Multidimensional Severity Phenotypes in Dentofacial Deformities: Cross-Sectional Associations with Quality of Life,...

Background: Dentofacial deformities (DFDs) comprise heterogeneous sagittal, vertical, transverse, and asymmetry components, yet clinical severity is often summarized using isolated measurements. Objectives: To operationalize a reproducible composite DFD severity score and evaluate its cross-sectional associations with quality of life, function, airway-related screening indicators, and psychosocial burden. Methods: In this single-center cross-sectional study, consecutive adults assessed in an orthognathic surgery pathway underwent a prespecified 0-100 severity scoring framework integrating sagittal discrepancy (|Wits| and |ANB deviation|), vertical pattern (SN-MP angle), and asymmetry/transverse variables (chin deviation, asymmetry index, transverse discrepancy, and absolute overjet). Outcomes included the Oral Health Impact Profile-14 (OHIP-14), Orthognathic Quality of Life Questionnaire (OQLQ), FACE-Q facial appearance satisfaction scale, PHQ-9, GAD-7, STOP-Bang, functional testing, and CBCT-derived upper-airway metrics. Results: Severe DFDs had higher composite severity (62.9 ± 12.8 vs. 25.3 ± 10.9), larger sagittal discrepancy (|Wits| 6.3 ± 2.8 vs. 3.1 ± 1.8), and higher SN-MP angles (39.8 ± 7.4 vs. 34.7 ± 7.2) (all p < 0.001). Severe DFDs also had worse OQLQ (36.2 ± 6.2 vs. 24.1 ± 7.2), OHIP-14 (18.3 ± 4.2 vs. 12.4 ± 4.1), FACE-Q satisfaction (45.7 ± 10.3 vs. 67.6 ± 9.6), masticatory performance (59.4 ± 8.5 vs. 75.1 ± 7.5), and smaller airway area (126.7 ± 29.6 vs. 161.4 ± 27.7) (all p < 0.001). In multivariable logistic regression, |Wits|, SN-MP angle, asymmetry index, and lower airway area independently predicted severe status; PHQ-9 was associated with severity in unadjusted analyses but did not retain independent significance after multivariable adjustment. Model discrimination was high (AUC 0.91). Conclusions: This multidimensional severity framework captures clinically meaningful cross-sectional differences across morphologic, functional, airway-related, and psychosocial domains. Its interpretability remained stable in sensitivity analyses, but external and longitudinal validation is still required before broader implementation.