1. Trichology
Study of hair

2. Root Located below the surface of the epidermis 5 main structures
Follicle
Bulb
Dermal Papilla
Arrector pili muscle
Sebaceous (oil) Glands

3. Root fits over Dermal Papilla

4. Hair Root and Shaft

5. Hair follicle Tube like depression that encases the hair root
Inserted into scalp at differing angles
Inserted deep in the dermis
Creates the hair stream ( parts)
Distributed all over body
Except palms and soles
more than one hair will grow in a follicle

6. Bulb and Dermal Papilla
Lowest part of the hair strand
Thick, club-shaped structure- forms the lower part of the hair root
Dermal Papilla
Small, cone-shaped elevation
Located at base of the hair follicle and fits into the hair bulb

7. Cool Fact
The Arrector Pili muscle is small and works involuntarily at the base of the hair follicle. Strong emotions like fear or extreme cold cause it to contract, making the hair stand straight up…..otherwise known as “goose bumps”

8. Structure (cuticle) Cuticle- outer covering of hair
Consist of single over lapping layer of transparent scale like cells
Looks like shingles on a roof
Barrier that protects inner structure: cortex
Responsible for shine silky and smooth look
Haircolor and chemicals relaxers must have an alkaline pH to penetrate the cuticle layer

9. Structure (cortex)
Cortex-fibrous protein core formed by elongated cells containing melanin
middle layer; respon. for hairs weight(90%)
The elasticity of hair comes from cortex
The changes involved in oxidative haircolor, wet setting, thermal styling, permanent waving and chemical hair relaxing take place in cortex

10. Structure (medulla) Medulla is the innermost layer of the hair
Composed of round cells
Fine and blond hair may lack a medulla
All male beards contain a medulla
Salon services do not involve the medulla

11. Keratinization Hair composed of protein: approx. 90 %:keratin
Living cells within follicle begin to move up the hair follicle
They mature; process called keratinization
After cells fill with keratin they move upward
They lose their nucleus, and die
The emerge from follicle as nonliving fiber

12. Keratinization cont.
The protein is made up of long chains: amino acids
Which are made of elements called COHNS
Carbon, oxygen, hydrogen, nitrogen, sulfur
Proteins are made of long chains of amino acids

13. Amino Acid Units of structure that build protein
Linked together in long chains, like pop beads
Peptide (end) bond-chem bond links 2 amino acids
Chemical bonds that join amino acid is a peptide bond: also known as end bonds
Long chains of amino acids linked by peptide bonds make up the polypeptide chain

14. Polypeptide Chain

15. Chemical Composition of Hair
COHNS
Carbon 51%
Oxygen 21%
Hydrogen 6%
Nitrogen 17%
Sulfur %

16. Hydrogen weak physical side bond
easily broken by water or heat; however, numerous and so account for 1/3 strength
6% can be found in normal hair
Bonds can be reformed when the hair dries

17. Salt relatively weak; however, numerous and so account 1/3 strength
Strong alkaline or acidic solutions will break bonds
Reformed when the pH has been reformed

18. Disulfide -chemical bond; different from physical side bonds;
fewer in number but stronger
account for 1/3
not broken by heat or water
chemicals like permanent waves and chemical hair relaxers change hair's strength
change hairs disulfide bonds
reformed by thio neutralizers
disulfide bonds broken by chemical relaxers are broken permanently

19. Disulfide cont.
Disulfide bond joins sulfur atoms of two neighboring cystein (sis ti een) amino acids to create one cystine
Cystine joins two polypeptide strands

20. Hair Pigment pigment located in the cortex:melanin
melanin is tiny grains of pigment
gives natural color to hair
two types melanin
pheomelanin- red to ginger to yellow/blonde tones
Eumelanin- brown and black color to hair

21. Wave pattern shape of hair strand
any type of hair can occur in all races
round cross sections usually straight
oval cross sections wavy or curly
extremely curly hair
grow long twisted chains
varies in shape and thickness along length
as opposed to straight- uniform diameter

22. Terminal and Vellus Hair
Long , course, pigmented hair found on the scalp, legs, arms, and bodies
With the exception of gray hair, it is pigmented
Usually has a medulla
Vellus or lanugo hair
Short, fine, unpigmented, and downy hair on the body
Almost never has a medulla
Commonly found on infants and sometimes on children until puberty

23. Growth Phases Anagen = The growing phase Catagen- Transition phase
Average growth = 2 inches per month
90% of hair is growing at one time
Grows for period of 2-6 yrs
Duration is affected by age, gender, nutrition, health and your genes
Grows faster on:
Woman than men
Between ages and slowest after 50!
Catagen- Transition phase
Ends the growth phase
Lasts only one to two weeks
Follicle canal shrinks and detaches from the dermal papilla
Hair bulb disappears and the shrunken root end forms rounded club
Less than 1% in this phase at a time
Telogen
Follicle begins a 3-6 month resting phase
About 10% of hair is in this phase at any one time

24. Phases of Hair Growth

25. Terminal and Miniaturized Hair

26. Hair Myths Shaving or cutting hair has no effect on growth
Scalp massage will not increase hair growth. It may increase circulation. Minoxidil and finasteride are only treatments proven to grow hair. Women can not take finasteride: birth defects
Gray hair is exactly the same texture as pigmented hair
Race- all races have all hair types

27. Hair Loss Androgenetic alopecia Alopecia areata
Loss due to miniturization of terminal hair that is turned into vellus hair
Result of genetics, age, hormonal changes
Can begin as early as teens but frequently seen by the age of 40
Alopecia areata
Auto-immune disorder
White blood cells stop the hair growth during the Anagen Phase
Highly unpredictable skin disease
Affects about 5 million people in the US alone!
Starts with 1 or more small, round, smooth bald patches

28. Hair loss cont.
Alopecia areata may lead to complete body hair loss (Alopecia Universalis)!
Postpartum alopecia
Temporary loss at the end of a pregnancy
Little to no hair loss during the pregnancy leads to massive shedding from 3-9 months after baby
Returns to normal within one year after delivery

29. Alopecia Areata

30. Hair Loss treatments Minoxidil Finasteride
Topical medication applied to the scalp 2x’s a day
Proven to stimulate hair growth
Sold over the counter in 2 strengths
2% regular
5% extra strength
No known side effects
Finasteride
Oral prescription for men only
Side effects:
Weight gain and loss of sexual function

31. Hair disorders Canities
Greying of the hair: cause= loss of natural pigment in hair
1. Congenital- at or before birth
2. Acquired- due to old age, may occur prematurely in early adult life. CAUSE: worry, anxiety, nervous strain, prolonged illness
Ringed hair- alternating bands of grey/dark hair
Hypertrichosis- also known as hirsuties
Superfluous hair; terminal grows in areas that vellus hair would typically grow
Trichoptilosis- split ends
Trichorrhexis nodosa- knotted hair
Dry brittle condition that causes the hair to swell along the strand
Breaks easily which causes a brush like spreading of the hair
Monilethrix- beaded hair
Breaks between the beads or nodes
Fragilitis crinium- brittle hair

32. Canities

33. Disorders of the Scalp Pityriasis Two Types: Dandruff
Small white scales that appear on scalp and hair
Excessive shedding and accumulation of surface cells
Caused by: Melassezia fungus
Present on all skin but makes dandruff when it grows out of control
Two Types:
Pityriasis capitas simplex
Pityriasis Steatoides

34. Pityriasis 2 Types Pityriasis capitis simplex Pityriasis steatoides
Dry type; itchy scalp
White scales that attach to the scalp and hair strands or scattered loosely in the hair
Pityriasis steatoides
Greasy or waxy type
Scales become mixed with sebum; they stick to the scalp in patches
Medical treatment is advised
If redness and inflammation, medical term is “seborrheic dermatitis

35. Pityriasis Capitis classic type; large flakes itchy scalp

36. Pityriasis steatoides waxy, oily type

37. Pityriasis Steatoides

38. Shampoo for Scalp Disorders
Contain:
Pyrithione zinc,
Seleiuem sulfide, or
Ketoconazole
**All to control dandruff by suppressing growth of malessezia

39. Fungal Infections Tinea Tineas favosa Technical term for ringworm
Caused by vegetable parasites
Highly contagious!!
Begins with small, reddened patch of little blisters
Refer to a physician
Tineas favosa
Honeycomb ringworm
Dry, sulfur-yellow, cup-like crusts on the scalp called scutula
Give off odor
Scars from favus are pink or white, shiny bald patches
VERY contagious!!

40. Tinea Favosa

41. Tinea Cont’d Tinea Capitis Ringworm of the scalp
Characterized by red papules or spots at the opening of the hair follicles
Causes hair to break

42. Tineas Capitis

43. Parasitic Infections Scabies Pediculosisi Capitis Highly contagious
Caused by the itch mite
Vesicles and pustules form from the irritation of scratching
Pediculosisi Capitis
Head lice
Itching and scratching can cause infection

44. Pediculosis Capitis

45. Faruncles and Boils Faruncle or boil Carbuncle
Staphylocci infection of hair follicle
Produces constant pain
A pustule perforated by a hair
Refer to physician
Carbuncle
Inflammation of the subcutaneous tissue
Caused by staphylococci
Larger than a faruncle

46. Faruncle

47. Carbuncle

48. Texture medium- fine- coarse- most common
standard to which all others are compared
does not pose any problems
Thinner than coarse and thicker than fine
fine-
smallest diameter and more fragile
susceptible to damage: chemicals easier to process
coarse-
largest diameter
requires more processing than medium or fine hair

49. Hair Density Hair texture diameter of individual hair
Density refers to the number of
hairs per square inch
not very dense
Very dense

50. Density
Measures the number of individual hair strands per 1 square inch: Avg Head = 100K strands
Low Density
Thin Hair
Medium
Average or normal numbers per sq inch
High
Dense or thick

51. Density in Different Natural Colored Heads
Average head- 2,200 hairs per sq inch
Blondes- 140,000
Brown- 110,000
Black- 108,000
Red- 80,000

52. Porosity Hair Porosity= is the ability to absorb moisture
directly related to condition of the cuticle layer
healthy hair has compact cuticle which is naturally resistant to penetration
Three types:
Low
Average
High

53. Porosity cont. average porosity low porosity considered resistant
Normal Hair
slightly raised cuticle
chemicals usually process as expected
low porosity considered resistant
hair w/low porosity harder to process: chemicals
Requires more alkaline solution chemicals
Considered resistant
high porosity or overly porous
often result of previous over processing
damaged, dry, brittle
requires less alkaline with lower pH
So you don’t damage the hair further!

54. Elasticity ability to stretch and return to original shape
indication of the strength of side bonds
Hair with normal elasticity stretches:
wet up to 50%
dry stretches 20%
low elasticity
breaks easily
may not hold curl from setting, styling or permanently waving
chemical processing require mild solution/ low pH

55. Elasticity Test Test individual hair strands from 4 areas of the scalp
Hold wet hair and pull to stretch
returns to normal shape: good elasticity
if breaks or fails to return to original shape: low elasticity

56. Hair Growth Patterns Hair Stream Whorl Cowlick
Hair flowing in the same direction
Result of the follicles sloping in the same direction
Two streams flowing in opposite direction create a part!
Whorl
Hair that forms in a circular pattern, as in on the crown
Cowlick
A tuft of hair that stands straight up
Can be anywhere on the scalp but more noticeable on the hairline

58. Compare and Contrast Hair Porosity to Hair Elasticity
Hair Texture to Hair Density
Dry hair and scalp to Oily hair and scalp