3D Facial Normotypes for Maxillofacial Surgical Planning

Background: Preoperative planning in maxillofacial and orthognathic surgery requires anatomical references to guide the definition of functional and aesthetic treatment objectives. Currently available planning tools do not provide quantitative, clinically interpretable three-dimensional morphological targets that are tailored to patient's sex- and geography-specific characteristics. This study proposes a methodological pipeline for the development of sex-specific 3D facial normotypes in a population of healthy, normal-weight Caucasian young adults to serve as a reference for maxillofacial surgery planning. Methods: The approach is based on the integration of validated anthropometric references with three-dimensional data acquired using 3D scanners. Semi-automatic landmarking was performed on the acquired faces, and a comprehensive set of literature-acknowledged morphometric features and related reference ranges were extracted; a multivariate statistical analysis was applied. Results: The final collected database comprised 109 Caucasian subjects (70 females, 64.2%) that served as a quantitative basis for designing a female and male facial normotype in the form of 3D models. The developed normotypes showed high agreement with the literature-based reference ranges, reaching 95% for the male model and 91% for the female model. Conclusions: This study proposes a methodological approach integrating classical anthropometry with 3D digital modeling. The resulting normotypes represent consistent morphological face models and provide a quantitative and morphologically interpretable reference framework. This framework may support the future development of interactive tools and quantitative assessment metrics for surgical planning. However, its clinical applicability has not yet been validated, and further studies are required to assess its reliability and potential utility in surgical planning.