title: Perioral soft tissue change after isolated mandibular surgery for asymmetry patients.
abstract: BACKGROUND
  This study was intended to determine whether isolated mandibular surgery for the correction of asymmetry could also change perioral soft tissue asymmetry.
  
  
  METHODS
  Skeletal class III patients who had undergone mandibular set-back surgery were included. The subjects were composed of two groups with (n = 20) or without (n = 30) menton (Me) deviation over 4 mm. The perioral lip landmarks were analyzed on three-dimensional image from cone-beam computed tomography taken before and 6 months after the operation. The bilateral and inter-group differences and pre- and post-operative changes were statistically analyzed.
  
  
  RESULTS
  The corner of mouth on the deviated side was 1.9 mm shorter vertically than that on the contralateral side in patients with asymmetry. After mandibular surgery, the deviated Me moved 5.5 mm to the contralateral side and the lip canting was corrected by 2.4° in the asymmetry group. The degree of Me deviation was significantly correlated with the degree of midline asymmetry in perioral soft tissue landmarks including subnasale, upper and lower lip midline. The predictor variable that affected the changes in lip cant was the surgical correction of Me deviation.
  
  
  CONCLUSIONS
  The correction of chin deviation by isolated mandibular surgery could significantly improve the subnasal and lip asymmetry.
authors.affiliation: Department of Oral and Maxillofacial Surgery, School of Dentistry, Kyungpook National University, Daegu 41940, Republic of Korea. Electronic address: proeg@hanmail.net.
authors.forename: Eun-Gyu
authors.initials: EG
authors.lastname: Jeon
authors.affiliation: Department of Oral and Maxillofacial Surgery, School of Dentistry, Kyungpook National University, Daegu 41940, Republic of Korea. Electronic address: st-love0907@daum.net.
authors.forename: Sung-Tak
authors.initials: ST
authors.lastname: Lee
authors.affiliation: Department of Oral and Maxillofacial Surgery, School of Dentistry, Kyungpook National University, Daegu 41940, Republic of Korea. Electronic address: kwondk@knu.ac.kr.
authors.forename: Tae-Geon
authors.initials: TG
authors.lastname: Kwon
mesh_terms: D000293:Adolescent; D000328:Adult; D059925:Anatomic Landmarks; D016022:Case-Control Studies; D054893:Cone-Beam Computed Tomography; D005146:Facial Asymmetry / Q000000981:diagnostic imaging / Q000601:surgery*; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional; D008046:Lip / Q000033:anatomy & histology; D008297:Male; D008313:Malocclusion, Angle Class III / Q000000981:diagnostic imaging / Q000601:surgery*; D009915:Orbit / Q000033:anatomy & histology; D059229:Osteotomy, Sagittal Split Ramus; D012189:Retrospective Studies; D016896:Treatment Outcome
keywords: Asymmetry; Lip cant; Mandibular surgery; Perioral; Three-dimension