title: The effects of orthognathic surgery on speech: a review.
abstract: OBJECTIVE
  To assess the effects of orthognathic surgery on speech in non-cleft individuals.
  
  
  METHODS
  A literature survey was undertaken using the Medline (Entrez Pubmed) and EMBASE databases (1966 to 2006). Key orthodontic, orthognathic, and speech journals were also hand searched. No language limitations were imposed. Randomized controlled trials, prospective and retrospective longitudinal trials (with and without controls), and case series were considered for inclusion.
  
  
  RESULTS
  Eighteen studies were identified as fulfilling the inclusion criteria. Controls were used in one fifth of the trials; 13 articles reported preoperative articulation errors. In 8 of the trials, speech articulation either improved or was corrected for the majority of individuals assessed. In the studies assessed, the type of surgery or degree of movement did not appear to affect speech.
  
  
  CONCLUSIONS
  There is no clear evidence directly relating malocclusions to speech discrepancies. Furthermore, it is difficult to draw any firm conclusions with respect to the effect of orthognathic surgery on speech. Further investigation is required.
authors.affiliation: Maxillofacial Unit, St George's Hospital and Medical School, London, UK.
authors.forename: Tasnim
authors.initials: T
authors.lastname: Hassan
authors.forename: Farhad B
authors.initials: FB
authors.lastname: Naini
authors.forename: Daljit S
authors.initials: DS
authors.lastname: Gill
mesh_terms: D001184:Articulation Disorders / Q000209:etiology* / Q000503:physiopathology; D003131:Combined Modality Therapy / Q000009:adverse effects; D006801:Humans; D008310:Malocclusion / Q000150:complications*; D019647:Oral Surgical Procedures / Q000009:adverse effects*; D009971:Orthodontics, Corrective / Q000009:adverse effects; D056948:Orthognathic Surgical Procedures