Purpose: To evaluate the internal adaptation of full contour zirconia crowns to veneered zirconia with two different finish line designs (shoulder and deep chamfer). Materials and Methods: Twenty four dies were received twelve full contour zirconia crowns (Prettau) and twelve veneered zirconia crowns (ICE Zirconia). Each group will be subdivided into two equally subgroups: with Shoulder finish line and with Deep chamfer finish line. Measurements of internal fitness were recorded Results: The lowest overall mean value of internal adaptation was recorded with Ice zirconia crowns with deep chamfer finish line design (74.6µm ± 19.14), then with shoulder finish line design (93.40 µm ± 9.99), followed by Prettau zirconia crowns with deep chamfer finish line design (157µm ± 27.25) and finally Prettau zirconia crowns with shoulder finish line design (181µm ± 24.86). Conclusions: The ice zirconia crowns recorded better overall internal adaptation values than Prettau crowns with both finish line designs.