Stomatology Hospital, School of Stomatology, Zhejiang University School of Medicine, Clinical Research Center for Oral Diseases of Zhejiang Province, Key Laboratory of Oral Biomedical Research of Zhejiang Province, Cancer Center of Zhejiang University, Hangzhou, China.
College of Sericulture, Textile and Biomass Sciences, Southwest University, Chongqing, China.
J Mech Behav Biomed Mater. 2022 Feb;126:105038. doi: 10.1016/j.jmbbm.2021.105038. Epub 2021 Dec 11.
This study aimed to evaluate the potential of the extrafibrillar dentin demineralization strategy on the long-term dentin bond strength of an etch-and-rinse adhesive.
A water-soluble glycol chitosan-EDTA (GCE), a chelating conditioner, was synthesized and subjected to size-exclusion dialysis to obtain molecules >40 kDa. The conjugation of EDTA to glycol chitosan was analyzed by Fourier transform infrared (FTIR) spectroscopy. Mid-coronal dentin surfaces of 80 teeth were either acid-etched with 35% phosphoric acid or conditioned with 25 mg/mL GCE (n = 40) and thoroughly water-sprayed before applying the etch-and-rinse adhesive Adper Single Bond Plus and placing Z250 composite resin (3 M Oral Care; St Paul, MN, USA). Resin-bonded specimens were prepared into beams with a cross-sectional area of about 0.9 mm vertically through the resin-dentin interfaces before the microtensile bond strengths (MTBS) were determined immediately or after 3, 6, or 12 months of water storage. The resin-dentin interfaces were analyzed using transmission electron microscopy (TEM). The MTBS data were analyzed using two-way ANOVA followed by the LSD post-hoc multiple comparisons (P < 0.05).
FTIR spectra showed that EDTA was successfully conjugated to glycol chitosan. The phosphoric acid-etching group and GCE-conditioning group showed similar bond strength values after 24 h of water storage. The bond strength of the phosphoric acid-etching group after 12-month water aging was significantly reduced from 51.61 ± 3.30 MPa to 38.57 ± 4.81 MPa, while the bond strength of the GCE-conditioning group was not significantly reduced from 50.28 ± 3.62 MPa to 46.40 ± 4.71 MPa.The degradation of the hybrid layer could be detected in the phosphoric acid-etching group after 12 months of water aging, but not in the GCE-conditioning group.
The extrafibrillar dentin demineralization strategy using GCE conditioner could defy the hybrid layer degradation of the dentin bond after 12 months of water aging and enhance the dentin bond durability of the etch-and-rinse adhesive Adper Single Bond Plus.
本研究旨在评估在纤维外脱矿策略下，对一种自酸蚀粘结剂长期牙本质粘结强度的影响。
合成了一种水溶性的壳聚糖-EDTA（GCE），一种螯合处理剂，并通过尺寸排阻透析获得大于 40 kDa 的分子。傅里叶变换红外（FTIR）光谱分析 EDTA 与壳聚糖的结合。80 颗牙齿的中部牙本质表面用 35%磷酸酸蚀或用 25 mg/mL GCE 处理（n = 40），然后彻底水喷，再应用自酸蚀粘结剂 Adper Single Bond Plus 和放置 Z250 复合树脂（3M 口腔护理；明尼苏达州圣保罗）。将制备好的试件从树脂-牙本质界面处垂直于横截面约 0.9mm 处切割成梁，然后立即或在 3、6 或 12 个月水储存后测定微拉伸粘结强度（MTBS）。使用透射电子显微镜（TEM）分析树脂-牙本质界面。使用双向方差分析（ANOVA）和 LSD 事后多重比较（P < 0.05）分析 MTBS 数据。
FTIR 图谱显示 EDTA 成功地与壳聚糖结合。在 24 小时水储存后，磷酸酸蚀组和 GCE 处理组的粘结强度值相似。磷酸酸蚀组在 12 个月水老化后的粘结强度从 51.61 ± 3.30 MPa 显著降低至 38.57 ± 4.81 MPa，而 GCE 处理组的粘结强度从 50.28 ± 3.62 MPa 至 46.40 ± 4.71 MPa 无明显降低。在 12 个月水老化后，磷酸酸蚀组的混合层可见降解，但 GCE 处理组未见降解。
使用 GCE 处理剂的纤维外脱矿策略可在 12 个月水老化后抵抗牙本质粘结的混合层降解，增强自酸蚀粘结剂 Adper Single Bond Plus 的牙本质粘结耐久性。
