ABSTRACT
OBJECTIVES: The purpose of this study was to determine how use of the vocal facilitating technique, chewing, affected the phonation of speech-language pathology (SLP) students. STUDY DESIGN: A pretest-posttest randomized control group design was used. METHODS: Twenty-seven healthy female SLP students were randomly assigned into either an experimental group or a control group. The experimental group practiced chewing exercises across 18 weeks, whereas the control group received no vocal facilitating techniques. Both groups completed pre- and post- objective voice assessment measures (aerodynamic measurement, acoustic analysis, voice range profile, and Dysphonia Severity Index). Differences between pre- and post-data were compared between the experimental and control group using an independent sample t test. RESULTS: Compared to the control group, chewing resulted in a significant decrease in jitter and noise-to-harmonic ratio (NHR), a significant increase in fundamental frequency (fo), a significant expansion of the voice range profile, and a significant increase in Dysphonia Severity Index (DSI). Shimmer and maximum phonation time (MPT) were not significantly different between groups. CONCLUSIONS: The results of this pilot study suggest that the vocal facilitating technique, chewing, may improve objective vocal measures in healthy female SLP students.
