Analysis of Chemical Composition, Microstructure and Hydroxyapatite Structure for Mouse Teeth

생쥐 치아의 화학적 조성, 미세구조 및 Hydroxyapatite 구조 분석

  • Kim, Eun-Kyung (Graduate School of Analytical Science and Technology, Chungnam National University) ;
  • Jeon, Tae-Hoon (Graduate School of Analytical Science and Technology, Chungnam National University) ;
  • Kim, Chang-Yeon (Graduate School of Analytical Science and Technology, Chungnam National University) ;
  • Nam, Seung-Won (Department of Bioscience and Biotechnology, Chungnam National University) ;
  • Song, Kyung (Division of Electron Microscopic Research, Korea Basic Science Institute) ;
  • Lee, Sang-Gil (Division of Electron Microscopic Research, Korea Basic Science Institute) ;
  • Kim, Youn-Joong (Graduate School of Analytical Science and Technology, Chungnam National University)
  • 김은경 (충남대학교 분석과학기술대학원) ;
  • 전태훈 (충남대학교 분석과학기술대학원) ;
  • 김창연 (충남대학교 분석과학기술대학원) ;
  • 남승원 (충남대학교 생명과학과) ;
  • 송경 (한국기초과학지원연구원 전자현미경연구부) ;
  • 이상길 (한국기초과학지원연구원 전자현미경연구부) ;
  • 김윤중 (충남대학교 분석과학기술대학원)
  • Received : 2010.08.28
  • Accepted : 2010.09.28
  • Published : 2010.09.30

Abstract

The aim of this study is to determine microstructure, chemical composition and crystal structure of hydroxyapatite for mouth teeth using optical microscopy and electron microscopy as well as electron probe micro-analysis (EPMA). Enamel, a protective cover to the teeth, consisted of rods oriented in regular and had relatively higher crystallinity and Ca component. In contrast, dentin showed a sponge-like microstructure with circular holes which were passages of dentinal tubules, and had higher Mg component than the enamel region due to its higher organic content. Hydroxyapatite crystals appeared as large rods in enamel, but as small needles in dentin. Their electron diffraction patterns were different by their crystallinity as well as by the organic content of the matrix.

본 연구에서는 광학 및 전자현미경 관찰과 전자현미분석을 수행하여 쥐 치아의 미세구조, 화학 조성 및 hydroxyapatite의 결정구조를 파악하였다. 치아의 겉 표면을 둘러싸고 있는 법랑질은 막대들이 일정하게 배열된 구조이며 결정도가 높고 Ca이 많이 침착되어 있다. 그에 비해 상아질은 상아세관이 통과하는 원형의 구멍이 고루 분포되어 있는 스펀지 구조이며 유기질의 존재로 인해 Mg의 분포가 법랑질에 비해 상대적으로 높게 나타났다. Hydroxyapatite 결정들은 법랑질에서는 크기가 큰 막대 형태로 나타났으나 상아질에서는 크기가 작은 침상 형태로 나타났으며, 각 조직의 결정도와 유기질의 유무에 따라 전자회절패턴의 차이를 보였다.

Keywords

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