Enriching the virtual twin: clinical benefits of facial scan integration in orthognathic surgery planning

The aim of this report was to present a reproducible workflow for integrating three-dimensional (3D) facial scans into computed tomography-based virtual surgical planning of orthognathic surgery, thereby enriching the virtual twin with clinically relevant soft-tissue information. This report describes the sequential stages of the workflow: 1) standardised preoperative imaging including computed tomography, intraoral scans (IOS), and three facial scans (rest, smile, lip-retracted); 2) preprocessing of facial scans in 3-Matic to remove dental structures and generate soft-tissue stereolithography (STL) models; 3) virtual twin construction in Materialise Enlight v7.0 by integrating digital imaging and communications in medicine skeletal data, IOS, and surface-based facial models; 4) application of repositioning tools and STL import functions to integrate multiple facial scans; 5) visualisation and analysis of natural head position, digital smile design, and comparison of pre- and postoperative soft-tissue predictions; and 6) finalisation of the case with the generation of intermediate and final splints and export of all planning data. The integration of facial scanning into virtual surgical planning is feasible and may be clinically relevant. While promising, further validation is required to confirm accuracy and reproducibility in routine clinical practice, particularly with respect to natural head position, digital smile design, and soft-tissue prediction. This workflow highlights the potential of recent software advances and facial scanning technologies in orthognathic planning.