两种根管封闭剂GuttaFlow 2和AH Plus与根管壁间粘接性能比较

A study to compare the difference of bond strength between GuttaFlow 2 and AH Plus

目的比较两种根管封闭剂GuttaFlow 2及AH Plus与根管壁的粘接性能,为临床应用提供参考。方法选取新鲜拔除的单根管下颌前磨牙20颗,根据所用封闭剂不同随机分为两组,即AH Plus实验组及GuttaFlow 2实验组,每组10颗离体牙。两组均使用旋转镍钛器械ProTaper预备至F3,单尖法充填后,自冠方向根方每间隔0.25mm制作硬组织切片8片,切片厚度1mm,应用万能实验机进行推出实验,比较两组间推出强度(MPa),并在立体显微镜下观察断裂类型。结果每组封闭剂组内不同牙根水平推出强度无统计学差异(P>0.05),在两封闭剂实验组间,AH Plus实验组试样的平均推出强度(1.58±0.95MPa)明显高于GuttaFlow 2实验组(0.38±0.28MPa)(P<0.001)。两实验组均以混合型断裂(mixed)为主要断裂类型,但GuttaFlow 2实验组中有16.4%的断裂为管壁间断裂(adhesive),而AH Plus实验组中并未观察到此种断裂类型。结论在实验条件下,GuttaFlow 2组的推出强度明显低于AH Plus组,有16.4%的断裂为管壁间断裂。

Objective To compare the push-out bond strength of two kinds of sealer GuttaFlow 2 and AH Plus between sealer and root canal dentin. Methods Twenty extracted mandibular premolars with single canal were randomly divided into two groups GuttaFlow 2 and AH Plus, ten teeth in each group. The canals were prepared by Pro Taper system to F3 and obturated by GuttaFlow or AH Plus using single-cone technique. Each root was sectioned into eight slices with1.0-mm-thick, and bond strengths were measured using a universal testing machine. The mode of failure was determined by visual inspection under magnification（×20）. Results The bond strength of group GuttaFlow 2 was significant lower than that of group AH Plus（P〈0.001）. However, no significant difference on bond strength was detected in different root segment location in either group. Mixed mode of failure was predominately in both groups. There was 16.4% samples in group GuttaFlow 2 with adhesive mode of failure,but no adhesive failure was found in group AH Plus. Conclusion The bond strength of GuttaFlow 2 was significant lower than AH Plus.