Stress analysis of temporomandibular joint disc during maintained clenching using a viscohyperelastic finite element model.
OBJECTIVE
People with bruxism exert parafunctional grinding and clenching activities. Those habits are suspected to be associated with temporomandibular disorder development. The aim of this study was to analyze the behavior of the temporomandibular joint disc under maintained clenching.


METHODS
For this analysis, a viscohyperelastic finite element model was used. The model included half the mandible, the left disc, and the left temporal bone and used muscular efforts as loading conditions. The viscohyperelastic properties of the disc were based on literature data from asymptomatic human cadaveric disc specimens.


RESULTS
Stresses in the disc decreased slightly (<15%) after 10 seconds of maintained clenching. In contrast, strains increased in nearly all disc regions, with the maximum (33%) in the lateral part of the disc. The greatest creep strain (-0.1) also was found in the lateral part.


CONCLUSIONS
Results suggest that maintained clenching leads to an increase in strains in the entire disc and to greater creep strain in the lateral part. This may be related to disc damage.
Temporary Contract Researcher, University of Bordeaux, I2M, CNRS UMR 5295, Talence, France. Electronic address: mhamad-aoun@hotmail.com.
Mhamad
M
Aoun
Professor with Agregation (professeur agrégé) University of Bordeaux, I2M, CNRS UMR 5295, Talence, France.
Michel
M
Mesnard
Temporary Contract Researcher, University of Bordeaux, I2M, CNRS UMR 5295, Talence, France.
Lucie
L
Monède-Hocquard
Assistant Professor, Department of Mechanical Engineering, University of Aveiro, Aveiro, Portugal.
Antonio
A
Ramos
D000465:Algorithms; D001696:Biomechanical Phenomena; D002012:Bruxism / Q000503:physiopathology; D002102:Cadaver; D003198:Computer Simulation; D055119:Elastic Modulus; D004548:Elasticity; D020342:Finite Element Analysis; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D021621:Imaging, Three-Dimensional / Q000379:methods; D008406:Masseter Muscle / Q000502:physiology; D008410:Masticatory Muscles / Q000502:physiology*; D008953:Models, Anatomic; D008954:Models, Biological; D009119:Muscle Contraction / Q000502:physiology*; D011626:Pterygoid Muscles / Q000502:physiology; D013314:Stress, Mechanical; D013703:Temporal Muscle / Q000502:physiology; D019224:Temporomandibular Joint Disc / Q000033:anatomy & histology / Q000502:physiology*; D013997:Time Factors; D014783:Viscosity