Tongue-palate contact during selected vowels in children with cleft palate

This study reports tongue-palate contact recorded using electropalatography (EPG) during five vowels /i/, /theta/, /I/, /o/ and /backwards c/ spoken by school-aged children with cleft palate and a group of normal speakers. All the children had articulation disorders affecting consonants but none had obvious vowel errors. Two measures were taken from the EPG data at the temporal midpoint of the vowels. The first identified the percentage of vowels produced with complete coronal constriction and the second calculated amount of contact. The results showed that children with cleft palate frequently produced the high vowel /i/ with complete constriction, with 40% of /i/ targets articulated in this way. There were lower percentages for /theta/ and /I/ and no complete constrictions during the lower vowels /o/ and /backwards c/. None of the normal speakers produced any vowels with complete constriction. In terms of amount of contact, the vowels ranked /i/>/theta/>/I/>/o/>/backwards c/, with /i/ having the most and /backwards c/ the least contact. Although this ranking held for both groups, the cleft group had more contact than normal speakers, especially during high vowels. Complete constriction is viewed as a clinically relevant phenomenon that blocks oral airflow and as a result increases nasal airflow during vowels.