3种机用单支锉镍钛系统对弯曲根管中心定位能力的比较

Comparison of the central positioning ability of three single-file nickel-titanium instruments in simulated curved root canals

目的·比较3种机用单支锉镍钛器械系统VDW Reciproc Blue(简称Blue)、FKG XP-endo shaper(简称XP)及M3-L platinum(简称M3)在预备弯曲根管时维持根管原有弯曲度的能力(即中心定位能力)。方法·选择30个树脂模拟弯曲单根管,随机分为3组(Blue组、XP组和M3组),分别用Blue、XP和M3进行根管预备。预备前后的根管内分别注入红色、蓝黑色墨水并在口腔科手术显微镜下拍摄照片。将预备前后的照片进行重叠,以预备前的根尖为圆心,半径从1 mm开始,每增加1 mm做一同心圆,依次递增至10 mm,使其与重叠图像相交成10条弧线,即10个测量位点,记录根管内外侧10个测量位点的去除量差值的绝对值,对3组之间的差异进行统计分析。预备根管后,用口腔科手术显微镜观察锉体有无拉伸形变。结果·M3组与Blue组之间、M3组与XP组之间根管内外侧去除量差值的绝对值的差异均有统计学意义(P=0.0031,P=0.0020),Blue组和XP组之间根管内外侧去除量差值的绝对值的差异无统计学意义(P=0.3502)。XP组锉体在口腔科手术显微镜下观察到出现解螺旋形变,放置于热水内未恢复原形态,M3组与Blue组锉体未观察到有形变。结论·3种单支镍钛锉对弯曲根管进行预备时均能良好地维持根管原有弯曲度,但Blue和XP较M3有更好地维持弯曲根管原始走向的能力。XP在预备树脂根管时容易出现器械形变,临床上应适当减少XP的使用次数。

Objective·To compare the ability of VDW Reciproc Blue(Blue),FKG XP-endo shaper(XP)and M3-L platinum(M3)instruments to maintain the original curvature of root canal(i.e.central positioning ability)in preparing curved root canals.Methods·Thirty resin-simulated curved single root canals were randomly divided into three groups.Root canal preparation was performed with a Blue file,an XP file or an M3 file randomly.Red or blue-black ink was injected into the root canal before and after preparation and photographs were taken under the stomatology surgical microscope.The images before and after preparation were overlapped.The apex of the prepared root was set as a circle center and the radius started at 1 mm.A concentric circle was made every 1 mm increased and sequentially incremented to 10 mm so that it intersected the image to form 10 measurement sites,and then the removal of ten measurement sites on the inside and outside of the root canal was recorded for statistical analysis.After the root canal was prepared the file was observed for tensile deformation under the stomatology surgical microscope.Results·There was significant difference in the absolute value of the difference between the internal and external removal of root canal between the M3 group and the Blue group,as well as the M3 group and the XP group(P=0.0031,P=0.0020);but there was no significant difference between the Blue group and the XP group(P=0.350).The file body of XP group was observed to have de-helix deformation under the stomatology surgical microscope,which did not return to its original shape when placed in hot water,and no deformation was observed in the file body of M3 group and Blue group.Conclusion·The three kinds of single-file nickel-titanium instruments have good formation ability when preparing the curved root canals.But XP file and Blue file can maintain the original curvature of root canals better than M3 file.XP files are prone to deformation when preparing resin root canal,therefore the use of XP should be appropriately reduced clinically.