Experimental Study Of The Metal Inner Crown Suitability Factors

objective This experiment study the effect on adaptation of casting metal inner-crown with different coating layers of diespacer .sandblasting time ,different power/liquid of two kind of adhesive cement. Method The average adhesive thickness at different parts of casting metal inner-crowns were measured under travel microscope by cutting method. Results 1. The adhesive thinkness at different parts of crowns with different layers of diespacer on the dies had significant difference compared with the inner-crowns without diespacer on the dies (p<0.05) . 2. There is statistically difference in adhesive thinkness of axial sursive when adopt different time of sandblasting (p<0.05). The margians adaptation were not significantly different. 3. The margians discrepence of zinc phosphate cement(P/L=2:1) and zinc polycarbdxylate cement (P/L=1:1) were 45.04μmand 67.47μm. When the P/L of adhesive cement increase, the margians discrepance of inner-crowns significantly increase (p<0.05). conclusion Coated with one or two layers of diespacer on the dies, controled the time of sandblasting in 3 minites,anhesived with ZP(P/L=2:1) and PC(P/L=1:1) could improve the adaptation of casting metal inner-crowns significantly.