The Precision and Reliability of Facial Measurements Obtained Using Conventional and Digital Laser Scanning Methods: an in Vivo Study

Aim To evaluate the precision and reliability of the conventional method of facial measurement with the smartphone-based LiDAR (Light Detection and Ranging) scanning method. This prospective study was performed on forty-seven patients. Measurements between anthropometric soft tissue landmark points were obtained on each participant by two operators, who were blinded to each other’s measurements for interrater reliability, using two techniques: i) conventional (C) method using Vernier calliper (Mitutoyo, Kawasaki, Japan) and ii) LiDAR (L) method using the LiDAR scanner (iPhone-12Pro, iOS 15.2.1, Apple Inc.). Intraclass Correlation Coefficient (ICC) analysis was used to evaluate the intra-observer reliability of the repeated measurements and measurement accuracy between the different measurement methods. On comparison of the mean values of conventional and LiDAR vertical measurements, the values are statistically not significant with a p-value of 0.704. On comparison of the mean values of conventional and LiDAR horizontal measurements, the values are statistically not significant with a p-value of 0.129. Intraclass correlation is very high, with an agreement of 0.9 and above, indicating LiDAR measurements are highly reliable and reproducible. The digital scanning system (LiDAR) is equally accurate in reproducing facial measurements compared to the conventional system, making it an excellent alternative analytical tool for taking facial measurements.