The importance of remodeling physiological mandibular angle: mandibular "V-line" versus long curved ostectomy.

Abstract

Numerous surgical options for correcting prominent mandibular angles in East Asians have been reported. The objective of this study is to investigate the importance of remodeling physiological mandibular angle by comparing the surgical effects and complications of mandibular "V-line" ostectomy and long curved ostectomy. A retrospective study was conducted on patients who underwent either mandibular "V-line" ostectomy (Group I) or long curved ostectomy (Group II). The outcomes were evaluated using computed tomography (CT) images in combination with medical records and photographs. Data were collected preoperatively and at 6- to 12-month intervals postoperatively. Mandibular angle, posterior mandibular ramus height, radian of the ostectomy line, mandibular symmetry as well as patients' complications were investigated. FACE-Q reports of facial appearance and psychosocial parameters were also compared between the two groups. All 106 patients showed improved lower facial contours. Although the postoperative mandibular angle (116.67±7.14°vs 118.31±6.80°, P=.233) and mandibular symmetry (2.36±1.21mm vs 2.56±1.19mm, P=.395) were similar in the two groups, larger postoperative posterior mandibular height and lower radian of the ostectomy line were observed in Group I (P < .001). Physiological mandibular angle was also remodeled in Group I. The gonial deficiency, more soft tissue sagging and significant lower FACE-Q scores of facial appearance were observed in Group II (P < .001). In conclusion, "V-line" ostectomy is better suited for achieving a more physiological mandibular angle with less complications compared to mandibular long curved ostectomy. When it comes to mandibular contouring, "V-line" ostectomy may be the preferred option.