| Objective:The adjusted specimens were treated by means of polishing, glazing after polishing, glazing, grinding and polishing after glazing. To compare the effect of different disposals on the surface character, the results could provide the experimental evidence to choose of surface treatment.Methods: 1 Specimens preparation: A cylindrical metal die of producing metal-based film was produced with precision machine. The diameter of die was 10mm. 24 war patterns were made with plastic method on 0.5mm thick wax finished, spruling, conventional embedding, casting. The casting cobalt-chromium alloy film was polished to 0.4 mm, Al2O3 sandblasting. In accordance with rules that manufacturer provided, the ceramic was sintered, and the thickness was 1.5mm. The subject faces of all specimens were polished with 180﹟water-abrasive paper along the same direction. The specimens of homogeneous adjustment with green grinding wheel were randomly divided into four groups, and each group contains six specimens. Every group was used different surface treatment: A: polishing group: The specimens were polished followed by a coarse-to-fine with Shofu Porcelain Adjustment Kit, one minute for each level of polishing. B: glazing after polishing group: glazing on A group C: glazing group:glazing D: grinding and polishing after glazing group: The specimens were polished followed by a coarse-to-fine with Shofu Porcelain Adjustment Kit, after green grinding wheel homogeneous adjustment 0.1mm on C group, one minute for each level of polishing. (Making use of distilled water ultrasonic cleaning 5 minutes before replacement abrasives and glazing)2 Measurement of surface roughness: A surface roughness tester was used to measure the value of surface roughness (Ra) of every specimen. Three points were selected and the mean of the roughness value of the three points was considered to be the surface roughness value of the specimen.3 All values were analyzed by SPSS 13.0 to compare the difference between the surface roughness of each group.4 The surface feature of the tested specimen was observed by the Stereoscopic Microscope .5 The surface feature of the tested specimen was observed by Scanning Electron Microscope (SEM).Results:1 The surface roughness value of each group. The mean value of surface roughness of each group: group A: 0.297±0.011um, group B: 0.195±0.013 um, group C: 0.300±0.012 um, group D: 0.299±0.010 um2 The values of Specimen surface roughness were analyzed: Analysis of variance (ANOVA) results indicated that there was significant difference of surface roughness values on specimen with different treatment. Multiple comparison results indicated that there were no significant difference in surface roughness values between group A and C, group A and D, C and D. There were differences between A and B, B and C, B and D.3 The specimen surface was observed by Stereoscopic Microscope In group A, the surface was relatively smooth, in which there were uneven air bubbles and pore. In group B, the surface was smooth, and glazing improved surface gloss because of glaze layer. In group C, the surface was relatively smooth, and there were equally distributed pores in the surface. In group D, the surface was similar to group A.4 The specimen surface was observed by Scanning Electron Microscope. In group A, the surface was relatively uneven, in which there were cracks and air bubbles. The texture of polishing and shadow was visible. In group B, the surface was smooth, in which no obvious cracks and air bubbles were visible because of glaze layer. In group C, the surface was relatively smooth, in which there were gathered crystal groups and shallow cracks. In group D, the surface was relatively uneven, in which there were shallow cracks and shadow.Conclusion: 1 There were no significant differences in surface roughness values in polishing and glazing, and the gloss was similar.2 There was the best surface glazing after polishing.3 Glazed ceramic of without fine polishing was polished after grinding, which was similar to glazed ceramic of without fine polishing in gloss.
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