Purpose
to investigate whether lisp, when identified, differs between voiced and unvoiced alveolar fricatives produced by children with cleft palate.
Methods
a prospective study in which sentences comprising the consonants [s] and [z] produced by 32 children with cleft palate (mean age, 8 years, 8 months) were selected and after auditory judged. All children presented altered inter-relationship arches as evaluated by three orthodontists (inter-judge agreement almost perfect kappa = 0.81), performing analysis of dental casts. Three Speech-Language-Pathologists judged perceptually audio recorded productions. The inter-judges agreement ranged between 56% and 78% and between 59% and 93% for the phrases consisting of [s] and [z], respectively.
Results
the lisp was identified in 69% of children, particularly, in 72% and 50% [s] and [z] sounds, respectively. There were significant differences between judgments for the fricatives [s] and [z], with higher prevalence of lisping in [s].
Conclusions
dentofacial deformities may favor the occurrence of lisp in population with cleft palate. The increased occurrence of lisp in [s] compared to [z], based on auditory perceptual identification, can be justified by acoustic and / or articulatory reasons. It is suggested that lisp is dependent of the phonetic-phonological context of the sentence and therefore must be considered for clinical and research purposes.
Speech; Cleft Palate; Malocclusion