The pattern of tongue pressure against the palate during articulating glossal sounds in normal subjects and glossectomy patients

The purpose of the present study was to measuretongue pressure with the aim of characterizingthe pattern of linguopalatal contact during articulatingglossal sounds in normal subjects andglossectomy patients. Tongue pressures againstthe palate were evaluated in 13 normal subjectsand 5 glossectomy patients by using three parameters:the duration from the onset of linguopalatalcontact to the time of maximum pressure,the maximum pressure, and anterior posteriorratio of the maximum pressure. Three glossalsounds, [ti], [tʃi], and [ʃi], which have tendency ofmishearing in glossectomy patients, were selectedfor test sounds. A unique characteristic wasdemonstrated in normal subjects. The score of themaximum pressure showed an apparent orderamong the three sounds, while the durationsrevealed the opposite order. Anterior posteriorratio of the maximum pressure also showed somerelationship among three sounds. In glossectomypatients, these characters were not found. Theloss of tongue volume or deterioration of tonguemobility causes these results.