서로 다른 스캔 방식을 이용하여 CAD/CAM에 의해 제작된 coping의 내면 및 변연 적합성에 관한 고찰.

Abstract

The purpose of this study is to evaluate the marginal and internal fit of coping made by CAD/CAM using different scanning methods. Zirconia coping was made by each CAD/CAM system followed by intra-oral scanning, model optical scanning and model contact scanning. Each coping was cemented to each abutment with RelyXTM UniCem(3M ESPE AG, Seefeld, Germany). It was embedded into Epoxy Resin(Epovia, Cray Vally INC) and was cut by buccal to lingual with grinder-polisher unit(Labopol-5, Struers, DK-2750 Bailerup, Denmark) and sandpaper coated with aluminium oxide(resin coated cloth aluminium oxide flex, Korea). After polished, it observed with stereomicroscope (Carl Zeiss, DE/Stemi SV11, Thornwood, NY, USA) equipped with a disital Olympus DP 10camera(Olympus. JP/DP 10-PRN, Japan) for evaluating marginal and internal fit between prosthodontic coping and abutment. The result is as followed;

1. The mean value of AMD(Absolute marginal discrepancy) in Group 1, Group 2, Group 3 are 141.21±42.94μm, 140.63±31.64μm, 109.37±28.42μm. The averages of MG(Marginal gap) in Group 1, Group 2, Group 3 are 82.52±43.99μm, 90.28±27.93μm, 66.55±28.77μm. Statistically there is no difference in AMD and MG among the 3 Groups(Anova, P>0.05).

2. The averages of GA(Gap of axial) in Group 1, Group 2, Group 3 are 133.04±48.60μm, 88.08±25.44μm, 136.3±47.76μm. There is statistically difference among three groups(Anova, P<0.05). The GA of Group 2 is statistically lower than that of the others(Turkey test, P<0.05)

3. The averages of GL(Gap of line angle) in Group1, Group2, Group3 are 238.39±103.14μm, 108.33±27.76μm, 123.82±30.95μm. The averages of GO(Gap of occlusal) in Group 1, Group 2, Group 3 are 276.48±69.12μm, 10476±27.00μm, 98.23±28.71μm.

4. There are statistically significant differences in both GL and GO(Kruskal Wallis Test, P<0.05) among the groups. The GL and GO of Group 1 are statistically significantly different with the others (Mann-whitney test(P<0.05).

Zirconia copings made by 3 ways of scanning methods have no difference with conventional ceramics in AMD and MG which are known as the most important factors. As the result of this study, we conclude that intraoral scanning could be used clinically.