Accuracy of Facial Digitization Using a New Mobile Device-Compatible 3D Scanner for Malocclusion

The three-dimensional (3D) facial scanning system plays a crucial role in orthognathic surgery, with significant advancements in related technologies. However, high costs and limited portability have restricted the accessibility of existing scanners, highlighting the need for a mobile device-based 3D facial scanning system. To address this, a new mobile device-compatible 3D facial scanning software (i3Dface) was developed, installed, and tested on mobile tablets. From August 2021 to December 2022, 50 volunteers participated in evaluating i3Dface's reproducibility and accuracy for facial digitization and orthognathic applications. i3Dface demonstrated strong reproducibility in environments with optimal light intensity (600-2100 lux) and shooting angles (-20 degrees-10 degrees). When comparing absolute deviations in facial measurements, i3Dface showed no significant difference from the established stereophotogrammetry system (3dMD), aligning closely with manual clinical measurements. In assessing 3D spatial deviation, i3Dface's accuracy varied by facial region, with the highest accuracy (0.59 ± 0.13 mm) in the chin area and the lowest (1.17±0.16 mm) in the midface. For clinical applications in orthognathic surgery, i3Dface facial images showed effective alignment with CBCT soft tissue images. In summary, i3Dface offers reproducibility in suitable environments and accuracy comparable to 3dMD, meeting essential clinical requirements and supporting digital technology use in orthognathic surgery.