Abstract
The purpose of this experiment was to clarify the most suitable chewing time for evaluating the masticatory efficiency of gumi jelly chewing.
Twenty healthy subjects in their twenties, 10 males and 10 females, average age 25.2, who were aware of their habitual chewing side and had neither systemic nor masticatory abnormalities, were selected. Informed consent was obtained after the general nature of the study had been explained to the subjects. The test bolus was a cylinder shaped gumi-jelly, 1.5cm in diameter and 0.8cm in height, weighing approximately 2g. The amount of glucose extraction while chewing gumi-jelly for each of 5, 10, 15, 20 and 25 seconds (5 sessions) was calculated by using a glucosemeasuring device. First, the relation between the chewing time and the amount of glucose extraction was investigated. Next, the amount of glucose extraction for each session was converted to the amount that would be released in 25 seconds of chewing, and was standardized to the average of the five sessions, and the results were compared among each other.
The amount of glucose extraction of each session increased as the chewing time increased and a highly significant correlation was found (r=0.873, p<0.01) . The average value of the amount of glucose extraction after standardization was close to one for every session, and the standard deviation was also small. The coefficient of variation of the amount of glucose extraction for each session was smallest for the 15-second session, and increased in the order of 20 sec, 10 sec, 25 sec, and 5 sec. The value for the 20-second session was very close to that of the 15-second session.
From these results it was suggested that the amount of glucose extraction during gumi jelly chewing increased in relation to the amount of masticatory work done, and that the suitable chewing time for evaluating the masticatory efficiency in gumi jelly chewing was 15 or 20 seconds.
