A Pressure Dependent Bone Remodeling Model for Application in Orthodontics

INTRODUCTION The goal of this work is to provide a constitutive model able to represent bone remodeling, accounting for the pressure dependency observed macroscopically on alveolar bone remodeling during tooth movement in orthodontic treatments. For most types of bones, remodeling processes take place in order to adjust the amount of tissue and its topology according to long term loading conditions, following what is called ``Wolff's law'' of bone adaptation [1]. Bone resorption/apposition occurs when disuse/overuse is observed. The bone therefore adapts its density in such a way as to achieve an homeostatic state of stresses. Besides the density change, remodeling also occurs to modify the bone topology, mainly in cancellous bone for which the trabeculae tend to align along the principal stresses directions. However, alveolar bone remodeling seems on a macroscopic scale to depend mainly on the pressure state [2]. One can observe apposition on the tension side of a tooth when loaded with an abnormal mechanical environment, such as the one obtained with orthodontic appliances, as well as resorption on the compression side.