Dental tray and articulator

I claim the improvement in a tray used in the dental art for forming a dental model in which said tray is made entirely of a polymeric material and has a substantially planar base, a back wall and a circuitous side wall, with said back wall and said side wall extending upwardly substantially perpendicular to a broad upper face of said planar base so as to form a cavity having an open top facing upwardly from said planar base, whereby dental casting material is poured into said cavity in forming said dental model, said improvement in said tray comprising

• providing a substantially planar, narrow flange integrally attached to an upper edge of said circuitous side wall so as to extend outwardly substantially perpendicular from said upper edge of said circuitous side wall and wherein a pair of spaced apart, substantially flat, ears extend outwardly from said flange at a front end portion of said tray, with said ears being formed integrally with said flange such that said ears form flat, coplanar projections extending outwardly from said flange.