Monomers and nanogel to improve adhesive resin structural integrity/durability

描述(由申请人提供)：在美国每年进行的超过1亿次的牙科修复治疗中，大部分涉及树脂粘结复合材料的放置，而且人们认识到，牙医花费了大量时间来修改和更换这些修复体，因此显然需要改善临床性能的材料。与牙科汞合金相比，复合修复剂不仅具有美学优势，而且提供了一种将修复体粘结到牙本质和牙釉质上的方法。然而，由于湿法粘合技术带来的挑战，在这一关键界面聚合之前、期间或之后的较长时间间隔内，水诱导相分离的可能性目前无法可靠地获得强劲、完整的边际。该提案描述了新型水相容单体的开发计划，与HEMA相比，它具有提高反应性、避免相分离以及生产化学和机械性能良好的聚合物网络的潜力。开发了一种高度通用的技术来制备纳米级(10-30 nm)聚合物粒子，并控制支化、化学和反应位置。这些反应性纳米凝胶可以在高浓度下很容易地分散在二次单体中，然后渗透到预聚体添加剂中，然后与预聚体添加剂共聚。拟议的项目围绕三个具体目标构建：1)将开发水相容单体作为HEMA的替代品或补充，以更好地保持粘接树脂的均质性和高交联度；2)纳米凝胶改性胶粘剂的积极初步结果将扩展到水分散的反应性纳米凝胶，提供增强的结构均匀度和稳定性，同时引入不能作为游离单体分散在水中的成分；3)微/纳米机械性能表征以及粘结层和界面的成像将共同用作一种分析工具，以更好地了解现有材料中牙本质与粘接树脂之间的相互作用以及本文提出的先进粘接剂的结构和性能。我们期望将胶粘剂树脂相的稳定性与胶原保护策略相关联，包括基于非迁移性纳米凝胶平台的胶原交联、抗菌活性和基质金属蛋白酶抑制特性。这项应用将使人们更好地了解现有粘接系统的优缺点，同时开发新材料，解决粘结式牙科修复体粘结层和混合层中当前存在的结构稳定性和耐久性方面的重大问题。

DESCRIPTION (provided by applicant): With a majority of the more than 100,000 million dental restorative treatments performed in the US each year involving the placement of resin-bonded composite materials, and the acknowledgement that a large portion of a dentist's time is consumed with revising and replacing these restorations, there is a clear need for materials with improved clinical performance. Composite restoratives not only hold an esthetic advantage over dental amalgams, but they offer a means to adhesively bond the restoration to dentin and enamel. However, due to challenges imposed by wet bonding techniques, the potential for water-induced phase separation prior to, during or over extended intervals following polymerization of this critical interface, a strong, intact margin cannot currently be reliably obtained. This proposal describes the development plan for new water compatible monomers that compared with HEMA, offer the potential for improved reactivity, avoidance of phase separation and the production of chemically and mechanically sound polymer networks. A highly versatile technique has been developed for preparing nano-scale (10 - 30 nm) polymeric particles with control over branching, chemistry and reactive site placement. These reactive nanogels can be dispersed readily at high concentrations in secondary monomers, which then infiltrate and subsequently copolymerize with the prepolymer additives. The proposed project is constructed around three specific aims: 1) water-compatible monomers as alternatives to or in addition to HEMA will be developed as a means to better maintain homogeneity and high crosslink densities throughout adhesive resins; 2) the positive preliminary results with nanogel-modified adhesives will be extended into water-dispersible reactive nanogels that provide enhanced structural homogeneity and stability while introducing components that cannot be dispersed in water as free monomers; and 3) micro/nano-mechanical property characterization coupled with imaging of the adhesive layer and interfaces will be collectively used as an analytical tool to better understand structure and properties associated with the interaction between dentin and the adhesive resin in existing materials as well as the advanced adhesives proposed here. We expect to correlate the stabilization of the adhesive resin phase with collagen protection strategies that include collagen crosslinking, anti-bacterial activity and MMP-inhibiting properties based on the non-migrating nanogel platform. The application will provide an improved understanding of the strengths and weaknesses of existing adhesive systems, while developing new materials that address the significant current problems of structural stability and durability within the adhesive and hybrid layers of bonded dental restorations.