Dynamic shear properties of the porcine molar periodontal ligament

Tanaka, Eiji; Inubushi, Toshihiro; Takahashi, Koji; Shirakura, Maya; Sano, Ryota; Dalla-Bona, Diego A.; Nakajima, Akira; van Eijden, Theo M.G.J.; Tanne, Kazuo

doi:10.1016/j.jbiomech.2006.06.022

« Previous Next »Journal of Biomechanics
Volume 40, Issue 7 , Pages 1477-1483, 2007

Dynamic shear properties of the porcine molar periodontal ligament

Eiji 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
- Corresponding author. Tel.: +81822575686; fax: +81822575687.
Toshihiro Inubushi
- Department of Orthodontics and Craniofacial Developmental Biology, Hiroshima University Graduate School of Biomedical Sciences, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8553, Japan
Koji Takahashi
- Department of Orthodontics and Craniofacial Developmental Biology, Hiroshima University Graduate School of Biomedical Sciences, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8553, Japan
Maya Shirakura
- Department of Orthodontics and Craniofacial Developmental Biology, Hiroshima University Graduate School of Biomedical Sciences, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8553, Japan
Ryota Sano
- Department of Orthodontics and Craniofacial Developmental Biology, Hiroshima University Graduate School of Biomedical Sciences, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8553, Japan
Diego A. Dalla-Bona
- Department of Orthodontics and Craniofacial Developmental Biology, Hiroshima University Graduate School of Biomedical Sciences, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8553, Japan
Akira Nakajima
- Department of Orthodontics, Nihon University School of Dentistry, Tokyo, Japan
Theo M.G.J. van Eijden
- Department of Functional Anatomy, Academic Center for Dentistry Amsterdam (ACTA), Amsterdam, The Netherlands
Kazuo Tanne
- Department of Orthodontics and Craniofacial Developmental Biology, Hiroshima University Graduate School of Biomedical Sciences, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8553, Japan

Accepted 26 June 2006. published online 01 September 2006.

Abstract

The role of the periodontal ligament (PDL) is to support the tooth during function and resist external forces applied to it. The dominant vertical component of these forces is associated with shear in the PDL. Little information, however, is available on the dynamic behavior of the PDL in shear. Therefore, the present study was designed to determine the dynamic shear properties of the PDL in the porcine molar (). From dissected mandibles transverse sections of the mesial root of the first molar were obtained at the apical and coronal levels and used for dynamic shear tests. Shear strain (0.5%, 1.0%, and 1.5%) was applied in superoinferior direction parallel to the root axis with a wide range of frequencies (0.01–100Hz). The dynamic complex and storage moduli increased significantly with the loading frequency, the dynamic loss modulus showed only a small increase. The dynamic elasticity was significantly larger in the coronal region than in the apical region although the dynamic viscosity was similar in both regions. The present results suggest that non-linearities, compression/shear coupling, and intrinsic viscoelasticity affect the shear material behavior of the PDL, which might have important implications for load transmission from tooth to bone and vice versa.