[Influence of glottal stops on nasalance and velopharyngeal closure status after cleft palate surgery]

Objective: To investigate the influence of glottal stops for the relationship between nasalance and velopharyngeal closure status of cleft palate patients after surgery. Methods: A total of 71 patients with postoperative cleft palate speech disorders treated in the Department of Oral and Maxillofacial surgery, School of Stomatology, Peking University from August 2004 to August 2010 were included. The compensated speech evaluation of cleft palate with or without glottic occlusion was performed in 50 males and 21 females with an average age of (15.9±6.2) years old. The nasal sound meter and nasopharyngeal fiber endoscope were used to record the nasal phonation rate and the score of nasopharyngeal fiber endoscopic visual analog scale (VAS) of the patients. According to the results of glottic plug speech evaluation, the patients were divided into three groups: whole group (without glottic plug), glottic plug group and silent glottic plug group. The nasal phonation rate values and VAS values of 11 speech samples (unit vowel No. 1-3, continuous syllable No. 4-9, sentence 10-11) of the three groups were compared by Pearson analysis. Results: There were 71 patients in the whole group, 34 patients in the glottic plug group and 37 patients in the silent glottis group. There was a negative correlation between nasal phonetic rate and VAS of 11 speech samples in the whole group, however there were no significant difference (r>-0.179 and<-0.017, P>0.017) and no significant correlation between nasal phonetic rate and VAS in glottic occlusion group (r>-0.196 and<-0.017, P>0.05). There was a significant negative correlation between nasal phonetic rate and VAS value of all but No. 1, 3 and 11 speech samples in silent door plug group (P<0.05), among which No. 7 speech sample was the most sensitive sample (r=-0.557, P<0.05). Conclusions: The present study showed the glottal stops could affect the evaluation of the velopharyngeal closure function by using nasometer. Glottal stops should be considered as one important factor for the nasalance.