An in vitro Comparison of Accuracy Between Three Different Face Scanning Modalities

Area of Science:

• 3D scanning technologies
• Digital imaging
• Facial anthropometry

Background:

• Accurate 3D facial scanning is crucial for applications like virtual reality, medical simulations, and forensic analysis.
• Evaluating the performance of different 3D scanning technologies is essential for selecting the most suitable device for specific applications.

Purpose of the Study:

• To compare the trueness and precision of three different 3D scanners (structured light, stereophotogrammetry, and laser scanning) for digitizing a mannequin head.
• To assess scanner performance across the entire face and specific facial partitions.

Main Methods:

• A reference mesh was acquired using a reference scanner.
• Test meshes were acquired using Einscan Pro HD (structured light), RayFace100 (stereophotogrammetry), and Proface 3D Mid (laser scanner).
• Meshes were analyzed for discrepancies in four horizontal areas, and statistical tests (One-way Anova, pairwise comparisons) were used to compare trueness and precision.

Main Results:

• Significant differences in accuracy and trueness were found among scanners for both the complete face and delineated facial areas (P < 0.01).
• Einscan Pro HD exhibited significantly higher accuracy for the complete face and higher trueness for all facial partitions.
• RayFace100 showed higher trueness in the middle facial region, while Proface 3D Mid had lower trueness in the upper facial third.
• All scanners achieved accuracy levels below the 2.00mm threshold, indicating acceptable performance.

Conclusions:

• Facial scanning accuracy is significantly influenced by the type of scanner used.
• The location of the scanned surface area impacts the trueness of different 3D scanning devices.
• All evaluated scanners met acceptable accuracy thresholds for facial digitization.