Journal of Dental Research, Vol 80, 2030-2034, Copyright © 2001 by International & American Associations for Dental Research Online Journals
Kinematic modeling of jaw-closing movement during food breakage
K. Yashiro, M. Fujii, O. Hidaka and K. Takada
Department of Orthodontics and Dentofacial Orthopedics, Graduate School of Dentistry, Osaka University, Suita, Japan.
It has been demonstrated that the vertical jaw movement trajectories during
gum-chewing can be explained by jerk-cost minimization. However, it is
uncertain whether the masticatory jaw movement in space can be predicted by
the minimum-jerk model. The aims of the present study were to develop
minimum-jerk models that would explain 3D masticatory jaw movements with
different hardnesses of foods, and to evaluate if the models can predict
the movements accurately. The 3D masticatory jaw movement during food
breakage was formulated for two types of test foods. The coefficients of
determination (R2) between the measured and model-based values ranged from
0.846 to 0.882. Differences were found in the kinematic parameters between
the test foods. The results suggest that the models predict the 3D jaw
movements during food breakage and are effective in differentiating among
the kinematic features of masticatory jaw movements that are peculiar to
the mechanical properties of foodstuffs.
