Silicone artificial skin

Another type of membrane designed as an artificial skin coating for bums also exploits the high permeability of siloxane polymers.18,203 The inner layer of the membrane consists primarily of protein and serves as a template for the regenerative growth of new tissue. The outer layer is a sheet of silicone polymer, which not only provides mechanical support, but also permits outward escape of excess moisture while preventing ingress of harmful bacteria. 

If we consider the reasonable form of the practical artificial skin system, it is most likely that the pressure data read out from organic integrated circuits would be transferred to silicon chips. In this sense, some readers may want to claim that it is not necessary to build a decoder or selector with organic transistors. The denser and the larger-area integrated circuits, however, require the more complicated packaging and fine wiring, which cannot be easily achieved with silicon at reasonable cost. Thus our opinion is that it is very important to realize func-... 

Temporary replacement skins have also been studied by using velour fabrics (usually a nylon or Dacron) backed by a polymeric film (silicone or protein) (36). synthetic polypeptides (37). collagen (38). and dextran hydrogels (39). These replacement materials are only for short term use and could be classed as wound dressings. Although they do prevent gross infection and body fluid loss, they do not duplicate any of the other functions of the skin. A true artificial skin does not yet exist. 

Silicone chemists create structures similar to those of the silicates by adding various reactants to create silicone chains, sheets, and frameworks. Chains are oily liquids used as lubricants and as components of car polish and makeup. Sheets are components of gaskets, space suits, and contact lenses. Frameworks find uses as laminates on circuit boards, in nonstick cookware, and in artificial skin and bone. 

A 10-year effort to design an artificial skin (1) has yielded a bilayer polymeric membrane comprising a top silicone elastomeric layer and a bottom layer consisting of a novel, highly porous cross-linked collagen-glycosaminoglycan (GAG) network. The polymeric bilayer is termed a Stage... 

Silicone is widely used in artificial limbs and in fixing defects of the body, membranes, implanted capsules for slow-release medications, artificial skin and in insulation of implanted electrical devices. 

The design and development of prosthetic devices has been supported in government and nongovernment sectors alike. The Johns Hopkins Applied Physics Laboratory has developed prosthetic arms that are rechargeable and motor-driven for people unable to use prosthetics that depend on muscle activity. Alatheia Prosthetics of Brandon, Mississippi, has developed an artificial skin that closely resembles human skin. At Alatheia, architects use medical-grade silicone to create realistic tissue to ensure every crease, pore, and fingerprint is perfect for each patient. 

Artificial skin A bilayer membrane consisting of an upper layer of silicone and a lower layer of DRT. The template is a cell free, highly porous analog of ECM. 

Silicones, also known as polysiloxanes, constitute a class of polymers that find applications in a wide variety of commercially successful products. In biomedical engineering, silicone rubbers have been used in respirator tubes, dental impression, drug delivery, artificial skin, dialysis, catheters etc. Silicones have also been used in beauty products such as skin cream, facemasks, hair products, deodorants, lipsticks, etc. Silicones... 

Silicones have been used in medical science for a variety of prosthetic applications because of their unique properties such as biocompatibiUty, weather resistance, low chemical reactivity, oxidation resistance and low toxicity. These properties make them suitable for a variety of applications, including maxillofacial reconstruction, breast implants, cochlear implants, artificial corneas and artificial skin. Silicone rubber (SR) implants have long been used for local contour corrections, such as nasal, chin, and cheek augmentation. In addition, arthritic knees and joints are effectively replaced by SR prostheses [1 ]. 

As promising as Yannas s original formulation was, it suffered from one major problem. In a patient who is severely burned, there may not he enough healthy skin tissue available to harvest the epidermis needed to replace the silicone coating on the artificial graft. Yannas s solution to this problem was to develop an artificial epidermis that could he implanted at the same time as the artificial dermis. 

There are two types of maxillofacial implants extraoral and intraoral. The former deals with the use of artificial substitutes for reconstructing defective regions in the maxilla, mandible, and face. Useful polymeric materials for extraoral implants require (1) match of color and texture with those of the patient (2) mechanical and chemical stability (i.e., material should not creep or change color or irritate skin) and (3) ease of fabrication. Copolymers of vinyl chloride and vinyl acetate (with 5 to 20% acetate), polymethyl methacrylate, silicones, and polyurethane rubbers are currently used. Intraoral implants are used for repairing maxilla, mandibular, and facial bone defects. Material requirements for the intraoral... 

Fig. 3 Artificial sebum (Stefaniak and Harvey 2006) uptake capaeity in mesoporous silicon (Lee et al., 2009, Preliminary study of mesoporous silicon capacity to adsorb skin sebum, Intrinsiq Materials Ltd TM0902, unpublished report ). From left to right dry mesoporous silicon (80 % porosity), sebum volume that can be adsorbed prior to wet point, sebum adsorbed powder. Note how the volume of powder has not redueed appreeiably that would signify skeleton eollapse...

The study of skin color components, distribution and texture is very important to disclose the appropriate pigment composition and shade when medical grade silicone have to be used as an artificial replacement to any mutilated facial or body structure [1], Much research was conducted to find color pigments that could simplify and enhance the color matching process of medical grade silicone [2,3],... 

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