Mapping the Mandibular Lingual Foramina for Safer Chin Surgery: CT Morphometry and Predictive Modeling.

[BACKGROUND] Submental hematoma after genioplasty is rare but can be life-threatening, and current imaging data give limited patient-specific guidance for chin osteotomy design.

[METHODS] We combined targeted cadaveric dissection of two perfused heads with cranial CT analysis of 211 adults (70 long chin, 71 retrogenia, 70 controls; 621 lingual foramina). Standardized three-dimensional measurements described lingual foramen (LF) number, diameter, location, and canal trajectory, and their distances to tooth apices, genial spines, the mental foramen, and the mandibular border. Multivariable linear regression models related these metrics to facial type and chin height. Nonlinear machine learning regressors, including random forest, were trained and internally validated to predict midline LF depth.

[RESULTS] LFs clustered in the symphyseal midline, where they were larger and mainly descended toward the submental region. Facial pattern and chin height changed LF position relative to lower incisor roots but not to the inferior border. Chin height and LF-genial spine relationship were the dominant predictors in midline multivariable linear regression models (adjusted R up to 0.77). A random forest model predicted midline LF position with R 0.85 and mean absolute error 1.6 mm, close to typical surgical tolerances, and highlighted canal course, chin height, and genial spine zone as the key features; lateral predictions were weaker. Cadaveric dissection confirmed that central LFs transmit branches linking the sublingual and submental systems.

[CONCLUSION] This integrated cadaveric, CT, and modeling study defines a central high-risk corridor for chin surgery and provides interpretable, millimeter-level tools to refine osteotomy and fixation planning in aesthetic genioplasty.

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