Abstract: A disposable plunger for use in a pressing furnace for the fabrication of dental restorations. The plunger is fabricated of a refractory investment material such as gypsum-bonded, phosphate-bonded or ethyl silicate-bonded investment materials. The plunger is fabricated by known casting methods. The mold used for making the plunger can be supplied by a manufacturer of molds or can be easily made by using an alumina or similar plunger as a model. Laborious cleaning and grinding are not required with plungers herein described. Cracking problems that occur with prior art plungers are decreased, if not completely eliminated.