Abstract
The purpose of this study was to investigate the influence of the vertical dimension of dentures on pronunciation.
The results were as follows:
1. The maximum tongue pressures tended to be greater in more posterior palate in the normal vertical dimension, just as in normal subjects.
2. The maximum tongue pressures tended to decrease in anterior palate and increase in posterior palate with increases in vertical dimensions, just as in normal subjects. But, conversely, some of them had a tendency peculiar to complete denture wearers to increase in anterior palate for sounds /asa/, /asi/, etc.
3. Tongue contacts usually started from posterior palate to anterior palate in the normal vertical dimension, just as in normal subjects. But the timings between sounds and tongue pressures weren't consistent with increases in vertical dimensions.
4. The incisor position of mandible tended to be downward and back with a decrease in vertical dimension, and to be located differently with increases in vertical dimensions, just as in normal subjects.
5. Changes in maximum tongue pressures with varying vertical dimensions were related to those of simultaneous mandibular movements, just as in normal subjects. In some cases, including/asa/ and /asi/, a correspondence peculiar to complete denture wearers was found.
