Trichology

Tricology

Study of hair

Only part of the hair that is alive

Hair bulb

Purpose of hair

-adornment-protection from heat, cold, and injury

Primitive hair germ

Forms in basal layer

Basal layer

Works it's way down into lower layer of skin for nourishment

Start of sebaceous gland and arrector pili muscle

pulls the upper layer down with it, creating the root sheath

Hair follicle and papilla

Hair grows from the root sheath

Shape of hair follicle determines...

Shape of hair shaft

Straight hair

round follicle

Wavy to curly hair

oval follicle

tightly curled hair

Elliptical follicle

Hair root

Portion of hair inside the hair follicle under the skins surface

Hair fiber

Portion of the hair that extends above the skins surface

Papilla

Filled with capillaries that supply nourishment to the cells around it

Germinal matrix cells

-Undergo cell division-produce cells that keratinize and form 3 layers of hair

hair pulled from roots can grow back only if the...

Papilla is not destroyed

3 levels of hair

1. Cuticle2. Cortex3. Medulla

Cuticle

Outer covering of the hair shaft

Cortex

Second layer with unique protein structures

Medulla

Central core of hair shaft

sebaceous oil glands

Produces sebum to prevent hair and skin from becoming too dry

Sebum oil

Mixes with perspiration to form the acid mantle

Acid mantle

Protects cuticle of hair fiber and maintains the natural pH of hair and skin (5.5 pH)

Arrector pili muscle

Causes hair to stand on end when a person is scared or cold

Keritinization

-Process of cells changing shape, drying out and forming keratin protein-Once keritized, cells form the hair fiber are no longer alive

Hair is primarily composed of...

Protein

Amino acids coil around each other to become protein chains that form the...

Cortex

Twisting gives hair ability to...

Stretch

3 stages of hair growth

1. Anagen2. Catagen3. Telogen

Anagen stage

-active growth-attached to root sheth

Catagen stage

-brief transition-cell division stops

Telogen stage

-resting-not attached to root sheath

Hair growth cannot be effected by...

Exercise

3 factors of hair behavior

1. Hereditary 2. Environment3. Products or appliances

Heredity

Determines hair structure, color, shape, diameter

Environment

Affects absorption of moisture of air

Products/appliances

Affect structural organization of hair

Structural organization of hair

Fine, medium and coarse

Cuticle structure

Hard, resistant

Cortex structure

Soft, elastic

Higher cuticle/cortex ratio

more resistant

Lower cuticle/cortex ratio

easily molded

Melanocytes produce...

Melanosomes

Melanosomes contain...

The pigment melanin

Two types of melanin

eumelanin and pheomelanin

Eumelanin

Brown/black pigment

Pheomelanin

Red/yellow pigment

Melanin influences the resulting hair color by...

The amount, size, and distribution of one or both melanins

Total lack of melanin is...

Albinism

Gray hair reduces...

Melanin in cortex

AKA mottled hair

Gray hair

Gray hair can be caused by

Serious illness, emotional conditions, hereditary

Gray hair grows from...

Papilla with gray hair

Melanin in the skin protects...

Skin and hair from damaging sun rays

Texture of hair

Degree of coarseness or fineness of the hair fiber

Fine hair feels like...

Silk

Medium hair feels like...

Cotton

Course hair feels like...

Wool

Density of hair

Determines number of active hair follicles per square inch on scalp

3 density words used...

1. Light/thin2. Medium3. Heavy/thick

Porosity of hair

The ability of the hair to absorb moisture, chemicals, and liquid

Average porosity cuticle is...

Slightly raised

Resistant porosity cuticle is...

Flat

Extreme porosity cuticle is...

Raised

Uneven porosity cuticles are...

Mixed

Elasticity

Ability of the hair to stretch and return to its original length without breaking

Normal dry hair stretches

20% of its length

Wet hair stretches

40-50% of its length

Number of cuticle scale layers

7-12

Scales should lie flat along...

Healthy hair

Acid mantle lubricates the outermost layer of the cuticle and reduces...

Friction

Combing and brushing damages...

The cuticle

Abraded hair, abraded cuticle

AKA broken hair

Abraded hair is:

Cuticle becomes crackles and fried

Brittle Hair, Fragilitis Crinium or Trichoptilosis

AKA split ends

Brittle hair is:

Small cracks in cuticle deepen into cortex

Aquifer canities

AKA grayness

Monilethrix

AKA beaded hair

Monilethrix is:

Breaks in the hair between beads or nodes

Thichorrhexis, Nodosa, Knotted hair

AKA nodules

Thichorrhexis is:

Lumps/swelling along hair shaft

Plica polonica

AKA matting hair

Plica polonica is:

Mass of hair strands that cannot be separated

Pilli annulati

AKA ringed hair

Pilli annulati is:

Alternating bands of gray and dark hair

Ambras Syndrome

AKA hypertrichosis

Ambras syndrome is:

Abnormal coverage of hair on body

Superfluous hair

AKA hirsutism

Superfluous hair is:

Excessive amounts of hair in women

Scales

AKA psoriasis

Scales is:

Disorder; thick, crusty patches of red irritated scalp

Dandruff

AKA pityriasis

Dandruff is:

Disorder; chronic, excessive flaking, itchiness, tightness, irritation

Dry dandruff

AKA Pityriasis capitis simplex

Dry dandruff is:

Disorder; dry flakes which appear translucent

Greasy/waxy dandruff

AKA pityriasis steatoides

Greasy/waxy dandruff is:

Disorder; oily flakes combined with sebum, stick to scalp in clusters, yellowish

Leading cause of dandruff is fungus called...

Malassezia

Ringworm

AKA tinea

Ringworm is:

Disease; red, circle patch of blisters, caused by vegetable parasite

Ringworm of scalp

AKA tinea capitis

Ringworm of scalp is:

Disease; enlarged open hair follicles surrounded by clusters of red spots

Honeycomb ringworm

AKA Tinea Favosa or Favus

Honeycomb ringworm is:

Disease; dry, yellow encrusted areas, may have odor

Itch mite

AKA scabies

Itch mites are:

Disorder; red, watery vesicles, animal parasite burrowing under skin

Head lice

AKA pediculosis capitis

Head lice is:

Disorder; causes itching and eventually infection

Lanugo hair

Fine, silky hair covering body before birth

Vellum hair

Short, fine, non-pigmented hair that replaces lanugo hair

Terminal hair

Long, thick pigmented hair such as scalp and eyebrow hair

Average daily hair loss

40 to 100 strands

Alopecia caused by...

Fungal or bacterial infection or inflammatory disease of scalp

Androgenetic alopecia is...

Progressive shrinking or miniaturizing of inflammatory disease of scalp

Androgenetic alopecia in men...

-AKA male pattern baldness -horseshoe shaped fringe

Androgenetic alopecia in women...

-generalized thinning of crown-scattered hair thinning

Degree of hair loss evaluated by...

Pattern and density

Pattern of hair loss

Shape and location

Density of hair loss

How much hair is covering scalp in area

postpartum alopecia

temporary hair loss experienced at the conclusion of a pregnancy

Alopecia areata

Autoimmune disorder, sudden loss of hair in large or irregular patches

Alopecia areata totalis

Total loss of hair on the scalp

Alopecia Areta Universalis

Total loss of hair over entire body and scalp

Alopecia prematura

Baldness that occurs early in life

Telogen Alopecia

Premature shedding during resting stage

Traction for traumatic Alopecia

Hair loss from excessive pulling or twisting