Methods: Subjects were 37 young (26.9±3.6yrs.) and 35 elderly (66.6±5.0yrs.) with normal dentition and without any history of disease concerning dysphagia. Tongue pressure during 15 ml of water was recorded at 5 locations (3 at median part, 2 at posterio-circumferential part) on the hard palate by a sensor sheet (Nitta, Tokyo, Japan) attached by the denture adhesive. Duration, maximum magnitude and impuls of tongue pressure at each location was comparerd between young and elderly groups.
Results: Duration of tongue pressure at each location in the elderly was longer than that in the young. Maximum magnitude of tongue pressure in the elderly was lower than that in the young at the median part and was higher at the posterio-circumferential parts. Although there was no difference in the inpuls of tongue pressure at the median part between two groups, impulse in the elderly was greater than that in the young at the posterio-circumferential part. These findings suggeted the age related change in the tongue movement during swallowing which might be resulted by atrophic change in tongue muscle and/or lower positioning of hyoid bone and lalynx.
Conclusions: Tongue pressure measurement using our system firstly revealed age related change in tongue movement during swallowing such as prolongation of tongue contact with hard palate and performance of larger power by the posterior part of dorsum.