Sahebi Safoora, Asheghi Bahar, Samadi Yasser, Eskandari Fateme
Department of Endodontics, Dental school, Shiraz University of Medical Sciences, Shiraz, Iran.
Iran Endod J. 2022 Winter;17(1):13-19. doi: 10.22037/iej.v17i1.36566.
The goal of this paper was to determine the impact of calcium hydroxide (CH) and nano-calcium hydroxide (NCH) on the push-out bond strength of an epoxy resin-based sealer.
A total of 48 mandibular premolars were decoronated and instrumented by a ProTaper rotary system up to F4. The specimens then were randomly allocated into 3 groups (=16). The two intervention groups were treated with either CH or NCH and one control group which did not receive any intracanal medicament. After one week of medicament placement, the specimens were irrigated by 10 mL 17% EDTA, followed by 10 mL 2.5% NaOCl and an ultimate flushing by 5 mL sterile saline. The samples were obturated using AH-Plus Jet sealer and gutta-percha by lateral condensation technique. Push-out test was done by a universal test machine to evaluate the bond strength among the sealer and the root canal dentin. Repeated measurement analysis followed by Tukey's HSD and Bonferroni post-hoc tests were used for data analysis.
The control group showed a higher push-out bond strength in comparison to the specimens in the CH and NCH groups (<0.05). In spite of the greater push-out bond strength of the samples treated with NCH in comparison to those in CH group, no statistically notable difference was found among them (>0.05). Additionally, irrespective of the kind of medicament, the bonding at the apical level of the root canal was stronger compared to the coronal third (<0.001).
According to the present study, application of CH and NCH resulted in a significant reduction of the bond strength between the epoxy resin-based sealer and dentinal walls. Although, application of these medicaments resulted in reduction of bonding of epoxy resin-based sealers root canal dentin significantly.
本文的目的是确定氢氧化钙（CH）和纳米氢氧化钙（NCH）对环氧树脂类封闭剂推出粘结强度的影响。
选取48颗下颌前磨牙，截冠后用ProTaper旋转系统预备至F4。然后将标本随机分为3组（每组16个）。两个干预组分别用CH或NCH处理，一个对照组不接受任何根管内药物治疗。药物放置一周后，标本先用10 mL 17%乙二胺四乙酸（EDTA）冲洗，再用10 mL 2.5%次氯酸钠（NaOCl）冲洗，最后用5 mL无菌生理盐水彻底冲洗。样本采用AH-Plus Jet封闭剂和牙胶通过侧向加压技术进行充填。通过万能试验机进行推出试验，以评估封闭剂与根管牙本质之间的粘结强度。数据分析采用重复测量分析，随后进行Tukey's HSD检验和Bonferroni事后检验。
与CH组和NCH组的标本相比，对照组显示出更高的推出粘结强度（P<0.05）。尽管NCH处理的样本比CH组的样本具有更大的推出粘结强度，但两组之间没有统计学上的显著差异（P>0.05）。此外，无论使用何种药物，根管根尖部的粘结都比冠部三分之一处更强（P<0.001）。
根据本研究，CH和NCH的应用导致环氧树脂类封闭剂与牙本质壁之间的粘结强度显著降低。尽管如此，这些药物的应用确实显著降低了环氧树脂类封闭剂与根管牙本质的粘结。
