Department of Materials Science and Engineering, University of Washington, Seattle, Washington 98195, United States.
Department of Bioengineering, Izmir Institute of Technology, Urla, Izmir 35430, Turkey.
ACS Biomater Sci Eng. 2023 Mar 13;9(3):1486-1495. doi: 10.1021/acsbiomaterials.2c01039. Epub 2023 Feb 28.
Exposure of dentin tubules due to loss of protective enamel (crown) and cementum (root) tissues as a result of erosion, mechanical wear, gingival recession, etc. has been the leading causes of dentin hypersensitivity. Despite being a widespread ailment, no permanent solution exists to address this oral condition. Current treatments are designed to alleviate the pain by either using desensitizers or blocking dentin tubules by deposition of minerals or solid precipitates, which often have short-lived effects. Reproducing an integrated mineral layer that occludes exposed dentin with concomitant peritubular mineralization is essential to reestablish the structural and mechanical integrity of the tooth with long-term durability. Here, we describe a biomimetic treatment that promotes dentin repair using a mineralization-directing peptide, sADP5, derived from amelogenin. The occlusion was achieved through a layer-by-layer peptide-guided remineralization process that forms an infiltrating mineral layer on dentin. The structure, composition, and nanomechanical properties of the remineralized dentin were analyzed by cross-sectional scanning electron microscopy imaging, energy dispersive X-ray spectroscopy, and nanomechanical testing. The elemental analysis provided calcium and phosphate compositions that are similar to those in hydroxyapatite. The measured average hardness and reduced elastic modulus values for the mineral layer were significantly higher than those of the demineralized and sound human dentin. The structural integration of the new mineral and underlying dentin was confirmed by thermal aging demonstrating no physical separation. These results suggest that a structurally robust and mechanically durable interface is formed between the interpenetrating mineral layer and underlying dentin that can withstand long-term mechanical and thermal stresses naturally experienced in the oral environment. The peptide-guided remineralization procedure described herein could provide a foundation for the development of highly effective oral care products leading to novel biomimetic treatments for a wide range of demineralization-related ailments and, in particular, offers a potent long-term solution for dentin hypersensitivity.
由于侵蚀、机械磨损、牙龈退缩等原因，牙本质小管暴露于保护性的牙釉质（牙冠）和牙骨质（牙根）组织中，这是牙本质过敏的主要原因。尽管这是一种普遍的疾病，但目前还没有永久性的解决方案来解决这种口腔问题。目前的治疗方法是通过使用脱敏剂或通过矿物质或固体沉淀物的沉积来阻塞牙本质小管来缓解疼痛，这些方法往往效果短暂。通过沉积矿物质或固体沉淀物来阻塞暴露的牙本质并伴随小管周围矿化来复制一个整合的矿化层，对于恢复牙齿的结构和机械完整性具有长期耐久性至关重要。在这里，我们描述了一种使用来源于釉原蛋白的矿化导向肽 sADP5 促进牙本质修复的仿生治疗方法。通过层状肽引导的再矿化过程实现了封闭，该过程在牙本质上形成了一个渗透矿化层。通过横截面扫描电子显微镜成像、能量色散 X 射线能谱和纳米力学测试分析了再矿化牙本质的结构、组成和纳米力学性能。元素分析提供了类似于羟基磷灰石的钙和磷组成。矿化层的测量平均硬度和弹性模量值明显高于脱矿和健康人牙本质的值。新矿化层和下面牙本质的结构整合通过热老化得到证实，没有物理分离。这些结果表明，在口腔环境中自然经历的长期机械和热应力下，相互渗透的矿化层与下面的牙本质之间形成了一个结构坚固、机械耐用的界面。本文所述的肽引导再矿化程序可以为开发高效的口腔护理产品提供基础，从而为广泛的脱矿相关疾病提供新的仿生治疗方法，特别是为牙本质过敏症提供一种有效的长期解决方案。
