[Principal component analysis of the masticatory motion path during gum chewing]

This study examined the characteristics of masticatory motion path using multivariate analysis. Principal component analysis was selected as the method and various important results were revealed as follows; Approximately 70% of the information describing gum chewing motion was explained by three principal components. From factor loading, the first principal component explains back and forth movement from the end of the opening phase to the closed position, the second principal component explains left to right movement at the onset of the mouth opening phase, and the third principal component explains left and right movement at about the position of maximum opening. Using scatter diagrams combining the first and second principal components, as well as the first and third principal components, we were able to recognize delicate differents among the subjects, but to the different strokes of any subject, characteristic patterns were emerged.