Device for mixing two pasty materials, especially for mixing a dental impression material with a catalyst material

A device for mixing two pasty substances comprising housing (42) including a substantially tubular section (44), said substantially tubular section (44) having two inlet openings (68, 70), each for receiving a pasty substance at a rear end (48) of the housing (42) and an outlet opening (52) for discharging an admixed pasty substance from a front end of the tubular section (44), a rotatable mixer shaft (38) extending into the tubular section (44) and being rotatably supported in the housing (42), the mixer shaft (38) including a plurality of rigid mixer elements (74) protruding from an axis (72) thereof for admixing the two pasty substances during their passage through the tubular section (44), an annular insertion part (62) within the rear end (48) of the housing (42) disposed substantially concentric to the axis (72), the insertion part (62) including an inner surface facing the tubular section (44) of the housing (42) and an outer surface forming the rear end (48) of the housing (42), said rear end (48) of the housing (42) having two inlet stubs (54, 56), said mixer shaft (38) including a mixer shaft portion adjacent the inlet openings (68, 70) carrying at least one deflection element (80) for deflecting the pasty substances fed through the inlet openings (68, 70) substantially axially into the tubular section (44) of the housing (42), said at least one deflection element (80) including a deflection surface (82) extending about the axis (72) and at an inclination to a radial plane thereof, the insertion part (62) being provided with a cylindrical recess (69) housing said mixer shaft portion and the at least one deflection element (80), two ducts (64, 66) extending from said two inlet stubs (54, 56) to said inlet openings (68, 70), and said two ducts (64, 66) open substantially radially into said cylindrical recess (69).