Additive manufacturing, in combination with virtual surgery planning, leads to the predictability of complex surgical cases. To guarantee patient safety, three-dimensional (3D) print quality must be ensured and verified. The aim of this study is to compare the accuracy of an optical white-light desktop scanner (OWLDS) and a cone beam CT (CBCT) scanner to that of a multi-slice CT scanner (MSCT) for scanning and digitizing 3D anatomical models. Twenty-two removable parts of a CE-certified anatomical skull, used as a patient-specific surrogate in a clinical workflow, were each scanned by MSCT, CBCT, and OWLDS scanners. The accuracy of the scanning modalities was investigated through a part comparison analysis of the stereolithography (STL) files derived from the different scanning modalities. The high-resolution OWLDS STL files show the smallest overall surface match deviation, at 0.04 mm, compared to the MSCT STL files. The CBCT STL files show an overall deviation of 0.07 mm compared to the MSCT STL files. This difference between the scan modalities increases as the volume of anatomical models decreases. The OWLDS is a safe, cost-effective, user-friendly, and highly accurate scanning modality suitable for accuracy evaluation during the manufacturing process of in-house 3D models. For smaller models, high-resolution optical scans are recommended.

3D printing is an important part of orthognathic surgery by enabling accurate anatomical models for preoperative planning. While Stereolithography (SLA) is widely regarded as the gold standard due to its high precision, recent improvements in Fused Deposition Modeling (FDM) raise the question whether PLA-based dental models can provide comparable dimensional accuracy at a lower cost. This study compares FDM and SLA dental models to evaluate whether FDM represents a clinically viable alternative. STL files derived from maxillary and mandibular intraoral scans (IOS) of 20 patients, yielding 40 dental models, were fabricated using both printing techniques. All models were aligned to the reference STL files and analyzed for dimensional deviations. SLA models demonstrated significantly higher dimensional accuracy than PLA-based FDM models, with lower maximum deviations from the reference STL (1.42 mm vs. 1.84 mm). Both techniques achieved clinically acceptable accuracy for splint fitting, with mean deviations below 0.05 mm. Regarding internal validity, both printers showed high reproducibility, although FDM models exhibited a higher median deviation compared to SLA models (0.0267 mm vs. 0.00145 mm). While SLA remains preferable for high-precision indications, FDM offers a cost-effective alternative for routine clinical use without compromising clinical applicability.

Background: Three-dimensional facial anthropometry is increasingly used in orthodontics and orthognathic surgery. Conventional face scanning systems such as Vectra^® and 3dMD^® are well validated but remain costly and technically demanding. The MetiSmile^® 3D face scanner provides a more affordable and portable alternative, yet its accuracy and reproducibility have not been rigorously evaluated. Methods: Validation was performed on a standardized mannequin head in two phases. Phase 1 assessed mesh reproducibility under artificial lighting (AL), natural lighting (n-AL), and after mesh-refinement (AL-F). Landmark-based pre-registration with Iterative Closest Point refinement was applied; root-mean-square error (RMS) and distance maps were calculated. In phase 2, three observers (student, resident, consultant) performed 14 predefined linear measurements by direct anthropometry (DA) and digital anthropometry (DiA). Intra- and inter-observer reliability was evaluated using intraclass correlation coefficients. Results: Phase 1 yielded mean RMS values of 0.041 mm (AL), 0.043 mm (n-AL), and 0.030 mm (AL-F), with largest deviations near eyes, alar regions, and lip commissures. Phase 2 showed excellent ICCs (≥0.997) and mean absolute DA–DiA differences of 0.25–0.33 mm, with only few differences > 2 mm. Conclusion: The MetiSmile^® scanner generates highly reproducible meshes and clinically acceptable linear measurements on mannequin models. Further validation on live subjects is warranted before routine clinical application.