Degassing 조건이 Ni-Cr 합금의 도재결합력에 미치는 영향

EFFECT OF DEGASSING CONDITION ON CERAMIC BOND STRENGTH OF Ni-Cr ALLOYS

  • 이은화 (부산대학교 치과대학 치과보철학교실) ;
  • 전영찬 (부산대학교 치과대학 치과보철학교실) ;
  • 정창모 (부산대학교 치과대학 치과보철학교실) ;
  • 임장섭 (부산대학교 치과대학 치과보철학교실)
  • Lee, Eun-Hwa (Department of Prosthodontics, College of Dentistry, Pusan National University) ;
  • Jeon, Young-Chan (Department of Prosthodontics, College of Dentistry, Pusan National University) ;
  • Jeong, Chang-Mo (Department of Prosthodontics, College of Dentistry, Pusan National University) ;
  • Lim, Jang-Seop (Department of Prosthodontics, College of Dentistry, Pusan National University)
  • 발행 : 2000.05.01

초록

This study evaluated the effect of degassing on the ceramic bond strength of two Ni-Cr alloys under varying holding time at the upper limit temperature and atmospheric conditions. Metal specimens were divided into 5 groups for each alloy according to degassing conditions prior to porcelain application no degassing, degassing under vacuum without hold, degassing under vacuum with hold for 5 min. and 10 min. respectively at the upper limit temperature and degassing in air. Total number of metal ceramic specimens was eighty and each group had eight specimens. The ceramic bond strength was measured by four-point flexural test using Instron and the fractured surface was examined under SEM. The results obtained were as follows. 1. Degassing in air improved the ceramic bond strength of Ni-Cr alloys. 2. In degassing under vacuum, hold at the upper limit temperature was advantageous to the ceramic bonding of Ni-Cr alloys. 3. After ceramic metal bond test, metal surfaces were partially covered with the thin porcelain layer, and the cohesive failures in porcelain were predominant in groups showing higher ceramic bond strength.

키워드