Clinical evaluation of the accuracy of two face scanners with different scanning technologies

Abstract

Objectives: This study compared the clinical accuracy of two different stationary face scanners, employing progressive capture and multi-view simultaneous capture scanning technologies. Methods: Forty dentate volunteers participated in the study. Soft tissue landmarks were marked with a pen on the participants’ faces to measure the distances between them. Clinical measurements were manually obtained using a digital vernier caliper by two independent examiners. The participants were then scanned using one of two stationary face scanners: Obiscanner (Fifthingenium), which employs progressive capture technology requiring the subject’s head to rotate during image acquisition, or RAYFace (RAY), which utilizes multiple cameras to simultaneously capture a complete 3D image. The scans were imported into mesh-processing software, and digital measurements were taken by the same examiners. Data analysis included pairwise comparison tests and the calculation of the intra-class correlation coefficient (ICC; α = 0.05). Results: Digital measurements were significantly longer than clinical measurements across all measured distances (p < 0.001). Comparisons between the scanners revealed that vertical measurements using RAYface exhibited greater percentage differences compared to those using Obiscanner (p < 0.05), while horizontal measurements were more variable with Obiscanner than those obtained using RAYface (p < 0.05). Intra-examiner differences were significant for both methods (p < 0.001), although inter-examiner differences were only significant for clinical measurements (p < 0.001), not for digital measurements (p > 0.05). Inter-examiner reliability for digital measurements was high (ICC≥0.99). Conclusions: Significant differences were observed in the accuracy of the two stationary face scanners using progressive capture and multi-view simultaneous capture scanning technologies, with each device demonstrating specific strengths and limitations. Clinical Significance: Although face scanners offer relatively high accuracy and consistency, particularly across different acquisition technologies, careful consideration of their performance characteristics is essential for optimizing accuracy in facial measurements