Formation of the Enamel-Dentin Interface

建议的研究的目的是提高我们对基本物理化学的理解 初始釉质矿化和牙本质-釉质界面形成的机制。釉质 矿化开始于矿化牙本质层的表面，这可能在初始矿化过程中起重要作用。 釉质形成牙本质和牙釉质是两种矿化组织，具有显著不同的力学和生物力学特性。 结构性能，通常共同执行了几十年，没有失败。这么优秀的 机械耐久性要求这两种组织之间有非常强的结合。牙齿研究- 相关的遗传疾病和基因敲除动物证明， 界面对于正常的牙齿功能至关重要。界面稳定性的问题也很重要 对于组织修复，由于组织之间的弱界面， 修复材料。牙本质和牙釉质组织在初始矿化过程中的相互作用可能 在这个至关重要的界面的正确形成中发挥重要作用。我们假设 在釉质和牙本质之间的边界处的矿化的开始是高度整合的， 这是一个特殊的过程，对于正确形成这种机械坚固的界面至关重要。我们也 假设在该界面处初始釉质形成的机制不同于其他界面， 釉质形成的阶段。我们已经确定了区分初始釉质形成的三个主要因素 从釉质形成的后期阶段：1）在初始釉质形成的部位存在牙本质矿物; 2） 瞬时矿物相的存在;和3）在初始矿物相的位置处的独特的大分子组合物 釉质形成因此，我们建议对牙本质-釉质界面的形成进行全面的研究 使用各种体内和体外方法，以更好地了解 初始釉质形成。具体来说，我们在目标1中提出：研究牙本质和 在初始釉质矿化部位的釉质晶体，特别强调外延关系 目的2：研究牙本质和釉质晶体之间的瞬时无定形矿物相的作用， 目的3：研究牙釉质形成初期的大分子组成， 釉质矿化位点，特别强调蛋白质-矿物质相互作用，并阐明 这些大分子和超分子组装体在初始釉质形成中的可能功能 使用机械方法，在一系列体外矿化实验中。我们希望结果 本研究的结果将提高我们对形成过程中所涉及的基本过程的了解 牙本质-牙釉质界面，这将有望导致新的先进材料的开发和/或 矿化组织修复的程序。

The purpose of the proposed studies is to improve our understanding of the basic physico-chemical mechanisms of initial enamel mineralization and formation of the dentin-enamel interface. Enamel mineralization starts at the surface of a layer of mineralized dentin, which may play an important role in initial enamel formation. Dentin and enamel are two mineralized tissues with strikingly different mechanical and structural properties that normally perform jointly for tens of years, without failure. Such an outstanding mechanical endurance requires an extraordinarily strong bond between these two tissues. Studies of tooth- related genetic disorders and knockout animals demonstrate that the correct formation of the dentin-enamel interface is essential for the proper tooth function. The problem of interface stability is also very important with respect to tissue repair, where often implant failure occurs due to a weak interface between tissues and repair materials. It is likely that interactions between dentin and enamel tissues during initial mineralization play an important role in the proper formation of this critically important interface. We hypothesize that the onset of mineralization at the boundary between enamel and dentin is a highly integrated and specialized process, essential for the proper formation of this mechanically robust interface. Wealso hypothesize that the mechanism of initial enamel formation at this interface is different from other stages of amelogenesis. We have identified three major factors that distinguish initial enamel formation from later stages of amelogenesis: 1) the presence of dentin mineral at the site of initial enamel formation; 2) the presence of transient mineral phases; and 3) a unique macromolecular composition at the site of initial enamel formation. Thus, we propose a comprehensive study of the formation of the dentin-enamel interface using a variety of in vivo and in vitro approaches to gain a better understanding of basic mechanisms of initial enamel formation. Specifically, we propose in Aim1: To study the interactions between dentin and enamel crystals at the site of initial enamel mineralization, with special emphasis on the epitaxial relationship between dentin and enamel crystals; in Aim 2: To study the role of transient amorphous mineral phases in initial stages of enamel formation; and in Aim 3: To study the macromolecular composition at the initial enamel mineralization site with special emphasis on protein-mineral interactions, and to elucidate the possible functions of these macromolecules and supra-molecular assemblies in initial enamel formation using a mechanistic approach, in a series of in vitro mineralization experiments. We expect that the results of this study will improve our knowledge of the basic processes involved in the formation of the dentin-enamel interface that will hopefully lead to the development of new advanced materials and/or procedures for mineralized tissue repair.