Raypex5根管长度测量仪准确性的临床及体外实验研究

目的：研究不同根管内容物（17％EDTA凝胶、生理盐水、5．25％次氯酸钠溶液）和根尖孔面积大小对Raypex5根管长度测量仪测量准确性的影响。方法：选取需要拔除的60颗单根管患牙，采用Raypex5根测仪在不同根管介质环境下，测量根管工作长度（EwLl），拔除患牙后在体视显微镜下测得根管实际工作长度（L1）；并建立体外模型，测量不同根尖孔面积（s）、根管工作长度（EWL2）和实际根管长度（L2），对根管在3种介质环境下Raypex5根测仪所测长度行单因素方差分析，与实际根管长度比较采用配对t检验；对根尖孔面积与Raypex5电测法测量值偏差之间的关系采用直线相关分析。结果：①．三组不同根管介质中的根管长度测量值之间差异无统计学意义（P〉0．05）。②．不同介质的根管长度测量值与根管实际长度之间的偏差无统计学意义（p〉0．05）。③．当根尖狭窄破坏后，根尖孔面积与根测仪测量值的偏差之间存在线性相关关系，（P〈0．0D。结论：Raypex5根管长度测量仪的准确性不受根管内介质的影响。当根尖狭窄被破坏后，根尖孔面积对Raypex5测量准确性有影响，临床上对根尖有吸收破坏或根尖未发育完全的患牙采用Raypex5电测法测量时，应谨慎参考根管工作长度值。

A clinical and vitro research on accuracy of Raypex 5 electronic root canal length measurement device

Objective： To evaluate effect of three kinds of irrigations （17 % EDTA,0.9 % physiological saline solution, 5.25 %sodium hypochlorite solution）and the influence of areas of apical foramen on Raypex5 measurement accuracy. Method： Choosing 60 single canal teeth, we measured the root canal work long （EWL1）in different irrigations in vivo using Raypex5 root canal length measuring instrument. After pulling out the teeth, we measured the root canal actual working length （L1） in the asana microscope. Established in vitro model,we measured different areas Of apical foramens （S） and its corresponding measurement of the tube length （EWL2）, and the actual length of root canal work （L2）. We analyzed three groups EWL1 in three kinds of medium environment by one-way ANOVA, the actual length of root canal by matching t test using SPSS software for 12.0. We applied the straight-line method for analyzing the area of apical foramen and the measuring de- viation. Result： 1.There was not statistically significant （P 〉0.05） between the length measured value differences in different irrigations using Raypex5.2.There was not statistically significant （P 〉0.05） between the length using Raypex5 and the actual length of root canal. 3.The accuracy of Raypex5 and the area of apical foramen had significant linear correlation when the apical constriction was destroyed. Then the linear regression equation was L= 0.105＋0.120S （F=30.660, P 〈0.01）. Conclu- sion：The accuracy of measurement of Raypex5 was not influenced by root canal media. The size of apical foramen has little effect on the accuracy of Raypex5 if the apical constriction is intact. However the measurement of Raypex5 should be used carefully when the apical constriction was destroyed.