A SCANNING ELECTRON MICROSCOPIC STUDY ON THE CORROSION RESIST ANCE OF CHEMICALLY AND THERMALLY RECYCLED METAL BRACKETS

화학처리(化學處理) 및 열처리(熱處理)한 재생금속(再生金屬) Bracket의 내식성(耐蝕性)에 관(關)한 주사전자현미경적(走査電子顯微鏡的) 연구(硏究)

  • Yoon, Young Joo (Dept. of Orthodontics, College of Dentistry, Chosun University) ;
  • Lee, Dong-Joo (Dept. of Orthodontics, College of Dentistry, Chosun University)
  • 윤영주 (조선대학교 치과대학 교정학교실) ;
  • 이동주 (조선대학교 치과대학 교정학교실)
  • Published : 1989.07.30

Abstract

The purpose of this study was to evalute the corrosion resistance of chemically and thermally recycled metal brackets. In vivo, two types of recycled metal brackets and new brackets were directly bonded for 1 year, and then the microstructure of bracket surface was examined by S.E.M. (J.S.M.-840 Scanning Electron Microscope, Japan). The following results were obtained. 1) The microstructure of new and chemically recycled metal bracket surfaces showed regular structure without island formation and recrystallization; and after 1 year, the same appearance except some scratches. 2) The microstructure of thermally recycled metal bracket surfaces showed a beginning of island formation and recrystallization by annealing, and after 1 year, a typical corrosive appearance, completely island formation with some metal grains by recrystallization. 3) Chemically recycled metal brackets showed better corrosion resistance than thermally recycled metal brackets.

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