Characterisation of Titanium Dental Implants. II: Local Biomechanical Model~!2009-09-02~!2009-11-20~!2010-04-28~!

Abstract

A theoretical model for estimation of the bone-to-implant interfacial shear strength induced by implant surface roughness has been developed. Two different assumptions regarding the constitutive behaviour of the interfacial bone were made. 1) The bone exhibits an ideally plastic deformation -the plastic mode.2) The bone exhibits a linearly elastic deformation -the elastic mode. In the plastic mode it was found that the estimated interfacial shear strength was directly proportional to the 2D surface roughness parameter mean slope. For the elastic mode a new 2D surface roughness parameter was defined. With this parameter a direct proportionality between parameter value and estimated interfacial shear strength was also obtained in the elastic mode. The model was extended into 3D mode. The model was used to evaluate topographies of implant surfaces. The calculated results showed a similar trend to interfacial shear strength results reported in vivo.

Electronic Properties ofTiO2Nanoparticles Films and the Effect on Apatite-Forming Ability

“…There is only a slight difference between the S a values for the TS + 8 nm and TS + 22 nm surfaces, but the lower value obtained for the smaller particles indicates that the curvature of the particles are reflected in the surface roughness. The root mean square of the slope ( S dq ) has been shown to correlate with the interface shear strength and is thus an important parameter to investigate for dental implant applications [28, 29]. From a biomechanical point of view, a large S dq value is desired giving the TS + P25 surface an advantage.…”

Electronic properties of anodized TiO2 electrodes and the effect on in vitro response

“…By using multiple scan sizes and by applying a Gaussian filter of different sizes in the MeX® software, information about topographical features ranging from 10 µm to 150 nm are received, for details see Refs. and .…”

Global biomechanical model for dental implants

“…The results of the Global biomechanical model (referred to as the Global model) are discussed in correlation to results obtained for the Local model presented in Hansson et al (2010). In a forthcoming paper, the model will be transposed to real surfaces and the correlation between interfacial shear strength and 3D surface roughness parameters under removal torque situations will be established.…”

“…In the following it is assumed that the dominating failure mode is a compressive fracture. For more information see Hansson et al (2010). (7) It is assumed that the bone exhibits an idealized stress-strain curve consisting of a linearly elastic phase followed by a plastic phase where the stress in the plastic phase is constant.…”

“…Doubts have however been expressed about the existence of an unequivocal relationship between the values of a set of surface roughness parameters and expected interfacial shear strength (Hansson, 2000). Recently, Hansson et al (2010) found that, under some assumptions regarding the mechanics of the implant-bone interface, the theoretical interfacial shear strength can be expressed by one single 2D surface roughness parameter -the absolute mean slope. The results of the model, defined for a profile, showed that the interfacial shear strength could also be estimated using the 3D surface roughness parameter S dq (root-mean-square of the surface slope) .…”