EDTA凝胶与溶液对根管壁结构影响的比较研究

目的 研究EDTA凝胶与EDTA溶液在不同作用时间下,对根管玷污层及根管壁结构的影响.方法 采用因正畸需要新鲜拔除的健康上颌恒前磨牙7颗,常规根管预备后,取根中1/3段沿牙体长轴剖开,每根管分为两部分,每颗牙的两根管共获得4个标本,取其中1颗牙的4个标本作为对照组,其余每颗牙的4个标本分别纳入4个实验组.A组:15% EDTA水溶液冲洗1 min;B组: 15?TA水溶液冲洗5 min;C组:格兰凝胶涂布1 min;D组:格兰凝胶涂布5 min.扫描电镜观察各组根管内玷污层情况及牙本质结构的变化.结果 15?TA水溶液处理1 min即可有效去除根管玷污层,处理5 min则会引起管周和管间牙本质轻微脱矿;格兰根管凝胶处理1 min和5 min均能有效去除根管内玷污层,但均会引起牙本质过度脱矿和腐蚀.结论 格兰根管凝胶和EDTA水溶液均可去除根管玷污层,但持续作用于根管壁的时间不应超过1 min,以避免管壁过度脱矿.

Different Effects of EDTA Gel and EDTA Solution on Dentin structure of Root Canal

Objective To evaluate the effects of EDTA solution and EDTA gel on smear layer removal and dentine structure of root canal.Methods Healthy human premolars with two roots were extracted for orthodontics purpose and used in the experiment.After root canal preparation,middle third of each root were cut longitudinally into two equal segments.Every tooth was divided into 4 slices and designed into 4 groups separately.Group A: irrigated with 15% EDTA solution for 1 min;Group B: irrigated with 15% EDTA solution for 5 min;Group C: treated with GlydeTM File Prep for 1 min;Group D: treated with GlydeTM File Prep for 5 min.All samples were observed with scanning electron microscopy.Results It was showed that 1 min EDTA irrigation was effective for removing the smear layer,while 5-min application caused dentin erosion.Both 1 min and 5-min application of GlydeTM File Prep caused excessive dentin demineralization.Conclusion EDTA solution and GlydeTM File Prep can significantly remove the smear layer,but the procedure should be limited in less than 1 min during endodontic treatment.