Creating a form-fitting case around a hi-facet count object

[neils.nygaard]

Hi all, so I am relatively new to CAD programs.  I took two classes in university and am now working for my father-in-law designing sleep apnea appliances.  Right now, I have an STL scan of his teeth and I want to create a mold that will fit around them.  I reduced the facet count in order to convert the mesh scan into a solid object but now I am at a loss of how to make a sort of retainer/case that fits onto the teeth like something you get from a dentist after you get your braces off to keep your teeth from moving back.

I've tried using the shell command and changing it to an exterior shell and selecting all of the facets/faces that make up the teeth.  I tried using the boundary fill command from the create drop down menu but I'm not sure I know how to use it properly.

Attached I have a picture of just the bottom half or so of the teeth where I want the appliance to fit over, I also have the .obj of the original model of the teeth.  He'd like me to figure this out ASAP so any help would be nice!

Thank you!

 - Christian

[SaeedHamza]

You can convert the mesh into a BRep, and then create and extrusion (retainer)

Use the converted mesh as a cutting tool for the created extrusion to subtract the teeth from it (retainer)

[neils.nygaard]

So i tried that, at least I think I did, and while it worked to a certain extent, I am left with a very blocky looking appliance vs something smoothed and comfortable for wearing over night.  Is there some sort of way that I can preserve the general contours of the teeth so that the retainer looks like a thin layer of plastic that simply overlays the teeth?

[TrippyLighting]

To be honest, I would probably not start with this in Fusion 360. It might end up here being a quad mesh but i'd start it in Blender or another Sub-D mesh modeling app.

I'd use that scan in Blender as he basis. Here is a Blender retopology (of sorts) tutorial that should get you started.

In general that is a very quick way to have a detailed high fidelity model. I

I've used this for example to help a jeweler to model jewelery that needs to fit the contour of a face .

The resulting quad mesh you can then import into Fusion 360 and convert into a T-Spline. Blender can be a bear to learn, but once you get the hang of it, for wok like this it's a very powerful companion to Fusion 360.

[neils.nygaard]

Awesome thanks!  I will check this out and see how I do.  I played around with blender five or six years ago but definitely didn't do anything this complicated.

I'll let you know if it works!