被动超声冲洗对弯曲根管的碎屑清理能力和根管形态的影响

目的: 评价被动超声冲洗在弯曲根管内碎屑清理能力和根管偏移量。方法: 选取下颌磨牙近中弯曲根管36个,弯曲度在25°以上,以机用 XP-endo Shaper根管锉预备根管。根据弯曲长度（curved length,CL）和冲洗方式分为A1组（CL>3 mm,注射器冲洗）、B1组（CL>3 mm,超声K锉冲洗）、C1组（CL>3 mm,irrisafe超声锉冲洗）、A2组（CL<3 mm,注射器冲洗）、B2组（CL<3 mm,超声K锉冲洗）和C2组（CL<3 mm,irrisafe超声锉冲洗）,每组6个样本。对所有样本冲洗前、后进行Micro-CT扫描,计算冲洗后根管内体积增加量和根管偏移量。采用SPSS 22.0软件包对数据进行统计学分析。结果: 在CL>3 mm的根管根尖区,PUI+irrisafe组的根管体积增量显著高于PUI+K锉和注射器冲洗（P<0.05）,并且在距离根尖孔5 mm处PUI+irrisafe形成的根管偏移量显著低于PUI+K锉（P<0.05）;与注射器冲洗相比无显著差异（P>0.05）。在CL<3 mm的根管中,PUI+irrisafe组和PUI+K锉组的根管体积增量均显著高于注射器冲洗（P<0.05）,但根管偏移量与注射器冲洗无显著差异（P<0.05）。结论: 在弯曲长度较大的根管中,被动超声冲洗结合预弯锉可获得更好的清理效果;而在弯曲长度较小的根管中,被动超声冲洗结合K锉和预弯锉均安全有效。

Study on the influence of passive ultrasonic irrigation on debris cleaning ability and root canal shape

PURPOSE:To evaluate the safety and effectiveness of passive ultrasonic irrigation(PUI)in curved root canals,and debris cleaning ability and the amount of root canal transportation of passive ultrasonic irrigation(PUI)in curved root canals.METHODS:A total of 36 mesially curved root canals of mandibular molars with a curvature above 25°were selected.The root canals were prepared with XP-endo Shaper root canal file.The samples were divided into A1 group(curved length>3 mm,syringe irrigation),B1 group(curved length>3 mm,PUI+K file),C1 group(curved length>3 mm,PUI+irrisafe),A2 group(curved length<3 mm,syringe irrigation),B2 group(curved length<3 mm,PUI+K file),and C2 group(curved length<3 mm,PUI+irrisafe)(n=6).Micro-CT scans were performed on all samples before and after irrigation,and the volume increase in the root canal after irrigation and the transportation of the root canal were calculated.SPSS 22.0 software package was used to analyze the data.RESULTS:In the apical area of the root canal with a curved length greater than 3 mm,the root canal volume increase in the PUI+irrisafe group was significantly greater than that of the PUI+K file and syringe irrigation(P<0.05),and at 5 mm section,the transportation of the root canal formed by PUI+irrisafe was significantly lower than that of the PUI+K file(P<0.05),but there was no significant difference from syringe irrigation(P>0.05);in root canals with a curved length less than 3 mm,root canal volume increment of the file group was significantly greater than that of syringe irrigation(P<0.05),but there was no significant difference between the root canal transportation and syringe irrigation(P<0.05).CONCLUSIONS:In root canals with larger curved length,passive ultrasonic irrigation combined with a pre-curved file can obtain a better cleaning effect,while in root canals with smaller curved length,both K file and pre-curved file with passive ultrasonic irrigation are safe and effective.