猫下颌尖牙根管治疗对牙正畸移动的影响  

An experimental study of the effects of root-canal treatment on orthodontic movement in cat cuspids

作　　者：龚向阳[1] 翦新春[2] 雷勇华[2] 姚征宇[1] 洪滔[1] 马德英[1] 

机构地区：[1]浙江省中西医结合医院,浙江杭州310003 [2]中南大学湘雅口腔医学院,湖南长沙410008

出　　处：《上海口腔医学》2007年第2期206-210,共5页Shanghai Journal of Stomatology

基　　金：杭州市科技发展计划项目基金(02B020)

摘　　要：目的:探讨经根管治疗牙的正畸移动可行性及牙根吸收的风险。方法:建立对经根管治疗牙进行正畸移动的动物模型,采用石膏模型测量、病理学和放射学方法评估正畸移动的距离及牙根吸收的程度。16只成年家猫的一侧下颌尖牙在全麻下开髓、拔髓,一次完成根管充填治疗术,随后在正畸弹簧的作用力(100-120g)下向远中作倾斜移动。8周后测量石膏模型上牙移动的距离,以及根管治疗牙与正常牙的组织学和放射学牙根长度。应用SPSS11．0软件包进行数据分析,均数比较采用配对t检验。结果:实验结果显示,在相同正畸力作用下,根管治疗牙与正常牙移动距离相近(P>0．05);组织病理学显示,根管治疗牙牙根的长度比正常牙小(P<0．05),但在放射学上,两者的长度无统计学差异(P>0．05)。结论:在本实验条件下,经根管治疗牙在正畸力作用下能与正常牙同样快速移动,组织学观察显示其根吸收的程度比后者略大。PURPOSE： To evaluate the effectiveness of orthodontic forces in moving teeth after root canal therapy and the risk of apical resorption which may happen during orthodontic movement in an animal model. METHODS： Under general anesthesia, root canal therapy was performed on the mandibular canines on one side of 16 adult cats. Tipping movement of the canines was induced with an orthodontic spring （100 to 120 g）. Eight weeks later, tooth movement was assessed from pre- and posttreatment mandibular casts, including measurement of root lengths in both radiographs and histological sections. All the data were analysed with SPSS 11.0 for windows . Student＇s t test was used for comparisons between paired groups. RESULTS： The results showed that teeth after root canal therapy and vital teeth moved similar distances when subjected to the same forces （P〉 0.05）. And teeth after root canal therapy had greater loss of cementum after tooth movement than vital teeth （P〈 0.05）, but without significant differences in radiographic root length （P〉0.05）. CONCLUSIONS： Teeth after root canal therapy can be moved orthodontically as readily as vital teeth when subjected to the same orthodontic forces under the conditions of the study .However, teeth after root canal therapy have more root resorption than vital teeth during orthodontic movement which may not be detected form the radiography.Supported by Research Fund of Science and Technology Development Project from Hangzhou City （Grant No. 02B020）.

关 键 词：正畸牙移动 根管治疗 牙根吸收 

分 类 号：R783.5[医药卫生—口腔医学]