Voice Onset Time in Turkish-speaking Children with Repaired Cleft Lip and/or Palate: A Case-control Study

Abstract

Voice onset time (VOT) may be affected by deficits in laryngeal or supralaryngeal structures. This study aimed to compare the VOT parameters between the children with repaired cleft lip and/or palate (CL/P) and their healthy peers. Material and Methods: Thirty-nine children with repaired CL/P (X±SD age; 11.51±3.53 years) and 39 healthy children (X±SD age; 11.44±3.40 years) were included in the study. Clinical data including age, gender, speaking language, hearing status, type of CL/P, presence of lip/palate repairment, results of speech-sound disorder examination, and presence of malocclusion and/or oronasal fistula were retrospectively collected. VOT values for /pa/, /ta/, and /ka/ syllables were obtained using Praat software and compared between the study group (SG) and the control group (CG). Results: VOT values differed significantly between the (SG) and (CG) which were prolonged in the SG for all measured /pa/ (p=0.015), /ta/ (p=0.045), and /ka/ (p=0.037) syllables. In the SG, the longest VOT was observed for the /ka/, /ta/, and pa/ syllables, respectively. Conclusion: The presence of CL/P may have contributed to prolonged VOT values in Turkish-speaking children. Since VOT is a reliable acoustic parameter closely interacting with speech structures, clinicians should be aware of this phenomenon.