Dental Composites from Photoresponsive Addition-Fragmentation Filler Particles

由光响应加成-断裂填充颗粒制成的牙科复合材料

• 批准号: 9886076
• 负责人: Nick Bongiardina
• 金额: $ 4.1万
• 依托单位: UNIVERSITY OF COLORADO
• 依托单位国家: 美国
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-05-01 至 2021-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9886076
• 关键词: Address; Amalgam; Appearance; Area; Behavior; Biocompatible Materials; Biological; Chemicals; Chemistry; Complex; Composite Dental Resin; Composite Resins; Conflict (Psychology); Dental; Dental Materials; Development; Esthetics; Ethics; Excision; Failure; Filler; Formulation; Fracture; Free Radicals; Goals; Growth; Hydrogen Bonding; Industrialization; Kinetics; Knowledge; Lead; Learning; Light; Measurable; Measures; Mechanics; Mentors; Methacrylates; Methodology; Methods; Modulus; Network-based; Organic Synthesis; Performance; Phase; Plant Resins; Polymers; Property; Reaction; Relaxation; Research; Scheme; Shapes; Silicon Dioxide; Stress; Structure; Sulfhydryl Compounds; Surface; System; Tooth Fractures; Tooth structure; Training; Viscosity; base; clinical implementation; covalent bond; crosslink; dental resin; design; experience; improved; interfacial; mechanical properties; monomer; nanocomposite; nanoparticle; particle; photopolymerization; polymerization; premature; prevent; response; restoration; restoration placement; restorative composite; restorative dentistry; restorative material; stress reduction; stress state

Project Summary. The proposed research involves the development of crosslinked organic filler particles and surface- modified inorganic fillers that are functionalized with radical addition-fragmentation chain transfer (AFT) moieties for stress reduction in dental restorative composites. Although there have been significant advances in the design of functionalized inorganic fillers and addition of AFT monomers to the resin (polymerizable) phase, stress development during polymerization is still a significant issue in dental restoratives that can lead microcracking of the composite, delamination from the tooth, or even tooth fracture. The design of functional, crosslinked AFT-based particles and subsequent implementation into classic dental resins will enable covalent bond rearrangement within the filler particle to relax stress as it develops. Similarly, incorporation of AFT moieties onto the surface of inorganic fillers is an additional method to introduce dynamic chemistry to the filler phase while maintaining the same mechanical properties of the resin. The purposed research will address stress concentration on the filler and filler/resin interface by taking advantage the Covalent Adaptable Networks (CANs) paradigm. This approach replaces the static bonds that normally exist in a crosslinked network with dynamic bonds that rearrange to a lower stress state in the presence of proper activating species. In the case of AFT, the activating species are free radicals, which are also the active species during the photopolymerization of the dimethacrylate based resins used in most dental restorative composites. The first aim is to develop AFT particles that reduce stress development both during polymerization and upon external loading of classic glassy systems, then implement these particles directly as an additive to standard dental resin formulations and study their effect on the stress behavior. Next, we will develop AFT organic/inorganic nanocomposite particles with functionalized silica nanoparticles to circumvent limitations such as resin viscosity and modulus of the composite. The second aim is to functionalize silica nanoparticles with AFT moieties to enable bond exchange only at the filler/matrix interface without maintaining the mechanical properties of the final composite. We will then incorporate the both the organic AFT particles and the functionalized to investigate possible synergistic effects of both particle types in a dental composite. To accomplish these goals, the purposed training plan will enable trainee to interact with mentors and learn from their technical and practical experience with dental materials. The selected mentoring committee has extensive experience with synthesis, characterization of polymeric dental materials, and clinical implementation, and industrial considerations. The trainee will receive relevant and meaningful training in research-oriented areas and conducting research both thoughtfully and ethically.

项目摘要。 拟议的研究涉及交联有机填料颗粒和表面-的开发 通过自由基加成断裂链转移 (AFT) 功能化的改性无机填料 牙科修复复合材料中用于减少应力的部分。尽管已经取得了重大进展 功能化无机填料的设计以及将 AFT 单体添加到树脂（可聚合）相中， 聚合过程中的应力发展仍然是牙科修复体中的一个重要问题，可能导致 复合材料的微裂纹、牙齿分层，甚至牙齿断裂。功能性的设计， 交联的基于 AFT 的颗粒以及随后应用到经典牙科树脂中将使共价 填料颗粒内的键重排可在应力产生时释放应力。同样，合并 AFT 无机填料表面上的部分是向填料引入动态化学的另一种方法 相，同时保持树脂相同的机械性能。 该研究将通过采取以下措施解决填料和填料/树脂界面上的应力集中问题： 充分利用共价自适应网络 (CAN) 范式。这种方法取代了静态键 通常存在于具有动态键的交联网络中，在存在时会重新排列到较低的应力状态 适当的活化物种。就 AFT 而言，活化物质是自由基，也是活性物质 大多数牙科修复材料中使用的二甲基丙烯酸酯树脂光聚合过程中的物质 复合材料。第一个目标是开发 AFT 颗粒，以减少聚合过程中的应力发展 并在经典玻璃系统的外部加载后，将这些颗粒直接作为添加剂 标准牙科树脂配方并研究它们对应力行为的影响。接下来我们将开发AFT 具有功能化二氧化硅纳米颗粒的有机/无机纳米复合颗粒以避免限制 例如复合材料的树脂粘度和模量。第二个目标是功能化二氧化硅纳米颗粒 具有 AFT 部分，仅在填料/基质界面处实现键交换，而无需保持 最终复合材料的机械性能。然后我们将有机 AFT 颗粒和 功能化以研究牙科复合材料中两种颗粒类型可能的协同效应。 为了实现这些目标，有针对性的培训计划将使受训者能够与导师互动并 学习他们在牙科材料方面的技术和实践经验。选定的指导委员会有 在聚合牙科材料的合成、表征和临床实施方面拥有丰富的经验， 和工业方面的考虑。学员将接受以研究为导向的相关且有意义的培训 领域并深思熟虑和道德地进行研究。