Skin is a remarkable organ of the body which is able to perform various vital
functions. It can mould to different shapes, stretch and harden, but can also
feel a delicate touch, pain, pressure, hot and cold, and is an effective
communicator between the outside environment and the brain
It is complex organ system of the body.
It double layered sheath , cushioned by the underlying
subcutaneous fat, which covers entire surface of body.
It is not uniformly thick.
The average thickness of the skin is about 1 to 2mm.
In the sole of the foot, palm of the hand & in the
interscapular region –thick(5mm)
Thin over the eyelids.
Skin makes up to 12-15% of an adult's body weight. Each
square centimeter has 6 million cells, 5,000 sensory
points, 100 sweat glands and 15 sebaceous glands. It
consists of 3 layers: the epidermis (the outer layer), the
dermis ('true skin') and the subcutaneous (fat) layer
Functions of skin
There are 6 skin functions:
Sensation - the nerve endings in the skin identify touch, heat, cold, pain and light
Heat regulation - the skin helps regulate the body temperature by sweating to
cool the body down when it overheats and shivering creating 'goose bumps' when
it is cold. Shivering closes the pores. The tiny hair that stands on end traps warm
air and thus helps keep the body warm.
Absorption - absorption of ultraviolet rays from the sun helps to form vitamin D
in the body, which is vital for bone formation. Some creams, essential oils and
medicines (e.g. HRT, anti-smoking patches) can also be absorbed through the skin
into the blood stream.
Protection - the skin protects the body from ultraviolet light - too much of it is
harmful to the body - by producing a pigment called melanin. It also protects us
from the invasion of bacteria and germs by forming an acid mantle (formed by
the skin sebum and sweat). This barrier also prevents moisture loss.
Excretion - Waste products and toxins are eliminated from the body through the
sweat glands. It is a very important function which helps to keep the body 'clean'
from the inside.
Secretion - sebum and sweat are secreted onto the skin surface. The sebum keeps
the skin lubricated and soft, and the sweat combines with the sebum to form an
acid mantle which creates the right ρH balance for the skin to fight off infection.
Structure of skin
Skin is made up of three layers namely;
2.Dermis (which consists of connective tissue)
The two are separated
by a lamina, the
It consists of two main elements :
the epithelial cells & the pigment
The epidermis of the skin is
formed by stratified squamous
epithelium, the epithelial cells are
arranged in 5 layers,
1. Stratum corneum,
2. Stratum lucidum,
3. Stratum granulosum,
4. Stratum spinosum &
5. Stratum germinativum
The dermis is the layer responsible for the skin's structural
integrity, elasticity and resilienceThe dermis consists of
Superficial or papillary layer
Contains widely separated, delicate, collagenous elastic
and reticular fibers run vertical to the surface, in meshed
with capillaries and surrounded by ground substance.
Deeper reticular layer contains sebaceous glands, sweat
glands, hair follicles and a small mumber of nerve and
muscle cells. Sebaceous glands, based around hair follicles,
produce sebum, an oily protective substance that lubricates
the skin and hair and provides protection by forming an acid
mantle when mixed with sweat
Subcutaneous tissue is the deepest layer of the
skin located under the dermis and consisting
mainly of fat cells. It acts as a shock absorber
and heat insulator, protecting underlying
tissues from cold and trauma. The loss of
subcutaneous tissue in later years, leads to
facial sag and makes wrinkles more visible. To
counteract it, a cosmetic procedure where fat is
taken from elsewhere in the body and injected
into facial areas, is common these days.
Most superficial layer
Consists of dead cells – Corneocytes
The epithelial cells lose their nucleus.
The cytoplasm is flattened with fibrous protein
known as keratin.
A clear band, separate this layer from the outer
layer of epidermis.
Made up of flattened epithelial cells.
Cells have degenerated nucleus.
More superficially, the cytoplasm of the cells
contains granules, the area is known as the stratum
In the stratum spinosum / prickle cell layer, which
is superficial to the basal layer, the cells are larger
and are joined by tiny fibrils known as tonofibrils
Deepest layer with irregular, tall, columnar cells.
Attached by hemidesmosomes to basal lamina.
Doesn’t stain with H& E.
Proliferates & synthesizes intermediate filaments/
As these cells pass through next layer,
tonofilaments form bundles called tonofibrils.
The dermis consists of
two layers :
Superficial or papillary layer
Contains widely separated,
elastic and reticular fibers
run vertical to the surface,
in meshed with capillaries
and surrounded by ground
A deep / reticular layer
Dense, coarser, branching, collagenous fibers
arranged in layers mostly parallel to the surface.
Connective tissue cells
An irregular wavy line ; the
ridges / rete pegs projects into
the dermis, enclosing between
them the vascularised dermal
The cells of the basal layer of
the epidermis are attached to
the basement membrane, a
connective tissue layer, by
of the epithelium, in the
form of eccrine sweat
glands & pilosebaceous
units which in certain sites
include apocrine glands,
penetrate into the dermis.
structures are collectively
called the Adnexa.
HAIR FOLLICLES :
Cells of developing
epidermis invade the dermis
development to form
structures; the hair follicles,
sebaceous glands, and sweat
Hair follicle extends into the
dermis to a varying depth,
towards its deepest part it
expands to form hair bulb.
Most sebaceous glands are
appendages of hair
follicles and open inside
the pilosebaceous canal.
They are generally found
on the underside of the
The lobules of sebaceous glands are solid masses
of cells that gradually become filled with fat
granules and finally disintegrate, giving forth an
oily secretion known as sebum.
This provides lubrication for the hair, keeps skin
supple, protects it against friction, and makes it
more impervious to moisture.
Eccrine sweat glands are
found over the general
These are simple, tubular glands, usually coiled at
the base of the dermis.
The ducts of the sweat glands pass through the
epidermis and open either at sweat pores on the
skin surface or above the opening of sebaceous
glands in the hair follicles walls.
Melanocytes: the cells
production of pigment
in the epidermis.
Lie among the cells of
the basal layer
CLINICAL IMPLICATION :
Transplanted skin temporary severed from the nerve
connections, lacks the lubrications normally
supplied by the eccrine and apocrine glands and is
therefore dry and more susceptible to injury.
Bland creams, such as lanolin / cocca butter, should
be applied to grafted skin until reinnervation and
function of the secreting glands are restored.
Place incisions along the borders of aesthetic units rather
than across them.
When excising lesions from the face, the best results often
are obtained by excising a complete aesthetic unit and
replacing it with a skin graft, even if this increases the amount
of skin removed when compared to what is required to
achieve an adequate margin around the lesion.
Postauricular area is preferred in men. For FTSG
In contrast preauricular skin in females is preferred source
as it is hairless & has more solar aging. For FTSG
skin varies in thickness based on its anatomic location and
the sex and age of an individual.
Skin is thickest on the trunk, palms and soles of the feet,
while the thinnest skin is found on the eyelids and in the
Male skin is characteristically thicker than female skin in
all anatomic locations.
Children have relatively thin skin.
This thinning is primarily a dermal change, with loss of
elastic fibers, epithelial appendages and ground substance.
Dermis thickens up to 4th or 5th decade.
Skin grafts –
Skin transplanted by
completely detaching a
portion of integument from its
donor site and transferring it
to a host bed, where it
acquires a new blood supply
to ensure the viability of the
A skin graft is a tissue of
epidermis and varying
amounts of dermis that is
detached from its own blood
supply and placed in a new
area with a new blood supply.
Skin flaps – Defined as a
portion of skin and
subcutaneous tissue which is
raised from the donor site –
the flap is left attached to the
surrounding skin by a
Skin grafts Skin flaps
a. Full thickness
b. Split thickness
c. Pinch graft
Free skin grafts are pieces of skin that have been
served from their local blood supply and
transferred to another location.
Free skin grafts are divided into 4 categories
STSGs Composite graft Free cartilage
graftComposed of full
Consists of cartilage with
Type of Graft Advantages Disadvantages
-Least resembles original skin.
-Least resistance to trauma.
-More qualities of
-Lower graft survival
-Most resembles normal
-Resistant to trauma
-Donor site must be closed
-Donor sites are limited.
Full thickness graft Split thickness graft
If adjacent tissue has
premalignant or malignant
lesions and precludes the
use of a flap.
Specific locations that
lend themselves well to
FTSGs include the nasal
tip, helical rim, forehead,
eyelids, medial canthus,
concha, and digits.
Used when cosmetic
appearance is not a
primary issue or when the
size of the wound is too
large to use a full
CUTTING : FULL-THICKNESS GRAFT vs SPLIT
Cut free-hand with a scalpel; no
dermatome is used.
Usually a pattern of the defect to
be grafted is made and
transferred to the donor site
where it is outlined.
A variety of dermatomes are
available for cutting split-
Air/electric powered dermatomes
The free hand knife are used to
cut lengthwise on the extremity;
Drum dermatomes are used
sidewise across the extremity.
Humby knife as modified by Blair
Other skin graft knives are
The Blair-Brown knife
The watson knife
The cobbett knife
Silver’s Miniature Knife.
The most critical component of successful skin grafting is
proper wound preparation.
Failure to establish optimal physiologic conditions to
accept and nourish the graft is the source of most graft
Skin grafts will not survive on tissue with a limited blood
supply, such as bone, cartilage, tendon, or nerve.
Skin grafts will survive on
Muscle and Granulation tissue.
Wounds secondary to radiation also are unlikely to support
Chronic wounds must be free of pus and should have –
healthy, pink to beefy red appearance with an ideal wound
pH – 7.4
Epithelial migration at the edges of the granulation
surface may sign that wound is ready for skin graft.
The wound also must be free of necrotic tissue and
relatively uncontaminated by bacteria.
Bacterial counts greater than 100,000 per square
centimeter are associated with a high likelihood of graft
To achieve an adequate wound bed
Dressing changes, and
Topical or systemic antibiotics - prior to
Careful operative technique is necessary to maximize graft
After initiation of appropriate anesthesia, the wound first is
prepared for grafting. This includes
Cleansing of the wound with saline or diluted
Judicious debridement and
Hemostasis may be achieved through
Application of a topical vasoconstrictor or
These grafts do not contract
and do not change in colour
or skin texture.
site for survival.
Lifespan of FTSGS when
wrapped in gauze ,
moistened in saline & stored
in fridge at 4 degree Celsius
is 3 weeks.
FULL-THICKNESS SKIN GRAFTS
The wound pattern - outlined over the donor region -
enlarged by 3-5% to compensate for primary contracture, which
will occur due to the elastic fiber content of the graft dermis.
The donor site - infiltrated with local anesthetic with or
After incising the pattern, the skin - elevated with a skin
hook, keeping a finger of the nonoperating hand on the
epidermal side of the graft.
This provides tension and a sense of graft thickness while the
operating hand dissects the graft off of the underlying
Any residual adipose tissue - trimmed from the underside of
the graft because this fat is poorly vascularized and will prevent
direct contact between the graft dermis and the wound bed.
Trimming of residual fat is best accomplished with sharp
curved scissors with the graft stretched over the nonoperating
hand until only the white glistening dermis remains.
Grafts may be pie-crusted to allow egress of wound fluid
from beneath the graft.
These openings will not prevent graft loss from an
This technique - performed by making multiple stab
wounds through the graft with a number 15 scalpel blade.
Once the graft is harvested reinspect the recipient site for
Place the graft with the dermal side down over the wound
Also take care to prevent wrinkling or excessive stretching
of the graft.
The graft then must be secured in place to provide stability
during initial adherence and healing.
Absorbable sutures are preferable because they do not
Usually, 4 corner sutures are placed to hold the graft in the
Then a running suture is placed around the periphery.
Perfect epidermal-to-epidermal approximation ensures
optimal cosmetic results.
A dressing is chosen - provide uniform pressure over the
entire grafted area through a nonadherent, semi-occlusive,
absorbent dressing material.
Immobilize the graft,
Prevent shearing and
Prevent hematoma formation beneath the graft.
Another dressing choice for an irregularly contoured
wound or wound with high levels of exudate - vacuum-
assisted closure (VAC) sponge.
It conforms to the wound surface by suction and promotes
skin graft adherence on removing exudate and edema from
Finally, the graft may be treated open by placing no
dressing except a layer of ointment to prevent desiccation.
This technique - susceptible to hematoma or seroma
formation beneath the graft because no pressure is applied.
This technique is used only occasionally in facial grafting.
Graft adherence - maximal in the first 8 hours postgrafting
but the initial dressing left in place for 3-7 days unless pain,
odor, discharge occur.
An initial adherence to the wound bed via a thin fibrin
network temporarily anchors the graft until definitive
circulation and connective tissue connections are established.
Begins immediately and probably is maximized by 8 hours
The period of time between grafting and revascularization of
the graft - the phase of plasmatic imbibition.
The graft imbibes wound exudate by capillary action through
the spongelike structure of the graft dermis and through the
dermal blood vessels.
This process is entirely responsible for graft survival for 2-3
days until circulation is reestablished.
During this time, the graft typically becomes edematous and
increases in weight by 30-50%.
Revascularization of the graft begins at 2-3 days.
Inosculation is the establishment of direct anastomoses
between graft and recipient blood vessels.
Full circulation to the graft is restored by 6 or 7 days.
Plasmatic imbibition, and
Scularization, the graft will not survive.
Wound contraction may present serious functional and
cosmetic concerns - depending on location and severity.
On the face, it may produce
Retraction of the nasal ala or
Distortion of the vermilion border.
Contraction - begins shortly following initial wounding,
progressing slowly over 6-18 months following grafting.
Myofibroblast is believed to be responsible for this
Deep dermal component is able to suppress myofibroblast
Hair - more likely to grow from full-thickness grafts than
from split-thickness grafts.
Sweat glands and sebaceous glands initially degenerate
Sweat gland regeneration - dependent on reinnervation of
the skin graft with recipient bed sympathetic nerve fibers.
Sebaceous gland regeneration - independent of graft
reinnervation and retains the characteristics of the donor site.
skin graft - lacking normal lubrication of sebum produced
by these glands.
Grafts may appear dry and undergo scaling during this
Full-thickness grafts - soft and pliable with time as
sebaceous gland regeneration occurs.
Reinnervation of the graft occurs from the recipient bed
and from the periphery along the empty neurolemma sheaths
of the graft.
Full-thickness grafts reinnervate more completely than do
Pain usually is the first perceived sensation, followed later
by touch, heat, and cold.
Pigmentation returns gradually to full-thickness skin grafts.
Graft be protected from direct sunlight for at least 6 months
postgrafting or even longer.
Hyperpigmentation - treated with dermabrasion and laser
The most common reason for skin graft failure is
Hematoma beneath the graft.
Seroma formation may prevent graft adherence to the
underlying wound bed - preventing the graft from
receiving the necessary nourishment.
Movement of the graft or shear forces - lead to graft
failure through disruption of the fragile attachment of the
graft to the wound bed.
Poor recipient site.
Technical error also may yield graft failure.
Graft upside down will result in complete graft
Applying excess pressure,
Stretching the graft too tightly, or
Handling of the graft in other traumatic ways
MUCOSAL GRAFTS :
Full thickness mucosal grafts to reconstruct nasal
and conjunctival defects can be harvested from the
inner aspect of the cheek.
Care must be taken to avoid injury to the parotid
Other mucosal grafts
Nasal mucous membrane
To support a lower eyelid, a composite graft of
nasal mucous membrane with accompanying
septal cartilage may be removed.
Color and texture of grafted skin are optimally
More normal sweating and sebaceous activity
Less contour irregularities.
Contraction at recipient site is limited.
Hair is transferred with graft .
Graft in children will grow as the child grows.
SPLIT-THICKNESS SKIN GRAFT
Categorized further as
Thin (0.005-0.012 in),
Intermediate (0.012-0.018 in),
Thick (0.018-0.030 in),
based on the thickness of the harvested graft.
Require less ideal conditions for survival and have a much
broader range of application.
Resurface - large wounds,
- mucosal deficits
- muscle flaps
Line cavities and
Close flap donor sites
Donor sites heal spontaneously because of the remaining
epidermal appendages - reharvested once healing is complete.
They contract more during healing and do not grow with
They tend to be abnormally pigmented or hyperpigmented
particularly in darker-skinned individuals.
Abnormal pigmentation, and
Frequent lack of smooth texture and hair growth
make split-thickness grafts more functional than cosmetic.
Common sites include the
Upper inner arm is a cosmetically superior donor site.
Most commonly used technique involves use of a
Dermatome, which provides rapid harvest of large uniform-
thickness grafts. Dermatomes may be
Electric, used to cut lengthwise.
Free hand knife
Drum dermatomes – used sidewise across the
They require anesthesia – painful.
LA with adrenaline is preferred to reduce blood loss.
Rapidly oscillating side-to-side blade advanced over the
skin with thickness and width - surgeon preference.
Freehand With A Knife: (eg, Humby knife, Weck blade,
Disadvantages - grafts with irregular edges and
Air- or electric-powered dermatomes;
Most commonly used devices today.
The blade has a correct and an incorrect orientation
and inexperienced personnel may easily confuse the two.
Insertion of a No 15 blade scalpel simulates a
thickness of 0.015 inches and used to check depth
settings are uniform and correct.
It is useful to lubricate the skin and dermatome with
mineral oil - easy gliding of the dermatome over skin.
Dermatome is held at a 30- to 45-degree angle from the
donor skin surface.
Dermatome is activated and advanced in a smooth
continuous motion over the skin with gentle
Dermatome is tilted away from the skin and lifted off
of the skin to cut the distal edge of the graft and complete
The graft may then be gently washed of lubricant and
used for grafting with or without meshing.
Exposure of fat indicates graft was performed too
Thicker the graft – more opaque it is.
Ideal skin graft is slightly translucent.
Graft thickness – judged by type of bleeding – on donor site
Superficial graft – small bleeding points.
Deeper cutting – fewer bleeding points which bleed more.
Too deep graft – exposure of fat.
Used – Shaving scars where there is hypertrophy without
- Tangential excision of burns.
COMMONLY USED DERMATOMES
Small electric dermatome – for harvesting mucous
membrane grafts for reconstruction of
Motor moves – small cutting head with blade that
controls thickness of the cut.
Another small electric dermatome – Davol company with
Cutting blade on the small power dermatomes tend to
lose their sharpness rapidly.
It is a modification of the Padgett-Hood dermatome.
Accompanying set of shims – permits careful calibration
Disadvantage – if the graft is too thick or thin, it is
difficult to change the calibration in the middle of a skin graft
Once the procedure is over – remove the disposable blade
to avoid injury to the operator.
Graft is removed by gentle rubbing with a sponge gauze
soaked in normal saline solution.
When it become necessary to use a donor site such as
neck, chest or flank – inject normal saline until it becomes
level with the surrounding area.
It is lighter and can be used more rapidly.
There is now available a plastic tape with glue on both
Outer protective cover is removed from the tape and
latter is applied to the drum of the dermatome.
Thickness is to 0.004 inch to compensate for thickness
of the tape.
SELECTION OF DRUM DERMATOME
Reese dermatome provide – 7*4 inch graft cutting size.
Padgett dermatome – 8 inch long and comes in three widths.
Small – 3 inch wide.
Medium – 4 inch wide
Giant – 5 inch wide
Allow calibration while cutting is being accomplished.
Lighter and is easy to handle.
Depend on glue applied to both the drum and skin
It is a heavier instrument.
Use an adhesive tape applied to drum and a glue
applied to skin surface.
FREEHAND CUTTING STSG
All skin grafts are harvested with hand-held knives.
These are – long, sharp blades with an adapter over the
blade that facilitate
Cutting of the graft.
Controlled the graft thickness.
Allow cutting of very large pieces of skin.
Edges of the skin graft donor site were always irregular.
Large Humby-type knives are less used today but smaller
knives are often helpful in cutting small grafts.
Easy availability of Goulian-type knife or razor blade
should eliminate use of pinch grafts.
These grafts were thick at the center and thin on the
Primarily used in two situations
When there is insufficient skin – as in massive
burn in which skin graft must be
When a very convoluted surface must be covered
with a graft where a sheet might not
Disadvantage – expanded one difficult in healing.
Heal in b/w the expansion by epithelization.
Does not prevent loss of a graft from hematoma, if
bleeding in profuse at the time of skin grafting.
A semi-occlusive dressing is applied as there is
Less tendency for the graft edges to curl as they dry.
Less desiccation of the underlying wound.
Graft may be meshed by placing the graft on a carrier and
passing it through a mechanical meshing instrument.
Allows expansion of the graft surface area up to 9 times the
donor site surface area.
This technique is indicated when
Insufficient donor skin is available for large wounds,
as in major burns or
When the recipient site is irregularly contoured
and Adherence is a concern.
Allow wound fluid to escape through the graft.
Will not prevent graft loss due to underlying
Heal by re-epithelialization and may contract
Healed wound characteristically has a crocodile skin or
Because of secondary contraction and poor cosmesis, avoid
using this technique in the
Over joints, and
In other highly visible areas.
Take care to prevent wrinkling or excessive stretching of
The graft must then be secured in place to provide stability
during initial adherence and healing.
COMPOSITE GRAFTS :
Composite grafts are modified FTSGs consisting of
two or more tissue layers, usually composed of skin
Especially useful for repair of full thickness nasal
alar rim defects, nasal tip defects resulting in
cartilage loss, columellar defects.
Repairing of full thickness nasal mucosal defects.
DONOR SITES :
The auricular donor sites
most commonly used are
the helical crus, the helical
rim, the antihelix, tragus
and earlobe (skin and fat).
The helical crus provides a
good contour for grafting
of small alar rim defects
because it is straight and
does not have an anterior
The defect can be carefully measured and then
marked on the donor site, or a template can be
The recipient site on the alar rim must be de-
epithelialized and scar tissue removed to facilitate the
amount of surface area that gets exposed to the graft.
The graft is sutured in layers, starting with the
mucosal layer, using an absorbable suture. The needle
should pass through the mucosa and then thorugh the
graft edge, so that the knots are tied external to the
An ointment – coated nasal packing can be placed
gently in the nasal vestibule, and a light coat of
antibiotic ointment and handherent (telfla) dressing
are placed externally.
The perioperative use of antibiotics has been
suggested because of the high bacterial colorization
encountered in the perinasal area.
PINCH GRAFTS :
There are small full-thickness grafts.
Pinch graft can be harvested using Davol-Siman
dermatome or the weck blade.
Pinch grafts have traditionally been used as wounds
that are draining.
Treatment of the hypopigmentation in localized
areas of vitiligo.
It is used for lining of a mastoid cavity following
The donor skin is held with pickups and then lifted.
The elevated bit of skin is transected with iris
scissors or a scalpel.
Multiple grafts (usually les than 1cm) are harvested
and placed almost next to each other, and the spaces
in between heal by epithelialization.
The major drawback is the unsightly “HILLOCK”
surface irregularity when these grafts heal.
To overcome this drawback, Robinson proposed,
punch biopsy to obtain a specimen of uniform depth
by limitation of the downward force, thereby
limiting the depth to the deep dermis.
Avasular grafts-cosists of nasal septum & mucosa.
Useful for providing internal lining to replace the
conjunctive following total lower eyelid
Nasal septal cartilage replaces tarsal plate, mucosa
replaces the conjunctiva.
Dermal & fat grafts
Were formerly used for sunken defects around the
orbit & maxillary sinus following surgery.
GRAFT IMMOBILIZATION AND POST-OP CARE
In most cases of skin grafting – optimal dressing is bolus
or tie-over dressing.
It is fashioned by placing sutures around the periphery to
hold the graft onto the wound bed.
Facial sutures may be as close as 2 to 3 mm.
Tied sutures gently press the dressing down onto the skin
graft, which in turn presses onto the wound bed.
The main objective of the tie-over dressing is to ensure
contact b/w graft and host bed.
SKIN GRAFT INLAY METHOD:
Referred as the Stent dressing.
Skin graft wrapped around dental compound, the dermal
Skin graft outlay technique is III but involves tying of
sutures over the top of the combination of dental compound
and skin graft.
Ideal wound bed, without bleeding or fluid
Cooperative or sedated patient.
Limited motion is allowed to the patient.
Graft usually is pink, adherent and viable within 48 hrs.
Crusts appearing around the margin may be left in place
to allow natural separation.
Superior dressings have been shown to be of the
semiocclusive variety. These products have been shown to
Fastest healing rates ( 9 days to re-epithelialization),
Lowest subjective pain scores,
Lowest infection rates (3%), and
Are among the lowest in cost.
Advantage of being transparent - allows ongoing
inspection of the site - maintaining sterility.
Fluid collection - promotes moist wound healing - more
rapid healing rates and decreased subjective pain scores.
The rate of healing is proportional to the number of
epithelial appendages remaining and inversely proportional to
the thickness of graft harvested.
Hair rarely grows from split-thickness grafts.
Sweat glands and sebaceous glands initially degenerate
Sensation returns to the periphery of the graft and proceeds
Split-thickness grafts reinnervate more quickly.
Grafts may remain pale or white or may become
hyperpigmented with exposure to sunlight.
It is generally recommended that the graft be protected
from direct sunlight for at least 6 months or even longer
SKIN GRAFT’ TAKE’
After detaching of the skin graft from the donor site, it
becomes potentially a dead piece of tissue.
Its life span ,when wrapped in gauze, moistened in
saline and stored in a fridge at 4 degree centigrade. It
may be live for up to 3 weeks.
To survive permanently, it must be planted, become
reattached and obtain a new blood supply from its
new surroundings and the various processes involved
in achieving this are called ‘TAKE’
“THE THINNER THE GRAFT, THE BETTER
THE THICKER THE GRAFT, THE BETTER
Is by fibrin and capillary budding
Vascular bed is required
Good opposition essential
Well- covered bone is needed.
Is threatened by prior radiotherapy
Can be destroyed by fibrinolysing bacteria.
A skin graft adheres to its new bed by fibrin.
Supplies the immediate nutritional requirements in
the form of plasmatic circulation.
Outgrowth of capillary buds occurs that provide
circulation of blood in the graft- demonstrated at
Fibers grow into the fibrin, which convert the
adhesive clot into a more definite fibrous tissue
attachment that increases over the ensuing days so
that by 5 days reasonable anchorage has occurred.
Some organisms can destroy fibrin and prevent
the fibrin to facilitate adhesion.
Beta hemolytic streptococcus pyogenes and
staphylococcus aureus produces fibrinolysin.
SERUM IMBITION PHASE
When the graft is initially placed on the recipient
site, it is devoid of vascular connections and
depends on plasmatic circulation for fluid
This nutrion is provided by plasma exudates from
dilated capillaries in the host bed.
Immediately after application of the graft and
during the subsequent 24 hours, the blood vessels
of the grafts appear less filled with blood and are
not readily detected when compared with those in
the surrounding skin.
On the first day after grafting, many vessels in the
donor tissue show early evidence of distention and
are rapidly filled with static blood.
On the second day vessel distention
continues, but blood circulation has not
begun, although a sluggish flow of blood
may occasionally be seen in the peripheral
A slow flow of blood occurs in the graft
vasculature on the third or fourth day and
continues to improve until the fifth or sixth day.
The fibrin clot fixes the graft to the host bed.
On the fourth day after transplantation fibroblasts
infiltrate the fibrin net work.
By the seventh or eight day fibroblast infiltration
continues as the fibrin clot is resorbed.
Deep layers of the graft are anchored to the host bed
by the ninth day, with new vasculature and
fibroblasts integrated in the firm union.
The nerve supply to a transported skin graft is
completely served, leaving no sensation in the newly
Within 2 months, neural structures begin to
regenerate. The nerve fibres enter the graft through
the base and sides, following vacated neurilemmal
DONOR SITE HEALING:
These leave behind an open wound with no
Direct primary closure of the donor site after
Within the first 24 hours, epithelium begins to grow
from the epithelial remnants in the dermis such as
hair follicles, sebaceous glands, and sweat glands.
Epithelial migration also occurs at the wound
CAUSES OF GRAFT FAILURE :
Inadequate graft bed (poor vascularity)
Technical errors such as placement over
epithelizing wound, grafts cut too thick or too thin,
or upside-down graft
Poor storage of grafts.
BIOLOGICAL SKIN SUBSTITUTES
These biologic skin substitutes may be intended for
Permanent replacement or
As a temporary biologic dressing until
Permanent solution is available or
Normal skin regeneration and healing occur.
Serve multiple functions
Decrease bacterial counts and promote a sterile
Slow the loss of water, protein, and electrolytes.
Reduce pain and fever,
Help restore function,
Facilitate early motion.
Provide coverage of vessels, tendons, and nerves.
Ideal skin substitute is one with
Little or no antigenicity,
Lack of toxicity,
Tissue compatibility, and
Lack of disease transmission.
Cadaveric grafts and pig skin grafts are the historical skin
Cadaveric grafts: allografts or homografts - transplanted
from one organism to another within the same species.
Pig skin grafts: xenografts or heterografts - transplanted from
one organism to another of a different species.
The theoretical risk of disease transmission with cadaveric
grafts also exists.
Cultured epithelial cells also have been developed, both as
Autografts and Allografts.
Cultured epithelial autografts require biopsies of the patient,
followed by growth of these cells in culture.
Structural weaknesses of
As well as the theoretical risk of disease transmission.
Allograft dermis :
Not actually rejected by the body because it is rendered
immunologically inert during processing.
Body instead remodels and replaces it with a native
Bilayer collagen matrices:
Consist of a Porous spongelike lattice of bovine collagen,
Chondroitin-6-sulfate, and Glycosaminoglycans that serve as
the dermal substitute
Dermal substitute layer serves as a scaffold that facilitates
ingrowth of native fibroblasts and blood vessels with its
An overlying silastic membrane simulates the epidermis and
serves to seal the surface to reduce insensible fluid loss.
At about 3 weeks, the silastic layer may be peeled off and
replaced with cultured epithelial cells or thin split-thickness
Temporary - material designed to be placed on a fresh
wound (partial thickness) and left until healed.
Semi-permanent - material remaining attached to the
excised wound, and eventually replaced by
autogeneous skin grafts.
Permanent incorporation of an epidermal analog,
dermal analog, or both as a permanent replacement .
It is defined as tissue raised from donor site which is
made up of skin & a variable amount of the underlying
subcutaneous tissue but having its own blood supply.
It is used to reconstruct primary defect.
The transfer usually leaves a secondary defect
which is either closed by direct suture or covered with
a free skin graft.
Types of flaps
According to distance from the defect:
a. Local flaps
b. Distant flaps
i. Peninsular flaps
ii. Island flaps
iii. Free flaps
1.Axial pattern flap
It is based on a named artery for majority of blood supply that runs
within the skin superficial to the underlying muscle layer, parallel
to the overlying skin.
Good blood supply, because of which they can generally be raised
to a much greater length. Limited by available vessels
Random flap at distal tip
Midline forehead flaps
2.Random pattern flap
They are based on the rich perforating vascular plexus of the
They are random in their blood supply, but also random in their
Based on subdermal plexus
length:width of 3:1 or 4:1
A rotation flap requires that you make the defect into a
triangle, and then swing the skin around.
It has to rotate on a pivot point, the radius of the arc of
rotation being the line of the greatest tension.
Use rotation flaps on skin which has a good blood
They are particularly useful on the scalp, and
but are unsuitable below the knee where the
blood supply is poor.
Make a rotation flap three times bigger than
necessary, so as not to over estimate elasticity
of the skin
Large cheek defects greater than 3 to 4 cm in the
lower preauricular area where recruitment of the
upper posterior cervical skin is required for wound
(1) Parts of the body where a patient’s
Skin is tight, or his circulation is poor, as in his hand
and below his knee.
(2) Don’t make a rotation flap over bone
(other than the skull) or over tendon.
It has two only two sides ; thus, it lends itself to
placing one side in a border between aesthetic
regions of the face.
The flap is broad based, there its vascularity tends
to be reliable.
Great flexibility in the design & positioning of the
It refers to flap created by incisions that allow for a sliding
movement of the tissue.
It best works in area of greater skin elasticity.
Cheek advancement flap
Useful applications of advancement flaps
Unipedicle advancement flap(U-plasty)
Created by parallel incisions, which allow sliding
movement of tissue in a single vector toward a
Triangular skin excisions along the periphery of
Typically are designed with a ratio of defect
width-to-flap length of 1:3.
Bilateral unipedicle advancement flaps(H-plasty )
Helpful for repair of the central lips & chin
Disadvantage is long suture line.
In both cases , advancement flaps are incised on
opposite sides of the defect & advance toward
Two flaps don’t necessarily have to be of the same
First incise & elevate only one flap.
Advantage of bilateral flaps over a single flap for
repair of these midline structures is that equal pull
from the two opposing flaps lessens tissue
distortion & the propensity toward deviation of
midline structures toward one side.
Bipedicle advancement flaps
For large defects of the scalp & defects of lower third of
It has 90-110 degree
It is designed adjacent to the defect & is advanced into the
defect at a right angle to the linear axis of flap.
This leaves a secondary defect –repaired with split -
thickness skin grafts or by direct closure
1:1 length is to width ratio should be followed
It is made by moving a rectangle or square of skin
and subcutaneous tissue on a pivot point to cover
an immediately adjacent defect.
The end of the flap should extends beyond the
Rhomboid, dufourmental, bilobed
Its ability to harvest a flap at some distance from the
location of the defect.
It can be designed in a number of configurations to
adapt to irregular-shaped defects.
Ample quantities of subcutaneous fat may be left
attached to the under surface of the flap to assist with
filing of deep facial defects.
Lengthy flap relative to the width of the base can be
developed & this facilitates closure of the donor
defect without excessive wound closure tension.
Potential for developing a trap–door deformity. This
complication tends to occur a few weeks following
The rectangle or parabola-shaped transposition flap
is commonly used for repair of cutaneous defects of
the medial & lateral cheek, temple, & glabellar area.
It is based on an axial blood supply can be harvested
from the region of the forehead & medial cheek.
In the forehead, the flap is transferred with the
supratrochlear artery & vein.
It is used to repair a defect that has a configuration of a
rhombus with two opposing 60 degree & two opposing
120 degree interior angles.
The 60 degree to 120 degree can be thought of as two
equilateral triangles placed base to base.
Common skin & mucosal flaps in
Oral & Maxillofacial Surgery
Median forehead flap
Axial pattern - angular artery
Inferior and superior flaps
Uses - lower 2/3 of nose, perinasal
pin cushioning, blunting of nasofacial
potential ectropion, scleral show
Mid forehead flap
Median, paramedian forehead flap
Supratrochlear artery - at medial brow,
2cm from midline
pedicle can be as little as 1.2 cm
thin distal tip appropriately
long scar, limited length, revision
Posteriorly based –ashe’s flap
Anteriorly based – dharwad flap
Type of rotation flap
Based on greater palatine vessels
Post operative care
hydrogen peroxide, antibiotic ointment
Sutures removed at 5-7 days
Direct sunlight avoided for 2-3 months
Dermabrasion - 6-12 weeks
Revision/Irregularization - 6 months
A working knowledge of the indications, techniques,
donor site considerations, and post-operative
complications of all types of skin grafting is necessary
for soft tissue reconstruction.
As the incidence of skin cancer continues to rise,
increasing number of patients are likely to require
reconstructive planning, and attention to detail
preoperatively, intraoperatively and postoperatively,
optimal cosmetic and functional results using skin
grafting techniques can be achieved.