The Glossiness of Ceramics by Differences Polishing Appliances

Objectives: Because the color of ceramics is similar to that of the natural tooth crown, they are frequently used in clinical cases due to increases in requests for esthetically satisfactory treatment. In this study, the glossiness of ceramics at each polishing stage was measured and evaluated.
Methods: As ceramic materials, we used VITA BLOCS MarkII (VITA) (VITA Co.), IPS e.max Press (IPS)(Ivoclar vivadent Co.), and Initial LiSi Press (LiSi)(GC Co.). VITA was cut to a thickness of 3 mm as a measurement specimen. For IPS and LiSi, wax was used to fill a silicon mold of 13 x 10 x 3 mm, and a wax pattern was produced. Specimen rods were softened and pressure forming was performed to produce measurement specimens. These specimens were polished using #600 water-resistant polishing papers. Polishing appliance was used porcelain ceramic polisher(Cp) (Kerr Co.),Meisinger LiSi Twist(Li)(GC Co.),CERASHAIN(Ce)(GC Co.). At each polishing stage, glossiness was measured using a glossimeter (GV-2000, NIPPON DENSYOKU Co.). In each specimen, polishing was performed at a polishing pressure of 150 g for 20 seconds. Three measurements of each specimen were evaluated using two-way analysis of variance.
Results: The glossiness of ceramics in final polishing was 36.2 in VITA, 76.4 in IPS, and 75.4 in LiSi. Although a significant difference was noted between VITA and LiSi;IPS, no significant difference was present between IPS and LiSi. Regarding the glossiness at polishing appliances, it was 53.3 at Cp , 71.4 at Li, and 63.4 at Ce. The glossiness of ceramics was highest in IPS at final polishing using Li.
Conclusions: The glossiness of ceramics varied with the polishing appliances used. The glossiness of ceramics increased with decreases in the roughness of polishing materials. Therefore, in clinical cases, it is necessary to polish up to final polishing.