牙本质结合微环境的富水性质,再加上粘结界面上的应力,有助于混合层的水解降解,导致粘接耐久性下降,最终,恢复失败。目前,三步蚀刻和冲洗技术仍然是牙本质结合的黄金标准,键合机制主要涉及物理相互作用,几乎没有化学键合。在这项研究中,我们开发了一种硅氧烷改性的聚氨酯单体(SPU),其丙烯酸酯和硅氧烷改性可与牙本质中的胶原和羟基磷灰石化学结合。配制为双酚A-甲基丙烯酸缩水甘油酯替代品,SPU单体基粘合剂旨在提高牙本质粘合质量和耐久性。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在SPU处理的胶原蛋白上进行,羟基磷灰石,和酸蚀牙本质切片成牙本质。对所配置的SPU粘合剂的物理化学性能进行了分析,以了解其聚合行为,水接触角,以及拉伸应变和强度。通过微拉伸强度评估粘合有效性,在热循环老化前后对粘结样品进行纳米泄漏测试。最后,我们进一步进行了体内和体外实验,以评估粘合剂的生物相容性。结果表明,SPU单体的硅氧烷基团可以共价结合牙本质胶原和羟基磷灰石。在粘合剂中掺入SPU导致粘合剂聚合显著增加(P<0.05),断裂拉伸应变高达134.11%。此外,SPU粘合剂显著提高了牙本质粘结强度(P<0.05),减少界面纳米渗漏(P<0.05),并表现出良好的生物相容性。总之,SPU的应用,与牙本质实现双重化学键合,可以提高混合层的质量,缓冲界面应力,增强界面对水解的抵抗力,为延长粘接修复体的使用寿命提供了可行的策略。
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.