Evaluation of 3D facial scanners: trueness and precision

This is an in-vitro study performed on a mannequin model, which evaluates the precision and trueness of facial scanners (FSs) by analyzing facial scans from ten 3D scanners, consisting of five professional devices and five mobile applications. A 3D facial model with human-like dimensions, shape, and proportions, featuring reference points, was used to standardize measurements. A reference file was acquired using an industrial laser scanner, specifically the Edge 14000 model from FARO® (Certified ISO 9001 - calibration ISO/IEC 17025:2017 accreditations). Each FS performed six scans. Computer-aided design (CAD) software was then used for precise measurements and alignments. The six scans from each FS were compared to evaluate precision and trueness, both locally and globally, against the reference file. Scans produced by the applications showed significant differences in image resolution and dimensional scale, making it impossible to achieve a match in Exocad. In contrast, the professional FSs exhibited dimensional matching with the reference file in .stl format, enabling comparable measurements that the applications could not provide. Consequently, the comparison of professional FSs with the reference file demonstrated overall trueness. Given the limitations of this in-vitro study, significant dimensional discrepancies in the currently tested apps should continue to be evaluated. The professional FSs considered in this study demonstrated satisfactory trueness and precision when compared to the reference file, making them suitable for enhancing dental treatment plans. This study evaluates the precision and trueness of professional and mobile facial scanners, highlighting their limitations in dental applications. The findings emphasize the reliability of professional scanners for precise measurements, which aid in treatment planning and digital workflows.