Finite Element Simulation of Bone Remodelling in Human Mandible Around Osseointegrated Dental Implant

Abstract

Modern dental implant is a biocompatible titanium device surgically placed into a jawbone to support a prosthetic tooth crown in order to replace missing teeth. Implants are superior to conventional prostheses, in both function and long-term predictability. However, placement of an implant changes the normal mechanical environment of jawbone, which causes the bone density to redistribute and adapt to the new environment through a process of remodelling. This study aims to predict the density distribution in human jawbone around osseointegrated dental implant. Based on two popular, yet distinctive theories for bone remodelling, a new remodelling algorithm is proposed. The proposed algorithm is verified by a two-dimensional (2D) plate model. Then, a 2D finite element model of implant and jawbone is studied. The effects of two parameters, viz the reference value of strain energy density (SED) and 'lazy zone' region, on density distribution, are also examined. This study has demonstrated that consideration of the lazy zone, is less important than consideration of the stress and strain (quantified as SED) induced within the bone. Taking into account both 'lazy zone' effect and self-organisational control process, the proposed bone remodelling algorithm has overcome the shortcomings of the two existing theories.