Patent ID: 7210932

Claim:
A method for making a dental prostheses model cast including a base and a cast of teeth made from an impression mold having formed therein imprints of a patient's teeth, said method comprising; a. pouring liquid die stone into a shallow upper depression in a molding tray having, i. a body having therewithin an interior space enclosed by an inner longitudinally disposed surface of a peripheral wall disposed between an upper transverse face and a lower transverse face, ii. a base wall located within said interior space of said body, said base wall having an upper surface recessed inwardly to a first, upper recess depth inwardly of said upper transverse face and forming within said interior space a first, downwardly concave shallow upper depression, said base wall having a lower surface recessed inwardly a second, larger recess depth inwardly of said lower transverse face, and forming a second, upwardly concave lower depression which is deeper than said upper depression, said base wall having formed therein a central panel breakable away from an outer ring-shaped portion of said base wall to form therethrough an aperture which communicates between said upper and lower depressions, iii. a plurality of spaced apart projections which protrude inwardly form inner surfaces of opposed inner sides of said peripheral wall, said projections alternating with spaces formed between said projections, iv. said shallow upper depression being adapted to receive liquid die stone therein to thereby harden to comprise a base of a dental model cast fused with a cast of teeth made in an impression mold, said central panel of said base wall adapted to being broken away from said outer ring-shaped portion of said base wall, and enabling said cast to be ejected upwardly out from said tray, pins installed on a lower surface of said cast base, said cast base being re-insertable into said shallow upper depression to a predetermined index position within said tray determined by engagement of said alternating projections and spaces of said tray with complementary-shaped spaces and projections molded into sides of said cast, said recess depth of said lower depression being greater than extension length of said pins below said cast, a. allowing time for said liquid die stone to harden, b. breaking said central panel away from said outer ring-shaped portion of said base wall, c. ejecting said cast base upwardly from said tray, and e. installing pins protruding downwardly from a lower face of said cast base.