Vacuum mixers combine gypsum stone, investment powder, or other dental materials with liquid under vacuum, removing entrapped air during mixing to produce a homogeneous, bubble-free mix before pouring models or investing casting patterns. Air-free mixing improves the accuracy and strength of poured models and reduces porosity-related casting defects in investment materials, both of which affect the precision of downstream design and fabrication steps. Vacuum mixers are standard equipment at the model-pouring and investing stages of conventional laboratory workflows, supporting consistent material quality across a laboratory's daily case volume.