STRUCTURE, FUNCTION & ILLNESSES OF THE SKIN

1. STRUCTURE,
FUNCTION AND
ILLNESSES OF
THE SKIN

2. STRUCTURE AND FUNCTION OF THE
SKIN
Most people assume that the skin is just a smooth body
covering. However, if you look at a cross section of the skin
under a microscope, you will see three distinct layers: The
EPIDERMIS; the DERMIS; and the SUBCUTANEOUS
 Most people assume that the skin is just a smooth
body covering. However, if you look at a cross
section of the skin under a microscope, you will
see three distinct layers: The EPIDERMIS; the
DERMIS; and the SUBCUTANEOUS

3. THE EPIDERMIS
is the outer skin layer.

4. Papillae form a complex design on the finger tips.
The eye can detect small opening in the skin
surface called pores.
the top coat of the epidermis is composed of dead
cell. This cell layer shields the body from sun,
wind, harmful chemicals in the environment, and
injuries. It also prevent moisture from leaving the
body and forms a natural germ harrier. Beneath this
surface, the inner cell layers of the epidermis are
alive and active.

5. Melanin is made in the inner layers of the epidermis.
Melanin protect the skin against the harmful ultraviolet
ray of the sun. When exposed to the sun, the skin
produces more melanin and tans. Freckles are small
patches of melanin.
As new cells divide, older cells are pushed slowly to
the surface. As they journey upward, they produce
keratin. Keratin is a transparent, waterproof substance.

6. THE DERMIS
 The middle layer of skin.
 It is called the true skin because it houses the skin’s
vital structures.
 It contains a dense network of blood vessels.
 Protein fibers called collagen run through the
dermis, giving the skin strength and elasticity.

7. The glands found around hair shafts secrete an oil,
sebum. Sebum moves up through the duct around
the hair shafts and out of the pore at the surface of
the skin. It coats and lubricates the keratin layer of
the epidermis. This makes the skin more
waterproof and helps prevent water loss from the
body.
Sweat glands secrete perspiration, ridding the body
of excess water, salt, and other waste products from
the blood.

9. THE SUBCUTANEOUS LAYER
The deepest of the skin layers is the subcutaneous
layer. The body’s supplies of fat deposits are in this
layer. Every one male or female, fat or thin has fat
cells in the subcutaneous layer. This bottom layer
naturally insulates the body against heat and cold.
It also acts as an inner cushion to protect the body
against injuries. As the body ages, some fat is lost
from this layer. The skin shrinks unevenly and
causes creases and wrinkles.

10. COMPLEXION COMPLAINTS
Are you bothered by skin problem ? Skin problems
are among the most common complaints of adults
and teenagers. Proper care can help correct various
skin problems.
ACNE
Acne is one of the most common complexion
complaints, specially among teenagers.

11. BLACKHEADS

12. PIMPLES

13. ACNE SCAR

14. Four Types of Acne Scars

15. BOILS
A deep, serious infection that invades all layers of
the skin is called a boil. Boils can occur alone or in
groups anywhere on the body. Like pimples, boils
should never be squeezed. Boils require medical
attention. A doctor can drain pus fro the boil and
use antibiotics to control infection. Frequent or
numerous boils can be a sign that the body has lost
its ability to fight infection. Diabetes or other
disease may be the cause of the problem.

17. WARTS
often warts appear as raised growths on the skin.
Warts are caused by virus that can be picked up
anywhere. At present there is no drug that will
prevent warts. Warts can grow anywhere but are
most common on the face and hands. Warts can
spread from one person to another or from one area
to another on the same persons body. They usually
disappear spontaneously. However , if warts are
irritating or if they begin to multiply rapidly, a
doctor can remove them by a simple and painless
produce.

18. The word plantar means on the sole of the foot.
Plantar warts grow only one the sole of the foot.
Plantar warts cannot grow out from the skin
because your weight puts pressure on the sole of
your feet. If they grow into nerves, plantar warts
can be very painful. They can penetrate deeply and
can be easily infected. They should be immediately
treated by a doctor.

20. TYPES OF WARTS

21. SKIN SPOTS
White spots, called vitiligo are patches where the
skin fails to produce melanin. The cause is
unknown. Prescription drugs are available to treat
this disorder. However, it may be easier and more
practical to cover vitiligo with cosmetics

22. VITILIGO

23. MOLES
Are slight overgrowths of skin with excess
pigment. Most brown moles range in color from
light to dark brown. These moles are usually
harmless. However, black or blue black moles can
be dangerous. They can develop into a deadly skin
cancer at any time. Skin growths that grow rapidly,
change color, or bleed should be checked cat once.
Of course, if you have any unusual skin condition,
see a doctor.

24. MOLES

25. BURNS
 If you are outdoor, you should avoid getting skin
chaps & burns. Chaps and wind burns are caused
by overexposure to wind & cold. This exposure
dries the epidermis, causing it to become red &
irritated.

27. SKIN SCALES
 Psoriasis, is a skin that appears as patches of red,
raised skin and silver scales of dead skin. It is most
common on the scalp, elbow, knees & outer surface
of the arms & legs. It can last & short for a long
time, & it can occurs in cycles. Psoriasis seems less
severe in summer than in winter. This is because
the sun’s ultraviolet rays are stronger in the
summer. Ultraviolet lights seems to improve this
condition. The exact cause of psoriasis is unknown.
There is no cure but medical treatment can control
this condition.

29. ALLERGIES
 Allergy is a reaction of the body to a certain
substances. Allergies are highly individual. For
example, strawberries can be a dessert delight for one
person & the cause of an allergy for another .
 Allergy reactions range from mild to severe. In a mild
reactions, the skin & the soft tissues around the eyes &
nose can become itchy, red & swollen. Nausea,
vomiting & diarrhea can also be allergic reaction.
Severe allergic reaction can cause swelling of the
throat collapse of the circulatory system, heart failure
& even death.

30. Most allergies develop gradually. When the body is
first exposed to the substances, an allergic reaction
does not usually occur. With repeated exposures,
the body may develop a sensitivity. this means that
three will probably be an allergic reaction each
time the substance contacts the body if sensitive
increases, the reactions become m ore severe. Some
people are highly allergic to penicillin or other
drugs.

32. ECZEMA
Many people refer to eczema as specific disease.
But it is really an allergic reaction. Many substance
can produce eczema, but the reactions to each one
are similar. The skin becomes red, swollen, crusty
and scaly. Small blister also form and ooze a clear
fluid. Eczema often results when certain substance
contact the skin directly. This condition is called
contact dermatitis.

34. HIVES
Red, raised areas on the skin are an allergic reaction
called hives. Hives vary size and depth and are usually
very itchy. When severe reactions occur, giant hives
sometimes appear these are deeper and less defined
than ordinary hives. They can form on the skin and
membranes of the lips, mouth, throat, and larynx. Giant
hives in the throat and larynx can be very dangerous.
They can block the airway and cause death by
suffocation. The victim needs immediate medical
attention. Cause of hives are numerous and hard to
determine, hives are often caused by foods and other
substances, such as sulfa drugs and aspirin. Hives can
also caused by emotional states.

36. TEETH
 Your teeth play an obvious role in appearance.
They also have other important functions. Teeth are
helpful for clear speech. Certain sounds, such as
“s” and “th”, cannot be easily pronounced without
front teeth. Teeth are also important for grinding
food into small particles, so it can be more easily
digested. Teeth and gum problems can cause
unpleasant, ranging from bad breath to pain. If
teeth become infected the infection ca be carried to
other parts of the body.

38. STRUCTURES OF THE
TEETH
The visible portion of a tooth are the heck and crown.
Notice the crown appears above the gum and narrows
to form the neck. A hard white protective layer of
enamel cover the crown and neck. The root of the
tooth lies in a socket in the jawbone. Its outer covering
is called cementum. The tooth is anchored firmly in
the jaw by the fibrous periodontal membrane. Lying
beneath the enamel layer is a softer substances called
dentin. It forms the actual body of the tooth, and it
houses the pulp cavity. Blood vessels and nerves lie
inside the pulp cavity. They join the jawbone’s larger
nerves and blood vessels at the base of the roots.

39. PRIMARY TO PERMANENT
TEETH
Primary teeth, commonly called the baby teeth,
start arriving at about 6 months of age. They are
lost gradually over period of years, starting at about
age 6. the first tooth is usually a front tooth, or
incisor. By age two and one half. Twenty primary
teeth have arrived. Permanent tooth grow in the
jaws beneath the roots of the primary teeth. When a
permanent tooth’s root is well developed, the tooth
is ready to emerge. By the, the root of the primary
tooth is absorbed. As a rule, only the crown and
neck remain when the primary tooth is lost.

40. Adults have 32 teeth of four types. Each types performs a
separate job. The upper and lower permanent incisors cut
food. Directly behind there are four pointed cuspid or
canine teeth. They cut ant tear food. There are eight
bicuspids two on each side of the upper and lower jaws.
The bicuspid cut and crush food. Behind the bicuspid are
the molars, which grind food. If all the molars developed,
there 12 altogether, three on each side of the upper and
lower jaws. Molars first appear at age 6 or 7, they do not
replace primary teeth. They grow behind them. At about
age 12 the second molars develop behind the first ones.
Third molars known as wisdom teeth usually appear
sometime between ages (18 and 21).

42. DENTAL PROBLEMS
DENTAL DAMAGE. Dental caries, known as tooth
decay, is a common dental disease procedures holes,
called cavities, in teeth. Tooth decay can start close to
the gum line, or between teeth. Tooth decay can start
close the gum line, or between teeth or on the biting
surface of the molar. Tooth decay is not communicable
disease. It is caused by bacteria that are always in the
mouth. Bacteria, food residues, and saliva form a sticky
colorless film on the teeth called plaque (plak). The
bacteria in plaque use the sugar in food to form acids
and other byproducts that destroy tooth enamel and
irritate gums.

43. decay penetrates the enamel and spreads to the
dentin: as the cavity grows toward the pulp, the
tooth becomes more sensitive. When the decay
reaches the pulp and exposes a nerve, a toothache
starts. In the stage of decay, the bacteria in the
verve canal destroy the pulp. An abscess or pus
collection, forms at the base of the tooth. If not
treated, the infection can spread to other parts of
the body. A decayed tooth can be saved by
cleaning, medicating, and filling the cavity.

44. when tooth decay penetrates deeply into the pulp, a
tooth can often still be saved. Endodontics , commonly
called root canal therapy, is required. The dentist
removes the diseased nerve canal contests, cleans out
the infection, and sterilizes and fills in the canal. If
possible, teeth should always be saved. Although root
canal therapy removes the nerves and blood vessels in
the root canal, the tooth looks almost the same.
However, it may become brittle due to the loss of its
pulpal blood supply. For this reason, your dentist may
crown the tooth with gold or porcelain to help protect
it.

45. PERIODONTAL DISEASE
Periodontal disease. This disease, which can begin as
early as age five, is mainly caused by plaque formation.
When plaque is not removed daily, its harmful products
collect along the gums, irritating the gums. They
become red, swollen or tender, and bleed easily. As
plaque builds up, it hardens into a limelike substance
called tartar which pushes against the gums. Pocket
form between the gums and teeth where more plaque
can grow and further damage the tooth root. As
periodontal disease spreads, gum recede and pus forms.
Eventually the bony structures supporting the teeth are
destroyed. Then, teeth looosen and fall out.

47. STAGES OF PERIODONTAL
DISEASES

48. MALOCCLUSION
More and more adults, teenagers, and young
children are wearing braces because they look
forward to the improvement that braces produce in
the positioning of their teeth. Orthodontics is the
dental specialty that corrects malocclusion, which
ia an irregularity in the position and bite of teeth.

50. BEFORE AND AFTER

51. ORAL HYGIENE
Proper oral hygiene requires flossing and brushing
the teeth each day. A thorough cleaning removes
food particles and helps eliminate plaque before it
hardens into tartar. This is why a thorough cleaning
of the teeth at least once a day is essential

52. METHODS OF BRUSHING
TEETH

53. PROFESSIONAL HELP
Good dental care includes dental checkups at least
twice a year. Most cavities develop over several
months. Do not wait for a toothache before seeing a
dentist. The dentist can spots prolems before
serious trouble develops. To prevent periodontal
disease, a professional tooth cleaning called
prophylaxis is usually needed. It removes tartar
build up. The dentist may take an X ray of the teeth
to locate hidden trouble.

54. X-RAY OF A CAVITIES