Outcome Analysis of Extended, Long, Curved Ostectomy with Outer Cortex Grinding for Prominent Mandibular Angle and Broad Chin to Achieve V-line Contouring

ABSTRACT

BACKGROUND: In Asian countries, patients with a square-shaped lower face want a narrow chin as well as improvements in the mandibular angle contour, which is called a "V-line shape." Currently, various surgical techniques have been developed for mandibuloplasty. METHODS: We have developed an extended, long, curved ostectomy, which starts from the inferior mandibular margin below the lateral incisor to the angle, using reciprocating and oscillating saws. We also used a small round bur to grind the outer cortex of the chin and ramus. A total of 243 patients were included in this study from 2012 to 2014. RESULTS: To analyze aesthetic outcomes, we compared mandibular angles and gonial-gonial (G-G) distances on preoperative three-dimensional computed tomography scans with postoperative images. Mandibular measurements demonstrated significant increments in angle degrees on the right (115.2degrees+/-11.1 vs 129.3degrees+/-11.5, P<0.05) and left sides (112.2degrees+/-10.2 vs 130.4degrees+/-11.3, P<0.05). The G-G distance was reduced postoperatively from 123.7 mm+/-7.9 to 110.0 mm+/-3.5 (P<0.05). CONCLUSIONS: In this study, we demonstrate the effectiveness of our technique and assume that we can improve frontal shape and lateral contour with its use.