Journal of Dental Research, Vol 76, 796-806, Copyright © 1997 by International & American Associations for Dental Research Online Journals
Evidence of sex-specific differences in masticatory jaw movement patterns
G. E. Gerstner and V. V. Parekh
Department of Biologic and Materials Sciences, University of Michigan, Ann Arbor 48109-1078, USA.
The complexity of human oral functional movements has not been studied in
detail quantitatively, and only recently have studies begun to evaluate
whether such movements contain sex-specific characteristics. Therefore, the
purposes of this study were: (1) to quantify in detail the jaw movements
and associated masticatory electromyographic activity occurring during gum
chewing, and (2) to explore these data for evidence of sex specificity.
Fourteen male and 17 female subjects participated in the study.
Approximately 11 right- and 11 left-sided chewing cycles and associated
masticatory electromyographic activity were sampled from each subject. The
samples were quantified into 165 variables per chewing cycle, averaged to
create a single multivariate vector for each subject, and then analyzed by
a step-wise discriminant analysis. With a combination of 6 variables, a
jackknifed cross-validation test found the probability of correct
classification to be 93.5%. These findings support the hypothesis that
masticatory jaw movements contain sex-specific features.
