WaveOne与WaveOne Gold镍钛器械根管预备后牙根微裂的体外研究

Dentinal crack formation during root canal instrumentation by WaveOne and WaveOne Gold

目的:比较WaveOne与WaveOne Gold往复式镍钛旋转器械根管预备后牙根微裂的发生。方法:将30颗离体下颌切牙随机分成3组(n=10),实验组分别采用WaveOne和WaveOne Gold镍钛锉预备根管至P号,对照组则不进行根管预备。距根尖孔3 mm、6 mm和9 mm处进行水平切盘,体视显微镜下观察牙根不同横截面牙根微裂的发生情况。结果:对照组未观察到牙根微裂。实验组中,WaveOne和WaveOne Gold组产生牙根微裂的比例分别为90%和50%,两者之间差异有统计学意义(P<0.01)。所有实验组3 mm切面牙根微裂发生数目均最多。在3 mm、6 mm和9 mm各切面WaveOne组牙根微裂发生数目显著高于WaveOne Gold组(P<0.01)。结论:使用WaveOne Gold镍钛系统进行根管预备产生的牙根微裂明显低于WaveOne。

Objective:To compare the incidence of dentinal cracks after root canal instrumentation with WaveOne and WaveOne Gold NiTi rotary systems.Methods:Thirty extracted mandibular central incisors with mature apices and straight root canals(<5°)were selected and kept in saline.The root canals were instrumented by using WaveOne and WaveOne Gold systems.All roots were horizontally sectioned from the apex.The slices were then viewed through a stereomicroscope at ×25 magnification.The samples were photographed with a camera to determine the presence of dentinal cracks.Results:No cracks were observed in the control group.WaveOne Gold files(50%)showed significantly fewer microcracks than the WaveOne files(90%)(P<0.01).Both files caused cracks mainly at the 3 mm section.At 3 mm,6 mm and 9 mm sections,WaveOne files produced significantly more microcracks than the WaveOne Gold files respectively(P<0.01).Conclusion:WaveOne Gold files resulted in less dentinal cracks than WaveOne files.