Scaffolds Oral mucosa tissue engineering

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1 scaffolds

1.1 naturally derived scaffolds
1.2 fibroblast-populated skin substitutes
1.3 gelatin-based scaffolds
1.4 collagen-based scaffolds

1.4.1 pure collagen scaffolds
1.4.2 compound collagen scaffolds


1.5 fibrin-based scaffolds
1.6 hybrid scaffolds
1.7 synthetic scaffolds





scaffolds

a scaffold or matrix serves temporary supporting structure (extracellular matrix), initial architecture, on cells can grow three-dimensionally desired tissue. scaffold must provide environment needed cellular growth , differentiation; must provide strength withstand mechanical stress , guide growth. moreover, scaffolds should biodegradable , degrade @ same rate tissue regenerates optimally replaced host tissue. there numerous scaffolds choose , when choosing scaffold biocompatibiltiy, porosity , stability should held account. available scaffolds oral mucosa tissue engineering are:


naturally derived scaffolds

acellular dermis. acellular dermis made removing cells (epidermis , dermal fibroblasts) split-thickness skin. has 2 sides: 1 side has basal lamina suitable epithelial cells, , other suitable fibroblast infiltration because has intact vessel channels. durable, able keep structure , not trigger immune reactions (non-immunogenic).
amniotic membrane. amniotic membrane, inner part of placenta, has thick basement membrane of collagen type iv , laminin , avascular connective tissue.

fibroblast-populated skin substitutes

fibroblast-populated skin substitutes scaffolds contain fibroblasts able proliferate , produce extracellular matrix , growth factors within 2 3 weeks. creates matrix similar of dermis. commercially available types example:



dermagraft™
apligraf™
orcel™
polyactive™
hyalograf 3d™

gelatin-based scaffolds

gelatin denatured form of collagen. gelatin possesses several advantages tissue-engineering application: attract fibroblasts, non-immunogenic, easy manipulate , boost formation of epithelium. there 3 types of gelatin-based scaffolds:



gelatin-oxidized dextran matrix
gelatin-chitosan-oxidized dextran matrix
gelatin-glucan matrix
gelatin-hyaluronate matrix
gelatin-chitosan hyaluronic acid matrix.

glucan polysaccharide antibacterial, antiviral , anticoagulant properties. hyaluronic acid added improve biological , mechanical properties of matrix.


collagen-based scaffolds
pure collagen scaffolds

collagen primary component of extracellular matrix. collagen scaffolds efficiently support fibroblast growth, in turn allows keratinocytes grow nicely multilayers. collagen (mainly collagen type i) used scaffold because biocompatible, non-immunogenic , available. however, collagen biodegrades relatively rapidly , not @ withstanding mechanical forces. improved characteristics can created cross-linking collagen-based matrices: effective method correct instability , mechanical properties.


compound collagen scaffolds

compound collagen-based scaffolds have been developed in attempt improve function of these scaffolds tissue engineering. example of compound collagen scaffold collagen-chitosan matrix. chitosan polysaccharide chemically similar cellulose. unlike collagen, chitosan biodegrades relatively slowly. however, chitosan not biocompatible fibroblasts. improve stability of scaffolds containing gelatin or collagen , biocompatibility of chitosan made crosslinking two; compensate each other s shortcomings.


collagen-elastine membrane, collagen-glycosaminoglycane (c-gag) matrix, cross-linked collagen matrix integra™ , terudermis® other examples of compound collagen scaffolds.


fibrin-based scaffolds

fibrin-based scaffolds contain fibrin gives keratinocytes stability. moreover, simple reproduce , handle.


hybrid scaffolds

a hybrid scaffold skin substitute based on combination of synthetic , natural materials. examples of hybrid scaffolds hyaff® , laserskin®. these hybrid scaffolds have been shown have in-vitro , in-vivo biocompatibilities , biodegradability controllable.


synthetic scaffolds

the use of natural materials in scaffolds has disadvantages. usually, expensive, not available in large quantities , have risk of disease transmission. has led development of synthetic scaffolds. when producing synthetic scaffolds there full control on properties. example, can made have mechanical properties , right biodegradability. when comes synthetic scaffolds thickness, porosity , pore size important factors controlling connective tissue formation. examples of synthetic scaffolds are:



polyethylene terephthalate membranes (pet membranes)
polycarbonate-permeable membranes (pc membranes)
porous polylactic glycolic acid (plga)

historical use of electrospinning produce synthetic scaffolds dates @ least late 1980s when simon showed technology used produced nano- , submicron-scale fibrous scaffolds polymer solutions intended use in vitro cell , tissue substrates. use of electrospun lattices cell culture , tissue engineering showed various cell types adhere , proliferate upon polycarbonate fibers. noted opposed flattened morphology typically seen in 2d culture, cells grown on electrospun fibers exhibited more rounded 3-dimensional morphology observed of tissues in vivo.








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