6种冲洗剂组合对桩道内壁超微结构的影响

Impact of six different irrigations on ultra-structure of post space

目的:比较6种冲洗剂组合去除桩道内壁玷污层的能力,为临床应用提供理论参考依据。方法:收集30颗新鲜无龋的人单根管离体前磨牙,按常规方法桩道预备后随机分为6组,采用6种处理方式对桩道进行处理。Ⅰ组:生理盐水组(对照组);Ⅱ组:3%过氧化氢溶液,5.25%次氯酸钠溶液;Ⅲ组:2%洗必泰溶液,5.25%次氯酸钠溶液;Ⅳ组:3%过氧化氢溶液,17%EDTA溶液;Ⅴ组:2%洗必泰溶液,17%EDTA溶液;Ⅵ组:5.25%次氯酸钠溶液,17%EDTA溶液。每组冲洗剂组合处理后,生理盐水冲洗,在场发射环境扫描电镜(FE-SEM)下观察不同方式处理后的根管内牙本质微观形态,并采用Berg分级法进行评价。结果:Ⅰ组(对照组)的桩道内壁可见大量典型的玷污层,牙本质小管完全消失。Ⅱ组和Ⅲ组均未有效去除玷污层,牙本质小管口堵塞。Ⅳ组玷污层部分去除,碎屑较多。Ⅴ组、Ⅵ组处理方式均可以有效去除桩道预备后根管内壁形成的玷污层,并达到Ⅱ级甚至更好效果。尤其是次氯酸钠/EDTA组,达到Ⅰ级,残屑极少。结论:2%洗必泰/17%EDTA、5.25%次氯酸钠/17%EDTA2种冲洗剂组合均可有效去除桩道预备产生的玷污层,且冲洗的处理效果由桩道上部向下部逐渐减弱。

Objective：To evaluate the smear layer elimination capability effectiveness of six surface treatments after post space preparation.Methods：Thirty pulpless single-rooted teeth were divided into six groups on the basis of the irrigation regimen after post after post space preparation.（i）saline irrigation（control）;（ii）irrigation with 3% hydrogen peroxide followed by 5.25%sodium hypochlorite（NaOCl）;（iii）irrigation with 2% chlorhexidine solution followed by 5.25% sodium hypochlorite（NaOCl）;（iv）irrigation with 3% hydrogen peroxide followed by 17% EDTA solution.（v）irrigation with 2% chlorhexidine solution followed by 17%EDTA solution;（vi）irrigation with 5.25% sodium hypochlorite（NaOCl）followed by 17%EDTA solution.All the groups were irrigated by 10 ml saline.After irrigation,roots were separated into 3 thirds and each third was observed by field emission scanning electron microscopy（FE-SEM）at a 2 000× magnification.The effectiveness was evaluated by Berg classification.Results：There was a large number of typical smear layer on post space in Group 1（control）.Group 2 and Group 3 didn＇t got rid of the smear layer effectively.Part of the smear layer was eliminated in Group 4.Group 5 and Group 6 did not eliminate the smear effectively.Group 6 seemed to be the most effective in eliminating the smear from canal walls.Conclusion：Irrigation with 2%chlorhexidine solution followed by 17%EDTA solution and 5.25% sodium hypochlorite（NaOCl）followed by 17% EDTA solution can eliminate the smear effectively.Irrigation effect is different on different root levels.The cervical level is more effective than the apical level.