A manufacturing approach to functional biomimetic three-dimensional-printed bone implants

Abstract

Orthopedic surgeons frequently face the problem of selecting adequate implants that fulfill certain characteristics of mechanical stability and biological features. Recent three-dimensional printing advancements have made possible the use of biologically compatible materials in regenerative medicine in order to meet the increasing demand of tissue and organs, including bones. Current three-dimensional printing bone technologies can create either strong bone structures (based on primary scaffolds) that are structurally compatible but functionally inert or structures that have osteoconductive properties but are extremely weak. In this context, the present article presents a follow-up study based on previous analysis in which a new technique is used to create high-resistance implants using biocompatible materials as acrylonitrile butadiene styrene to print biomimetic scaffolds directly from computer assisted design data. The main objective is to develop a design methodology to model and create artificial bone tissue, based on the trabecular pattern of the host, to obtain scaffolds within a structural design that mimics the mechanical resistance of the patients’ bone. These scaffolds, obtained from a micro-tomography, would generate stronger structures by enhancing them with osteoblast precursor cells in an osteogenic habitat in order to generate bone tissue in their surface. Mechanical strength of these scaffolds is also analyzed by comparing models with and without trabecular patterns using a standard compression test. The anisotropy of the structures was also considered in this analysis. Results confirm that trabecular pattern and bone matrix formation enhances the mechanical strength of the scaffolds obtaining similar values as of real trabecular tissue. The clinical use of the developed structures would constitute a new generation of three-dimensional-printed functional implants.