Four-axis FDM printing – Novel Methodology for Scaffold Fabrication

Abstract

In this paper authors presented novel method for FDM printing of Biodegradable Vascular Stents (BVS) from Poly Lactic Acid (PLA) polymer. Method implies rearranging standard FDM printer with Cartesian coordinate system (X, Y, Z) to enable rotational printing around one rotating axis. This way, buy including rotating axis, a four-axis printing system is created, which allows printing directly on rotating drum without supporting structures. In this example, Y-axis translatory movement is translated into drum rotary movement, avoiding the need for printer reprogramming. Opposing to the standard FDM printing, CAD files for rotary printing are needed to be prepared in unfolded form. In this way, specimens surface integrity and manufacturing efficiency are both improved. Practical implementation of this method creates novel options for printing tubular, radially loaded structures where mechanical properties are as important as surface quality. For example, shape-memory vascular stents can be produced in this way, incorporating four-dimension – four-axis printing of such structures. Combining development of new 3D printing materials and this printing method, opens wide possibilities for developing biocompatible, programmable support structures, which can be inserted into human vessels and then expanded by external stimulus (E.g., temperature), enhancing blood flow with minimal invasive effects for patient – reducing recovery time. In addition, new structure geometrical models can be developed having in mind 4-axis printing possibility.