# Dental Arch Research

**URL:** <https://discourse.slicer.org/t/dental-arch-research/43060>\
**Category:** Support\
**Created:** [May 23, 2025, 11:08am UTC](https://discourse.slicer.org/t/dental-arch-research/43060 "2025-05-23T11:08:24Z")\
**Posts on this page:** 3\
**Page:** 1

<div class="post-metadata">

**Author:** ![cekrebs](https://avatars.discourse-cdn.com/v4/letter/c/73ab20/32.png) [@cekrebs](https://discourse.slicer.org/u/cekrebs)\
**Post date:** [May 23, 2025, 11:08am UTC](https://discourse.slicer.org/t/dental-arch-research/43060/1 "2025-05-23T11:08:24Z")

</div>

Hi everyone! I am currently trying to compare two scans of lower teeth (one scan of a plastic typodont, one scan of a 3D printed version of the typodont). The STL files of the models after being scanned are almost identical with minor differences from the 3D printing process.

I was able to upload the two STL files. Now I am hoping to align/superimpose the two dental arches, then quantify the differences between the two in mm. For example, where the 3D printer made the teeth too big, too small, etc.

Let me know if anyone would know how to do this.

---

<div class="post-metadata">

**Author:** ![cekrebs](https://avatars.discourse-cdn.com/v4/letter/c/73ab20/32.png) [@cekrebs](https://discourse.slicer.org/u/cekrebs)\
**Post date:** [May 23, 2025, 8:40pm UTC](https://discourse.slicer.org/t/dental-arch-research/43060/2 "2025-05-23T20:40:43Z")

</div>

Ok I was able to overlay the two STL file of the two dental arches. I would love help with how to compute the differences between the two now! Example - places between the two arches that are different and differences in mm.

---

<div class="post-metadata">

**Author:** ![chir.set](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/chir.set/32/66982_2.png) [@chir.set](https://discourse.slicer.org/u/chir.set)\
**Post date:** [May 23, 2025, 9:05pm UTC](https://discourse.slicer.org/t/dental-arch-research/43060/3 "2025-05-23T21:05:37Z")

</div>

> [@cekrebs](#):
>
> I was able to overlay

> [@cekrebs](#):
>
> compute the differences between the two

Try the `Combine models` module in the `Sandbox` extension.