Im/Miscible Adhesive/Dentin Interface:Structure/Mechanic

产品说明：如果复合树脂被认为是牙科汞合金的可行替代品，则必须改善牙本质/粘合剂（d/a）粘合的耐久性。在体内条件下，这种结合可以是对渗透并最终破坏复合修复体的物质的第一道防御。d/a键的耐久性直接关系到HL的质量，但测量质量一直是一个棘手的问题。到目前为止，我们的大多数技术都提供了间接评估，例如，测量本体D/A试样在浸水前后的抗断裂性的测试方法不足以灵敏地识别水降解开始的界面缺陷。我们最近原位表征的分子结构和微观力学的混合层已经表明了一个严重的限制-物理分离的BisGMA/HEMA粘合剂与水混合后，在脱矿牙本质。关键的二甲基丙烯酸酯（BisGMA），对交联聚合物粘合剂贡献最大的组分，渗透了一部分湿的脱矿牙本质。这项工作的总体假设是，在潮湿的临床相关牙本质表面的存在下，与最先进的商业粘合剂相比，配制成包括水相容性组分的甲基丙烯酸酯基粘合剂将提供减少的相分离，从而增强混合层的结构完整性和增加的耐久性。1）甲基丙烯酸酯基粘合剂配方中的阳离子表面活性剂、水相容性光引发剂和水相容性交联二甲基丙烯酸酯共聚单体将减少在水中发生的相分离，并协同作用以减少与这种相分离相关的有害影响; 2）这些与水相容的组分配制的粘合剂将提供增强的牙本质渗透并且可与健康和龋齿影响的牙本质的湿脱矿物质基质混溶，假定合适的粘度;（3）甲基丙烯酸酯对健康牙本质和龋坏牙本质界面弹性模量的影响。显示出降低的相分离和水相容特性的基于粘合剂在暴露于水性环境时将是稳定的，并且界面弹性模量将不会导致应力集中，应力集中将导致在界面处的失效开始。加载过程中的界面; 4）与现有技术的商业粘合剂相比，在湿脱矿健康牙本质基质存在下，表现出减少的相分离、增强的渗透、改善的相容性和结构完整性的甲基丙烯酸酯基粘合剂将提供牢固、持久的D/A粘结。

DESCRIPTION: If composite resins are to be considered a viable alternative to Dental amalgam, the durability of the dentin/adhesive (d/a) bond must be improved. Under in vivo conditions, this bond can be the first defense against substances that penetrate and ultimately undermine the composite restoration. The durability of the d/a bond is directly related to the quality of the HL but measuring quality has been a formidable problem. To date, the majority of our techniques have provided an indirect assessment, e.g., testing methods that measure fracture resistance of bulk d/a specimens pre- and post-water immersion are not sensitive enough to identify interfacial defects where aqueous degradation begins. Our recent in situ characterization of the molecular structure and micro-mechanics of the hybrid layer has indicated a serious limitation-physical separation of the BisGMA/HEMA adhesive upon mixing with water in the demineralized dentin. The critical dimethacrylate (BisGMA), the component contributing most to the cross-linked polymeric adhesive, infiltrated a fraction of the wet, demineralized dentin. The overall hypothesis of this work is that in the presence of moist clinically relevant dentin surfaces, methacrylate-based adhesives formulated to include water-compatible components will provide decreased phase separation and thus, enhanced structural integrity and increased durability of the hybrid layer as compared to state-of-the-art commercial adhesives. The Specific Aims will test the hypotheses: 1) cationic surfactants, water compatible photoinitiators and water-compatible cross-linking dimethacrylate co-monomers in methacrylate-based adhesive formulations will decrease phase separation that occurs in water and act synergistically to reduce the detrimental effects associated with such phase separation; 2) these adhesives formulated with water-compatible components will provide enhanced dentin infiltration and be miscible with wet demineralized matrices of healthy and caries-affected dentin, assuming suitable viscosity; 3) the module of elasticity at the interface of healthy dentin and caries-affected dentin with methacrylate-based adhesives exhibiting reduced phase separation and water compatible characteristics will be stable upon exposure to aqueous environments and that the interfacial elastic moduli will not lead to stress concentration that will result in failure initiation at the interface during loading; 4) that methacrylate-based adhesives exhibiting reduced phase separation, enhanced infiltration, improved miscibility and structural integrity in the presence of wet demineralized healthy dentin matrices will provide strong, durable d/a bonds as compared to state-of-the-art commercial adhesives.