The water-rich nature of the dentin bonding microenvironment, coupled with the stresses on the bonding interface, contributes to the hydrolytic degradation of the hybrid layer, resulting in a decline in bonding durability and, ultimately, restoration failure. Currently, the 3-step etch-and-rinse technique remains the gold standard for dentin bonding, and the bonding mechanism mainly involves a physical interaction with little chemical bonding. In this study, we have developed a siloxane-modified polyurethane monomer (SPU) with acrylate and siloxane modifications that chemically binds to both collagen and hydroxyapatite in dentin. Formulated as a bisphenol A-glycidyl methacrylate alternative, the SPU monomer-based adhesive was designed to improve dentin bonding quality and durability. Attenuated total reflection Fourier transform infrared spectroscopy, thermogravimetric analysis, X-ray photoelectron spectroscopy, scanning electron microscopy, transmission electron microscope, and hydroxyproline release assays were performed on SPU-treated collagen, hydroxyapatite, and acid-etched dentin slices to dentin. The physicochemical properties of the configured SPU adhesives were profiled for polymerization behavior, water contact angle, and tensile strain and strength. The bonding effectiveness was assessed through micro-tensile strength, nano-leakage tests conducted on the bonded samples before and after thermal cycle aging. Finally, we further conducted in vivo and in vitro experiments to assess the biocompatibility of adhesives. The results showed that the siloxane groups of SPU monomer could covalently bind to dentin collagen and hydroxyapatite. The incorporation of SPU in the adhesive led to a significant increase in adhesive polymerization (P < 0.05) and tensile strain at break up to 134.11%. Furthermore, the SPU adhesive significantly improved dentin bond strength (P < 0.05), reduced interfacial nano-leakage (P < 0.05), and displayed good biocompatibility. In conclusion, the application of SPU, which achieves dual chemical bonding with dentin, can improve the quality of the hybrid layer, buffer the interfacial stresses, enhance the interfacial resistance to hydrolysis, and provide a feasible strategy to extend the service life of adhesive restorations.

中文翻译：

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能够与牙本质进行双重化学结合的新型单体，以提高结合耐久性。


牙本质粘合微环境的富含水分的性质，加上粘合界面上的应力，导致混合层的水解降解，导致粘合耐久性下降，最终导致修复失败。目前，三步蚀刻和冲洗技术仍然是牙本质粘合的黄金标准，粘合机制主要涉及物理相互作用，化学粘合很少。在这项研究中，我们开发了一种经过丙烯酸酯和硅氧烷改性的硅氧烷改性聚氨酯单体（SPU），它可以与牙本质中的胶原蛋白和羟基磷灰石进行化学结合。这种基于 SPU 单体的粘合剂是双酚 A-甲基丙烯酸缩水甘油酯的替代品，旨在提高牙本质粘合质量和耐用性。对 SPU 处理的胶原蛋白、羟基磷灰石和酸蚀牙本质切片对牙本质进行衰减全反射傅里叶变换红外光谱、热重分析、X 射线光电子能谱、扫描电子显微镜、透射电子显微镜和羟脯氨酸释放测定。配置的 SPU 粘合剂的物理化学特性包括聚合行为、水接触角、拉伸应变和强度。通过在热循环老化前后对粘合样品进行微拉伸强度、纳米泄漏测试来评估粘合效果。最后，我们进一步进行了体内和体外实验来评估粘合剂的生物相容性。结果表明，SPU单体的硅氧烷基团能够与牙本质胶原蛋白和羟基磷灰石共价结合。在粘合剂中加入 SPU 导致粘合剂聚合显着增加 (P < 0.05)，断裂拉伸应变高达134.11%。此外，SPU粘合剂显着提高了牙本质粘合强度（P < 0.05），减少了界面纳米渗漏（P < 0.05），并表现出良好的生物相容性。综上所述，应用SPU与牙本质实现双重化学粘合，可以提高混合层质量，缓冲界面应力，增强界面抗水解能力，为延长粘接修复体的使用寿命提供可行的策略。 。