AN EVALUATION OF THE CRACK PROPAGATION CHARACTERISTICS OF PORCELAIN AND THE BOND STRESS OF CERAMO-METAL SYSTEM

치과용 도재의 균열전파 특성과 도재 -금속간의 응력분석

  • Park, Ju-Mi (Dept. of Prosthodontics, College of Dentistry, Chonbuk National University) ;
  • Bae, Tae-Sung (Dept. of Dental Material, College of Dentistry, Chonbuk National University) ;
  • Song, Kwang-Yeob (Dept. of Prosthodontics, College of Dentistry, Chonbuk National University) ;
  • Park, Charn-Woon (Dept. of Prosthodontics, College of Dentistry, Chonbuk National University)
  • 박주미 (전북대학교 치과대학 보철학교실) ;
  • 배태성 (전북대학교 치과대학 치과재료학교실) ;
  • 송광엽 (전북대학교 치과대학 보철학교실) ;
  • 박찬운 (전북대학교 치과대학 보철학교실)
  • Published : 1994.04.01

Abstract

This study was carried out to evaluate the effect of the crack propagation characteristics and bond stress of ceramo-metal system. In order to characterize the crack propagation, the static crack propagation stored in $37^{\circ}C$ distilled water of two commerical porcelains and the dynamic crack propagation under cyclic flexure load of ceramo-metal system were examined. In order to characterize the bond stress, the shear bond test, the 3-point flexure bond test, and the finite element stress analysis of ceramo-metal system were conducted. The results obtained were as follows : 1. Bulk densities and Young's moduli of opaque porcelains increased with repeated firing. 2. Maximum fracture toughness during 4 firing cycles showed at the group of 4 firing cycles in Ceramco porcelain and 2 firing cycles in Vita porcelain. 3. Shear bond strength and flexure bond strength of Ceramco-Verabond specimen were larger than those of Ceramco-Degudent G specimen (p<0.05). 4. Interfacial stresses under three point flexure bond test were concentrated at the edges of ceramometal system. 5. When a cyclic flexure load was applied, the crack growth rate of porcelain surface of ceramometal specimens was decreased as load cycles increased.

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