A visco-hyperelastic constitutive model of human periodontal ligament and the verification with finite element method

Abstract

The scientific basis of orthodontics is physics and Newtonian mechanics applied to the tooth-periodontal ligament-bone biologic system. The mechanical response of the periodontal ligament (PDL) to forces has a significant impact on bone remodelling and tooth movement. At the early stages, orthodontists mainly evaluated the PDL mechanical properties by in vitro experiments, which guided the use of forces in the orthodontic process. With the development of computers, finite element (FE) methods were increasingly used in the study of orthodontics. The phenomena and results of PDL mechanical tests are abstracted into constitutive equations. The identified constitutive equations are then implemented in finite element software. The finite element method could be used to simulate in vitro and in vivo experiments and predict the response of PDL under various complex working conditions. A visco-hyperelastic constitutive model is proposed and implemented in finite element technique based on prior static mechanical experiments of human PDL. Some complex experimental conditions are simulated to discuss the properties of the constitutive model.