RELEASE OF DIAGNOSTIC AND CARIES PREVENTIVE AGENTS

如果修复体和牙齿结构之间的粘结因 修复材料的侵蚀或聚合收缩，如果， 在某些条件下，细菌在边缘区域内发生迁移 然后，就可以启动牙齿结构的脱矿。 在修复体附近诊断这种早期脱矿 仍然是一项主观任务，当一个微小的缺口 存在于牙齿修复界面上。射线照相通常不会 检测这些复发的病变；目前，没有更好的技术 可进行比摘除的修复和直接目视检查 寻找白色运动或更严重的损伤的证据。长距离的 项目4的目标是开发一种控制释放系统，由 环境酸碱度的变化，可以纳入其中 用于龋齿诊断和/或保护的修复程序 与修复体相邻的牙齿结构。 该系统应执行以下任务，当 环境达到临界值：a)表示存在早期 通过释放一种明显的标志物来脱矿，临床医生可以 认识到；b)通过以下方式遏制对该地点的继续殖民 致龋菌和由此产生的微隙中的酸分泌；c) 启动脱矿牙本质的再矿化。我们会申请 微球技术来实现这些目标。的优势 微球有三个方面：1)可以负载各种染料作为标记和 治疗药物可储存在微球内；2)微球 可以由各种类型的树脂制成，以形成任何所需的释放 以及3)微球可以被制成以保持其物理性能 即使在完全释放之后也是完整的。在我们目前的中心拨款期间 期间，我们合成了两个主要的pH敏感聚合物系列 释放载体；聚(苯乙烯-共乙烯基吡啶)和聚(苯乙烯-共-N，N，- 甲基丙烯酸二乙氨基乙酯)。已被用于研究的试剂 释放机制包括两种染料(9-氨基吖啶和钠 氟化钠等矿化促进剂，以及 洗必泰、氟离子等抗菌剂。 了解聚合物作为控制释放装置的潜力 并促进用于输送龋病标志物的配方 诊断或生物活性物质到特定部位，我们建议研究 共聚物组成对药剂负载量和pH刺激的影响 从微球中释放。通常，微球需要结合 一些树脂系统将助剂释放到特定的位置。美国政府的影响 树脂体系对微球的释放也将进行测定。 为了提高非离子水诊断系统的有效性 可溶染料将被制成并进行测试。该项目的最终目标是 4是按顺序分析作为组合物函数的释放潜力 为特定的释放率选择理想的系统。对.的使用 还将探索在其他应用中合成的聚合物系统。为 该系统的有效性，发布后还将进行测试 体外和体内的杀菌释放和氟离子释放 细菌培养。在公元04年，我们会进行可行性研究。 为未来临床生成初步数据的诊断系统 学习。

If the bond between the restoration and the tooth structure is broken due to erosion or polymerization shrinkage of restorative materials, and if, under certain conditions, bacterial migration occurs within the marginal gap, then demineralization of tooth structure can be initiated. Diagnosis of such early demineralization adjacent to a restoration remains a subjective task that is complicated further when a microgap exists along the tooth-restoration interface. Radiographs often do not detect these recurrent lesions; currently, no better technique is available than removal of the restoration and direct visual examination for evidence of white sports or more advanced lesions. The long range goal of Project 4 is to develop a controlled-release system driven by the changes in the pH of the environment which can be incorporated as part of the restorative procedure for the caries diagnosis and/or protecting tooth structure adjacent to the restorations. This system should perform the following tasks when the pH of the environment reaches a critical value: a) signal the presence of early demineralization by releasing a distinct marker that the clinician can recognize; b) inhibit the continued colonization of this location by cariogenic bacteria and the resultant acid secretion in the microgap; c) initiate remineralization of the demineralized dentin. We will apply microsphere technology to achieve these goals. The advantages of microspheres are three-fold: 1) one can load various dyes as marker and therapeutic agents can be stored within the microspheres; 2) microspheres can be fabricated from various types of resin to form any desired release profile; and 3) the microspheres can be made to maintain their physical integrity even after complete release. During our current Center grant period, we have synthesized two main series of pH-sensitive plymers as release vehicles; Poly(styrene-co-vinylpridine) and poly(styrene-co-N,N,- diethylaminoethylmethacrylates). Agents which have been used to study release mechanisms include two dyes (9-aminoacridine and sodium flluorescein), mineralization enhancers such as sodium fluoride, and antibacterial agents such as chlorhexidine and fluoride ions. To understand the potential of the polymer as a controlled-release device and to facilitate formulation for delivering markers for caries diagnostic or bioactive agents to specific sites, we propose to study the effect of copolymer composition on agent loading and pH-stimulated release from microspheres. Often the microspheres need to incorporate some resin system to release agents to specific-sites. The effect of the resin system on the release from microspheres will also be determined. To improve the effectiveness of the diagnostic system an non-ionic water soluble dye will be made and tested. The ultimate goal of the Project 4 is to analyze release potential as a function of compositions in order to choose the ideal system for specific release rates. The use of polymer systems synthesized in other applications will be explored. For the effectiveness of the system, the release will also be tested for bactericidal release and fluoride ion release both in vitro and in bacterial culture. At year 04, we will conduct a feasibility study of the diagnostic system to generate preliminary data for future clinical studies.