Biomechanics of the Temporomandibular Joint
DISCOVERY!
Martin A. Taubman, Editor
E. Tanaka1* and J.H. Koolstra2
1Department
of Orthodontics and Dentofacial Orthopedics, The University of Tokushima Graduate School of Oral Sciences, 3-18-15 Kuramoto-cho, Tokushima 770-8504, Japan; and 2Department of Functional Anatomy, ACTA, Amsterdam, The Netherlands; *corresponding author, etanaka@ dent.tokushima-u.ac.jp J Dent Res 87(11):989-991, 2008
Biomechanics of the Temporomandibular Joint
INTRODUCTION his article is in honor of the late professor Theo van Eijden, who passed away on February 28, 2007. During his career as chairman of the Department of Functional Anatomy at the Academic Centre for Dentistry Amsterdam, he was very productive in his contributions to our understanding of the biomechanics of the human masticatory system. First and foremost, however, he was a great inspiration for his fellow researchers, from both his own institute and beyond. Temporomandibular joint (TMJ) disorders were recognized in the early dental (Gysi, 1921) and medical (Costen, 1997 [reprinted from 1934]) literature as an individual source of facial pain. The function of this joint, however, was not regarded as important. For instance, initially, the TMJ was not considered to be a load-bearing joint. Also, the movement possibilities of the joint were poorly understood, as illustrated by a persistent belief in the concept of a more or less ‘predetermined’ instantaneous center of rotation (Grant, 1973). One of the major complicating factors in comprehension of the function of the TMJ is the presence of its disc, which, in certain circumstances, appears to be able to dislocate temporarily or permanently. In the latter case, this can lead to degeneration and may cause severe pain and/or masticatory dysfunction. The causes for such a disc displacement as well as its consequences are not yet understood. Treatment remedies for TMJ dysfunction include medication (for example, NSAIDs), conservative approaches (for example,
Martin A. Taubman, Editor
E. Tanaka1* and J.H. Koolstra2
1Department
of Orthodontics and Dentofacial Orthopedics, The University of Tokushima Graduate School of Oral Sciences, 3-18-15 Kuramoto-cho, Tokushima 770-8504, Japan; and 2Department of Functional Anatomy, ACTA, Amsterdam, The Netherlands; *corresponding author, etanaka@ dent.tokushima-u.ac.jp J Dent Res 87(11):989-991, 2008
Biomechanics of the Temporomandibular Joint
INTRODUCTION his article is in honor of the late professor Theo van Eijden, who passed away on February 28, 2007. During his career as chairman of the Department of Functional Anatomy at the Academic Centre for Dentistry Amsterdam, he was very productive in his contributions to our understanding of the biomechanics of the human masticatory system. First and foremost, however, he was a great inspiration for his fellow researchers, from both his own institute and beyond. Temporomandibular joint (TMJ) disorders were recognized in the early dental (Gysi, 1921) and medical (Costen, 1997 [reprinted from 1934]) literature as an individual source of facial pain. The function of this joint, however, was not regarded as important. For instance, initially, the TMJ was not considered to be a load-bearing joint. Also, the movement possibilities of the joint were poorly understood, as illustrated by a persistent belief in the concept of a more or less ‘predetermined’ instantaneous center of rotation (Grant, 1973). One of the major complicating factors in comprehension of the function of the TMJ is the presence of its disc, which, in certain circumstances, appears to be able to dislocate temporarily or permanently. In the latter case, this can lead to degeneration and may cause severe pain and/or masticatory dysfunction. The causes for such a disc displacement as well as its consequences are not yet understood. Treatment remedies for TMJ dysfunction include medication (for example, NSAIDs), conservative approaches (for example,
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