Here's a simple example, where there are built-in functions to describe both objects.
{shell, ball} = DiscretizeGraphics /@ {Sphere[], Ball[]}
The first of these is a 2D region embedded in 3D, the other is a 3D region.
RegionDimension /@ {shell, ball}
RegionEmbeddingDimension /@ {shell, ball}
Area /@ {shell, ball}
Volume /@ {shell, ball}
(* {2, 3} *)
(* {3, 3} *)
(* {12.5066, ∞} *)
(* {0, 4.15297} *)
Show[#, PlotRange -> {{0, 1}, {0, 1}, {0, 1}}] & /@ {shell, ball}
Is there any method to essentially convert the shell into the ball? In practice, the shell would come from discretizing a Plot3D or some other type of method, and I want to create a filled object from that shell


TriangulateMesh@BoundaryDiscretizeGraphics@Sphere[]is the answer. Thanks! – Jason B. Apr 13 '16 at 08:22