Speech production before and after orthognathic surgery: a review

A review of investigations in which speech production has been studied before and after orthognathic surgery indicates that many subjects demonstrate preoperative articulation errors. The error type most frequently identified was of the distortion variety, which suggests that misarticulating speakers were attempting to produce the sounds but that in most cases the sounds were phonetically incorrect. The /s/ speech sound and the sibilant class in general, of which /s/ is a member, were often found defective in the subjects' speech. Not all speakers had preoperative articulation errors, which suggests the possibility of compensatory articulation patterns. The literature indicates that some persons with certain occlusal and dental conditions do compensate for structural aberrations. Finally, the vast majority of subjects with preoperative misarticulations eliminated or reduced their errors following orthognathic surgery. In the case of speech behavior, it can be stated that surgical alterations in form brought about positive changes in function.