Multifunctional, Non-thermal Plasmas for Long-lasting Dental Adhesion

描述（由申请人提供）：本提案的科学目标是采用由非热等离子体诱导的新的表面/界面化学/功能来实现坚固耐用的牙本质粘附，从而显着延长树脂基牙齿修复体的寿命。提出的研究源于牙科修复长期面临的关键挑战：基于复合树脂的牙科修复体失败率高得令人望而却步。过早失效的一个主要原因是复合树脂与牙本质之间缺乏紧密和持久的粘附。目前最先进的粘合技术无法形成紧密的树脂/牙本质粘合是由于三个主要因素。首先，树脂与牙本质胶原蛋白之间的结合很差，这种结合依赖于粘附树脂与暴露的胶原原纤维的浸润和随后的缠结。微机械联锁机制本身就存在问题，因为渗透不足、聚合不完全和溶剂/水膨胀都阻碍了紧密粘附的形成。其次，牙本质基质的稳定性和质量往往较差。当复合树脂附着的基础本身就摇摇欲坠时，实现持久修复不仅具有挑战性，而且是不可能的。第三，渗透树脂聚合物的强度和质量通常较差，主要原因是目前的粘合剂在口腔环境下聚合不完全。在这个提议中，多功能非热等离子体与明智的工程化学将被用来同时解决这三个关键问题。这种新颖的多功能等离子体技术具有以下独特的特点/功能：1)对蛀牙区域进行消毒，消除残留的致龋微生物；2)使氟化物直接传递到牙本质底物，抑制脱矿/细菌攻击，从而减少复发性龋齿，提高牙本质底物的稳定性；3)提供可控的等离子体化学，以原位和按需定制表面能，以增强粘合剂对暴露的胶原原纤维的渗透；4)参与树脂基体中的网络聚合和交联反应，从而提高树脂基体的单体/聚合物转化率和交联密度，从而生产出更有凝聚力和耐降解的树脂基体；5)通过增强树脂保护，提高牙本质底物抗生物降解的稳定性；6)在粘接剂树脂和胶原原纤维之间产生化学/共价键，从而提高粘接剂/牙本质的结合强度。将利用各种表征技术来彻底阐明等离子体处理对牙本质和粘接剂表面/界面的影响。目标不仅是确认设计原则和工程等离子体技术/化学工作，而且要深入了解它们是如何以及为什么这样做的。

DESCRIPTION (provided by applicant): The scientific objective of this proposal is to employ new surface/interface chemistries/functionalities induced by non-thermal plasmas for robust and durable dentin adhesion, thus significantly extending the longevity of resin-based tooth restorations. The proposed research stems from the critical challenge long facing restorative dentistry: dental restorations based on composite resins have a prohibitively high failure rate. One primary reason for the premature failure is the lack of a tight and long-lasting adhesion between the composite resin and the underline dentin. The inability of the current state-of-the-art bonding techniques to form a tight resin/dentin adhesion is due to three major factors. First, the bonding between resin and dentin collagen, which relies on the infiltration and subsequent entanglement of adhesive resins with exposed collagen fibrils, is poor. The micromechanical interlocking mechanism is intrinsically problematic as insufficient penetration, incomplete polymerization and solvent/water swelling all prohibit the formation of a tight adhesion. Second, the stability and quality of the dentin substrates is often poor. When the foundation to which composite resins adhere is itself shaky, achieving long-lasting restoration is not just challenging, but impossible. Third, the strength and quality of infiltrated resin polymers is usually poor due chiefly to the incomplete polymerization of current adhesives under oral environment. In this proposal, multifunctional non-thermal plasmas with judiciously engineered chemistries will be utilized to simultaneously address all three critical issues. Such a novel and multifunctional plasma technique has the following unique features/functions: 1) sterilize the area of cavity, eliminating residual caries-causing microorganisms; 2) enable direct fluoride delivery to dentin substrates to inhibit demineralization/bacterial attack, thus reduce recurrent caries and improve dentin substrate stability; 3) provide controllable plasma chemistries to tailor the surface energy in-situ and on-demand for enhanced adhesive penetration into exposed collagen fibrils; 4) participate in network polymerization and crosslinking reactions in resin matrix, consequently increase the monomer/polymer conversion and crosslinking density of the resin matrix and thus producing a more cohesive and degradation-resistant resin matrix; 5) improve the stability of the dentin substrates against biodegradation through enhanced resin protection; 6) yield a chemical/covalent bonding between adhesive resins and collagen fibrils, thus enhancing the adhesive/dentin bond strength. Various characterization techniques will be utilized to thoroughly elucidate the plasma treatment effects on the dentin and adhesive surface/interface. The goal is not only to confirm that the design principles and the engineered plasma technology/chemistries work, but also gain deep understanding into how and why they do.