This page is for dental researchers, postgraduate students and the IT staff who support them in dental schools. Medical imaging has a large open-source ecosystem, but almost none of it was built for dentistry, and several well-known names stopped developing years ago. Here is what each tool is honestly good for when your data is radiographs, CBCT volumes or scanned models.
The short answer: most dental theses need only ImageJ / Fiji for measurements on radiographs, histology and photographs. For 3D CBCT work with a graphical interface, use ParaView or medInria. If you write Python, ITK and VTK are the standard building blocks for segmentation and STL export. GIMIAS and NIRFAST are dormant and not dental. None of these tools is a medical device: results are for research and teaching, not diagnosis.
The short list
| Program | Best for | Licence | Platforms | Status |
|---|---|---|---|---|
| ImageJ / Fiji | 2D measurements on radiographs, histology, photos | Free, open source (public domain, BSD-2, GPL) | Windows, macOS, Linux | Active, 1.54t |
| ITK | Segmentation and registration in code | Free, open source (Apache 2.0) | Windows, macOS, Linux | Active, 5.4.7 |
| VTK | 3D rendering, surfaces and STL in code | Free, open source (BSD 3-Clause) | Windows, macOS, Linux | Active, 9.7.1 |
| ParaView | GUI volume rendering and STL export | Free, open source (BSD 3-Clause) | Windows, macOS, Linux | Active, 6.1.1 |
| medInria | GUI segmentation and scan-to-scan registration | Free, open source (BSD-style) | Windows, macOS, Linux | Active, 4.0.2 |
| SMILI | Quick look at volumes and STL/PLY meshes | Free, open source (BSD-style) | Windows, macOS, Ubuntu | Active, 2.0 |
| Mango | ROI volume statistics for teaching | Free, non-commercial research only | Windows, macOS, Linux | Dormant, 4.1 (2019) |
| BioImage Suite Web | Browser-based neuroimaging analysis | Free, open source (Apache 2.0) | Browser, Windows, macOS, Linux | Desktop 1.0 (2018) |
| OpenREM | Radiation dose monitoring | Free, open source (GPLv3) | Server, web browser | 1.0 in beta |
| GIMIAS | Reproducing old research only | Free, open source (BSD) | Windows, Linux | Dormant since 2016 |
| NIRFAST | Near-infrared optical tomography | Free, open source (BSD) | Windows, macOS, Linux | Dormant since 2018 |
ImageJ / Fiji
ImageJ is the tool a dental researcher is most likely to use. Fiji is its distribution with Java, the updater and hundreds of plugins included, so install Fiji. Calibrate with Analyze > Set Scale or the DICOM pixel spacing, then measure lengths, angles, areas and mean grey values; results export to CSV. The BoneJ plugin adds trabecular measurements, and macros process hundreds of images the same way. Published dental studies have used ImageJ for relative bone density on panoramic radiographs and ImageJ with BoneJ on periapical radiographs in an animal implant model. Limits: it is 2D-first, and grey values only compare between images taken under the same conditions. On Windows, unpack Fiji into your user folder, not Program Files, or the updater runs into permission problems.
ITK (Insight Toolkit)
ITK is a library for filtering, segmenting and registering medical images from C++ or Python, with no user interface of its own. pip install itk is enough to start, and itk.imread() on a DICOM folder returns one sorted 3D volume. Typical dental research uses: smooth a CBCT, threshold it and keep the largest connected component to isolate bone, align two scans of the same patient, or resample a folder of studies into a machine-learning dataset. It is also the engine inside 3D Slicer, ITK-SNAP and medInria. Choose it if you need reproducible pipelines. ITK 6 is in beta, so target the 5.4 series today.
VTK (Visualization Toolkit)
VTK is ITK’s partner: ITK analyses images, VTK displays them and builds meshes. From a segmented label map it extracts a surface with flying edges or marching cubes, smooths it, decimates it and writes STL, which is the usual free route from CBCT to a printable model. It also volume-renders CT data for lectures. One trap for dental data: the built-in DICOM reader does not handle compressed or multi-frame files, which many CBCT exports use, so read them with ITK first. Choose VTK when you want the 3D part of your own tool.
ParaView
ParaView is Kitware’s desktop application built on VTK, and the easiest way to get CBCT visualisation without code. There is no separate medical edition; the standard download reads a DICOM directory, volume-renders it on the GPU, extracts a bone surface with the Contour filter and saves it as STL. A Python shell records and automates each step. Limits: the classic DICOM reader handles uncompressed files only, a threshold will not separate individual teeth or the two jaws, and the interface is built for scientists, so plan an hour with the official getting-started guide. Choose it for teaching images and quick surface models.
medInria
medInria from Inria in France is the most complete point-and-click research viewer here. It imports DICOM, including CBCT, into a local database, offers 3D rendering and reslicing, paintbrush and polygon segmentation, NL-means denoising and several registration methods for aligning an earlier and a later scan. Inria states that it is not CE marked or FDA approved. Its diffusion MRI and tractography tools are irrelevant to dentistry, and it has no panoramic curve or implant tools. Use the stable 4.0.2 for work you must reproduce; 5.0 is still a beta.
SMILI
SMILI from CSIRO and its viewer sMILX are the lightest option here: drag in a volume and an STL or PLY model, overlay a label map to check a segmentation, then smooth or decimate the mesh and save it. A Python console automates the same steps across a folder of models. Version 2.0 (June 2025) has installers for Windows, macOS and Ubuntu 22.04; on a Mac you may need to clear the quarantine flag the developers describe. The documentation is thin and the team small, so treat it as a handy viewer rather than a platform.
Mango
Mango from UT Health San Antonio is a simple way to outline a structure across slices and get its volume, mean and standard deviation as CSV, for example a cyst-like lesion or a graft area in a thesis. It opens DICOM and NIfTI and builds surfaces for lectures. Its licence restricts it to non-commercial research and education and excludes clinical use. Development is dormant: the last desktop release, 4.1, is from 2019, and surfaces export as VTK or GIFTI, not STL. It also appears in our dental DICOM viewers hub.
BioImage Suite Web
BioImage Suite Web from Yale runs in the browser with desktop and command-line versions, and processes everything on your own computer without uploading data. It is built for neuroimaging and states that it is not approved for clinical use. For dental work its value is limited to viewing and hand-editing a volume without installing anything, and only after converting DICOM to NIfTI, the format its viewers read. The last numbered desktop release is 1.0 from 2018; the web app has no numbered releases.
OpenREM
OpenREM is not an image analysis tool at all: it is a server that collects radiation dose data from X-ray, CT and fluoroscopy equipment and presents charts for medical physicists. It belongs in this list because dental schools and hospitals doing dose audits ask about it. The 1.0 beta can import panoramic exams; nothing documents intraoral or dental CBCT support, so test a sample study first. The stable release is 0.10.0 from 2019. It is free and open source under GPLv3.
GIMIAS
GIMIAS was a plug-in framework for image analysis and simulation from Universitat Pompeu Fabra in Barcelona, with prototypes for cardiology, cerebral aneurysms and neurology. It is dormant: the last release, 1.8.r1, came out in 2016, the Linux packages target Ubuntu 14.04 and Debian 8, and the old project domain no longer hosts it. There is no documented dental use. Open it only if you must reproduce or study older work built on it; for new projects, medInria or ITK-based tools are the maintained route.
NIRFAST
NIRFAST from Dartmouth models how near-infrared light travels through tissue and reconstructs diffuse optical tomography images. It pairs NIRFAST-Slicer, a segmentation and meshing front end based on 3D Slicer, with NIRFAST-Matlab, the finite-element light-transport engine, which needs a separately licensed MATLAB. It has no dental features and we found no dental examples. Releases stopped in 2018 with NIRFAST-Matlab 9.1 and NIRFAST-Slicer 2.0; development continues in the Python successor NIRFASTer-FF, also free under a BSD licence. It is relevant only if your research is optical imaging, such as light-transport simulation in tissue, not radiographs or CBCT.
How to choose
- 2D radiographs, histology or clinical photos: Fiji. Save the exact ImageJ version in your methods section.
- View and measure a CBCT volume: ParaView or medInria; Mango if your project is non-commercial research.
- Printable STL from CBCT: the ParaView Contour filter for a rough surface, or an ITK plus VTK script for a controlled pipeline. More on mesh work is in our 3D scanning and mesh tools hub.
- Check a segmentation or clean a model: SMILI.
- Anonymise before you start: strip patient data with a tool such as dcm4che and keep the originals untouched.
- Check maintenance status: a thesis that runs for three years should not depend on a dormant tool. Prefer active projects, and fix versions for reproducibility.
FAQ
ImageJ or Fiji: which should I download?
Fiji. It is ImageJ with Java, the updater and the common plugins already installed. Choose the “Latest” build unless you run a very old system.
Can ImageJ open dental DICOM X-rays?
It opens some DICOM files directly, and Fiji’s Bio-Formats importer handles more. Exporting radiographs as uncompressed TIFF is the reliable fallback.
What is the difference between ITK and VTK?
ITK processes images: filtering, segmentation, registration. VTK renders images and meshes and writes formats such as STL. Most pipelines use both.
Is there a ParaView medical edition?
No. The standard ParaView download reads DICOM and volume-renders CT data.
Can these tools be used for diagnosis?
No. They are research and teaching tools; medInria, Mango and BioImage Suite Web say so explicitly.
Which free tool makes an STL from a CBCT scan?
ParaView without coding, or ITK and VTK in Python for more control over segmentation.
Last updated: 29 September 2026 · SoftProDents editorial team. Licence, version and platform details are checked against each developer's official documentation; none of the tools listed here should be treated as a certified medical device unless its vendor says so.
