Aim of the study: This study was designed to evaluate the effect of (a) grinding (b) sandblasting and (c) ageing on the flexural strength of Translucent and Conventional biomedical grade Y-TZP ceramics. Material and methods: A total of twenty bars (L=32 ± 0.2 × W=4± 0.2 × H=3±0.1mm) of partially sintered blocks, Translucent (Prettua) and Conventional (Ice Translucent) Zirconia ten of each. Bars were prepared using Zirkonzhan CAD/CAM strategy the dimensions of the specimens followed ISO standard. In this study the two groups of Zirconia were farther subdivided into two groups according to the type of surface treatment applied to them. Group A: Prettua Zirconia bars .Group B: Ice Translucent Zirconia bars. The two groups were farther subdivided into two subgroups. Subgroups A1 and B1: Undergone sandblasting the specimens were mounted on a custom made apparatus to standardize the sandblasting procedure a distance of 10mm from the nozzle to the specimen The alumina abrasion regime was carried out using alumina powder with a 50 μm particle size, for 10s at 2 bar pressure. Subgroup A2 and B2: were ground on the top surface with a coarse-grit diamond bur (150μm) by finger pressure by the same individual in order to simulate clinical conditions, the grinding speed was 150000 rpm for 6 sec by moving the hand piece back and forth. The Accelerated aging experiments were conducted in an autoclave at 134 ˚C for 2 h. The samples were stored for 24h at 37◦C in an incubator with artificial saliva solution before final testing was conducted. All samples were individually mounted in a costume made three point bend test machine. Then the samples were statically compression loaded until fracture at a crosshead speed of 1mm/min. Results: Statistically there was no significant difference between mean flexural strength of the two ceramics. Sandblasting showed statistically significantly higher mean flexural strength than grinding. Conclusion: Sandblasting resulted in higher flexural strength due to the formation of a compressive layer. Flaws caused by sandblasting didn’t seem to exceed this layer. Grinding caused degradation of the flexural strength due to radial cracks that extended from the grinding grooves into the bulk.