title: Soft-tissue changes after maxillomandibular advancement surgery assessed with cone-beam computed tomography.
abstract: BACKGROUND
  The purpose of this study was to quantify anteroposterior and transverse facial soft-tissue changes with respect to underlying skeletal movements after maxillomandibular advancements by using cone-beam computed tomography.
  
  
  METHODS
  Thirty white patients were treated by maxillomandibular advancements after LeFort I osteotomies and bilateral sagittal split osteotomies. The patients were scanned by using cone-beam computed tomography within 1 week before the surgery, within 1 week after the surgery, and a minimum of 8 weeks postsurgery. We measured the differences between the first and last images and calculated ratios for anteroposterior and transverse soft-to-hard tissue movements. Changes in the greatest interalar width were also measured.
  
  
  RESULTS
  There was a statistically significant difference in the greatest interalar width change between patients receiving maxillary advancements greater than 4 mm and those having advancements less than or equal to 4 mm (P <0.023). Mean ratios of anteroposterior soft-to-hard tissue movements were 84.9% +/- 38.0% in the malar region, 96.1% +/- 15.5% in the chin, and 101.1% +/- 27.3% in the subcommissural region. Mean ratios of transverse soft-to-hard tissue movements were 39.4% +/- 19.7% in the malar region and 82.5% +/- 56.7% in the subcommissural region.
  
  
  CONCLUSIONS
  The amount of maxillary advancement most likely plays a role in the postsurgical increase in interalar width. In addition, facial soft tissues appear to respond more to anterior movement of the jaws than to an increase in transverse dimensions after maxillomandibular advancements.
authors.affiliation: Department of Orthodontics, Saint Louis University, St. Louis, MO 63104, USA.
authors.forename: Michael S
authors.initials: MS
authors.lastname: Ryckman
authors.forename: Steven
authors.initials: S
authors.lastname: Harrison
authors.forename: Don
authors.initials: D
authors.lastname: Oliver
authors.forename: Christian
authors.initials: C
authors.lastname: Sander
authors.forename: Andrew A
authors.initials: AA
authors.lastname: Boryor
authors.forename: Ansgar A
authors.initials: AA
authors.lastname: Hohmann
authors.forename: Fatih
authors.initials: F
authors.lastname: Kilic
authors.forename: Ki Beom
authors.initials: KB
authors.lastname: Kim
mesh_terms: D000293:Adolescent; D000328:Adult; D002508:Cephalometry / Q000379:methods; D054893:Cone-Beam Computed Tomography; D005145:Face / Q000033:anatomy & histology* / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional; D008297:Male; D008310:Malocclusion / Q000601:surgery; D019186:Mandibular Advancement; D008437:Maxilla / Q000601:surgery*; D008875:Middle Aged; D019340:Osteotomy, Le Fort; D017063:Outcome Assessment, Health Care; D011184:Postoperative Period; D012984:Software; D018709:Statistics, Nonparametric; D055815:Young Adult