目的: 观察根管预备中在相同冲洗液的条件下不同超声冲洗方法对根管玷污层的清除效果。方法:
收集因正畸拔除单根管前磨牙48 颗，均采用M3 镍钛机用锉进行根管预备后随机分成4 组。A 组超声波连续冲
洗60s; B 组超声波冲洗20s，停10s 后不更换冲洗液继续冲洗( 分3 次进行) ; C 组超声冲洗20s，再用2mL 1%次
氯酸钠( NaClO) 冲洗根管( 分3 次进行) ; D 组( 对照组) 0．9%生理盐水( NaCl) 注射器冲洗60s。最后将牙体沿颊
舌向纵劈，扫描电镜观察各组样本在根颈、中、尖1 /3 玷污层的清除情况，根据评分统计分析比较各组根管清洁
效果。结果: 扫描电镜结果: C 组对玷污层的清除能力最强，且对根尖1 /3 的玷污层能起到一定的清洁作用; 统
计学结果: C 组牙本质小管开口在根尖1 /3 和根中1 /3 的数量明显多于A、B、D 组( P＜0．05) ，而A、B、C 三组根颈
处之间差异不明显( P＞0．05) 。结论: 通过扫描电镜的观察，玷污层通过超声间断冲洗伴随更换冲洗液的清洁效
果要好于超声连续冲洗后的效果。

Objective: To observe the elimination effect of different ultrasonic irrigation methods on
root canal smear layer in root canal preparation．Methods: Collected 48 premolars of single tube from
orthodontic extraction were randomLy divided into 4 groups after root canal preparation with M3 nickeltitanium
files． Group A of ultrasonic continuous irrigation 60 s; group B of ultrasonic continuous
irrigation 20 s，and then keep irrigating with the same fluid after 10 s pause( 3 times) ; group C of ultrasonic
continuous irrigation 20 s，and then keep irrigating with 2mL 1%NaClO 10 s( 3 times) ; group D
( control group) of syringe flush 60 s with 0．9%NaCl．Finally， the teeth were split along the buccal －
tongue，observed in elimination of smear layer among the cap，medial and apex area of root in 1 /3 by
scanning electron microscope， then to compare the root canal cleaning effect of each group according to
the score statistical analysis．Results: SEM results: group C of ability to purge the smear layer is the
strongest，and can play a role in cleaning the smear layer of root apex area 1 /3; Statistical results:
Group C the opening of dentin tubules in the medial and apex area of root 1 /3 is significantly more than
the number of group A，B and D( P＜0．05) ， the opening of dentin tubules of root cap with no significant
difference among the group A，B and C( P＞0．05) ．Conclusion: Through SEM observation， the cleaning
effect with smear layer to ultrasonic irrigate root canals at intervals with replacement irrigants is better
than irrigate continuously washing．

R781

 收稿日期: 2017－03－15; 修回日期: 2017－08－24
基金项目: 内蒙古自治区人民医院院内基金( 2016070)
作者简介: 王宾( 1982) ，男，内蒙古自治区人民医院口腔科主治医师。
通讯作者: 陈丽春，主任医师，硕士研究生导师，E－mail: chenlichun123@ 126． com 内蒙古自治区人民医院口腔科，
010017