S. Das, University of Michigan, Ann Arbor, MI
This talk discusses ongoing research in my laboratory on advanced design and rapid prototyping (RP) techniques addressing the construction of multifunctional devices. The first part of this presentation focuses on one such class of devices, namely bone tissue engineering scaffolds. The emerging field of tissue engineering poses many challenges, particularly in the repair and reconstruction of complex joints such as the temporo-mandibular joint (TMJ). To reconstruct such joints, novel design and fabrication methods are needed to build scaffolds with anatomic shapes incorporating multiple, spatially varying, biomaterial compositions and porous architectures that will enable the simultaneous regeneration of multiple tissues while temporarily providing structure and functionality. One aim of our ongoing research is to develop techniques for fabricating such scaffolds by combining RP and computational design methods. Using such methods, scaffolds with periodic and biomimetic architectures were fabricated by selective laser sintering of polycaprolactone, a biocompatible, biosorbable polymer with applications in implantable long-term drug delivery devices, as well as bone and cartilage repair. Results of scaffold design, fabrication, in vitro bio-compatibility, mechanical testing and implantation studies will be presented. The second part of this talk will describe the development of a new direct write RP technique for the layered fabrication of meso- and macroscale, compositionally heterogeneous devices. This technique is based on patterned deposition of micro- to nanoscale granular materials through miniature nozzles with a target minimum in-plane feature resolution of 100ìm. While substantial theoretical and experimental work has been conducted on large scale hoppers, little or no work exists on the flow of granular materials in miniature hoppers. I will present existing background, the design of our system and the results of experiments on gravity and vibration assisted deposition of spherical sub-125ìm particles. Proof-of-concept demonstrations on patterned deposition for a variety of applications will be presented.
Summary: This talk discusses ongoing research in my laboratory on advanced design and rapid prototyping (RP) techniques addressing the construction of multifunctional devices. The first part of this presentation focuses on one such class of devices, namely bone tissue engineering scaffolds. The emerging field of tissue engineering poses many challenges, particularly in the repair and reconstruction of complex joints such as the temporo-mandibular joint (TMJ). To reconstruct such joints, novel design and fabrication methods are needed to build scaffolds with anatomic shapes incorporating multiple, spatially varying, biomaterial compositions and porous architectures that will enable the simultaneous regeneration of multiple tissues while temporarily providing structure and functionality. One aim of our ongoing research is to develop techniques for fabricating such scaffolds by combining RP and computational design methods. Using such methods, scaffolds with periodic and biomimetic architectures were fabricated by selective laser sintering of polycaprolactone, a biocompatible, biosorbable polymer with applications in implantable long-term drug delivery devices, as well as bone and cartilage repair. Results of scaffold design, fabrication, in vitro bio-compatibility, mechanical testing and implantation studies will be presented.
The second part of this talk will describe the development of a new direct write RP technique for the layered fabrication of meso- and macroscale, compositionally heterogeneous devices. This technique is based on patterned deposition of micro- to nanoscale granular materials through miniature nozzles with a target minimum in-plane feature resolution of 100ìm. While substantial theoretical and experimental work has been conducted on large scale hoppers, little or no work exists on the flow of granular materials in miniature hoppers. I will present existing background, the design of our system and the results of experiments on gravity and vibration assisted deposition of spherical sub-125ìm particles. Proof-of-concept demonstrations on patterned deposition for a variety of applications will be presented. This talk will conclude with a discussion of scientific and technical challenges, potential applications of and devices envisaged by this technique.
