Dental cast tray assembly

A dental cast tray assembly used to form a dental cast model comprises a base and a tray removably mounted on the base. The base includes a top surface which is recessed to form a support surface and a pair of restriction walls which protrude up from the support surface, each restriction wall including a plurality of surface irregularities. The base also includes an elongated, tubular projection which extends nearly the entire length of the base. The projection includes a rounded top, a pair of inwardly curved sidewalls and an elongated slot. The tray includes an elongated socket which includes a pair of thin fingers that are capable of flexion. The socket defines an opening into which the projection is capable of being releasably press-fit. The tray is notched to form first and second outer restriction walls, each outer restriction wall including a plurality of surface irregularities which are sized and shaped to engage the surface irregularities formed on the base.