Process for producing dental devices

Abstract

A process for producing dental devices such as teeth is disclosed. Specifically, a process for producing gold dental devices, such as gold denture teeth, is disclosed. The process includes the production of an injection mold based on an impression or mold of a target tooth. The injection mold can then be utilized to produce a hardened polymeric precursor of the product device. In particular, a hardened precursor can be produced from pure polypropylene. The precursor can be used as a model to produce an investment casting mold. The desired product material, for example a gold alloy, can then be cast in the investment casting mold by methods known in the art to produce the final product.

What is claimed is:  
     
         1 . A process for producing a hardened polymeric precursor of a dental device comprising: 
 creating an injection mold, said injection mold defining a cavity of the shape of a dental device, said cavity having at least one wall, said injection mold comprising an insert, said insert being located within said cavity so as to maintain a gap between at least a portion of said insert and said wall of said cavity;    injecting a molten polymeric material into said injection mold, said polymeric material substantially filling said gap; and    setting said molten polymeric material to form a hardened polymeric precursor of said dental device.    
     
     
         2 . The process as defined in  claim 1  further comprising producing an investment casting mold from said hardened polymeric precursor.  
     
     
         3 . The process as defined in  claim 2  further comprising removing said hardened polymeric precursor from said investment casting mold.  
     
     
         4 . The process as defined in  claim 3  further comprising casting a metallic material in said investment casting mold to form said dental device.  
     
     
         5 . The process as defined in  claim 1 , wherein said polymeric material comprises a thermoplastic material.  
     
     
         6 . The process as defined in  claim 1 , wherein said polymeric material comprises a polyolefin.  
     
     
         7 . The process as defined in  claim 5 , wherein said thermoplastic material is selected from the group consisting of polypropylene, polyethylene, and copolymers thereof.  
     
     
         8 . The process as defined in  claim 1 , wherein said dental device comprises a crown for a tooth.  
     
     
         9 . The process as defined in  claim 1 , wherein said dental device comprises a tooth.  
     
     
         10 . The process as defined in  claim 4 , wherein said metallic material comprises a precious metal.  
     
     
         11 . The process as defined in  claim 10 , wherein said precious metal comprises a gold alloy.  
     
     
         12 . The process as defined in  claim 11 , wherein said gold alloy is selected from the group consisting of 22 karat yellow gold, white gold, and coin gold.  
     
     
         13 . The process as defined in  claim 3 , wherein said thermoplastic precursor is removed from said investment casting mold at a temperature of about 1200° F. to about 1300° F.  
     
     
         14 . The process as defined in  claim 11 , wherein said dental device comprises a wall, said wall having a thickness of from about 0.0010 to about 0.0011 inches.  
     
     
         15 . The process as defined in  claim 1 , wherein said injection mold defines more than one said cavity.  
     
     
         16 . The process as defined in  claim 2 , wherein said investment cast comprises more than one said hardened polymeric precursor.  
     
     
         17 . A process for producing a unitary tooth comprising: 
 creating an injection mold, said injection mold defining a cavity of the shape of said unitary tooth, said cavity having at least one wall, said injection mold comprising an insert, said insert being located within said cavity so as to maintain a gap between at least a portion of said insert and said wall of said cavity;    injecting a thermoplastic material into said injection mold, said thermoplastic material substantially filling said gap;    setting said thermoplastic material to form a hardened thermoplastic precursor of said unitary tooth;    producing an investment casting mold from said hardened thermoplastic precursor;    removing said hardened thermoplastic precursor from said investment casting mold; and    casting a gold alloy in said investment casting mold to form said unitary tooth.    
     
     
         18 . The process as defined in  claim 17 , wherein said unitary tooth comprises a wall, said wall comprising a wall thickness of from about 0.0010 to about 0.0011 inches.  
     
     
         19 . The process as defined in  claim 17 , wherein said thermoplastic material comprises a polyolefin.  
     
     
         20 . The process as defined in  claim 17 , wherein said thermoplastic material is selected from the group consisting of polypropylene, polyethylene, and copolymers thereof.  
     
     
         21 . The process as defined in  claim 17 , wherein said gold alloy is selected from a group consisting of 22 karat yellow gold, white gold, and coin gold.  
     
     
         22 . The process as defined in  claim 17 , wherein said hardened thermoplastic precursor is removed from said investment casting mold at a temperature of about 1200° F. to about 1300° F.  
     
     
         23 . The process as defined in  claim 17 , wherein said injection mold defines more than one said cavity.  
     
     
         24 . The process as defined in  claim 17 , wherein said investment cast comprises more than one said hardened thermoplastic precursor.  
     
     
         25 . A process for producing a unitary tooth comprising: 
 producing an investment casting mold from an injection molded precursor;    removing said injection molded precursor from said investment casting mold; and    casting a metallic material in said investment casting mold to form said unitary tooth.    
     
     
         26 . The process as defined in  claim 25  wherein said injection molded precursor comprises a polyolefin.  
     
     
         27 . The process as defined in  claim 25  wherein said injection molded precursor is of a material selected from the group consisting of polypropylene, polyethylene, and copolymers thereof.  
     
     
         28 . The process as defined in  claim 25  wherein said injection molded precursor is removed out from said investment casting mold at a temperature of about 1200° F. to about 1300° F.  
     
     
         29 . The process as defined in  claim 25 , wherein said metallic material comprises a precious metal.  
     
     
         30 . The process as defined in  claim 29 , wherein said precious metal comprises a gold alloy.  
     
     
         31 . The process as defined in claim  30 , wherein said gold alloy is selected from the group consisting of 22 karat yellow gold, white gold, and coin gold.  
     
     
         32 . The process as defined in  claim 25 , wherein said investment cast comprises more than one said injection molded precursor.