title: Soft tissue profile changes after bilateral sagittal split osteotomy for mandibular advancement: a systematic review.
abstract: OBJECTIVE
  The purpose of the present systematic review was to evaluate the soft tissue/hard tissue ratio in bilateral sagittal split advancement osteotomy (BSSO) with rigid internal fixation (RIF) or wire fixation (WF).
  
  
  METHODS
  The databases PubMed, Medline, CINAHL, Web of Science, Cochrane Library, and Google Scholar Beta were searched. From the original 711 articles identified, 12 were finally included. Only 3 studies were prospective and 9 were retrospective. The postoperative follow-up ranged from 3 months to 12.7 years for RIF and 6 months to 5 years for WF.
  
  
  RESULTS
  The short- and long-term ratios for the lower lip to lower incisor for BSSO with RIF or WF were 50%. No difference between the short- and long-term ratios for the mentolabial-fold to point B and soft tissue pogonion to pogonion could be observed. It was a 1:1 ratio. One exception was seen for the long-term results of the soft tissue pogonion to pogonion in BSSO with RIF; they tended to be greater than a 1:1 ratio. The upper lip mainly showed retrusion but with high variability.
  
  
  CONCLUSIONS
  Despite a large number of studies on the short- and long-term effects of mandibular advancement by BSSO, the results of the present systematic review have shown that evidence-based conclusions on soft tissue changes are still unknown. This is mostly because of the inherent problems of retrospective studies, inferior study designs, and the lack of standardized outcome measures. Well-designed prospective studies with sufficient sample sizes that have excluded patients undergoing additional surgery (ie, genioplasty or maxillary surgery) are needed.
authors.affiliation: Department of Orthodontics and Oral Biology, Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands. christofjoss@hotmail.com
authors.forename: Christof Urs
authors.initials: CU
authors.lastname: Joss
authors.forename: Isabella Maria
authors.initials: IM
authors.lastname: Joss-Vassalli
authors.forename: Stavros
authors.initials: S
authors.lastname: Kiliaridis
authors.forename: Anne Marie
authors.initials: AM
authors.lastname: Kuijpers-Jagtman
mesh_terms: D002508:Cephalometry; D002680:Chin / Q000601:surgery; D002986:Clinical Trials as Topic; D057225:Data Mining; D005145:Face / Q000033:anatomy & histology*; D006801:Humans; D019248:Jaw Fixation Techniques; D008046:Lip / Q000033:anatomy & histology; D008334:Mandible / Q000601:surgery; D019186:Mandibular Advancement / Q000379:methods*; D056948:Orthognathic Surgical Procedures / Q000379:methods*; D010027:Osteotomy; D012008:Recurrence; D012189:Retrospective Studies; D013223:Statistics as Topic