The skin is the biggest organ in the human body and makes up the majority of an adult’s weight, 20 pounds on average. Our skin has three layers: the epidermis, dermis, and hypodermis. The outermost layer of our bodies, the epidermis serves as a form of armor to shield our bodies from skin injury. The dermis is located underneath the epidermis.
It consists of a thick bottom layer termed the reticular dermis and a thin top layer known as the papillary dermis. Because there is no distinct boundary between these two layers, they overlap and intersect. The hypodermis is located at the bottom, last. This layer is made up of fatty adipose tissue and dense connective tissue. Most attempts to develop a functional skin equivalent fall short of adequately capturing the tiny changes and gradients between each layer due to the complicated tripartite structure of human skin. Serious effects might result from skin damage, such as burns or uncommon infections.
The skin feature
There are many sizes and forms of wounds. Some of them are minor, heal fast, and pose minimal issues. Others recover gradually more slowly. Chronic wounds, which are deep wounds that heal normally but frequently reopen, infect others, and eventually leave scarring, are of special concern. Additionally, persistent wounds are challenging to treat with the methods that are now accessible, which results in significant health issues. Instead of concealing a scar or imperfection with cosmetics or undergoing cosmetic surgery, picture being able to plug a cartridge into an inkjet printer and have printed skin.
Think about how painful skin grafts would be eliminated if doctors could print real skin for burn patients. Researchers want to be able to 3D print skin to minimize permanent damage and facilitate a quicker, less painful recovery. Although 3D bio-printing technology is still quite young, it is already being used in practical settings. Even though it simply had the title “light patch,” one of the first publications regarding the uses of 3D printing live skin was published in 2019. The Hebrew University professor who is also a serial entrepreneur and innovator is working on this technology in Rehovot, Israel.
The first who developed a 3d printer
S. Oded The University of Birmingham, and the University of Huddersfield have created a novel method of treating chronic wounds using tissue engineering. The NOVOPLASM partnership claimed to have developed cold plasma technology “first in the world” for the treatment of infected burns and the healing of skin graft wounds. The collaboration that promotes the development of cold plasma therapy includes the regenerative medicine company CTI BIOTECH, the Biomedical Research Institute of the French Armed Forces, the Ecole Polytechnique, and the Institut Pasteur.
As the first company in the world to 3D bio print fully immunized human skin or CTISkin, CTI BIOTECH is giving the consortium access to hundreds of models so they may test its cold plasma technology. The skin may be readily created utilizing a range of biomaterials and cells using 3D bioprinting in less time and at a lower cost. It is applied to produce healthy tissue that can carry out the necessary tasks. The distinction between 3D printing and 3D bioprinting is discussed in this article. We are beginning to explore methods for 3D printing human skin from actual living cells thanks to recent developments in contemporary 3D printing technology.
This is effective for both repairing and producing human skin that functions just like natural skin. Skin tissue engineering (STE) offers a novel method for addressing skin flaws in comparison to standard procedures. The tissue skin types Integra, Dermagraf, and PELNAC are only a few examples. Cells, bioactive components, and biomaterials make up the majority of TES. It may completely cover full-thickness skin wounds, encouraging the vascularization of skin replacements, and speeding wound healing with reduced scarring. However, TES still has a lot of drawbacks, including unpigmented skin, a lack of dermal elasticity, persistent postoperative scarring, the loss of skin appendages, and the need to repair damaged nerves, all of which have a significant impact on the quality of diabetic patients of life following skin wound healing.
Therefore, in the fields of tissue engineering (TE) and regenerative medicine, the regeneration of the skin and appendages is a pressing issue that has to be resolved. We can now print functioning skin and appendages thanks to the ongoing development of three-dimensional (3D) printing technology and its accuracy and high resolution. Therefore, it is anticipated that these TES restrictions will be lifted. A patch is a good short-term fix, but 3D-printed skin for grafts and aesthetic surgery is created by manipulating different cells that make up the dermis and epidermis. Similar to stem cells, these cells will behave by the instructions given to them, with the ultimate goal of creating artificial skin that can interact with the vascular system as naturally as possible and function like human skin.
The only type of bonding agent the researchers could originally print was one that was friendly to human skin. This served as an infection barrier and aided in the healing process, but it did not directly encourage cell reorganization like genuine skin. Making 3D-printed skin with functional blood vessels that behave like human skin and act like a conventional graft was the solution to this problem. To limit the possibility of immune system rejection, they will need to consider biocompatibility. Despite the spectacular growth factors of 3D printing since its introduction in the late 1980s, 3D bioprinting is still not in widespread use. This is because creating even the most fundamental components of actual bio-printed organs is now expensive and time-consuming, and because stimulating every component of a human organ or tissue is challenging.
Types of 3d printers
Although there have been numerous advances in research, 3D-printed leather and textiles are not yet practical for everyday usage outside of research institutes and departments. Trials are currently underway. Use of Droplets for Bioprinting (DBB). Inkjet bio-printing (IJB), electrohydrodynamic (EHD) inkjet bio-printing and laser bio-printing are the three primary applications of DBB technology (LAB). Continuous inkjet printing (CIJ) and printing on demand are two categories of IJB (DOD). To continually disseminate ink droplets with conductivity, CIJ printing depends on the intrinsic flow of liquids. Contrarily, DOD printing produces bio-zirconium droplets across the substrate as needed. Drops are produced by CIJ-based bioprinters substantially more quickly than by DoD systems. Due to its great accuracy and little biological waste, DOD is better for material deposition and structuring than CIJ.
To build droplets that can precisely and flexibly deposit different biological elements to create a spatially heterogeneous tissue structure, the Department of Defense usually employs piezoelectric, thermal, or electrostatic forces. For in-situ biological printing, its non-contact printing approach is more appropriate. The skin grafts in the experimental group enhanced wound healing and decreased the skin contracture phenomena in comparison to the control group without any biological dressing. However, the Department of Defense has some limitations. First, its jet diaphragm is extremely small and is easily blocked by biological materials. Only low-viscosity hydrogel or other low-concentration biological agents can be applied to DOD. Second, TES produced by the DoD seal generally lacks a porous structure that does not promote tissue perfusion and metabolism and limits their clinical applications. EHD bio-inkjet printing uses an electric field to draw bio-ink droplets through a hole, causing the bio-ink droplets to be ejected. Thus, the strength of the electric field, the consumption of circulation, and the characteristics of the bio-ink can determine printing methods and cell viability. EHD inkjet bio-printing is suitable for bio-printing highly concentrated bio-zirconium.
EBB technology offers highly regulated printing through the automated machine and fluid distribution systems. Under computer control, pneumatic, piston, or screw drives are used to move the bionic components through the micronozzle as continuous filaments. After printing, a whole object is created layer by layer. The ideal hydrogels for air-based extrusion bioprinting are those having shear thinning properties because they can keep the filaments in good condition after extrusion. High-viscosity bio-ink printing is made possible by the screw design, which results in the creation of more sturdy 3D bio-printed fabric. The most recent extrusion bioprinters include several printheads, which enable the simultaneous deposition of various bio-inks with little risk of cross-contamination. Additionally, they provide the 3d printed skin structure with better control over the cells’ porosity, form, and distribution.
The LAB system is made up of four components: a pulsed laser source, a laser focusing device, a metal tape layer that absorbs the laser energy, and a receiving substrate. Laser light is produced via LAB technology using a pulsed laser source. The silicate glass’s back has a metal coating heated by the laser light, which causes the bio-ink to be deposited to swiftly evaporate and spray liquid droplets onto the substrate.
LAB mainly uses nanosecond ultraviolet or near ultraviolet wavelength laser as its energy source, and its print resolution can reach the picogram level. Michael et al. created a full-thickness skin graft replacement using LAB technology, which was a major victory in the LAB field. Koch et al. use laser direct transfer (LIFT) laser printing to print cells derived from skin cell lines and human mesenchymal stem cells. All cell types retain their ability to proliferate after LIFT, and skin cells and hMSC show ~98% and ~90% cell survival, respectively. LAB equipment has no nozzle, non-contact printing, and can print cells with high activity and high resolution. However, LAB still lacks a suitable fast gel mechanism, which limits the implementation of high throughput printing.
Utilizing photopolymers to produce a photopolymerization under carefully calibrated light, then curing and shaping it, is a form of bioprinting technology called SLA. SLA offers several benefits over conventional bioprinting techniques, including great precision and speed. SLA is frequently used in the biological sector to print regulated geometries, such as very accurate fabric scaffolds with porous pores. Without using shear force on the cells, SLA may produce increased cell survival and quickly bio-print patterns with high resolution.
The most effective way for creating active 3D cell structures in vitro is 3D bioprinting technology, which has the benefits of multicellular spatial directed manipulation and controlled deposition of varied cell densities. Diverse 3D bio-printing methods have different printing procedures, in which the printing equipment, bio-inker viscosity, cell concentration and viability, temperature, and gelation time of biomaterials are critical elements determining 3D bioprinting results.
About the cost of printed skin
The main issue is cost. Depending on the materials used, 3D printing can be an expensive undertaking. Like any medical technology, 3D-printed skin must be of high quality to be functional and safe. And so no expense can be spared. 3D-printed leather has a long way to go before it becomes a valuable asset in everyday life. We might soon be able to 3D print and clone functional human skin thanks to the successful use of 3D-printed hair follicles in so-called “hair cloning.” The advent of 3D-printed skin may also be excellent news for gender reassignment and aesthetic procedures that frequently employ skin from other sections of the patient’s body to make up for body reconstruction.
Can you 3D print skin?
Yes, of course. Nowadays, using the 3d printer means that people can develop human tissue or skin grafts, blood vessels, and human hair, the largest organ.
Can 3D printers print human tissue?
A life-size human hand may be printed using a novel 3D printing technique in 19 minutes as opposed to 6 hours with traditional 3D printing. According to experts, it’s a step in the direction of 3D-printed human organs and tissue.
Is medical 3D printing expensive?
Commercial 3D bio-printing is costly, with top-of-the-line equipment costing substantially more than even the most expensive polymer 3D printers, such as the Poietis NGB-R
What body parts can be 3D printed?
Fortunately, three-dimensional (3D) printed organs are now a possibility because of the development of technology. The printing of living tissues and organs, such as blood vessels, skin, bones, cartilage, kidney, hearts, and livers, is currently possible thanks to 3D bioprinting technology. The unique benefits of 3D bioprinting technology for organ production have greatly raised the bar for conventional medicine.
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