Multiscale design of porous implants with a biomimetic functionally graded cellular material

Endosseous implants are now widely used in clinical practice to restore joint functionality or to replace missing teeth.

Despite theirincreasing success, implant long-term stability remains a concern and it is difficult to predict the surgical outcome so far.

Amajor cause of failure comes from bone resorption secondary to stress shielding, which arises from the mismatch of themechanical properties between the implant and the surrounding bone tissue.

To overcome this problem, MIDPOINT proposes todesign porous implants that will have a biomimetic cancellous bone microstructure with a nonhomogeneous distribution of itsmaterial properties.

The optimal design will produce implants with mechanical and microstructural properties similar to that ofthe bone, which will result in an improvement of the effectiveness of osseointegration phenomena.A work methodology that combines multiscale computational modelling and experimental work for the formulation,construction, verification and validation of computational models is proposed.

This methodology will comprise i) the design ofnew biomimetic microstructures that replicate the geometrical properties of the natural trabecular bone using a generativedesign approach, the Voronoi tessellation approach; ii) the development of an iterative computational method to predict thefatigue life of the artificial microstructures directly at the macroscale employing damage accumulation models coupled withartificial neural networks; and iii) the construction of multiscale models of bone-implant systems to optimize the implantmicrostructure locally in order to achieve a desirable mechanical response and functional environment for bone ingrowthand, therefore, minimize bone resorption.

These techniques will be employed to design implants and scaffolds that, togetherwith medical imaging techniques, can be personalized to the needs of each patient and directly printed at the medicalinstitution using additive manufacturing techniques.