Forces exerted by masticatory muscles. Only the orientation of the forces of the right side are given (symmetry with respect to the sagittal plane was assumed). The magnitude of the muscle force peak in CO for the ipsilateral (I) and contralateral (C) sides are also provided. The +x-axis is directed anteriorly, the +y-axis rightward, and the +z-axis downward. CP: closing phase, OP: opening phase. 1: length with the mouth closed [27
]. 2: Korioth et al. [28
] for the jaw closing muscles. 3: van Eijden et al. [27
] for the jaw opening muscles. 4: Nelson [29
] for the jaw closing muscles. 5: proportional to the values adopted by Hannam et al. [12
] for the jaw opening muscles.