Effect of periodontal ligament on stress distribution and displacement of tooth and bone structure using finite element simulation

Abstract

Periodontal ligament (PDL) is a thin layer of collagen fiber that can absorb or reduce the transfer of stress from a tooth to the alveolar bone. To understand the function of PDL, stress distributions and displacement over the tooth and bone structure was simulated using Finite Element Analysis (FEA). To evaluate the credibility of FEA simulation, a simple model was created: a simply rod connection consists of tooth bar, PDL layer, and bone bar. It was performed with theoretical analysis and FEA using simulation to compare and validate the results. It was found that the theoretical analysis and FEA produced similar results. Therefrom, FEA was used to predict in the Orthodontics problem. Due to the complexity of dental geometry, the Computed Tomography was used to create the real tooth into the 3-dimensional model. FEA was then applied to study the role of the PDL layer with tooth and bone when realistic dental forces were applied using simulation models with and without PDL. The results showed that the maximum stress was higher and very small displacement in the model without the PDL layer. Thus, the PDL acts as a sustaining pad that decreases and intersperses the stress in the alveolar bone. Furthermore, the soft pad of the PDL layer allows the tooth to move more easily.