Yadav Hemant Kumar, Yadav Rakesh Kumar, Chandra Anil, Tikku Aseem Prakash
Senior Resident, Division of Conservative Dentistry and Endodontics, Centre for Dental Education and Research, All India Institute of Medical Sciences, New Delhi, India.
Additional Professor , Dept. of Conservative Dentistry and Endodontics, Faculty of Dental Sciences, King George's Medical University, Lucknow, Uttar Pradesh, India.
J Dent (Shiraz). 2017 Jun;18(2):118-126.
Root canal therapy should not simply be the extirpation of the pulp and widening of the canal. But one should also focus on how to completely remove the loosely-attached smear layer because it has adverse effects on the final outcome of the treatment.
This study compared the efficacy of Etidronic acid, SmearClear and MTAD to remove the smear layer created during instrumentation in different regions of the root canal.
Fifty single-rooted mandibular premolars were decoronated from the cementoenamel junction and instrumented using the ProTaper universal rotary file system along with copious irrigation by 1.0% sodium hypochlorite and distilled water. On the basis of the type of chelating agent used for irrigation, samples (n=10) were then randomized into five groups as: Group I- 9% etidronic acid, Group II- 18% etidronic acid, Group III- SmearClear, Group IV- MTAD and Group V- normal saline. Subsequent to irrigation, all samples were rinsed, dried and sectioned longitudinally for evaluation of the smear layer removal under scanning electron microscope (2000X). Data were statistically analyzed by two-way analysis of variance and Tukey's post hoc test with statistical significance set at < 0.5.
The result showed that SmearClear was the most efficient in removing the smear layer. However, etidronic acid was found inferior than both SmearClear and MTAD.
Chelators are essential for complete smear layer removal in association with organic solvent.
根管治疗不应仅仅是牙髓摘除和根管扩宽。还应关注如何彻底清除松散附着的玷污层，因为它会对治疗的最终结果产生不利影响。
本研究比较了依替膦酸、SmearClear和MTAD去除根管不同区域预备过程中形成的玷污层的效果。
从50颗单根下颌前磨牙的牙骨质牙釉质界处截冠，使用ProTaper通用旋转锉系统进行预备，并同时用1.0%次氯酸钠和蒸馏水大量冲洗。根据冲洗时使用的螯合剂类型，将样本（n = 10）随机分为五组：第一组 - 9%依替膦酸，第二组 - 18%依替膦酸，第三组 - SmearClear，第四组 - MTAD，第五组 - 生理盐水。冲洗后，所有样本均冲洗、干燥并纵向切片，以便在扫描电子显微镜（2000倍）下评估玷污层的去除情况。数据采用双向方差分析和Tukey事后检验进行统计学分析，设定统计学显著性水平为<0.5。
结果显示SmearClear在去除玷污层方面效率最高。然而，发现依替膦酸不如SmearClear和MTAD。
螯合剂对于与有机溶剂联合彻底去除玷污层至关重要。
