InVivoDental Viewer
InVivoDental Viewer is Anatomage’s free Windows viewer for Invivo (.inv) CBCT case files. It is legacy software: Osteoid, which now runs Invivo, no longer offers it and points users to Invivo Workspace for viewing .inv files.
ParaView
ParaView is Kitware’s free, open-source (BSD 3-Clause) application for 3D scientific visualisation. It can load CT/CBCT DICOM series, volume-render them and export surfaces as STL for research and teaching. There is no separate medical or dental edition.
VTK (Visualization Toolkit)
VTK (Visualization Toolkit) is a free, open-source BSD library for 3D rendering, volume rendering and mesh processing from C++ or Python. It has no dental module, but it can turn a segmented CBCT into an STL and powers tools like ParaView and 3D Slicer.
ITK (Insight Toolkit)
ITK (Insight Toolkit) is a free, open-source Apache 2.0 library for segmenting, registering and filtering medical images from C++ or Python. It has no GUI and no dental tools; researchers use it to build CBCT processing pipelines.
Meshroom (AliceVision)
Meshroom is free, open-source (MPL-2.0) photogrammetry software from AliceVision that turns overlapping photos into a textured 3D mesh. Official builds are for Windows and Linux; full-quality reconstruction needs an NVIDIA CUDA GPU.
Open CASCADE Technology (OCCT)
Open CASCADE Technology (OCCT) is a free, open-source C++ CAD geometry kernel (LGPL 2.1 with exception) for solid modeling, STEP/IGES/STL exchange and 3D display. It has no dental features; developers use it to build their own CAD tools.