Nanoscale chemical and mechanical heterogeneity of human dentin characterized by AFM-IR and bimodal AFM
Nanoscale chemical and mechanical heterogeneity of human dentin characterized by AFM-IR and bimodal AFM
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通过 AFM-IR 和双峰 AFM 表征人类牙本质的纳米级化学和机械异质性
DOI：
10.1016/j.jare.2019.12.004
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发表时间：
2020-03-01
影响因子：
10.7
通讯作者：
Hu, Xiaoli
中科院分区：
文献类型：
--
作者：
Huang, Lijia;Zhang, Xiaoyue;Hu, Xiaoli
牙本质是人体内重要的钙化组织，在承受咀嚼力方面起着重要作用，具有复杂的层次结构。了解牙本质的组成和超微结构对于阐明健康和病理状态下的生物矿化机制至关重要。在这里，原子力显微镜红外光谱（AFM-IR）和基于AFM的振幅调制-频率调制（AM-FM）技术被用来检测在纳米级的管周和管间牙本质之间的化学成分和力学性能的异质性。AFM-IR光谱收集管周和管间牙本质包含类似的振动带的酰胺区（I，II和III），这表明胶原蛋白可能存在于这两种结构。在1336 cm（-1）处的一个独特的带，表明S=O伸缩振动仅在管周牙本质中检测到。AFM-IR成像显示不同部位的化学成分分布不均匀，证实了牙本质的异质性。管周牙本质的杨氏模量较高，并与较高的矿物质含量。本研究表明，管周牙本质具有独特的化学和力学性质，这意味着管周牙本质和管间牙本质的不同发育和矿化过程。AFM-IR可用于提供人类牙本质异质性的成分信息，有助于理解牙本质的矿物沉积机制。(C)2019年，任作家。由Elsevier B. V.代表开罗大学出版。
Human dentin, as an important calcified tissue in the body, plays significant roles in withstanding masticatory forces and has a complex hierarchical organization. Understanding the composition and ultrastructure of dentin is critical for elucidating mechanisms of biomineralization under healthy and pathological states. Here, atomic force microscope infrared spectroscopy (AFM-IR) and AFM-based amplitude modulation-frequency modulation (AM-FM) techniques were utilized to detect the heterogeneity in chemical composition and mechanical properties between peritubular and intertubular dentin at the nanoscale. AFM-IR spectra collected from peritubular and intertubular dentin contained similar vibrational bands in the amide regions (I, II and III), suggesting that collagen may exist in both structures. A distinctive band at 1336 cm(-1) indicative of S=O stretching vibrations was detected only in peritubular dentin. AFM-IR imaging showed an uneven distribution of chemical components at different locations, confirming the heterogeneity of dentin. The Young's modulus of peritubular dentin was higher, and was associated to a higher mineral content. This study demonstrated distinctive chemical and mechanical properties of peritubular dentin, implying the different development and mineralization processes between peritubular and intertubular dentin. AFM-IR is useful to provide compositional information on the heterogeneity of human dentin, helping to understand the mineral deposition mechanisms of dentin. (C) 2019 The Authors. Published by Elsevier B.V. on behalf of Cairo University.