The Effects of Palate Features and Glossectomy Surgery on /s/ Production

The aims of this article were to determine the effects of hard palate morphology and glossectomy surgery on tongue position and shape during /s/ for patients with small tumors. The first expectation was that laminal /s/ would be more prevalent in patients, than apical, due to reduced tongue tip control after surgery. The second was that patients would hold the tongue more anteriorly than controls to compensate for reduced tongue mass.

Three-dimensional tongue volumes were calculated from magnetic resonance imaging for the whole tongue and the portion anterior to the first molar during the /s/ in /əsuk/ for 21 controls and 14 patients. These volumes were used to calculate tongue anteriority and cross-sectional shape. Dental casts were used to measure palate perimeter, height, and width of the hard palate.

Palate height correlated with tongue height in controls (p < .05), but not patients. In patients, tongue anteriority correlated negatively with canine width and cross-sectional tongue shape (p < .05). Controls with a high palate favored laminal /s/. Patients preferred laminal /s/ regardless of palate height (p < .01).

For controls, hard palate height affected tongue height; a higher palate yielded a higher tongue. For patients, hard palate width affected tongue width; a narrower palate yielded a more anterior tongue. Tongue shape was unaffected by any palate features. Preference for /s/ showed an interaction effect between subject and palate height. Controls with high palates preferred a laminal /s/. All patients preferred a laminal /s/; glossectomy surgery may reduce tongue tip control.