不同镍钛器械预备根管后根尖偏移的锥形束CT比较

Comparative of CBCT for Root Tip Migration after Root Canal Preparation with Different Niti Instruments

目的对不同镍钛器械预备根管后的根管偏移情况以及其中心定位率采用锥形束CT(CBCT)的方式进行测量,分析M3、Protaper以及S3的根管预备情况。方法从所有离体牙中,选择符合本次研究标准的30例作为本次研究对象,按照随机的方式将其分成3个小组,A组采用M3按冠向下的方法进行预备,预备至#30/0.04,B组采用Protaper进行预备,将其预备至#30/0.04,C组采用S3进行预备,将其预备至#30/0.04。对所有预备的根管采用CBCT进行测量。测量内容:先找到所有根管后距离根尖3 mm位置,然后测量其远近的根管壁厚度情况,再通过Gambill所提出的相关公式,计算所有根管的偏移量以及轴中心率。对3组的测量情况采用相关统计软件进行比较。结果3组根管偏移量以及轴中心率比较,差异无统计学意义(P>0.05)。根管预备前后,3种不同的镍钛根管预备的偏移量以及轴中心率比较,差异无统计学意义(P>0.05)。结论虽然M3、Protaper以及S3预备根管后的根管偏移量较小,但3种器械都能够基本保持原有的形态。

Objective To measure the root canal migration and its center positioning rate after root canal preparation with different niti instruments by CBCT,and to analyze the root canal preparation of M3,Protaper,and S3.Methods From all the teeth in vitro,30 cases that met the research criteria were selected as the subjects of this experimental study.They were randomly divided into three groups.Group B used Protaper and prepared it to#30/0.04.Group C takes S3 and prepares it to#30/0.04.All prepared root canals were then measured using CBCT.The content of measurement is to find the position of all root canals at the distance of three millimeters from the root tip,and then measure the thickness of the root canal wall near and far.Then,through the relevant formula proposed by Gambill,the offset and axial center rate of all root canals are calculated.Finally,the measurements of the three groups were compared by relevant statistical software.Results Compared with the three groups,it was found that there was no significant difference in the offset results and the axial center rate results(P>0.05).Before and after root canal preparation,there was no significant difference between the three kinds of niti in the deviation of root canal preparation and the axial center rate(P>0.05).Conclusion Although the displacement of the root canal after root canal preparation by M3,Protaper and S3 is small,all three instruments can basically maintain the original shape.