Effects of increased vertical dimension on size of constriction port and fricative sound intelligibility

Abstract

The effect of increased vertical bite dimension on fricative sound productions was studied in five adults who wore dentures. Oral port size and sound intelligibility were evaluated at different degrees of artificially induced open bite. The data demonstrate that rapid compensatory adjustments occurred and oral port size changed minimally at all degrees of opening tested. However, in three of the subjects, sound intelligibility declined at the 6-mm opening, and in all subjects, a four-fold increase in sound distortions occurred in the edentulous state. This finding suggests the possibility that either physiological parameters are controlled more successfully than acoustical parameters or that compensatory efforts to maintain constrictor size may, under certain circumstances, adversely affect sound intelligibility.

Perceived Oral Opening and Lip/Jaw Displacement during Speech

“…1976;Smith et al, 1978;Warren et al. 1984;Warren et al. 1980] have exam ined oral opening during consonants (e.g., /s/, /p/) or during vowels other than Ixl and lal.…”

Physiologic and Perceptual Effects of Induced Anterior Open Bite

“…Immediately following the taping sessions, the constriction port between the tongue and palate was measured using the aerodynamic technique reported by Warren et al [1980], As the subjects spoke, differ ential pressure across the port and oral airflow were recorded simultaneously. Measurement of pressure was made at the point of maximum amplitude for the selected phoneme.…”

“…In recent reports Warren et al [1980Warren et al [ . 1981 have suggested that, under conditions of induced open bite or open bite malocclu sion.…”

“…The present study is an extension of our previous investigations of compensatory strategies in response to changes in the oral environment [KlechakcX al., 1976;Warren et al, 1980Warren et al, . 1981, These studies, involving fri cative sounds in isolation and in carrier phrases, demonstrated good structural adap tation but poor speech performance.…”

Respiratory Responses to Sudden Pressure Venting during Stop Consonant Production

“…Recent studies [7][8][9][10][11][12][13][14][15][16] suggest that several factors may influence the respiratory response to VPI. To illustrate, in a study [14] comparing data from bite-block and bleed-valve experiments with data from individuals exhibiting VPI, it was shown that the differences in intraoral pressures associated with increased pressure venting reflect the capability of the speech system to utilize available articulatory and respiratory adjustments to stabilize the aerodynamic environment.…”