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materials using manufacturing techniques on a nanoscale. multi‑drug resistant organisms as well as exhibiting
The nanofibers provide a three‑dimensional structure that antiinflammatory properties. [9,10] Nanoscale fabrication
mimics the native extracellular matrix (ECM) while the techniques have allowed manufacturing silver into
host tissue regeneration replaces the scaffold. Nanofiber nanoparticles, which markedly increases the rate of silver
scaffolds provide several properties that are essential for ion release, and thus increasing its clinical utility. [10,11] A
tissue repair: mechanical integrity, temperature control, nanocrystalline silver dressing was recently evaluated
fluid absorption, and gas exchange. in chronic wounds by Sibbald et al. In a prospective,
[9]
uncontrolled study, a variety of chronic, nonhealing
In rat models, scaffolds made of collagen nanofibers
accelerate acute wound healing by enhancing capillary wounds (foot, pressure, and venous stasis ulcers, and
and fibroblast proliferation. In a study by Choi et al., miscellaneous wounds) were treated with a nanocrystalline
[6]
[6]
recombinant human epidermal growth factor (EGF) was sliver dressing [Figure 1]. Surface bacterial counts were
found on semi‑quantitative swabs to be significantly
immobilized on electrospun biodegradable nanofibers diminished in those wounds treated with nanocrystalline
to treat diabetic ulcers in a rat model. Human primary dressing. Since bacteria contribute to tissue damage
keratinocytes were cultivated on the nanofiber matrix leading to poor wound healing, the decreased bacterial
to investigate the effect of EGF nanofibers on their load from silver nanocrystalline dressing facilitates wound
differentiation. Wound healing effect of the EGF nanofibers healing. In addition, growth factors have been shown to
was confirmed in diabetic animals with dorsal wounds. In play a critical role in the proliferative phase of wound
in vivo wound healing studies, the EGF‑nanofibers group
was superior to control groups (conventional dressing, healing. Growth factors serve to attract the cells necessary
for fibroblast and epithelial cell growth and migration, as
nanofibers alone, or EGF solutions). This study showed well as initiating the formation of new blood vessels into
that EGF‑conjugated nanofibers could potentially be the area of injury. Novel polymerized nanocarriers have
employed as a novel wound healing material by increasing been produced, which can provide for consistent and
proliferation and phenotypic expression of keratinocytes significant dosages of growth factors. The growth factors
in diabetic wounds.
are embedded into the polymerized nanocarriers that
Chitin and chitosan nanofibrils are nanocrystals of allow sustained release of these bioactive molecules. The
natural polysaccharides derived from the exoskeletons nanocarrier drug delivery system has been successful in
of crustaceans. These fibrils have been used in a variety treating wounds in a clinical setting. [10]
of formulations to aid wound healing. Muzzarelli et al.
[7]
showed in murine models that different formulations of The cosmetic and topical skin care industries have also
chitin nanofibrils almost lead to normal physiologic benefited from advances in nanotechnology. For example,
repair of wounds. They subjected various formulations of micronized zinc oxide and titanium dioxide (TiO ) are used
2
dibutyryl chitin (DBC), a modified chitin carrying butyryl in sunscreen manufacturing by functioning as ultraviolet
group at the three and six positions, to a battery of in vitro blockers in these products. Their nanoscale fabrication
and in vivo tests. The DBC’s were then incorporated into increases their transparency on skin and allows increased
a 5‑methylpyrrolidinone chitosan solution and submitted user compliance. In addition, it also increases their
[12]
to freeze‑drying to produce a reinforced wound dressing refractive index, resulting in a “stronger” sunscreen.
material, which was then tested in vivo in full thickness Lipid nanoparticles have been added to various cosmetic
wounds in rats. The rats had full thickness dorsal wounds and dermal products to increase contact with the stratum
bilaterally and treated with the experimental agent on one corneum. Therefore, it allows increased drug penetration
side, and control on the contralateral side. The animals into the skin, improved hydration through their occlusive
were studied at either 7 or 14 days and the skin of each properties, and provide controlled release of active
[13]
surgical wound was excised. The use of 4 mm × 4 mm ingredients. In an open clinical trial, fullerene gel
pieces as wound dressings resulted in significantly less applied to patients with acne vulgaris showed a significant
cutaneous scarring, as measured by collagen I/collagen III reduction cutaneous inflammation and infection,
rations, and as measured clinically. suggesting yet another application of nanotechnology in
skin care. [14]
Chitin nanofibrils/chitosan glycolate can be manufactured
into a spray, gel or impregnated onto a dressing for IMPLANTS AND PROSTHESES
wound care. Using a rat model, Mattioli‑Belmonte
et al. demonstrated that each of these delivery systems In 2012, breast augmentation and implant‑based breast
[8]
has a specific application: use for superficial abrasions, reconstruction after mastectomy were the most common
shallow wounds in aesthetic areas, and slow healing plastic surgery procedures. Breast implants that contain
dermo‑epidermal wounds, respectively. Enhanced tissue nanofiber coatings for the delivery of tumor‑specific
repair and reduced scarring was seen in all the applications. anticancer drugs are currently being evaluated. This
[15]
Although the results from all of these studies are impressive, technology has the potential to revolutionize cancer care,
they have not been examined in human clinical trials.
by facilitating area‑specific chemotherapy to the tumor
Silver has long been heralded for its antimicrobial bed while alleviating some of the undesirable effects of
properties and has demonstrated efficacy against current systemic chemotherapy regimens. In addition,

44 Plast Aesthet Res || Vol 1 || Issue 2 || Sep 2014