Highlights
- •Three-dimensional (3D) modeling of orthodontic dental casts can be accomplished by smartphone-based stereophotogrammetry.
- •The accuracy of virtual orthodontic dental casts produced by smartphone-based stereophotogrammetry was about 0.34 mm, and the error of repeated 3D models using this method was 0.03 mm.
- •Stereophotogrammetry using smartphone devices is a simple and low-cost technology for the 3D modeling of orthodontic dental casts.
- •This method is a helpful low-cost tool for the digital archiving of dental casts, eliminating physical storage shortcomings, such as broken models and space requirements.
ABSTRACT
Background
The development of intraoral scanning technology has effectively enhanced the digital
documentation of orthodontic dental casts. Albeit, the expense of this technology
is the main limitation.
The purpose of the present study was to assess the validity and reliability of virtual
three-dimensional (3D) models of orthodontic dental casts, which were constructed
using smartphone-based 3D photogrammetry.
Methods
A smartphone was used to capture a set of two-dimensional images for 30 orthodontic
dental casts. The captured images were processed to construct 3D virtual images using
Agisoft and 3DF Zephyr software programs. To evaluate the accuracy of the virtual
3D models obtained by the two software programs, the virtual 3D models were compared
with cone-beam computed tomography scans of the 30 dental casts. Colored maps were
used to express the absolute distances between the points of each compared two surfaces;
then, the means of the 100%, 95th, and 90th of the absolute distances were calculated.
A Wilcoxon signed-rank test was applied to detect any significant differences.
Results
The differences between the constructed 3D images and the cone-beam computed tomography
scans were not statistically significant and were accepted clinically. The deviations
were mostly in the interproximal areas and in the occlusal details (sharp cusps and
deep pits and fissures).
Conclusions
This study found that smartphone-based stereophotogrammetry is an accurate and reliable
method for 3D modeling of orthodontic dental casts, with errors less than the accepted
clinically detectable error of 0.5 mm. Smartphone photogrammetry succeeded in presenting
occlusal details, but it was difficult to accurately reproduce interproximal areas.
Graphical abstract

Graphical Abstract
Keywords
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References
- British Orthodontic Society's initiative on orthodontic retention, a GDP's perspective.Br Dent J. 2018; 224: 481-486
- Storage of orthodontic study models in hospital units in the U.K.Br J Orthod. 1992; 19: 227-232
- Digital versus plaster study models: how accurate and reproducible are they?.J Orthod. 2012; 39: 151-159
- Precision of intraoral digital dental impressions with iTero and extraoral digitization with the iTero and a model scanner.Am J Orthod Dentofacial Orthop. 2013; 144: 471-478
- Orthodontic scanners: what's available?.J Orthod. 2015; 42: 136-143
- Integration and application of multimodal measurement techniques: relevance of photogrammetry to orthodontics.Sensors (Basel). 2021; 21: 8026
- Photogrammetry as an alternative for acquiring digital dental models: a proof of concept.Med Hypotheses. 2019; 128: 43-49
- Digital dental models: is photogrammetry an alternative to dental extraoral and intraoral scanners?.Dent J (Basel). 2022; 10: 1-15
- A critical assessment of the potential for Structure-from-Motion photogrammetry to produce high fidelity 3D dental models.Am J Phys Anthropol. 2020; 173: 381-392
- Concurrent validity and reliability of cephalometric analysis using smartphone apps and computer software.Angle Orthod. 2019; 89: 889-896
- The reliability and reproducibility of an android cephalometric smartphone application in comparison with the conventional method.Angle Orthod. 2021; 91: 236-242
- Accuracy of a smartphone-based orthodontic treatment-monitoring application: a pilot study.Angle Orthod. 2019; 89: 727-733
- Accuracy of capturing nasal, orbital, and auricular defects with extra- and intraoral optical scanners and smartphone: an in vitro study.J Dent. 2022; 117103916
- Monoscopic photogrammetry to obtain 3D models by a mobile device: a method for making facial prostheses.J Otolaryngol Head Neck Surg. 2016; 45: 33
- A method for economical smartphone-based clinical 3D facial scanning.J Prosthodont. 2020; 29: 818-825
- Smartphone-based photogrammetric 3D modelling assessment by comparison with radiological medical imaging for cranial deformation analysis.Measurement. 2019; 131: 372-379
- State-of-the-art three-dimensional analysis of soft tissue changes following Le Fort I maxillary advancement.Br J Oral Maxillofac Surg. 2016; 54: 812-817
- The accuracy of conformation of a generic surface mesh for the analysis of facial soft tissue changes.PLoS One. 2016; 11e0152381
- Accuracy of generic mesh conformation: the future of facial morphological analysis.JPRAS Open. 2017; 14: 39-48
- A comparison between dental measurements taken from CBCT models and those taken from a Digital Method.Eur J Orthod. 2013; 35: 1-6
- Trueness of cone beam computed tomography versus intra-oral scanner derived three-dimensional digital models: an ex vivo study.Clin Oral Implants Res. 2019; 30: 498-504
- Comparative evaluation of digitization of diagnostic dental cast (plaster) models using different scanning technologies.Dent J (Basel). 2020; 8: 79
- Linear measurements using virtual study models.Angle Orthod. 2012; 82: 1098-1106
- Current methods of assessing the accuracy of three-dimensional soft tissue facial predictions: technical and clinical considerations.Int J Oral Maxillofac Surg. 2015; 44: 132-138
- Assessment of regional asymmetry of the face before and after surgical correction of unilateral cleft lip.J Craniomaxillofac Surg. 2018; 46: 974-978
- The evaluation of Cloudcompare software in the process of TLS the evaluation of Cloudcompare software in the process of TLS point clouds registration.RevCAD J Geod Cadastar. 2016; 21: 117-124
- A comparison of trueness and precision of 12 3D printers used in dentistry.BDJ Open. 2022; 8: 14
- Three-dimensional analysis of lip changes in response to simulated maxillary incisor advancement.Angle Orthod. 2020; 90: 118-124
- Impact of orthodontic brackets on intraoral and extraoral scans.Am J Orthod Dentofac Orthop. 2022; 162: 208-213
- Assessment of simulated vs actual orthodontic tooth movement with a customized fixed lingual appliance using untreated posterior teeth for registration and digital superimposition: a retrospective study.Am J Orthod Dentofacial Orthop. 2022; 161: 272-280
- Scanning accuracy of nondental structured light extraoral scanners compared with that of a dental-specific scanner.J Prosthet Dent. 2021; 126: 110-114
- Accuracy of laser-scanned models compared to plaster models and cone-beam computed tomography.Angle Orthod. 2014; 84: 443-450
- Three-dimensional analysis of digital models generated from intraoral, extraoral, and CBCT scanning devices.J Dent Maxillofac Res. 2019; 2: 1-7
- Dental measurements and Bolton index reliability and accuracy obtained from 2D digital, 3D segmented CBCT, and 3d intraoral laser scanner.J Clin Exp Dent. 2017; 9: e1466-e1473
Article info
Publication history
Published online: December 16, 2022
Accepted:
November 18,
2022
Received in revised form:
October 10,
2022
Received:
August 15,
2022
Footnotes
Funding: This study was supported by the National Natural Science Foundation of China under the grant number 82000996.
Competing interests: Authors have completed and submitted the ICMJE Form for Disclosure of potential conflicts of interest. None declared.
Provenance and peer review: Non-commissioned and externally peer reviewed.
Identification
Copyright
© 2022 World Federation of Orthodontists. Published by Elsevier Inc. All rights reserved.