Juicy fresh gum had been used for measuring the masticatory ability, but manufacturing it stopped, and consequently the selection of substitutive gum became objective. Five kinds of gums were tested as the gum for measuring the masticatory ability and xylitol gum for dentist was the most appropriate. In the case of chewing frequency of 20-60, amount of elution sugar increased proportionally to chewing frequency with the correlation coefficient of R²=0.9946. Also, chewing time increased proportionally to chewing frequency with the correlation coefficient of R²=0.998. Appropriate chewing frequency in measuring masticatory ability using xylitol gum for dentist was 40, which lies middle within the range of 20-60 frequency with proportional relationship between chewing frequency and elution sugar amount. Therefore it is possible to measure the masticatory ability by the use of this gum. Such a result could not be obtained using other gums.
In fact, when the masticatory ability was measured for first grade student in senior high school using xylitol gum for dentist, almost the same form with normal distribution was found for the relationship between amount of elution sugar and number of persons. Moreover, there was the significance at elution sugar amount between boys and girls pupils. In other words, group with strong masticatory ability had 21 persons (16.7%). Group with normal masticatory ability had 85 persons (67.5%) and one with weak masticatory ability had 20 persons (15.9%). These are same results as those in the cases of using juicy fresh gum and accordingly, xylitol gum for dentist can be used for measuring the masticatory ability instead of juicy fresh gum the production of which was abandoned.