Yes there is. And when you say 3D extrusion object, I assume you have Photoshop CSx Extended and want to use Photoshop's 3D tools to do the job. Alright, I'll list the steps you'll want to take as best as I can.
1. Make a new blank layer and name it sphere, open the 3D panel (Window>3D) and from the "Create New 3D Object" menu, select 3D Shape from Preset, then select "Sphere" from the dropdown menu. A 3D sphere will appear on the layer.
2. Make another blank layer and name it pyramid, and from the same panel, select Pyramid from the dropdown menu. You should now have a 3D sphere and Pyramid on the screen.
3. On the pyramid layer, from the 3D tools panel click on the 3D Mesh tool. It's the third one down. If need be, hover over the tools you see on this panel to find it. Once found, click on the Pyramid object, hold shift and drag your mouse downward. This will revolve the mesh over the X axis while constraining the object to its position in 3D space.
4. Once you have your objects the way you want them, select both layers by holding shift and clicking on each 3D layer. Then click on the 3D menu at the top of the screen and then select "Merge 3D Layers". What this does is bring both objects into one layer where they will be positioned in 3D space.
The next set of steps can be tricky because Photoshop has a way of doing unexpected things when 3D layers are merged.
5. In order to position one 3D object over or into another 3D object, it's best that you use to Filter By:Meshes panel and the Mesh tool. From the Meshes Panel, select the Pyramid mesh and with the Mesh tool you'll more than likely have to drag upward on the green arrowhead that represents the Y axis. Drag on this until your pyramid gets inside the Sphere object.
So I think that's it. If you need more help, let us know.