Dr. Dennis FasbinderSARAH MUSFER SALEH ALGHAMDI2022-06-022022-06-02https://drepo.sdl.edu.sa/handle/20.500.14154/62401Objective: The aim of this in vitro study was to investigate the translucency of current chairside CAD/CAM materials, in terms of material type and thickness. Materials & Methods: Groups of 12 samples of each material (n=432) were sectioned into four thicknesses (0.5, 1.0, 1.5, and 2.0 mm). The materials were: IPS e.max CAD (Ivoclar Vivadent), Katana STML (Kuraray Noritake), 3M Chairside Zirconia (3M ESPE), IPS Empress CAD (Ivoclar Vivadent), CEREC Tessera (Dentsply Sirona), and Celtra Due CAD (Dentsply Sirona). A digital spectrophotometer (VITA Easy shade) was used to measure the TP. Data were analyzed by one-way ANOVA and the Tukey multiple comparisons test. Results: Higher TP value corresponds to materials with higher translucency, whereas lower TP value corresponds to more opaque materials. TP values ranged from 32.52 (IPS E.max CAD MT at 0.5 mm) to 5.96 (3M Chairside Zirconia at 2.0 mm). All TP values decrease as the thickness of the material increase. One-way ANOVA for translucency parameter revealed a highly significant p-value (p ≤ 0.05) for the interaction between ceramic materials and thickness and a statistically significant difference in mean translucency parameter (TP) among various ceramic materials with similar thicknesses. Statistically significant difference was found in translucency values among various CAD/CAM ceramic materials irrespective of the thickness, and statistically significant difference was found in translucency values among various CAD/CAM ceramic materials with similar thicknesses (p ≤ 0.05) . Conclusions: Translucency and esthetic considerations, as well as the thickness of the restoration, is critical in material selection. As most glass ceramics have similar translucency in thin layers, material selection is case dependent, based on mechanical characteristics of the materials.en