The Effect of Orthognathic Surgery on the Hourglass Appearance of the Neck.

In frontal view, the transition from the upper aspect of the neck to the inferior border of the mandible has a subtle hourglass appearance. The aim of this study was to evaluate the effect of the orthognathic surgery on the hourglass appearance of the neck in patients with Class II dentofacial deformity. Twenty-six patients with Class II dentofacial deformity who underwent bilateral sagittal split osteotomy alone or in combination with Le Fort I osteotomy and/or genioplasty were included in this study. The width of the most upper part, the width of the narrowest part, the length of the upper part, the height of the upper part, the depth, and the angle of the hourglass were measured on frontal facial photographs obtained preoperatively and at sixth months postoperatively. The decrease in the width of the narrowest part ( P =0.012) and the right ( P <0.001) and left ( P <0.001) angles of the hourglass were statistically significant. Also, increase in the right ( P =0.036) and the left ( P =0.004) depths of the hourglass were statistically significant. Orthognathic surgery procedures performed to correct Class II dentofacial deformity positively affects the hourglass appearance of the neck, therefore neck esthetics should also be considered in the preoperative evaluation of facial esthetics.