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Hey, thank you for replying to this old thread. I got sometimes to scan some fake models to eliminate any legal reasons for publishing real patients data on the Internet.

I published all data in this Github repo: https://github.com/thangngoc89/dxd-file-format

I also tried to scan something simple like an sphere or a pencil without any success. The software only recognize tooth-like structures.

Luciky, it can exports to STL files with 100% triangles that can be imported to others dental CAD software so I hope it would help with the progress.



Wow, the colorization the software provides is seriously impressive.

It's regrettable but understandable that the software only recognizes/accepts teeth considering the postprocessing it clearly does.

And CC0ing the model data is pretty much the textbook approach to analytical freedom :)

(And just to confirm, STL/etc->DXD isn't possible?)


Yes it is possible to go from STL to DXD. But last time I try that feature, the software crashed. I will try to do it again when I’m back at the office.

Thank you for reminding me about this.

Quick update: opening the DXD file with a hex editor, there is a XML file defining the metadata of the current file and a public RSA 1024 key. I’ve been scouring around to find the private key with no success.


Just saw this, sorry for the delay.

Hmmmm. Ideally that key is only being used for attestation/authentication, not encryption. In this case, you definitely don't want to locate the private key, because that key's confidentiality is what verifies the integrity of the scans made by your device.

Also, said private key might be specific to your copy of the software to create a chain of custody to your machine for medical purposes, or even more likely for licensing reasons.

In any case, if it's being used for encryption, that would amount to an unfortunate DRM situation that might be a bit of a hornet's nest to fiddle with, because of the high likeliness the key is being used for license enforcement etc (tracking scans made by copies of software deemed illegitimate etc).

It's very cool you can go from STL to DXD though. Now I'm curious, was the STL file that crashed the software originally generated from a DXD file created by the software? It originally being a DXD should be irrelevant, but chances are the pipeline inside the software chokes on things that aren't models of teeth. This does admittedly make the reverse engineering process trickier...




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