Trabecular bone strains around a dental implant and associated micromotions—A micro-CT-based three-dimensional finite element study

Abstract

a b s t r a c tThe first objective of this computational study was to assess the strain magnitude and distribution within the three-dimensional (3D) trabecular bone structure around an osseointegrated dental implant loaded axially. The second objective was to investigate the relative micromotions between the implant and the surrounding bone. The work hypothesis adopted was that these virtual measurements would be a useful indicator of bone adaptation (resorption, homeostasis, formation).In order to reach these objectives, a mCT-based finite element model of an oral implant implanted into a Berkshire pig mandible was developed along with a robust software methodology. The finite element mesh of the 3D trabecular bone architecture was generated from the segmentation of mCT scans. The implant was meshed independently from its CAD file obtained from the manufacturer. The meshes of the implant and the bone sample were registered together in an integrated software environment. A series of non-linear contact finite element (FE) analyses considering an axial load applied to the top of the implant in combination with three sets of mechanical properties for the trabecular bone tissue was devised. Complex strain distribution patterns are reported and discussed. It was found that considering the Young's modulus of the trabecular bone tissue to be 5, 10 and 15 GPa resulted in maximum peri-implant bone microstrains of about 3000, 2100 and 1400. These results indicate that, for the three sets of mechanical properties considered, the magnitude of maximum strain lies within an homeostatic range known to be sufficient to maintain/form bone. The corresponding micro-motions of the implant with respect to the bone microstructure were shown to be sufficiently low to prevent fibrous tissue formation and to favour long-term osseointegration.

Interaction of bone–dental implant with new ultra low modulus alloy using a numerical approach

“…The threads allow stress in the bone to be staged and they thus limit the maximum stress in the lower part of the cortical bone-implant 15 interface. The reduction of the stress shielding requires both an adapted shape and a low modulus material.…”

“…As the Young's modulus of the cortical and the trabecular bones is difficult to determine experimentally, adapted values for cortical and trabecular bones have been considered (15 GPa and 1 GPa, respectively) [46].…”

“…A considerable number of experimental and numerical studies have been carried out to understand the mechanism of the load transfer from the implants to the bones [9][10][11][12][13][14][15][16]. A geometric influence has been demonstrated.…”

“…Load transfer between an implant and the surrounding bone has recently been intensively studied using Finite Element Modelling [8]. Several parameters related to the implant have to be considered, such as geometry, loading, the interaction between the implant and the cortical bone, and material properties.A considerable number of experimental and numerical studies have been carried out to understand the mechanism of the load transfer from the implants to the bones [9][10][11][12][13][14][15][16]. A geometric influence has been demonstrated.…”

Critical Aspects for Mechanical Simulation in Dental Implantology

“…The analysis criteria widely used in implant prosthodontics are: (1) von Mises stress (σ vM ) (Yokoyama, Wakabayashi et al 2005;Assuncao, Tabata et al 2008;Huang, Hsu et al 2008;Lim, Chew et al 2008;Rubo and Souza 2008;Schrotenboer et al 2008;Assuncao et al 2009;Assuncao et al 2009;Chaichanasiri, Nanakorn et al 2009;Ding et al 2009;Fazel, Aalai et al 2009;Gomes et al 2009;Kong et al 2009;Li, Kong et al 2009;Qian et al 2009;Abreu et al 2010;Ao et al 2010;Caglar et al 2010;Eraslan and Inan 2010;Eser et al 2010;Faegh and Muftu 2010;Gomes et al 2010;Miyamoto et al 2010;Okumura, Stegaroiu et al 2010;Sagat, Yalcin et al 2010;Takahashi et al 2010;Teixeira et al 2010;Winter et al 2010;Bevilacqua et al 2011;Burak Ozcelik, Ersoy et al 2011;de Almeida, Rocha et al 2011;Okumura et al 2011), (2) maximum and minimum principal elastic strain (Є max and Є min ) (Saab et al 2007;Qian, Todo et al 2009;Chou, Muftu et al 2010;Danza, Quaranta et al 2010;Eser, Tonuk et al 2010;Limbert et al 2010;Okumura, Stegaroiu et al 2010;de Almeida, Rocha et al 2011) and (3) maximum and minimum principal ...…”