Sex-Specific Facial-Soft-Tissue Morphology in Mandibular Prognathism

This study aimed to evaluate sex differences in facial soft tissue morphology in patients with mandibular prognathism and to assess treatment outcomes while considering these differences. It included 30 patients (15 males and 15 females) with skeletal mandibular prognathism who underwent bilateral sagittal split ramus osteotomy (SSRO), along with a control group of 30 healthy volunteers (15 males and 15 females). Three-dimensional facial data were collected, and homologous modeling was used to analyze facial morphology. Qualitative and quantitative analyses were performed using principal component analysis (PCA), analysis of variance (ANOVA), and Tukey's test. The results showed that males had greater facial height and a longer chin, whereas females had a smaller chin and a more rounded zygomatic-cheek area. In male patients, postoperative facial morphology approached that of healthy males. However, female patients retained masculine facial features such as midface flatness and increased facial height, even after surgery. These findings suggest that surgical intervention in the midface and chin regions may be necessary for female patients to improve facial esthetics and satisfaction, even when occlusion is properly corrected. This study highlights the importance of considering sex differences in facial soft tissue morphology when planning orthognathic surgery for patients with mandibular prognathism.