Abstract
The eating characteristics of humans suggest that we are mainly adapted to the eating of vegetable matter, as judged from the relationship between the morphology and function of the temporomandibular joints and various aspects regarding their evolution from those of the other primates. The chewing style is that of careful chewing, which means chewing well.
A characteristic of the human canines is their shortness, which prevents interference with grinding movements. Human temporomandibular joints display the same movements as those of herbivores and anthropoids, the condyles are higher than those of carnivores, and humans have a well- developed ramus of the mandible. These findings indicate the morphology and function for performing careful chewing.
A correlation between the health of teeth and chewing ability was noted in this study. The correlation between healthy teeth and careful chewing habits was weak, however, and 70-80% of young people with healthy teeth had rough chewing habits. There was a slight correlation between chewing habit and chewing ability. Many people with healthy teeth and high chewing ability have rough chewing habits in their daily dietary life. This leads to a physiological in consistency between the rough chewing habits and the state of the masticatory organs that perform careful chewing.
In this study, we investigated junior high school students in northern Hyogo Prefecture as the subjects, using questionnaires, and performed a statistical comparison between the careful chewing group and the rough chewing group.
The results identified various characteristic items with regard to the health of teeth, features related to chewing habits, dietary habits, growth history, lifestyle, and psychsomatic health. These characteristic items have physical, psychological, and social content regarding health, with careful chewing reflecting good health and rough chewing poor health. These characteristic items had reliability by the linear discriminant function of multivariate analysis.
Chewing instruction to enable subjects to change from rough to careful chewing habits, as a way to improve lifestyle habits, are therefore, considered important for the improvement of the all-round health of junior high school students.
