Biomedical Engineering Reference
In-Depth Information
Biomechanical Characterization and Modeling
of Natural and Alloplastic Human
Temporomandibular Joint
Michel Mesnard and Antonio Ramos
Abstract
To improve reduced functions of the temporomandibular joint, total
replacement involves removing the non-functional joint and replacing it with an
artificial one. Recent prostheses may lead to different cases of failure that require
additional surgical procedures. Some solutions are available to improve the artificial
joint survival rate. Materials and geometry play important key roles in enhancing the
long-term life of the joint, but the biomechanics of the human masticatory system
must also be well characterized. Forces applied to the mandible by muscles, articular
joints and teeth need to be determined to assess the strain and stress patterns of the
whole mandible and particularly of the condyle area to control the effects of stress
shielding. While the femur, for example, is a well-documented bone structure, this
is not the case for the mandible bone; there seems to be little investigation in the
literature into the biomechanics of the mandible.
The first part of the study describes the characterization of the muscular actions,
i.e. the forces exerted by the elevator muscles that were considered: deep and
superficial masseters, pterygoid and temporal. In vivo electromyography and MRI
contributed to quantifying force intensities when the mandible was loaded. This
load between the teeth was recorded using a sensor which also adjusted the mouth
aperture. The description of the articular surfaces and the calculations of the
muscular insertion co-ordinates were obtained from four cadaver dissections.
In the second part of the study, the synthetic mandible was digitized with a laser
scanner device to build the finite element model. The solid model of the mandible
was created with a modeling package after digitizing the surfaces. The study proved
that the finite element model of the mandible can reproduce experimental strains
M. Mesnard (
)
Universite de Bordeaux, Institut de Mecanique et d'Ingenierie,
CNRS UMR 5295, Bordeaux, France
e-mail:
michel.mesnard@u-bordeaux1.fr
A. Ramos
Department of Mechanical Engineering, University of Aveiro, Aveiro, Portugal
