Newly developed sensor sheet for measuring tongue pressure during swallowing

Purpose: The aim of this study was to develop a sensor sheet for measuring tongue pressure during swallowing and to clarify its usefulness by comparing it with a conventional pressure sensor installed in the palatal plate. Methods: A tactile sensor system was used for the construction of the measuring system. Based on our preceding study, a T-shaped sensor sheet with 0.1 mm thickness, five measuring points (three points on the median line, two points on the posterior-lateral part) and three sizes based on the morphological analysis of 60 maxillary casts was designed for application on the hard palate. To elucidate the sensing characteristics of the sensor sheet, the output level of the sensor sheet was compared with that of a conventional pressure sensor under the same load. The maximal magnitude of tongue pressure (MP) during the swallowing of 15 ml water was recorded by a sensor sheet attached to the palatal mucosa and was compared with that recorded by pressure sensors installed in the palatal plate. Results: The output level of the sensor sheet was smaller than that of the pressure sensor. There was a high correlation between the output levels of the two sensors (R = 0.952, P < 0.001). Although MP at each sensing point of the sensor sheet was also smaller than that recorded by the pressure sensors, MP collected by the regression equation obtained in our experiment was quite similar to that for the pressure sensors. Conclusions: This system could be useful for evaluating tongue activity during oropharyngeal swallowing. (C) 2009 Japan Prosthodontic Society. Published by Elsevier Ireland. All rights reserved.