Solid free form fabrication techniques such as fused deposition modeling
and three-dimensional printing are used to create a shell or die used in
the manufacture of a dental restoration. Three-dimensional printing
includes ink-jet printing a binder into selected areas of sequentially
deposited layers of powder. Each layer is created by spreading a thin
layer of powder over the surface of a powder bed. Instructions for each
layer may be derived directly from a CAD representation of the
restoration. The area to be printed is obtained by computing the area of
intersection between the desired plane and the CAD representation of the
object. All the layers required for an aesthetically sound shell can be
deposited concurrently slice after slice and sintered/cured
simultaneously.