根管冠部预处理对磨牙根管工作长度的影响

目的:探讨根管冠部预处理对磨牙根管工作长度测量的影响。方法:将47例成人牙髓炎患者的48颗磨牙随机分成2组,第1组为常规治疗组,共24颗磨牙74个根管,常规去腐开髓,插入15#K型锉至根管内到根尖区感觉有明显阻力为止,标记,采用分角投照技术摄X线片。第2组为根管冠部预处理组,24颗磨牙75个根管。暴露根管口后,先用Profile.0625#、20#镍钛机用器械扩开根管口,预备根管颈1/3,再同样插针摄片,分别测量2组X线片上K锉尖端至根尖的距离。将资料进行Logistic单因素和多因素分析。结果:根管冠部预处理后磨牙根管工作长度测量的准确性较常规组有显著提高(P<0.05),K锉尖端至根尖的距离与年龄、性别、磨牙的位置无显著相关,而与颌位显著相关,上颌磨牙的准确性明显好于下颌磨牙(P<0.05)。结论:根管冠部预处理可提高磨牙根管工作长度测量的准确性。

The effect of coronal preflaring on the working length measurement of root canals in molars

PURPOSE: To study the influence of coronal preflaring of root canal on the working length measurement in molars. METHORS: 48 molars from 47 adult patients with pulpitis were divided into two groups randomly. 74 root canals of 24 molars were examined in Group 1. After preparing an access cavity, the root canal orifices were located. A 15# K-type file was inserted into root canal to detect resistance at the apical region . 75 root canals of 24 molars were examined in Group 2. Before testing the apical resistance,a size 25# and 20# ProFile.06 taper NiTi rotary instrument was used to enlarge the canal orifice and flare the coronal portion of the root canal. After placing 15# K-type files, a radiograph was taken with the bisecting-angle technique. The distance between the tip of the file and the radiographic apex was measured on the radiographs. Statistical analysis of univariate and multiple logistic regression were carried out for analysis. RESULTS: There was a significant difference between the two groups(P<0.05), there were more accurate measurements in Group 2 than in Group 1. No statistical correlation was found between X-ray measurements and age, sex and the position of molars,while there was significant correlation between maxillary molars and mandibular molars (P<0.05). CONCLUSION: Preflaring the coronal portion of the root canals could significantly increase the accurate measurements of the working length of root canals in molars.