Departments of Endodontic, Faculty of Dental Medicine for Girls, Al-Azhar University, Cairo, Egypt.
Faculty of Dentistry, British University in Egypt, Cairo, Egypt.
J Indian Soc Pedod Prev Dent. 2023 Apr-Jun;41(2):170-177. doi: 10.4103/jisppd.jisppd_89_23.
This study evaluated the effect of using chitosan, nano-chitosan, and ethylenediaminetetraacetic acid (EDTA) as final irrigating solutions on smear layer cleanliness and Ca/P ratio of dentin.
Forty-eight decoronated human single-rooted teeth were used. They were divided randomly into four groups (n = 12) based on the final irrigating solution used as follows: (a) control group (IA; n = 6) normal saline, (IB; n = 6) were left unprepared; group II - 0.2% chitosan; group III - 0.2% nano-chitosan; and group IV - 17% EDTA. Samples were prepared using ProTaper Next and irrigated with 2.6% NaOCl 5 ml after each instrument using 31-gauge needle. Final rinse was used 5 ml/3 min according to the assigned group. The specimens were prepared for evaluation.
Best smear layer removal was observed in group IV. No statistically significant differences (P > 0.05) were observed between the experimental groups (II, III, and IV) coronally; however, a statistically significant difference (P < 0.05) was observed between groups II and IV at middle and apical thirds. Intragroup comparison showed that apical third exhibited the highest mean smear layer score among all experimental groups. The highest mean Ca/P ratio was in the 0.2% nano-chitosan group, while the highest calcium loss was in the 17% EDTA group.
17% EDTA is a potent chelating agent that can successfully remove the smear layer but compromises the Ca/p ratio of dentin. However, 0.2% chitosan and its nanoparticles have comparable chelating effects and induce remineralization of the root canal dentin.
本研究评估了使用壳聚糖、纳米壳聚糖和乙二胺四乙酸（EDTA）作为最终冲洗液对玷污层清洁度和牙本质 Ca/P 比值的影响。
将 48 颗去冠的人单根恒牙随机分为 4 组（n = 12），根据最终冲洗液的不同分组如下：（a）对照组（IA；n = 6）生理盐水，（IB；n = 6）未预处理；组 II-0.2%壳聚糖；组 III-0.2%纳米壳聚糖；组 IV-17%EDTA。使用 ProTaper Next 预备样本，并在每次使用 31 号针头的 2.6% NaOCl 5ml 后用 31 号针头冲洗。根据分组使用 5ml/3min 进行最终冲洗。制备标本进行评估。
组 IV 的玷污层去除效果最佳。实验各组（II、III 和 IV）冠部之间无统计学差异（P > 0.05）；然而，中、根尖部之间组 II 和 IV 之间存在统计学差异（P < 0.05）。组内比较显示，所有实验组中，根尖部的玷污层评分最高。0.2%纳米壳聚糖组的 Ca/P 比值最高，而 17%EDTA 组的钙损失最高。
17%EDTA 是一种有效的螯合剂，可成功去除玷污层，但会损害牙本质的 Ca/P 比值。然而，0.2%壳聚糖及其纳米颗粒具有相似的螯合作用，并诱导根管牙本质的再矿化。
