Influence of surface coatings on the stress distribution by varying friction contact at implant-bone interface using finite element analysis

The present work aims to evaluate the effect of various surface coatings of titanium dental implants by varying the friction coefficient (mu) at the interface between the dental implant and jawbone using finite element analysis (FEA) methods and to provide a comparative analysis between the various surface coatings and implant designs. An accurate model of the dental implant prosthetics consisting of the hard (cortical) and the soft (cancellous) bone, with the various titanium dental implant designs was modelled using a 3D CAD software, and the FE mesh model was generated using HyperMesh 13.0. Three coatings having different coefficient of friction values were selected: Titanium Nitride (TiN) with a friction coefficient of 0.19, Titanium Oxide (TiO2) with a friction coefficient of 0.30 and Zirconium Nitride (ZrN) with a coefficient of friction of 0.49. The non-linear static stress analysis was conducted under three different loading conditions (vertical, lateral and oblique loading) using a CAE solver. The present study showed that surface coatings with high friction coefficients generated lower stresses in the cancellous bone while generating higher stresses in the cortical bone. However, for dental implants having microthreads in their neck region, surface coatings with a high coefficient of friction generated lower stresses at the interface between the cortical bone and the implant. The FEA results indicate that selecting suitable surface coatings would significantly decrease the stresses developed at the bone-implant interface, and future studies should conduct in vivo trials to validate the FEA results obtained.