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I have meshes of human dental jaws in the image below. I would like to put them in correct anatomical position. I would also like to rotate them in correct anatomical fashion. How can I achieve these two goals.

I'm trying to overlapped and solidify object in a simple example, to plan maxillo facial surgery. The idea is to put the jaw with the teeth into an other position during the surgery. So I would like to "tell" to the lower jaw that I just cut to "move into this position and to stay there".

In this exemple, I would like the teeth from the back to overlapped the teeth in front of them (mirroring lower jaw in the good position). Is it possible to do it by selecting region of interest (like the top of the teeth of the back) and show to Blender the similar point in the mirroring teeth?

enter image description here

The second question is during the occlusion of teeth. When I want to close the jaw (if the CT scan is not in occlusion), I would like to solidify the teeth of the upper jaw. Like that, when I'm trying to close the lower jaw, I would find the contact with the teeth, and not passing through the upper jaw...

enter image description here

Thank you again for your help! Blender for ever!

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    $\begingroup$ In your images above I think I see the same jaw twice. That does not seem reasonable to me but I am not a surgeon. It seems correct placement would require the cranium visually to be present to obtain a context for correct placement. A screen image from you showing more cranium would help. I think your questions are not difficult and you or your workmates may need to see a tutorial series about blender Link youtube.com/…. $\endgroup$ – atomicbezierslinger Aug 30 '15 at 22:55
  • $\begingroup$ Are the upper and lower jaws and cranium already three separate objects? $\endgroup$ – atomicbezierslinger Aug 30 '15 at 23:05
  • $\begingroup$ What do you mean by saying "solidify"? And is this a question only about modeling (put polygons in the right place) or rigging also (assigning constraint between polygons, such as hinges, pivots, rotation restraints...)? $\endgroup$ – Carlo Aug 31 '15 at 0:59
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Align identical object by a twin tris

Let's suppose you have an object and another one, very similar to the first, and you want to overlay the two.

If they are not perfectlty identical, you should probably start an iterating computation that would progressively guess the function that best fit all the vertex positions...

...if instead they are identical (as in your case), but with different transformations applied such as in the picture below:

enter image description here

the problem is much more simple. If you'll get able to align one triangular face to the corrispective one, the whole mesh will be aligned. I would suggest to use the Precise Align add-on.

Basically you have to activate edit mode of both object (one at time), select the same triangular faces by selecting the vertices in the same ordere and than create a parented empty with the add-on command:

enter image description here

These two empty are now associated with the mesh. All you have to do is to match position and rotation of the empty object and the two jaws will follow their trasformation:

enter image description here

Overlapped!

enter image description here


Limit object's rotation

Easiest way to set up a moving jaw is to first of all add an empty that would represent the rotation pivot and than parent the upper jaw to it.

enter image description here

Now the jaw will follow empty's transfrormations.

enter image description here

Add a Limit Rotation constrain to the empty and assign min e max angles to limit the rotation of the jaw to a given range too.

Credits: jaw's model by lucasfalcao from Blendswap

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As to your second part, have you looked at RigidBody and RigidBody Contstraints?

http://wiki.blender.org/index.php/Doc:2.6/Tutorials/Physics/Rigid_Bodies

https://www.blender.org/manual/physics/rigid_body/constraints.html

For the first part though, I'm very new to blender but I think it would probably be easier to export your models to something like Unity, you could then run clever scripts and colliders etc. to do the detection of areas and move parts accordingly. Although saying that there may well be a way to do it in Blender.

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  • Press G , to grab and move the mesh.
  • Press R, to rotate the jaw mesh.
  • Press Numpad 1, 3, 7 to see your model from different viewpoints.
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