Low Cost 3D Face Scanning Based on Landmarks and Photogrammetry

Anthropometry is an objective tool serving to evaluate the shape of the face and reveal changes observed in the subject over time, or among different subjects, analyzing quantitative and qualitative differences. It also permits the study of normal and abnormal growth, diagnosis of genetic or acquired malformations, planning and evaluation of surgical and/or orthodontic therapy, and verification of the treatment results by analyzing, measuring and comparing the face shape. Among 3D digitization technologies, photogrammetry shows great promise because it is a low cost, biocompatible, safe and non-invasive methodology, but it still suffers from a need for considerable human intervention. In previous research, the Authors illustrated a new approach based on a 3-Cameras photogrammetric system. After several tests, conducted to verify the validity of this methodology, the present experimental study was carried out using a re-engineered photogrammetric scanning system to obtain landmark-models of human faces, and comparing these results with those achieved with laser scanning, applied to a dummy face (in order to eliminate errors caused by breathing movements in a living subject). Two different, specifically designed experimental 3D photogrammetric setups have been developed and tested to enhance the performance. This research demonstrates the potential of low-cost photogrammetry for medical digitization; further research will be addressed to testing the use of the scanning system on humans to validate its clinical performance.