Speech errors associated with dentofacial abnormalities in Cantonese speakers

Abstract

The aim of this study was to document the effect of dentofacial abnormality on speech. Subjects were 33 Cantonese speakers (15 men and 18 women; age 15 to 40 years). Dento-skeletal measures were made for each patient. Speech assessment included voice (perceptual), resonance (perceptual and instrumental), and articulation. Articulation assessment involved narrow transcription of a screening test and a deep test. Errors were classified following Vallino (1990). Over half the speakers (57.57%) had at least one error on the articulation screening test and 66.66% had errors on the deep test. The most vulnerable phonemes were /f/, /s/, /ts/, and /tsh/; most errors were distortions. Error patterns were consistent within speakers. Several unusual error patterns were noted (e.g., affrication, bilabial fricative), which were considered related to Cantonese phonology. There was no significant difference in speech accuracy by dentofacial variables.