Dental caries is the most common oral disease and the most common cause of resin restorations. In minimally invasive dentistry, the principle behind cavity preparation is to remove external caries-infected dentin (CID) and preserve internal caries-affected dentin (CAD) and sound dentin (SD). The cavity floor is mainly composed of CAD, but the poor bonding performance of CAD has become a widespread concern. This study evaluated the performance of a new collagen-reactive monomer (ITCM) used as a primer to improve the bonding performance of CAD. The experimental specimens were grouped as follows: SD, CAD, and ITCM-pretreated CAD (CAD-ITCM). Dentin slices were obtained for attenuated total reflectance-Fourier transform infrared (ATR-FTIR) analysis. The bonded samples were subjected to microtensile bond strength analysis after 24 h of water storage or aging by thermocycling, and the bonding interface quality was evaluated by nanoleakage assessment, interfacial nanoindentation testing, and in situ zymography. Cytotoxicity experiments with ITCM were performed. ATR-FTIR showed that the isocyanate groups in ITCM can covalently bind and form hydrogen bonds with the collagen in CAD to mediate chemical bonding. ITCM pretreatment significantly improved the bond strength of CAD (P < 0.05), reduced interfacial nanoleakage, improved the sealing of the bonding interface, enhanced the homogeneity of the hybrid layer, and inhibited matrix metalloproteinase activity. In addition, ITCM presented acceptable biocompatibility for dental restorative application. Taken together, this study reported the application of ITCM to induce collagen-based chemical bonding in the CAD bonding system, which fills the gap in strategies to improve the bonding performance of CAD immediately and after aging and has important clinical application prospects.

中文翻译：

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使用异氰酸酯底漆增强与受龋齿影响的牙本质的粘合。


龋齿是最常见的口腔疾病，也是树脂修复最常见的原因。在微创牙科中，窝洞预备的原理是去除外部龋齿感染的牙本质（CID）并保留内部龋齿影响的牙本质（CAD）和健全的牙本质（SD）。空腔底板主要由CAD构成，但CAD的粘结性能差已成为人们普遍关注的问题。本研究评估了一种新型胶原反应单体 (ITCM) 用作底漆以提高 CAD 粘合性能的性能。实验样本分组如下：SD、CAD 和 ITCM 预处理的 CAD (CAD-ITCM)。获得牙本质切片用于衰减全反射傅里叶变换红外（ATR-FTIR）分析。粘合样品在水储存或热循环老化24小时后进行微拉伸粘合强度分析，并通过纳米渗漏评估、界面纳米压痕测试和原位酶谱法评估粘合界面质量。用 ITCM 进行细胞毒性实验。 ATR-FTIR 显示 ITCM 中的异氰酸酯基团可以与 CAD 中的胶原蛋白共价结合并形成氢键，从而介导化学键合。 ITCM预处理显着提高了CAD的粘结强度（P < 0.05），减少了界面纳米渗漏，改善了粘结界面的密封性，增强了杂化层的均匀性，并抑制了基质金属蛋白酶活性。此外，ITCM 还为牙科修复应用提供了可接受的生物相容性。 综上所述，本研究报道了ITCM在CAD粘合系统中诱导基于胶原蛋白的化学粘合的应用，填补了改善CAD立即和老化后粘合性能策略的空白，具有重要的临床应用前景。