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Are different photogrammetry applications on smartphones sufficiently reliable?
Gülden Karabiber1, Hanife Nuray Yılmaz1, Gamze Yıldırım1
1Department of Orthodontics, Marmara University, Istanbul, Türkiye.
Korean Journal of Orthodontics
|January 24, 2025
Summary
The 3dMD system demonstrated superior accuracy and reliability in facial measurements compared to Qlone and Magiscan smartphone applications when assessed against direct anthropometry. Further research is needed for clinical application of these mobile tools.
Area of Science:
- Medical Imaging
- Anthropometry
- Photogrammetry
Background:
- Direct anthropometry (DA) is a standard for facial measurements.
- Advancements in smartphone photogrammetry offer potential alternatives.
- Comparing the accuracy of these digital tools is crucial for clinical adoption.
Purpose of the Study:
- To evaluate and compare the accuracy of Qlone, Magiscan, and 3dMD digital methods against direct anthropometry for facial measurements.
- To determine the reliability and trueness of each method.
Main Methods:
- Forty-one patients had 16 facial landmarks marked.
- 18 linear measurements were taken using 3dMD (multicamera), Qlone, and Magiscan (single-camera smartphone apps), alongside DA.
- Calibration ensured 1:1 correspondence for digital methods.
Main Results:
- 3dMD showed excellent trueness (0.95 ± 0.62 mm average difference) and high reliability.
- Magiscan and Qlone had higher average differences (1.51 ± 1.11 mm and 2.14 ± 1.69 mm, respectively).
- Magiscan and Qlone exhibited more unreliable values (> 2 mm) than 3dMD.
Conclusions:
- 3dMD provides highly accurate and reliable facial measurements, outperforming Qlone and Magiscan.
- While Magiscan and Qlone show promising trueness, further studies are required before clinical implementation.
- Digital photogrammetry, particularly 3dMD, shows potential for precise facial analysis.
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