The effects of orthognathic surgery on speech: a review.

Purpose: To assess the effects of orthognathic surgery on speech in non-cleft individuals.

Materials And 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.

Conclusion: 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.