# Diagnostic Accuracy and Agreement Between AI and Clinicians in Orthodontic 3D Model Analysis
## 2 Materials and Method
### Measurements  
The selected patient models were uploaded to two web-based platforms: Titan Dental Design ([[https://titandentaldesign.com/](https://titandentaldesign.com/)]([https://titandentaldesign.com/](https://titandentaldesign.com/)), accessed on 8 July 2025, v1.2.4 a2) and SoftSmile ([[https://softsmile.com/](https://softsmile.com/)]([https://softsmile.com/](https://softsmile.com/)), accessed on 8 July 2025, TPA version 1.13.2). For each case, upper and lower intraoral scan files were manually oriented within the software, followed by automatic tooth segmentation. Minor manual adjustments to the gingival margins were made when necessary. The same patient models were also imported into the computer-based 3 Shape OrthoAnalyzer software (OrthoAnalyzer 2019; 3 Shape, Copenhagen, Denmark), where all measurements were manually performed by orthodontists using the program's semi-automatic tools. In Titan Dental Design (Figures 1-6), the platform automatically generated the following measurements:  
* Bolton analysis (overall and anterior)
* Overjet and overbite measurements
* Angle classification (right and left)Figure 3: Model analysis in the Titan Dental Design program. **(I)**: Space analysis in the maxilla—mesiodistal widths of the teeth and the available arch length. **(II)**: Space analysis in the mandible—note how the arch form is influenced by the tooth alignment in the software. **(III)**: Overjet and overbite measurements. **(IV)**: Available arch length measured from the distal of the first molars (tooth #6); space analysis was limited to the region up to the distal line of the first molars. Figure 2: Workflow in the Titan Dental Design program. **(A)**: AI-assisted teeth segmentation. **(B)**: Adjustment of facial axis and roots generated by the software. **(C)**: Upper and lower arches ready for tooth movement planning after segmentation. **(D)**: Automatically generated cutting line (for clear aligner margins). In SoftSmile (Figures 7 and 8), only the Bolton analysis was evaluated, as the platform's space calculations did not encompass the full dental arch. The 3 Shape OrthoAnalyzer (Figures 9 and 10) was used as the primary tool for manual measurements, with all analyses performed directly by three orthodontists. Two of the orthodontists had over ten years of clinical experience, while the third had one year of post-specialization experience. All examiners were trained in digital model analysis and had at least three years of experience using the 3 Shape OrthoAnalyzer software. The 3 Shape OrthoAnalyzer was selected as the reference standard for this study due to its well-established accuracy and reliability in orthodontic measurements, as supported by numerous studies in the literature [30; 32; 33]. For numerical data, the average values obtained from the three orthodontists were used. For categorical data, the value agreed upon by at least two of the three orthodontists was accepted as the final decision. This process was carried out by a resident. Figure 4: Mesiodistal width measurements of the teeth in the Titan Dental Design software. Figure 5: An AI-assisted case evaluation in the Titan Dental Design program interface. Figure 8: Model analysis and various stages in the SoftSmile program. Figure 6: Web-based AI panel displaying measurements after segmentation in the Titan Dental Design program. Figure 7: Workflow in the SoftSmile Program. (**a**): AI-assisted identification of mesiodistal tooth widths. (**b**): Automatic detection of undesired measurement areas. (**c**): Tooth segmentation. (**d**): Generation of virtual roots by software. Orthodontists did not have access to the data generated by AI systems. Their involvement in the AI-assisted workflows was limited to assessing the quality of the automated segmentation. All AI-generated measurements were collected independently by a resident to maintain a clear separation between the manual evaluation and AI data processing steps.