Background: Yttrium stabilized zirconia a ceramic material currently considered as an “aesthetic” alternative in fixed partial denture. Clinical studies they have shown micro fractures in the area of the connectors, detachment or “chipping” ceramic coating and also the difficulties in fitting for her cementing. Objective: To establish the influence of sandblasting on flexural strength and fracture toughness of two Yttrium stabilized zirconia with two cross- sectional areas. Material and methods: Two materials were tested VITA Inceram YZ and IPS e.max ZirCAD, for each material was obtained 20 bars of 25mm in length, 2x2mm±0.02 width and height and 20 bars of 3x3mm±0.03 width and height. The samples were sintered; ten samples of each group were subjected to surface treatment with sandblasting. Each specimen was loaded to fracture in a Universal Testing Machine with a transverse head speed of 1±0.5mm/min. The data were analysed with the t student test . Results: The zirconia e.max ZirCAD has the highest flexural strength (1232.78 MPa) and the load-bearing fracture (802.74N). Surface treatment VITA Inceram YZ had a higher flexural strength (906.85 MPa) and supported a major load 565,55N. The test t student indicated statistically significant differences in the group IPS e.max ZirCAD when it is sandblasting, so much in the resistance to the flexion, since in the maximum load up to the fracture in both areas. There were no statistically significant differences between two ceramics, it having considered both cross-section areas and surface treatment (with and without sandblasting). Conclusions: Sandblasting, the values flexural strength and fracture toughness of the two ceramics in the two areas of cross section significantly decreasing.