseases,Nanjing 210029;Jiangsu Province Engineering Research Center of Stomatological Translational Medicine,Nanjing 210029;Oral Digital Medical Technology Engineering Center,Nanjing Medical University,Nanjing 210029;College of Mechanical and Electronic Engineering,Nanjing Forestry University,Nanjing 210037,China)

机构地区：[1]南京医科大学附属口腔医院正畸科,江苏南京210029 [2]口腔疾病研究与防治国家级重点实验室培育建设点,江苏南京210029 [3]江苏省口腔转化医学工程研究中心,江苏南京210029 [4]南京医科大学口腔数字化医疗技术工程中心,江苏南京210029 [5]南京林业大学机械电子工程学院,江苏南京210037

出　　处：《南京医科大学学报(自然科学版)》2025年第4期478-486,522,共10页Journal of Nanjing Medical University(Natural Sciences)

基　　金：国家自然科学基金(82371000,82071143,82101079);国家重点研发计划(2022YFC2402103,2023YFC2413605);江苏省重点研发计划(BE2022795);江苏省科学技术厅社会发展面上项目(BE2023836)。

摘　　要：目的:显微CT(micro-computed tomography,Micro-CT)活体扫描观测并量化正畸力下大鼠的牙齿移动,张力区及压力区骨小梁微观结构的连续变化情况。方法:对5只雄性8周龄SD大鼠的左侧上颌第一磨牙施加50 g矫治力,使用Micro-CT在加力前及加力后的不同时间点对大鼠进行活体扫描,在统一空间坐标系下计算大鼠正畸牙齿移动距离,并测量统计移动牙张力区及压力区的骨小梁微观形态和力学特性相关参数,分析其动态变化特征。结果:大鼠磨牙在0~3 d有明显位移,3~14 d移动速率下降,21~28 d速率增加(P<0.001);张力区及压力区多项骨小梁参数分别以7、14 d为转折点,骨体积分数(bone volume fraction,BV/TV)和骨小梁厚度(trabecular thickness,Tb.Th)先下降后升高,孔隙总体积[total volume of pore space,Po.V(tot)]、结构模型指数(structure model index,SMI)、骨小梁间隙(trabecular separation,Tb.Sp)和分形维数(fractal dimension,FD)先升高后下降,牙移动前期张力区增量斜率较压力区更大,牙移动后期BV/TV、Po.V(tot)、SMI和Tb.Sp数值在张力区及压力区差异有统计学意义(P均<0.05)。结论:大鼠正畸牙移动具有三阶段性;张力区及压力区骨小梁微观结构改建存在差异,骨量及骨质量均先降低后升高,并分别在7 d和14 d前后达到最低点;张力区的骨吸收活跃期较早,张力区牙槽骨骨形成滞后于压力区骨吸收。Objective:This study was aimed to observe and quantify the continuous changes in dental movement and trabecular microstructure in both tension and pressure zones of rats under orthodontic force using the in vivo micro-computed tomography(Micro-CT)scanning.Methods:A 50 g orthodontic force was applied to the left maxillary first molar of five 8-week-old male SD rats.The rats were scanned in vivo at different time points using Micro-CT.The distance of orthodontic tooth movement was calculated in a unified spatial coordinate system.Additionally,trabecular micro-morphological and mechanical property-related parameters in the tension and pressure zones of the moving teeth were measured and statistically analyzed.Results:There was significant displacement of the rat molars within the first 0-3 days,with a decrease in movement rate between 3 and 14 days,followed by an increase in rate between 21 and 28 days(P<0.001).Multiple trabecular parameters in both tension and pressure zones showed turning points at 7 days and 14 days,respectively.Specifically,the values of bone volume fraction(BV/TV)and trabecular thickness(Tb.Th)were first decreased and then increased,while those of total porosity volume[Po.V(tot)],structure model index(SMI),trabecular separation(Tb.Sp),and fractal dimension(FD)exhibited the opposite trend.During the early stage of tooth movement,the slope of increase in trabecular parameters was greater in the tension zone compared with the pressure zone.In the later stage of tooth movement,there were significant differences in the values of BV/TV,Po.V(tot),SMI,and Tb.Sp between the tension and pressure zones(P all<0.05).Conclusion:Orthodontic tooth movement in rats occurs in three stages.There are differences in trabecular microstructure remodeling between tension and pressure zones,with bone mass and bone quality both decreasing first and then increasing,reaching their lowest points around 7 days and 14 days,respectively.The active phase of bone resorption in the tension zone occurs early,and bone formation in

关 键 词：MICRO-CT 正畸牙齿移动 骨小梁 微观结构 追踪研究 

分 类 号：R783.5[医药卫生—口腔医学]