3种镍钛机用根管预备器械抗扭力性能的比较  

Torque resistance of three different types of nickel-titanium rotary instruments

作　　者：孙炜 侯本祥[2] 

机构地区：[1]湖南省长沙市口腔医院修复科,湖南长沙410005 [2]首都医科大学附属北京口腔医院牙体牙髓病科,北京100050

出　　处：《华西口腔医学杂志》2010年第5期471-474,共4页West China Journal of Stomatology

基　　金：首都医学发展科研基金资助项目(2005-3046)

摘　　要：目的比较3种镍钛机用根管预备器械ProTaper、Hero642、Mtwo扭转折断的差异。方法通过建立体外模型,比较3种镍钛锉在尖端被束缚时发生扭转折断的时间差异,并通过扫描电镜观察3种器械的断端横截面形态。结果 3种镍钛根管锉抗扭力性能有所不同。Mtwo的折断时间长于ProTaper和Hero642的折断时间,差异有统计学意义,而ProTaper和Hero642的折断时间无显著性差异。3种器械横截面设计不同,折断面可见大量韧窝,折断方式基本上为塑性断裂。器械的内部质量缺陷降低其抗疲劳能力。结论 Mtwo在抗扭力性能上优于ProTaper和Hero642,横截面的不同设计影响了器械的抗扭力性能,器械质量缺陷会影响器械的抗疲劳性能,使器械易于折断。Objective To compare torsional fracture of three different types of nickel-titanium rotary instruments ProTaper,Hero642 and Mtwo by making a stimulate models in vitro.Methods Through the establishment of model in vitro,compared the different time with 3 kinds of nickel titanium file in cutting-edge bound occurs,and to observe the section of fractured instruments by scanning electron microscope.Results The resistence to torque was different from three types of nickel titanium instruments.The time to fracture of Mtwo was significantly longer than ProTaper’s and Hero642’s,but ProTaper’s and Hero642’s had no significant difference.Three kinds cross-sectional design were different,a lot of toughness nests were seen in broken surface.Most of them were ductile fracture.Time to fracture was influenced by the quality disfigurement.Conclusion The resistance to torque of Mtwo was better than ProTaper and Hero642.The lifespan was influenced by the design of cross-section.The quality disfigurement of the files reduced the resistance to flexual fatigue.

关 键 词：镍钛机用根管锉 扭转折断 横截面 

分 类 号：R781.05[医药卫生—口腔医学]