Restorative and Dental Materials Department, Oral and Dental Research Institute, National Research Centre (NRC), Giza, Dokki, 12622, Egypt.
Biomaterials Department, Faculty of Dentistry, Cairo University, Cairo, 11553, Egypt.
BMC Oral Health. 2023 Apr 2;23(1):193. doi: 10.1186/s12903-023-02858-7.
The aim of this in vitro study was to evaluate push-out bond strength of different root-end filling materials using various irrigant solutions.
A push-out bond strength test was performed to evaluate the bond strength of two experimental root-end filling materials: namely, nano-hybrid mineral trioxide aggregate (MTA) and polymethyl methacrylate (PMMA) cement filled with 20% weight nano hydroxyapatite (nHA) fillers compared to conventional MTA. The irrigant solutions employed were sodium hypochlorite (NaOCl) in concentrations 1%, 2.5% and 5.25% and 2% chlorhexidine gluconate (CHX) followed by application of 17% ethylene diamine tetra-acetic acid (EDTA). A freshly extracted sixty single-rooted human maxillary central incisors were used. The crowns were removed, the canal apex was widened to simulate immature teeth. Each type of irrigation protocols was performed. After application and setting of the root-end filling materials, a slice of one mm thickness was cut transversely from the apical end of each root. Specimens were stored for 1 month in artificial saliva and were subjected to a push-out test to evaluate the shear bond strength. Data were analyzed using two-way ANOVA and Tukey test.
The experimental nano-hybrid MTA showed the highest significant push-out bond strength values when irrigated by NaOCl at several concentrations (1%, 2.5% and 5.25%) (P< 0.05). Meanwhile, irrigation with 2% CHX resulted in highest bond strength values in nano-hybrid white MTA (18 MPa) and PMMA filled with 20% weight nHA (17.4 MPa) with nonsignificant difference between them (p = 0.25). In each root-end filling material, irrigation with 2% CHX led to the highest significant bond strength, followed by NaOCl 1%, while the least significant bond strength was produced after irrigation with NaOCl 2.5% and 5.25% (P< 0.05).
Considering the limitations of this study, it may be concluded that the application of 2% CXH and 17% EDTA provides superior push-out bond strength to root canal dentin compared with irrigation with NaOCl irrigants and 17% EDTA, experimental nano-hybrid MTA root-end filling material provides enhanced shear bond strength than conventional micron-sized MTA root-end filling material.
本体外研究的目的是评估不同根管封闭材料在使用不同冲洗液时的推出粘结强度。
采用推出粘结强度试验评估两种实验性根管封闭材料的粘结强度：纳米复合矿物三氧化物聚合体（MTA）和聚甲基丙烯酸甲酯（PMMA）水泥填充 20%重量纳米羟基磷灰石（nHA）填料与传统 MTA 相比。所使用的冲洗液为浓度为 1%、2.5%和 5.25%的次氯酸钠（NaOCl）和 2%氯己定葡萄糖酸盐（CHX），随后应用 17%乙二胺四乙酸（EDTA）。使用 60 颗新鲜提取的上颌中切牙进行实验。去除牙冠，扩大根管根尖以模拟不成熟的牙齿。每种冲洗方案都进行了处理。在根管封闭材料应用和凝固后，从每个根的根尖端横切 1 毫米厚的切片。将标本在人工唾液中储存 1 个月，然后进行推出试验以评估剪切粘结强度。使用双向方差分析和 Tukey 检验对数据进行分析。
实验性纳米复合 MTA 在经不同浓度（1%、2.5%和 5.25%）次氯酸钠冲洗时显示出最高的显著推出粘结强度值（P<0.05）。同时，2% CHX 冲洗导致纳米复合白色 MTA（18MPa）和填充 20%重量 nHA 的 PMMA（17.4MPa）的粘结强度值最高，且两者之间无显著差异（p=0.25）。在每种根管封闭材料中，2% CHX 冲洗后粘结强度最高，其次是 1% NaOCl，而 2.5%和 5.25% NaOCl 冲洗后的粘结强度最低（P<0.05）。
考虑到本研究的局限性，可以得出结论，与次氯酸钠冲洗剂和 17% EDTA 相比，应用 2% CHX 和 17% EDTA 可提供优于根管牙本质的推出粘结强度，实验性纳米复合 MTA 根管封闭材料提供增强的剪切粘结强度比传统微米级 MTA 根管封闭材料。
