H锉联合回旋手机与ProFile镍钛系统拆除根充牙胶能力的比较研究

目的比较H锉联合同旋手机与ProFile镍钛系统在进行根管再治疗时拆除根管充填物的能力。方法选取24颗离体下前牙常规根管治疗后随机分为2组(每组12颗),分别采用H锉联合回旋手机和ProFile镍钛系统进行根充物的拆除,每组都使用氯仿。记录到达工作长度牙数、到达工作长度用时、根充物推出根尖孔牙数、发生并发症牙数及器械损耗数。最后纵劈牙齿,统计根管内残余充填物量。实验结果采用t检验和卡方检验。结果H锉联合回旋手机组到达根尖工作长度用时较短,与ProFile组间存在显著性差异(P< 0．01);两组根管内都有充填物残余;PorFile组在拆充过程中较少发生根充物被推出根尖孔的情况;ProFik器械的损耗率较高。结论ProFile器械不适用于拆除根充牙胶。

A comparison of H-files with reciprocal instruments and ProFile Ni-Ti system in the Re-treatment of Gutta-percha-filled root canals

Objective To compare the effectiveness of H-files with reciprocal instruments and ProFile during the removal of root canal filled gutta-percha. Methods A total of 24 canals from extracted single-rooted maxillary anterior teeth were divided into 2 groups. All the canals were accessed and then prepared with K-files and obturated with gutta-percha and iodoform paste in laterally condensation technique. After two weeks of obturation, re-treatment was performed with the following instruments: H-files with reciprocal instruments(group A); ProFile(group B).Chloroform was used in all groups. The time required to achieve the working length was recorded. The teeth were subsequently split longitudinally, photographs were taken with a digital camera and the remnants within the root canals after re-treatment were assessed. The amount of filling materials been pushed out of apex was also recorded. The results were compared by means of T test and Chi square test among the groups. Results All instruments can get to the working length. Group A was significantly faster than group B (P<0.01) to achieve the working length. All groups left gutta-percha inside the canal. The numbers of fillings been pushed out of apexes in group B was fewer than group A. The rate of wastage of ProFile was higher than H-files. Conclusion ProFile instruments were inadequate in removing the gutta-percha filling material from the root canals.