摘要
目的探讨逐步后退法、逐步深入法、被动逐步后退法(超声波与手用器械联合应用)三种不同方法预备后牙细弯根管对根管壁的清理能力及操作时间的差别。方法应用逐步后退法、逐步深入法、被动逐步后退法(超声波与手用器械联合应用)对45个新鲜拔除的人恒磨牙近中颊侧根管进行预备,并记录操作时间,将牙根纵向劈开,分为根冠1/3、根中1/3及根尖1/3,扫描电镜下评价其根管内壁牙本质碎屑和玷污层的形成情况。结果三种方法对根管清理能力差异无统计学意义(P>0.05)而无论使用何种预备方法,其对根中1/3及根冠1/3处的清理能力优于根尖1/3部,两者差异有统计学意义(P<0.05)。3种方法根管预备时间分别为:逐步后退法(12.8±1.26)min,逐步深入法(9.02±0.74)min,被动逐步后退法(超声与手用器械联合应用法)(12.21±1.90)min,三组差异无统计学意义(P>0.05)。结论三种根管预备方法均不能达到完全的根管清理,尤其是对于根尖1/3部,清洁效果很不理想;总体上看,根中及根冠1/3清洁度显著优于根尖1/3。被动逐步后退法(超声与手用器械联合应用)及逐步后退法操作均较费时、费力,而逐步后退法根管预备时间略短于另两种方法且较省力。
Objective The aim of this study was to compare the effectiveness of three instrumentation techniques in preparation of the fine curved canals of posterior teeth. Methods Fortyfive mesiobuccal root canals in fleshly extracted human molar teeth were instrumented by using the stepback technique, the step-down technique or the passive step-back technique. Time of preparation of each canal was taken down. After cracking the roots longitudinally, the canal walls were observed under a scanning electron microscope, and the coronal, middle and apical thirds of each canal were photographed at the 100 and 1000 times magnification. Each canal was qualitatively evaluated and the groups were compared for the removal of debris and smear layer, both overall and at each level （apical, middle, and coronal）. Results There were no statistically significant differences between the techniques either overall or within any of the regions （P 〉 0.05）. When comoparing regions（regardless of technique）, the apical portion of the canal was less clean than the middle or coronal portions （P 〈 0.05）. Preparation time in these three techniques showed no statistical significance （P 〉 0.05 ）. Conclusions Efficacy differed little among the techniques.None of the three techniques removed smear layer completely and all left debris, especially within the apical third of the canals. The passive step-back technique was superior to the step-back and the step-down techniques when it was related to the cleaning efficiency, but it took a longer time for preparation and was so exhausting. The step-back technique can be used more easily within a short time.
出处
《中华口腔医学研究杂志（电子版）》
CAS
2008年第5期35-39,共5页
Chinese Journal of Stomatological Research(Electronic Edition)
关键词
根管预备
逐步后退法
逐步深入法
被动逐步后退法
细弯根管
Root canal preparation
Step-back technique
Step-down technique
Passive step-back technique
Fine curved canal
