TITLE:
Application of modified superposition model to viscoelastic behavior of periodontal ligament
AUTHORS:
J. Hazrati, F. Ghalichi, B. Mirzakouchaki
KEYWORDS:
periodontal ligament, viscoelasticity, modified superposition method, stress relaxation
JOURNAL NAME:
Journal of Biomedical Science and Engineering,
Vol.1 No.3,
October
16,
2008
ABSTRACT: The periodontal ligament (PDL) is a soft bio-logical tissue which shows a strongly nonlinear and time dependent mechanical behavior. Re-cent experiments on rabbit PDL revealed that the rate of stress relaxation is strain dependent. This nonlinear behavior of PDL cannot be de-scribed well by the separable quasi linear vis-coelasticity theory which is usually used in tis-sue biomechanics. Therefore, PDL requires a more general description which considers this nonlinearity and time dependency. The purpose of this study was to model strain dependent stress relaxation behavior of PDL using modi-fied superposition method. It is shown herein that modified superposition method describes viscoelastic nonlinearties well and shows a good compatibility with available experimental PDL data. Hence, the modified superposition model is suggested to describe periodontal ligament data, because it can suitably demon-strate both elastic nonlinearity and strain-dependent stress relaxation behavior of PDL.