PURPOSE: To prepare a model for orthodontics having one and the same standard and an excellent aesthetic impression, in a short time by preparing two parallel panels, a parelleling unit composed of three support columns for supporting the two panels, a die frame for determining a size of the model, a protractor for setting the model at an angle, and a protractor holding board for supporting the protractor.

CONSTITUTION: In the case of preparing orthodontics diagnostic models (upper and lower jaws), a standard die frame is at first made of acrylic resin, epoxy resin or the like. Further, a paralleling unit is composed of a flexible upper panel 16, rods 17 and a panel 18 having an upper surface on which the die frame is set. Plaster slurry having been vacuum-kneaded is filled in the die frame, and the lower jaw model is sunk into the plaster slurry, after solidification of the plaster slurry, the model is removed from the die frame so as to obtain a mirror-finished lower jaw model 3. Further, the upper jaw model 1 is prepared by a method similar to the above method by meshing the upper and lower models together and by attaching a thing meshed with the panel 16. Thereafter, the upper and lower models are ground so as to obtain final products.