3D Printing Human Organs
Organ printing uses three – dimensional computer printing techniques in which a computer 3D model is placed into a 3D printer and lays out successive polymer or latex layers before 3D objects are produced. The material that was used by printer is a biocompatible polymer in the situation of organ printing. The following section discusses 3D Printed Bone Tissue, 3D Printing Skin Tissue, and 3D Printed Ear.
3D Printed Bone Tissue
3D printing technology solutions demonstrated significant benefits in creating porous scaffolds with macro pores designed for formulation in bone tissue engineering. Till now, though only one form of macro pore was reported in 3D-printed, organic ceramic scaffolds. In general, individuals scaffolds with a single type of macro pore possess significantly lower porosity and porous surfaces, limited oxygen and nutrition delivery to surviving cells, and new bone tissue formation in the centre of the scaffolds.
In China the above idea is considered as a subject of research and an alternative model is created. They prepared a hollow-struts-packed (HSP) bio-ceramic scaffolds combining high porosity with impressive mechanical strength with the surface area. The special properties of the hollow strut of biological ceramic boards have enhanced dramatically the attachment and proliferation of cells and further promoted the development of fresh bone tissue in the centre of the scaffolds suggesting that HSP ceramic scaffolds may be used to rebuild large bone defects. Additionally, it can be used to create another HSP ceramic scaffolds which show that tissue engineering, mechanical engineering, catalysis and environmental materials have wide acceptance.
3D Printing Skin Tissue
Patients with skin burns and severe wound injuries often have long-term recovery and extensive and costly treatments. The autologous split thickness skin graft (ASSG) is the most frequently used technique for treating large wounds. A skin tissue is implanted in the wounded region and tends to repair and heal the cut. This procedure is focused on extracting a layer of skin from some section of the patient’s body and re-applying it at the location of damage. The downside of ASSG is that it is constrained by the number of recipient areas, which produces another damage location as well. 3D biomaterial printing will mitigate the ASSG-related issues. Skin cells are grown in a laboratory and mixed for bioprinting with biocompatible polymers.
LASER based Inkjet Bioprinting Skin Tissues
In Germany, laser research institute in Laser Zentrum Hannover (LZH) have documented the usage of a laser-based inkjet printing process for 3D skin printing. Such inks made of serum blood / gelatin and fibroblast fluid, keratinocytes and the biomaterials of collagen. Collagen is the main skin extracellular matrix portion (ECM). The team showed, by proliferating cells in histologic parts, that the laser-based printing system will not damage the cells.
3D Printed Ear by DIW Technique
The tympanic membrane, also referred to as eardrum, has a thin layer of tissue that absorbs sounder noise from ambient air and transfers it on to tiny bones in the tympanic (middle-ear) cavity in an auditory ossicular.
In Harvard University, the tympanic membrane scaffold was designed using the Direct Ink Write (DIW) Process, consisting of materials focused on Poly dimethyl siloxane (PDMS), Polylactic acid (PSL), and Poly caprolactone (PCL). The team has proved that materials with similar properties can be designed and manufactured in comparison with human specimens. Concentration rings for each 3D graft organize high frequency displacement and acoustics, which were highly dependent on the patterns and mechanical characteristics, characterized by digital optoelectronics holography, vibrometry of laser doppler and mechanical dynamic analysis.