This study was carried out to examine the changes in chewing pattern during mastication of chewing gum with four hard materials. Each hard material was granular but varied in size and hardness. Recording and analysis of chewing movement was performed in 9 males and 6 females without stomatognathic dysfunction by using Sirognathograph Analyzing System III.
The results were as follows:
1. The typical changes in the chewing pattern were classified into two groups:
1) the terminal position of mastication when contacting or crushing a hard material coincided with the inherent terminal position.
2) the terminal position of mastication did not coincide with the inherent terminal position.
2. The process of mastication of the testing gum with a hard material was divided into five phases by changes in chewing patterns.
3. The changes in chewing patterns were different among the hard materials.
