Fabrication of customised scaffolds using computer-aided design and rapid prototyping techniques

Purpose - This paper details the derivation of the mathematical formulae of a novel system for designing and fabricating tissue engineering (TE) scaffolds. Design/methodology/approach - This work combines the unique capability of rapid prototyping (RP) techniques with computer-aided design (CAD) and imaging software to design and fabricate customised scaffolds that are not only consistent in microstructure but also readily reproducible. The prototype system, called the computer-aided system for tissue scaffolds (CASTS), has a parametric library of design units which can be assembled into scaffold structures through an in-house algorithm. An additional module, the slicing routine, has also been added to improve the functionality of the system. To validate the system, scaffolds designed were fabricated using a powder-based RP technique called selective laser sintering (SLS). Findings - It is shown that the CASTS can be used to exploit CAD and medical imaging techniques together with RP systems to produce viable scaffolds that can be customised for various applications to suit the needs of individual patients. Research limitations/implications - Further research is being done to examine the internal microstructure of the scaffolds and to determine the mechanical properties, as well as to study the inter-relationship between cell proliferation and the pore shapes of the scaffolds. Originality/value - The crucial role of scaffolds in TE has long been recognised. Successful TE scaffolds should have controllable characteristics such as pore size, porosity, and surface area to volume ratio as well as interconnectivity within the scaffolds. Much work has been carried out to produce such TE scaffolds with varying degrees of success. One major drawback is that the resultant TE scaffolds are not readily reproducible. The potential of CASTS lies in its ability to design and fabricate scaffolds with varying properties through the use of different unit cells and biomaterials to suit different applications.