Modeling of the Effect of Friction in the Temporomandibular Joint on Displacement of Its Disc During Prolonged Clenching

Tanaka, Eiji; Hirose, Miho; Koolstra, Jan Harm; van Eijden, Theo M.G.J.; Iwabuchi, Yasunori; Fujita, Reiji; Tanaka, Masao; Tanne, Kazuo

doi:10.1016/j.joms.2007.06.640

« Previous Next »Journal of Oral and Maxillofacial Surgery
Volume 66, Issue 3 , Pages 462-468, March 2008

Modeling of the Effect of Friction in the Temporomandibular Joint on Displacement of Its Disc During Prolonged Clenching

Eiji Tanaka, DDS, PhD
- Associate Professor, Department of Orthodontics and Craniofacial Developmental Biology, Hiroshima University Graduate School of Biomedical Sciences, Hiroshima, Japan.
- Address correspondence and reprint requests to Dr Tanaka: Department of Orthodontics and Craniofacial Developmental Biology, Hiroshima University Graduate School of Biomedical Sciences, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8553, Japan
Miho Hirose, DDS, PhD
- Graduate Student, Department of Orthodontics and Craniofacial Developmental Biology, Hiroshima University Graduate School of Biomedical Sciences, Hiroshima, Japan.
Jan Harm Koolstra, PhD
- Associate Professor, Department of Functional Anatomy, Academic Centre for Dentistry Amsterdam, Amsterdam, The Netherlands.
Theo M.G.J. van Eijden, MD, PhD
- Professor and Chair, Department of Functional Anatomy, Academic Centre for Dentistry Amsterdam, Amsterdam, The Netherlands.
Yasunori Iwabuchi, DDS
- Graduate Student, Department of Orthodontics and Craniofacial Developmental Biology, Hiroshima University Graduate School of Biomedical Sciences, Hiroshima, Japan.
Reiji Fujita, MS
- Graduate Student, Department of Systems and Human Science, Osaka University School of Engineering Science, Osaka, Japan.
Masao Tanaka, PhD
- Professor and Division Chair, Division of Mechanical Science, Department of Systems and Human Science, Osaka University School of Engineering Science, Osaka, Japan.
Kazuo Tanne, DDS, PhD
- Professor and Chair, Department of Orthodontics and Craniofacial Developmental Biology, Hiroshima University Graduate School of Biomedical Sciences, Hiroshima, Japan.

Purpose

The effect of the frictional coefficient in the temporomandibular joint on the disc during prolonged clenching was examined.

Materials and Methods

For this purpose, a finite element model of the temporomandibular joint based on magnetic resonance images from a volunteer subject was used. Muscle forces applied for clenching were used as a loading condition for stress analysis during 10 minutes. With respect to the frictional coefficient between articular surfaces, 3 different values ranging from μ = 0.001 to μ = 0.1 were established.

Results

At the onset of clenching, large stresses were found in the central and lateral part of the intermediate zone in the disc, and its stress distribution was not markedly changed during 10 minutes of clenching. In the retrodiscal tissue, stress relaxation occurred during the first 2 minutes of clenching. When the frictional coefficient between articular surfaces increased, the anterior, lateral, and central points in the disc moved further forward. At the end of 10 minutes of clenching, the disc showed a more anterior position as the frictional coefficient increased.

Conclusion

This result indicates that increase of the frictional coefficient between the articular surfaces may be a major cause for the onset of the disc displacement.