超声法取根管内折断器械对根管壁损伤的体外研究  

Evaluation of injury on root canal during removing broken instruments by ultrasonic technique

作　　者：张志苓[1] 付梅[2] 侯本祥[2] 

机构地区：[1]首都医科大学附属北京儿童医院口腔科,100045 [2]首都医科大学口腔医学院牙体牙髓科

出　　处：《北京口腔医学》2010年第1期33-35,共3页Beijing Journal of Stomatology

基　　金：国家自然科学基金(30872877);首都医学发展科研基金(2005-3046)

摘　　要：目的比较不同弯曲度根管用显微超声技术取折断器械时对根管壁的损伤程度。方法体外建立不同弯曲度根管内根尖1/3器械折断模型30例,手术显微镜辅助下超声法取根管内折断器械,通过图像分析软件对术前、术后根管横截面积的变化进行分析比较。结果根管内折断器械取出后的横截面积变化经过多因素方差分析,直根或轻度弯曲组与中度弯曲组根管横截面积增加值的差别无统计学意义(P>0.05);重度弯曲组与直根或轻度弯曲组、中度弯曲组之间根管横截面积的增加值差别具有显著性意义(P<0.05);重度弯曲组与轻度弯曲组和中度弯曲组间的差别主要在4、6mm的位置,在2mm和8mm处的差别无统计学意义(P>0.05)。结论用超声法取位于重度弯曲根管内根尖1/3的折断器械时,对根管壁损伤较大,损伤最大部位为根管中部,易造成此处侧穿,故位于重度弯曲根管根尖1/3的折断器械不建议用超声法取出。Objective To evaluate the injury on root canal during removing broken instruments by ultrasonic technique. Methods To build research models with broken instruments located in the apical 1/3 part of the root of 30 extracted teeth were established in vitro. The ultrasonic technique with the aid of dental operating microscope was employed to remove the broken instruments. The roots were sectioned after operation and the cross section area of the root was measured and evaluated. Results The difference of injury to the root canal wall among the roots with curved angle of over 25 degree, under 25 degree or straight ones was significant （p 〈 0. 05 ）. The most remarkable injury on the wall was seen in the curved root over 25 degree, and at the sections of 4ram and 6 mm from apex. Conclusion Removal of a fractured file fragment from the apical third of curved canals should not be routinely attempted.

关 键 词：超声技术 牙科手术显微镜 器械折断 根管侧穿 

分 类 号：R781.05[医药卫生—口腔医学]