| 摘要 |
PURPOSE:To obtain a dental ceramic material frame capable of producing an all ceramic crown having excellent strength and toughness and three or more crowns. CONSTITUTION:Ceramic constituting porcelain is made of a porous layer comprising spherical alumina and alumina fine powder. Since this porous ceramic layer has no cracks caused by shrinkage in burning, acts as a structural material to secure strength and toughness as a porcelain core material, particle size of spherical alumina and alumina fine powder constituting ceramic raw material powder is controlled, strength and a pore distribution capable of being impregnated with glass can be secured. Since a dental ceramic material frame of this invention is impregnated with glass, strength and toughness as a ceramic core material is ensured. Further, since a glass composition for impregnation contains La2O3 and Al2O3 and ZrO2 or Y2O3, viscosity advantageous for improvement in strength and hardness and impregnation can be maintained. |
