title: The influence of the human TMJ eminence inclination on predicted masticatory muscle forces.
abstract: Aim of this paper was to investigate the change in masticatory muscle forces and temporomandibular joint (TMJ) reaction forces simulated by inverse dynamics when thesteepness of the anterior fossa slope was varied. We used the model by de Zee et al. (2007) created in AnyBody™. The model was equipped with 24musculotendon actuators. Mandibular movement was governed by thetrajectory of theincisal point. The TMJ was modelled as a planar constraint canted 5°medially and thecaudal inclination relative to the occlusal plane was varied from 10° to 70°. Our models showed that for the two simulated movements (empty chewing and unilateral clenching) the joint reaction forces were smallest for the eminence inclination of 30° and 40° and highest for 70°. The muscle forces were relatively insensitive to change of the eminence inclination for the angles between 20° and 50°. This did not hold for the pterygoid muscle, for which the muscle forces increased continually with increasing fossa inclination. For empty chewing the muscle force reached smaller values than for clenching. During clenching, the muscle forces changed by up to 200N.
authors.affiliation: Clinic of Masticatory Disorders, Removable Prosthodontics, Geriatric and Special Care Dentistry, University of Zürich, Plattenstrasse 11, 8032 Zürich, Switzerland; Laboratory of Biomechanics, Department of Mechanics, Biomechanics and Mechatronics, Faculty of Mechanical Engineering, Czech Technical University in Prague, Technická 4, 16607 Prague 6, Czech Republic. Electronic address: Michala.Markova@zzm.uzh.ch.
authors.forename: Michala
authors.initials: M
authors.lastname: Marková
authors.affiliation: Clinic of Masticatory Disorders, Removable Prosthodontics, Geriatric and Special Care Dentistry, University of Zürich, Plattenstrasse 11, 8032 Zürich, Switzerland. Electronic address: luigi.gallo@zzm.uzh.ch.
authors.forename: Luigi M
authors.initials: LM
authors.lastname: Gallo
mesh_terms: D000328:Adult; D001732:Bite Force; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008334:Mandible / Q000033:anatomy & histology / Q000502:physiology; D008410:Masticatory Muscles / Q000502:physiology*; D003765:Models, Dental; D011626:Pterygoid Muscles / Q000502:physiology; D013704:Temporomandibular Joint / Q000033:anatomy & histology / Q000502:physiology*; D014057:Tomography, X-Ray Computed
keywords: AnyBody™; Masticatory force; Masticatory muscles; Temporomandibular joint; Theoretical models