The Journal of Korean Academy of Prosthodontics (대한치과보철학회지)

The Korean Academy of Prosthodonitics (대한치과보철학회)
권호 표지

CORROSION PHENOMENA OF MAGNETIC ATTACHMENT USED IN ORAL ENVIRONMENT

구강 환경에서 사용된 자성 Dyna 어태치먼트의 부식현상

  • Kwak Jong-Ha (Department of Prosthodontics and Oral Biology Research Institute, College of Dentistry, Chosun University) ;
  • Chung Chae-Heon (Department of Prosthodontics and Oral Biology Research Institute, College of Dentistry, Chosun University) ;
  • Choe Han-Cheol (Department of Dental Laboratory Technology and Metallogical Engineering, Kwangyang University)
  • 곽종하 (조선대학교 치과대학 보철학교실 및 구강생물학연구소) ;
  • 정재헌 (조선대학교 치과대학 보철학교실 및 구강생물학연구소) ;
  • 최한철 (광양대학교 치과기공과 및 제철 금속학과)
  • Published : 2002.10.01
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Abstract

The purpose of this study was to investigate further the mechanics of failure of magnets used for denture retention. Dyna magnets were retrived from denture that had failed after 34 months of clinical use. The magnets were observed and sectioned in order to analyse with high resolution scanning electron microscope. From this study, corrosion behaviors of used magnetic attachment were analysed. The results were as follows ; 1. In Nd-Fe-B based magnetic materials, the erosion-corrosion was started at ununiformed part of stainless steel cover. 2. Corrosion was initiated at weared stainless steel surface and then magnetic materials were spalled by corrosive solution. 3. Spatting was occurred in Nd-Fe-B magnet materials due to corrosion products and then corrosion rate was increased drastically. 4. Corrosion started from ununiformed stainless steel surface as well as welded zone. In conclusion, the failure of magnets may occur by either breakdown of the welding or breakdown of the encapsulating material. So, it is considered that the corrosion problem of dental magnetic materials could be solved to some extent with surface treatment of dental magnetic materials.

Keywords

References

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