HAIR
INTRODUCTION-
Hairs are keratinized elongated
structures derived from invaginations of
epidermis and project out from most of
the body surface
LENGTH, WIDTH AND GROWTH RATE-
Length : range from <1mm to > 1 meter.
Average uncut scalp hair : 25 – 100 cm.
(exceptionally 170 cm)
Width : from 0.005 to 0.06mm.
Growth rate: about 1 cm/ month (terminal hair).
Hair Growth-
Anagen—hair is actively growing; lasts up to 5 years
Catagen—hair is not growing; a resting phase
Telogen—follicle is getting ready to push the hair out; lasts
two to six months
Hair grows about 0.4 mm per day, or 1 cm per month
‡The process of hair growth has three phases:
‡Anagen: This is the active growth stage of the hair fiber and can last from 2- 7 years. At any given moment 80-85% of our hair is in the anagen phase.
‡Catagen: Sometimes referred to as the transitional phase, which is when hair growth begins to “shut down” and stop activity. It generally lasts 10- 20 days.
‡Telogen: This occurs when hair growth is completely at rest and the hair fiber falls out. At any given time, 10-15 % of our hair is in the telogen phase, which generally lasts 100 days for scalp hair. After the telogen phase, the hair growth process starts over again to the anagen phase.
Hair Damage-
‡Cuticle, the outer layer of the hair shaft, defines smoothness and shininess. The hair cuticle may get damaged by chemical processes, overexposure to sunlight (UV rays), too much heat from a dryer, abusive brushing and combing, over-chlorinated swimming pool water, etc.
‡
‡Damaged hair/cuticles should be treated well with conditioners because cuticles cannot repair themselves once damaged.
Hair Raising Facts:
‡An average scalp has 100,000-150,000 hairs (about 1000 per square inch)
‡Hair is so strong that each hair can withstand the strain of 100 grams (3.5 ounces). An average head of hair could hold 10-15 tons if only the scalp was strong enough!
‡Human hair grows autonomously, that is each hair is on its own individual cycle. If all our hair were on the same cycle, we would molt!
‡Hair has the highest rate of mitosis (cell division). An average hair grows 0.3 mm a day and 1 cm per month. 35 meters of hair fiber is produced every day on the average adult scalp.
‡Less than 4% of the world’s population has naturally red hair
‡Most people lose between 50-100 hairs per day
‡Over 50% of men by age 50 have male pattern hair loss.
‡Forty percent of women by the time they reach menopause will have female pattern (hereditary) hair loss.
‡Hormone imbalance and crash dieting can trigger temporary hair loss.
Information we want you to know:
•The average life span of hair is 4-6 years
•Everyone sheds 75-100 hairs per day
•Hair does not grow after death
•Eyebrows and eyelashes are replaced every 4-5 months
DEVELOPMENT OF HAIR -
Ectodermal origin-
1. Hair bud – develops from epidermis and penetrates the dermis.
2. Hair shaft – grows from cells in the centre of hair bud.
3. Inner root sheath – develops from cells in the
periphery of hair bud.
PIGMENTATION OF HAIR-
Hair color is determined by melanocytes.
Melanocytes are present in the bulb.
Melanocytes feed melanosomes mainly to
the medulla and cortex.
Melanocytic follicles produce melanin-
. eumelanin (dominant in brown-black hairs)
. phaeomelanin (dominant in red-blond hairs)
Mesodermal origin: Outer root sheath.
First hair come is lanugo hair at eyebrow and upper lip at twelve weeks of gestation
Greying of hair – due to decreased
number and activities of melanocytes.
Vitiligo – due to destruction of
melanocytes.
Albinism – due to inactivity of
melanocytes
ALOPECIA-
•Absence or loss of hair especially of the scalp.
•Pathophysiology of hair loss :
•
1. Production failure –
¨ Failure to produce or continue to
¨ produce a normal hair follicle.
2. Aberration of –
¨ Normal hair cycle.
¨ Production of a normal hair shaft.
3. Destruction of –
¨ Hair follicle.
•Abnormal hair loss
•Most common types
–Androgenic alopecia
–Alopecia areata
–Postpartum alopecia
–Over 63 million people in our country suffer from abnormal hair loss
Causes of Hair Loss-
ASSOCIATED DEFICIENCY;-
PROTEIN
VITAMIN B6
VITAMIN C
VITAMIN E
IRON
Poor circulation Stress
Thyroid disease High blood pressure
Iron deficiency Pregnancy
Liver malfunction Chemotherapy
B & vitamin deficiencies Skin Disease
Large doses of Vitamin A High fever
Cholesterol Sudden weight loss
Alcohol and caffeine Medications
Poor circulation Stress
Thyroid disease High blood pressure
Iron deficiency Pregnancy
Liver malfunction Chemotherapy
B & vitamin deficiencies Skin Disease
Large doses of Vitamin A High fever
Cholesterol Sudden weight loss
Alcohol and caffeine Medications
ASSOCIATED DISEASE-
Higher incidence of alopecia areata in
patients of-
1. Atopic dermatitis.
2. Autoimmune disease –
* SLE
* Thyroiditis.
* Myasthenia gravis.
* Vitiligo.
3. Lichen planus.
4. Down syndrome.
DIFFERENTIAL DIAGNOSIS-
1. Tinea capitis.
2. Trichotilomania.
3. Secondary syphilis
4. Congenital triangular alopecia.
5. Alopecia neoplastica.
6. Early lupus erythematosus.
DISORDERS OF THE SCALP
Øouter layer
~ shed
~ replaced by new cells
ØHealthy, normal scalp cells fall off naturally
~ small, dry flakes
~ without being noticed
Ødry scalp-(not dandruff)
~ flakes much smaller
~ less noticeable flakes
Øcontact dermatitis, sunburn, or extreme age
Øworse in cold, dry climates
Medical term for dandruff:
Pityriasis
Øexcessive production and accumulation of skin cells
Ølarge visible clumps of cells
dandruff is the result of a fungus called malassezia
Dry dandruff is the result of a sluggish scalp caused by:
• poor circulation
• lack of nerve stimulation
• improper diet
•emotional and glandular disturbances
•poor personal hygiene
Treatments include:
Ø antidandruff shampoos
Ø conditioners
Ø“medicated” topical lotions
Ø“Antiseptic” scalp lotions
Ø scalp treatments
Ø regular scalp massage
Add: medicated/antiseptic
“seborrheic dermatisis”
(if torn off bleeding or oozing of the sebum results)
•When accompanied by redness and inflammation is:
•Can be found in eyebrows/beards
•
•Client with these two conditions (Pityriasis steatoides and seborrheic dermatitis) must be referred to a physician for medical treatment
FUNGAL INFECTIONS (TINEA)-
TINEA
•ringworm
•itching, scales, and sometimes, painful circular lesions
•Several may be present at the same time
•A fungal (vegetable) organism is not an animal parasite
•All forms are contagious
•
•Easily transmitted
•
FYI: Infected skin scales and hairs that contain the fungi are known to spread the disease
•Bathtubs
•Swimming pools
•Unsanitary personal articles
•Practicing approved sanitation and disinfection procedures will help prevent the spread of this disease
Q. How do we determine what the amount of density is?
a. Use fingers to feel the hair
b. Look at the scalp area
c. Ask the client how dense they think their hair is
d. Ask another stylist to help us decide
HAIR POROSITY-
Øability of the hair to absorb moisture
Øcondition of the cuticle layer
Øcompact cuticle layer
~ resistant to penetration
referred to as Hydrophobic
(phobic---does not like)
Øporous hair/raised cuticle
~ easily absorbs moisture
~Referred to as Hydrophilic
(philic---attracted to)
Ølow porosity
~ resistant
~ more alkaline solution
~ longer processing time
Øalkaline solutions
~ raise the cuticle
Øpermit uniform
~ saturation and processing
ØHigh porosity
~ overly porous
result of over processing
damaged
~ dry
~ fragile and brittle
less alkaline solutions (lower pH)
DRY HAIR AND SCALP-
Ø inactive sebaceous glands
Ø dry climate
Øhair appears dull, dry and lifeless
Ø moisturizers and emollients
ØAvoid frequent
shampooing
ØAvoid
~ strong soaps
~ detergents
~ products with high alcohol content
ØDry hair
~not overly-porous
OILY HAIR AND SCALP-
Causes:
Øgreasy buildup on scalp
Øoily coating
Øimproper shampooing
Øoveractive sebaceous glands
Ønormalizing shampoo
ØWell-balanced diet
ØExercise
ØRegular shampooing
ØGood personal hygiene
will control oily hair and scalp
Healthy Hair, Happy Clients