High strength substructure reinforcement for crowns and bridges

Abstract

A reinforcement for a dental restoration substructure is provided. The reinforcement is a generally annular structure that protrudes from the body of the substructure generally near an occlusal portion of the restoration. The annular structure provides a support for veneering porcelain at the location of the greatest thickness of the porcelain and at the location where occlusal stress is applied, and fractures of veneering porcelain are commonly experienced.

What is claimed is: 
     
         1 . A method of making a substructure for a dental restoration, said method comprising the steps of:
 selecting a body shape for the substructure; and   locating a support structure shape on the body for supporting an outer layer;   wherein in said locating step said support structure is purposefully placed and rationalized with the general structure and form of the body to provide support for an outer layer to be formed over and contacting an outer surface of said body and said support structure, and   wherein said support structure is located in a manner to reduce the shear stress exerted on the outer layer.   
     
     
         2 . The method as claimed in  claim 1  wherein said support structure is generally near an occlusal portion of the restoration. 
     
     
         3 . The method as claimed in  claim 1  wherein said support structure is generally near a location in which a generally greatest thickness of veneering material is located. 
     
     
         4 . The method as claimed in  claim 1  wherein said selecting and locating steps are carried out through the use of a software application. 
     
     
         5 . The method as claimed in  claim 4  wherein said software application is a CAD-CAM application. 
     
     
         6 . The method as claimed in  claim 4  wherein said selecting step includes selecting said shape of said support structure from a library of shapes. 
     
     
         7 . The method as claimed in  claim 4  wherein said locating step further comprises the steps of:
 identifying an outer contour shape for the body; and 
 conforming generally at least a portion of the support shape to the outer contour shape. 
 
     
     
         8 . The method as claimed in  7  wherein said identifying and conforming steps are accomplished generally automatically by said software application. 
     
     
         9 . The method as claimed in  claim 4  wherein said step of locating said support structure shape is accomplished simultaneously with said step of selecting a body shape. 
     
     
         10 . The method as claimed in  claim 4  wherein said steps of selecting a body shape and locating a support structure shape are accomplished by removing portions from a final desired shape for the restoration. 
     
     
         11 . The method as claimed in  claim 1  further comprising the step of milling the substructure. 
     
     
         12 . The method as claimed in  claim 1  wherein said milling step is performed after said selecting and locating steps. 
     
     
         13 . The method as claimed in  claim 11  wherein a material from which the substructure is milled includes a body shape and protrusion shape. 
     
     
         14 . The method as claimed in  claim 23  wherein said support structure is located generally proximate to a location of greatest occlusal stress. 
     
     
         15 . A computer implemented system for designing a substructure body for a dental restoration comprising:
 a user input for selecting a body shape for the substructure from a library; and   a tool for locating a support structure shape on the body for supporting a veneer;   wherein said support structure is purposefully placed and rationalized with the general structure and form of the body through said tool to provide support for an outer layer to be formed over and contacting an outer surface of said body and said support structure, and   wherein said support structure is located through said tool in a manner to reduce the shear stress exerted on the outer layer.   
     
     
         16 . The system as claimed in  claim 15  wherein said tool comprises a library of pre-made shapes for said support structure. 
     
     
         17 . The system as claimed in  claim 16  wherein said tool allows a user to manually select a shape from said library for location on said support structure. 
     
     
         18 . The system as claimed in  claim 17  wherein said tool allows the user to manipulate said shape from said library. 
     
     
         19 . The system as claimed in  claim 16  wherein said tool primarily automatically selects a shape from said library for location on said support structure. 
     
     
         20 . The system as claimed in  claim 19  wherein said tool allows a user to manipulate said shape from said library. 
     
     
         21 . The system as claimed in  claim 15  wherein said body shape selected from the library includes a support structure pre-designed into said body shape. 
     
     
         22 . The system as claimed in  claim 21  wherein said tool allows a user to manipulate said support structure shape. 
     
     
         23 . The system as claimed in  claim 15  wherein said support structure is located generally proximate to a location of greatest occlusal stress. 
     
     
         24 . A system for designing a dental restoration comprising:
 an input for referencing a body shape for the restoration; and   a tool for locating a support structure shape on the body;   wherein said support structure is purposefully placed and rationalized with the general structure and form of said body through said tool at a location to purposefully optimize the restoration.   
     
     
         25 . The system as claimed in  claim 24  wherein the body shape is selected from a library via said input. 
     
     
         26 . The system as claimed in  claim 24  wherein said support structure is located generally to optimize strength, durability and/or appearance of the restoration.