Background: Treatment challenges for completely edentulous patient have traditionally been described as a combination of esthetics, function and comfort. Some studies regarding complete denture esthetics were more important than function or comfort. Denture characterization is modification of the form of the denture base to produce a more natural appearance. Materials and Methods: Acrylic resin complete dentures had been divided into two groups according to flasking technique (group I as control group: conventional three pour flasking technique, group II as test group: silicone mask flasking technique). ΔE was calculated for both groups immediately and after seven days of exposure to different staining conditions (Smoke, Coffee and Tea). Results: Heat cured acrylic resin complete denture processed through silicone mask flasking technique showed statistically significant lower ΔE values (as P < 0.05) than conventionally processed heat cured acrylic resin complete denture. Conclusion: With the limitations of this study regarding color stability change (ΔE), depending on flasking technique; the conventional three pour flasking technique showed a higher amount of color change (lower color stability) than the silicone mask flasking technique regarding smoking, tea and coffee coloring agents.