Apparatus And Methods For Visual Demonstration Of Dental Erosion On Simulated Dental Materials

Abstract

Comparative effectiveness of various oral care products such as dentifrices on preventing dental erosion may be demonstrated using simulated enamel. A substrate is prepared. A mineral layer to simulate dental enamel is nucleated by solution growth on the substrate surface. Alternatively, the mineral layer may be nucleated on a template comprising a self-assembled monolayer formed on a gold layer deposited on the substrate surface. The mineral layer may comprise a homogeneous layer of hydroxyapatite or a thin veneer of hydroxyapatite on a layer of amorphous calcium phosphate. The simulated enamel is then optionally treated with an oral care product and subjected to an acid challenge. The amount of mineral layer remaining after the acid challenge illustrates the effectiveness or non-effectiveness of the oral care product at preventing dental erosion.

What is claimed is: 
     
         1 . A demonstration model comprising:
 a. a substrate;   b. a simulated dental enamel layer disposed over the substrate, wherein the simulated dental enamel layer comprises substantially homogeneous hydroxyapatite and wherein the simulated dental enamel layer is less than 100 nm thick;
 wherein the demonstration model provides a visual demonstration of dental erosion; 
 and wherein the demonstration model has physical and chemical properties substantially similar to those of enamel layers of human teeth. 
   
     
     
         2 . The demonstration model of  claim 1 , wherein the substrate is selected from the group consisting of molded polymer articles, polymer films, polymer tapes, silica, quartz, glasses, and combinations thereof. 
     
     
         3 . The demonstration model of  claim 2  wherein the substrate comprises silica. 
     
     
         4 . The demonstration model of  claim 1 , wherein the simulated dental enamel layer has a thickness of from about 10 Å to about 50 μm. 
     
     
         5 . The demonstration model of  claim 1  wherein the simulated dental enamel layer is from about 10 Å to about 10 nm thick. 
     
     
         6 . The demonstration model of  claim 1  wherein the substrate further comprises a metal layer disposed over the substrate comprising gold or an alloy thereof and a self-assembled monolayer comprising a thiol compound disposed on the layer of metal opposite the substrate. 
     
     
         7 . The demonstration model of  claim 6  wherein the thiol compound comprises a carboxylated thiol compound. 
     
     
         8 . The demonstration model of  claim 6  wherein the metal layer has a thickness from about 10 Å to about 1000 Å. 
     
     
         9 . The demonstration model of  claim 6  wherein the metal layer has a charged surface. 
     
     
         10 . The demonstration model of  claim 1  wherein the simulated dental enamel layer further comprises one or more coloring agents wherein the one or more coloring agents enhance the visual contrast between the simulated dental enamel layer and the substrate. 
     
     
         11 . The demonstration model of  claim 1 , wherein the simulated dental enamel layer is a veneer layer of hydroxyapatite. 
     
     
         12 . The demonstration model of  claim 11  wherein the simulated dental enamel layer further comprises an amorphous calcium phosphate layer interposed between the veneer layer of hydroxyapatite and the substrate. 
     
     
         13 . The demonstration model of  claim 12  wherein the amorphous calcium phosphate layer has a thickness of from about 10 Å to about 500 μm. 
     
     
         14 . A demonstration model comprising:
 a. a substrate;   b. a simulated dental enamel layer disposed over the substrate, wherein the simulated dental enamel layer comprises a mineral selected from the group consisting of hydroxyapatite, fluoridated hydroxyapatite, fluorapatite, chlorapatite, and combinations thereof and wherein the simulated dental enamel layer is less than 100 nm thick;
 wherein the demonstration model provides a visual demonstration of dental erosion; 
 and wherein the demonstration model has physical and chemical properties substantially similar to those of enamel layers of human teeth. 
   
     
     
         15 . The demonstration model of  claim 14  further comprising an amorphous calcium layer interposed between the substrate and the simulated dental enamel layer. 
     
     
         16 . The demonstration model of  claim 15  wherein at least one of the amorphous calcium phosphate layer and the simulated dental enamel layer further comprises at least on coloring agent. 
     
     
         17 . The demonstration model of  claim 15  wherein the amorphous calcium phosphate layer comprises a gradated structure comprising a plurality of colored layers, each of the colored layers comprising at least one coloring agent and having a shade or hue different from the other colored layers.