Dental mill blanks

Abstract

A dental mill blank comprising a resin and a filler, wherein the blank is fabricated such that it passes a Thermal Shock Test. The mill blank is substantially free of cracks and discontinuities. Further, the blank may have superior cuttability and hardness.

We claim:  
     
         1 . A carvable mill blank for making a dental prosthetic comprising 
 a) a polymeric resin and    b) a filler,    wherein the blank is substantially free of cracks and fabricated such that the blank passes a Thermal Shock Test.    
     
     
         2 . The blank of  claim 1  wherein the blank is substantially free of discontinuities in the material that are larger than about 1 millimeter.  
     
     
         3 . The blank of  claim 1  wherein the blank is substantially free of discontinuities in the material that are larger than about 0.1 millimeter.  
     
     
         4 . The blank of  claim 1  wherein the blank is substantially free of discontinuities in the material that are larger than about 0.01 millimeter.  
     
     
         5 . The blank of  claim 1  wherein the blank further comprises a fluoride releasing material.  
     
     
         6 . The blank of  claim 1  wherein the polymeric resin is made from a material comprising a free radically curable monomer, oligomer or polymer.  
     
     
         7 . The blank of  claim 1  wherein the polymeric resin is made from a material comprising a cationically curable monomer, oligomer or polymer.  
     
     
         8 . The blank of  claim 1  wherein the polymeric resin is made from a material comprising a free radically curable monomer, oligomer or polymer and cationically curable monomer, oligomer or polymer.  
     
     
         9 . The blank of  claim 6  wherein the material is selected from the group consisting of 2,2-bis[4-(2-hydroxy-3-methacryloyloxypropoxy)phenyl]propane (bisGMA), triethyleneglycol dimethacrylate (TEGDMA), 2,2-bis[4-(2-methacryloyloxyethoxy)-phenyl]propane (bisEMA), 2-hydroxy ethyl methacrylate (HEMA), urethane dimethacrylate (UDMA) and any combinations thereof.  
     
     
         10 . The blank of  claim 7  wherein the material is selected from the group consisting of diglycidyl ether of bisphenol A, 3,4-epoxycyclohexylmethyl-3-4-epoxy cyclohexene carboxylate, bisphenol F epoxides, and polytetrahydrofuran.  
     
     
         11 . The blank of  claim 1  wherein the resin is made from a material comprising a monomer, oligomer or polymer comprising both a free radically curable functionality and a cationically curable functionality.  
     
     
         12 . The blank of  claim 1  wherein the filler is selected from the group consisting of barium glass, quartz and zirconia silica.  
     
     
         13 . The blank of  claim 1  wherein the filler is derived from a sol-gel process.  
     
     
         14 . The blank of  claim 1  wherein the blank is capable of being further hardened after or during milling by a curing process.  
     
     
         15 . A carvable mill blank for making a dental prosthetic comprising 
 a) a resin component and    b) a fluoride releasing component.    
     
     
         16 . A method of making the dental mill blank of  claim 1  comprising the steps of 
 a) mixing a paste comprising a resin and a filler,  
 b) shaping the paste into a desired configuration,  
 c) minimizing material discontinuities from the paste  
 d) curing the paste into a blank, and  
 e) relieving internal stresses in the blank.  
 
     
     
         17 . The method in  claim 16  wherein shaping the paste is performed using a mold and further comprising the steps of 
 f) trimming excess paste material from the mold, and  
 g) removing the cured paste from the mold.  
 
     
     
         18 . The method in  claim 16  further comprising the step of 
 f) mounting a handle to the cured paste.  
 
     
     
         19 . The method in  claim 16  wherein the curing system is selected from the group consisting of heat, light, microwave, e-beam and chemical cure.  
     
     
         20 . The method in  claim 16  wherein the stress relieving step comprises slowly heating the cured paste in an oven temperature of at or above Tg of the resin.  
     
     
         21 . A method of making the dental mill blank of  claim 1  comprising the steps of 
 a) mixing a paste comprising a resin and a filler,  
 b) shaping the paste into a desired configuration,  
 c) minimizing material discontinuities from the paste  
 d) slow curing the paste on a light box for a sufficient time to effectuate low stress cure, such that the cured paste passes a Thermal Shock Test.  
 
     
     
         22 . A method of making a dental prosthetic comprising the steps of 
 a) mixing a paste comprising a resin and a filler,    b) shaping the paste into a desired blank configuration,    c) minimizing material discontinuities from the paste,    d) curing the paste into a blank,    e) carving the blank into a desired shape and morphology,    wherein the blank is substantially free of cracks and fabricated such that the blank passes a Thermal Shock Test.    
     
     
         23 . The method of  claim 22  further comprising the step of: 
 f) adding additional material to the carved blank.  
 
     
     
         24 . The method of  claim 22  further comprising the step of: 
 f) attaching the carved blank to tooth or bone structure.  
 
     
     
         25 . The method of  claim 22  further comprising the steps of: 
 f) manually changing the morphology of the carved blank and  
 g) finishing the outer surface of the carved blank.  
 
     
     
         26 . The method of  claim 22  wherein an intermediate step between curing and carving the paste comprises attaching a handle to the cured paste and wherein the carving is performed by a milling machine.  
     
     
         27 . The method of  claim 22  wherein the carving step is performed by a hand-held instrument.  
     
     
         28 . The mill blank in  claim 1  wherein the wherein the mill blank has a Barcol Hardness value greater than about 0% of the Barcol Hardness of a Standard Fumed Silica Mill Blank, and a Cuttability value greater than about 30% of the Cuttability value of a Standard Fumed Silica Mill Blank.  
     
     
         29 . The mill blank in  claim 1  wherein the mill blank has a Barcol Hardness value greater than about 5% of the Barcol Hardness of a Standard Fumed Silica Mill Blank.  
     
     
         30 . The mill blank in  claim 1  wherein the mill blank a Barcol Hardness value greater than about 15% of the Barcol Hardness of a Standard Fumed Silica Mill Blank.  
     
     
         31 . The mill blank in  claim 1  wherein the mill blank has a Cuttability value greater than about 50% of the Cuttability of a Standard Fumed Silica Mill Blank.  
     
     
         32 . The mill blank in  claim 1  wherein the mill blank has a Cuttability value greater than about 100% of the Cuttability of a Standard Fumed Silica Mill Blank.  
     
     
         33 . The mill blank in  claim 1  wherein the filler is at least about 50% by weight of the total weight of the mill blank.  
     
     
         34 . The mill blank in  claim 1  wherein the filler is at least about 65% by weight of the total weight of the mill blank.  
     
     
         35 . The mill blank in  claim 1  wherein the filler is at least about 80% by weight of the total weight of the mill blank.