Title Page
Contents
Abstract 7
I. Introduction 9
II. Materials & Methods 13
A. Test specimen preparation 13
B. Translucency 15
1. Color measurement 15
2. Translucency parameter (TP) calculation 16
C. Masking ability 16
1. Background material preparation 16
2. Color measurement 17
3. Color difference (ΔE) calculation 17
D. Statistical analysis 18
III. Results 19
A. Translucency parameter (TP) 19
B. Masking ability. 22
IV. Discussion 25
V. Conclusion 32
References 33
국문초록 39
Table 1. CAD-CAM materials used in this study. 3Y-TZP (3 mol% yttria tetragonal zirconia polycrystals), 4Y-PSZ (4 mol% yttria partially stabilized zirconia), 5.5Y-PSZ... 14
Table 2. Average TP (translucency parameter) values and standard deviations for each specimen. 20
Table 3. Mean ΔE values and standard deviations for each specimen. Under the same conditions, the same superscription indicates that there is no statistical difference in... 23
Fig. 1. A, Spectrophotometer (SpectroShade Micro, MHT Optic Research, AG) used in this study. B, CIELAB value was measured with a spectrophotometer. 15
Fig. 2. Background materials for masking ability test. 17
Fig. 3. Graphs showing the mean translucency parameter (TP) values. 20
Fig. 4. Specimens of zirconias and lithium disilicate on black and white backgrounds. 21
Fig. 5. The mean ΔE values of 0.8 mm specimens on each backgrounds. Acceptability threshold (5.5) and perceptibility threshold (2.6) are shown on the graph. 24
Fig. 6. The mean ΔE values of 1.5 mm specimens on each backgrounds. Acceptability threshold (5.5) and perceptibility threshold (2.6) are shown on the graph. 24