Abstract
In order to investigate the effect which the consistency of the food has on the masticatory path, 78 normal subjects were asked to chew boiled fish paste, chewing gum, peanuts, and beef jerkey. The path pattern, the amount of opening, and the width of mastication were investigated using an automatic masticatory movement analyzing system, and the following results were obtained.
1. The two patterns, pattern I (smooth opening toward the working side, and convex closing) and pattern ifi (opening toward working side after initially toward non-working side and convex closing) constitute the majority of the patterns observed.
2. In the group which showed pattern I in chewing boiled fish paste, the most frequent case was pattern I in all other three food.
3. In the group which exhibited pattern III in chewing boiled fish paste, the majority cases showed pattern DI in all other three food also.
4. The amount of jaw opening and the width of mastication increased with the hardness of the food.
5. It is suggested that although the path of mastication varies as the type of food changes from soft to hard, the majority of the path pattern can be represented by patterns I and III in normal subjects. Also, though there are cases which relate pattern I to soft food and pattern III to hard food, basically the consistency of the food does not affect path patterns.
