title: Differences in soft tissue profile changes following mandibular setback in Chinese men and women.
abstract: OBJECTIVE
  This study investigated the soft tissue profile changes after surgical correction of mandibular prognathism in Chinese patients and evaluated the sex differences in the ratios of soft tissue to hard tissue change.
  
  
  METHODS
  Forty-three adult Chinese patients (18 men and 25 women) with mandibular prognathism were treated by intraoral oblique or vertical ramus osteotomy. Lateral cephalometric radiographs were taken presurgically and between 6 to 12 months postsurgically, and specific soft and hard tissue points were digitized and analyzed with a computer-aided system.
  
  
  RESULTS
  As a result of surgical setback of the mandible, the soft tissue to hard tissue change ratios were: Li:Ii = 0.71:1, Si:B = 0.90:1, Pg':Pg = 0.94:1 for the males; and Li:Ii = 0.82:1, Si:B = 0.92:1, Pg':Pg = 1.06:1 for the females.
  
  
  CONCLUSIONS
  The changes in soft tissue were closely correlated with the hard tissue movement after surgical setback of mandible. The average ratios of soft tissue to hard tissue change in horizontal direction appear to show a gender difference, which suggests the need for different ratios when predicting the results of orthognathic surgery.
authors.affiliation: Department of Oral and Maxillofacial Surgery, College of Stomatology, West China University of Medical Sciences, Chengdu, China. doctorhu@sc.homeway.com.cn
authors.forename: J
authors.initials: J
authors.lastname: Hu
authors.forename: D
authors.initials: D
authors.lastname: Wang
authors.forename: S
authors.initials: S
authors.lastname: Luo
authors.forename: Y
authors.initials: Y
authors.lastname: Chen
mesh_terms: D000328:Adult; D002508:Cephalometry / Q000706:statistics & numerical data; D002681:China; D019066:Facies; D005260:Female; D006801:Humans; D008297:Male; D008334:Mandible / Q000000981:diagnostic imaging / Q000601:surgery*; D011184:Postoperative Period; D011378:Prognathism / Q000000981:diagnostic imaging / Q000208:ethnology* / Q000601:surgery; D011859:Radiography; D011897:Random Allocation; D012727:Sex Characteristics; D013997:Time Factors