The utility of a three-dimensional approach with T-shaped osteotomy in osseous genioplasty

Abstract

Background: Facial beauty depends on the form, proportion, and position of various units of the face. In terms of the frontal view and facial profile, the chin is the most prominent aesthetic element of the lower third of the face. Many methods have been implemented to obtain good proportions of the lower face. In this study, we applied the T-shaped genioplasty method to correcting chin deformities.

Methods: All of the procedures in 9 cases were performed under general anesthesia. For genioplasty, a horizontal cutting line and 1 or 2 vertical cutting lines were drawn 5 mm below the mental foramen. Osteotomed bone segments of the chin were used for horizontal widening using bone grafts or for horizontal shortening. Likewise, they were used as bone grafts for vertical lengthening or vertical shortening. The bone segments were approximated in the midline and held in place using miniplates.

Results: The postoperative appearance of the 9 cases showed that the lower third of the face had been naturally changed. At the same time, vertical lengthening or shortening, and horizontal widening or shortening could be implemented during the operation. Satisfactory results were obtained based on reviews of the patients' preoperative and postoperative photographs. The patients were also satisfied with the outcomes.

Conclusions: Using T-shaped genioplasty, we efficiently adjusted the shape and position of the chin to obtain good proportions of the lower face and change its contour to obtain an aesthetically appealing oval face in accordance with East Asians' aesthetic preferences.

Keywords: Chin; Genioplasty; Mandibular osteotomy.

Fig. 1

Schema of preoperative 3D skull modeling For 3-dimensional (3D) correction of the chin, we designed the schema for the surgical methods using 3D Studio MAX, a 3D computer modeling tool. We then cut the preoperative 3D skull model along the designed schema. (A) Schema for surgical methods of horizontal (red arrow) and vertical shortening (blue arrow head) plus backward movement (blue arrow) after T-shaped osteotomy. (B) Schema of surgical methods of horizontal widening (red arrow) and vertical lengthening (blue arrow head) plus forward movement (blue arrow) after T-shaped osteotomy. (C) Schema of surgical methods of horizontal shortening (red arrow) and vertical widening (blue arrow head) with a bone graft (blue) after T-shaped osteotomy.

Fig. 2

Intraoperative view of T-shaped genioplasty (A) Horizontal widening and vertical lengthening was performed with an iliac bone graft after T-shaped osteotomy. (B) Horizontal shortening and vertical lengthening was performed with an angle bone graft after T-shaped osteotomy.

Fig. 3

Preoperative and postoperative 3D CT of patient Horizontal shortening and vertical lengthening was performed with an angle bone graft after T-shaped osteotomy. (A) Preoperative 3-dimensional (3D) computed tomography (CT). (B) Six months postoperative 3D CT.

Fig. 4

Case 1: preoperative and postoperative photographs Horizontal and vertical shortening, backward movement was done after T-shaped osteotomy. (A) Preoperative photograph with a lateral view. (B) Photograph 6 months postoperatively with a lateral view.

Fig. 5

Case 2: preoperative and postoperative photographs Horizontal widening and vertical lengthening was performed with an iliac bone graft after T-shaped osteotomy. (A) Preoperative photograph with a lateral view. (B) Photograph 6 months postoperatively with a lateral view.

Fig. 6

Case 3: preoperative and postoperative photographs Horizontal shortening and vertical widening was performed with an angle bone graft after T-shaped osteotomy. (A) Preoperative photograph with a frontal view. (B) Preoperative photograph with a lateral view. (C) Photograph 6 months postoperatively with a frontal view. (D) Photograph 6 months postoperatively with a lateral view.