Abstract: The present invention provides methods, processes, and systems for the manufacture of three-dimensional articles of polymer materials using 3D printing. A syringe or an inkjet print head prints a solution of prepolymer onto a build plate. The printed prepolymer is exposed to a stimulus whereby the prepolymer is converted to the polymer. After a predetermined time, sequential layers are printed to provide the three-dimensional article. The three-dimensional article can be cured to produce the 3D article made from the final polymer.

Abstract: The present invention provides methods, processes, and systems for the manufacture of three-dimensional articles of polymer materials using 3D printing. A syringe or an inkjet print head prints a solution of prepolymer onto a build plate. The printed prepolymer is exposed to a stimulus whereby the prepolymer is converted to the polymer. After a predetermined time, sequential layers are printed to provide the three-dimensional article. The three-dimensional article can be cured to produce the 3D article made from the final polymer.

Abstract: The present invention provides methods, processes, and systems for the manufacture of three-dimensional articles made of polymers using 3D printing. A layer of prepolymer is deposited on a build plate to form a powder bed. The deposited powder bed is heated to about 50° C. to about 170° C. Then, a solution of activating agent is printed on the powder bed in a predetermined pattern, and a stimulus is applied converting the prepolymer to the final polymer. After a predetermined period of time, sequential layers are printed to provide the three-dimensional article. The three-dimensional object can be cured to produce the three-dimensional article composed of the final polymers.

Abstract: The present invention provides methods, processes, and systems for the manufacture of three-dimensional articles of polymer materials using 3D printing. A syringe or an inkjet print head prints a solution of prepolymer onto a build plate. The printed prepolymer is exposed to a stimulus whereby the prepolymer is converted to the polymer. After a predetermined time, sequential layers are printed to provide the three-dimensional article. The three-dimensional article can be cured to produce the 3D article made from the final polymer.

Abstract: The present invention provides methods, processes, and systems for the manufacture of three-dimensional articles made of polymers using 3D printing. A layer of prepolymer is deposited on a build plate to form a powder bed. The deposited powder bed is heated to about 50° C. to about 170° C. Then, a solution of activating agent is printed on the powder bed in a predetermined pattern, and a stimulus is applied converting the prepolymer to the final polymer. After a predetermined period of time, sequential layers are printed to provide the three-dimensional article. The three-dimensional object can be cured to produce the three-dimensional article composed of the final polymers.

Abstract: Disclosed herein are artificial teeth that include an enamel portion comprising a thermoset resin and a radio-opaque filler material distributed within the thermoset resin.

Abstract: A method for modeling an object, particularly suited to complex objects such as anatomical objects, and manipulating the modeled object in a CAD environment includes obtaining volumetric scan data of a region and segmenting the scan data to identify a first object to produce a first set of signed distance values on a grid. Wavelet analysis of the first set of signed distance values provides a function-based representation of the object. A signed distance value model of a second object is obtained, and one or both sets of signed distance values are manipulated to perform a CAD operation.

Abstract: The geometry of an object is inferred from values of the signed distance sampled on a uniform grid to efficiently model objects based on data derived from imaging technology that is now ubiquitous in medical diagnostics. Techniques for automated segmentation convert imaging intensity to a signed distance function (SDF), and a voxel structure imposes a uniform sampling grid. Essential properties of the SDF are used to construct upper and lower bounds on the allowed variation in signed distance in 1, 2, and 3 (or more) dimensions. The bounds are combined to produce interval-valued extensions of the SDF, including a tight global extension and more computationally efficient local bounds that provide useful criteria for root exclusion/isolation, enabling modeling of the objects and other applications.

Abstract: A method for modeling an object, particularly suited to complex objects such as anatomical objects, and manipulating the modeled object in a CAD environment includes obtaining volumetric scan data of a region and segmenting the scan data to identify a first object to produce a first set of signed distance values on a grid. Wavelet analysis of the first set of signed distance values provides a function-based representation of the object. A signed distance value model of a second object is obtained, and one or both sets of signed distance values are manipulated to perform a CAD operation.

Abstract: A method is disclosed for the solid modeling of objects that is particularly suitable to modeling objects obtained from scan data, typically voxel-based data, for example medical imaging data. The method provides a more direct approach to providing solid modeling capabilities in modeling complex objects, such as organic objects, that are identified through a segmentation of the scanned data. The voxel-based data is obtained, and segmented to identify in the data the surface of the object. The segmentation is preferably accomplished using a graph cuts/level set method to obtain a grid of signed distance function data. The signed distance function data is then interpolated using wavelets, to produce a functional representation model of the object. The model does not require tessellation, and may be relatively compact. In particular, the resulting wavelet analysis is inherently amenable to multi-resolution analysis and compaction.

Abstract: The geometry of an object is inferred from values of the signed distance sampled on a uniform grid to efficiently model objects based on data derived from imaging technology that is now ubiquitous in medical diagnostics. Techniques for automated segmentation convert imaging intensity to a signed distance function (SDF), and a voxel structure imposes a uniform sampling grid. Essential properties of the SDF are used to construct upper and lower bounds on the allowed variation in signed distance in 1, 2, and 3 (or more) dimensions. The bounds are combined to produce interval-valued extensions of the SDF, including a tight global extension and more computationally efficient local bounds that provide useful criteria for root exclusion/isolation, enabling modeling of the objects and other applications.

Abstract: A method is disclosed for the solid modeling of objects that is particularly suitable to modeling objects obtained from scan data, typically voxel-based data, for example medical imaging data. The method provides a more direct approach to providing solid modeling capabilities in modeling complex objects, such as organic objects, that are identified through a segmentation of the scanned data. The voxel-based data is obtained, and segmented to identify in the data the surface of the object. The segmentation is preferably accomplished using a graph cuts/level set method to obtain a grid of signed distance function data. The signed distance function data is then interpolated using wavelets, to produce a functional representation model of the object. The model does not require tessellation, and may be relatively compact. In particular, the resulting wavelet analysis is inherently amenable to multi-resolution analysis and compaction.

Abstract: A method is disclosed for segmentation of three dimensional image data sets, to obtain digital models of objects identifiable in the image data set. The image data set may be obtained from any convenient source, including medical imaging modalities, geological imaging, industrial imaging, and the like. A graph cuts method is applied to the image data set, and a level set method is then applied to the data using the output from the graph cuts method. The graph cuts process comprises determining location information for the digital data on a 3D graph, and cutting the 3D graph to determine approximate membership information for the object. The boundaries of the object is then refined using the level set method. Finally, a representation of the object volumes can be derived from an output of the level set method. Such representation may be used to generate rapid prototyped physical models of the objects.

Abstract: Starting with a solid model of a 3D object, an accurate skeleton is produced by minimizing internal and edge errors of an initial approximate skeleton. To produce the initial approximate skeleton, the boundary of the solid is densely sampled to obtain a set of surface data points. Delaunay triangulation is performed on the surface data points and exterior and spurious tetrahedra are removed, leaving substantially interior tetrahedra. Circumspheres are constructed that enclose the tetrahedra, and the centers of the circumspheres are connected based on tetrahedra adjacency, to form a Voronoi diagram. Closed Voronoi cells are identified comprising the initial approximate skeleton. The position of skeleton interior vertices are then adjusted to minimize their error, producing a refined polygonal approximation of the skeleton interior geometry. Positions of the skeleton edge vertices are adjusted to minimize the edge error, yielding an accurate polygonal approximation of the skeleton.

Abstract: A solid model is constructed from surface point data that represent layers of an object. The model is represented as the level set of an implicit function that is fitted to the surface point data. In the two-dimensional application of the technique, a Delaunay triangulation is performed for each layer. In this step, surface points are connected to form Delaunay triangles; the data points are the vertices of the Delaunay triangles. A circumcircle is then created around each Delaunay triangle, passing through the three vertices of the triangle. To decimate the circumcircle data, overlapping circumspheres are merged according to a merging criterion. A pseudo-union of implicit functions for the reduced number of circumcircles provides an initial implicit function for the layer. Errors in the implicit function are substantially reduced by optimizing the position and/or radii of the circumcircles.

Abstract: The present invention provides a unified, automated approach to 3D object interpolation and 3D morphing based on a geometric descriptor known as the skeleton. The skeleton of an object consists of the closure of the set of points minimally equidistant from two points on the object's boundary. An "intermediate 3D object" between a pair of two other 3D objects is obtained as the (trimmed) skeleton of the symmetric difference of the pair of objects. By applying this process recursively, any desired number of intermediate 3D objects between a first and a last object may be obtained to produce a discrete 3D morph. A discrete morph can be thought of as an animation starting from the initial object and ending with the final object after a given number of the intermediate objects. Alternatively, the skeleton is used to identify corresponding points on the surfaces of the objects. Interpolation between the location of the corresponding points is then used to determine a continuum of intermediate 3D objects.