Dentures and process for making the same

Claim 1

The process for making a denture comprising teeth of hard non-hydrophilic polyurethane elastomer imbedded in soft non-hydrophilic polyurethane elastomer from a model assembly comprising a mouth model having mounted thereon a wax replicate denture, which comprises coating the mouth model and wax replicate denture portions of the model assembly with a release material, and imbedding it in investment material to form a mold having a cavity corresponding to the wax replicate denture, allowing or causing the investment material to set up, removing the mouth model and wax replicate denture therefrom, pouring into the cavity thus formed hard non-hydrophilic polyurethane elastomer-forming material to a depth above the gum line but below the gum-engaging portion of the denture to be formed and allowing or causing it to set up to form a hard non-hydrophilic polyurethane elastomer casting, removing the casting from the mold cavity and trimming off the flash from the anterior and posterior sides of the casting down to the gum line to delineate the shape of that portion of the teeth to be imbedded in the gum portion of the denture, removing the wax replicate denture from the mouth model, coating with release material the portion of the mouth model exposed by the removal of the wax replicate denture, assembling the mouth model and the female mold to form a denture mold, introducing thereinto soft non-hydrophilic polyurethane-forming material and allowing or causing the same to set up therein to form soft non-hydrophilic polyurethane elastomer and to chemically unite with the portions of the hard non-hydrophilic polyurethane elastomer teeth with which it is in contact, removing the cast denture from the mold and finishing them as needed.