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Trichology. Trichos= Hair Ology=the study of Trichology is the study of Hair. Prepared by: Steve Ellis. Hair Analysis Wave Pattern and Tendencies. Hair texture is the thickness or diameter of the individual hair strand Hair texture can be classified as course, medium and fine.
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Trichology Trichos= Hair Ology=the study of Trichology is the study of Hair
. • Prepared by: Steve Ellis
Hair AnalysisWave Pattern and Tendencies • Hair texture is the thickness or diameter of the individual hair strand • Hair texture can be classified as course, medium and fine
Story of the Strand • The hair is broken into 2 parts - the Root is the part of the hair located below the surface of the skin - the Shaft is the portion of the hair that projects above the skin
Structure of the Root • The Root is broken into 5 parts: 1-Follicule 2-Bulb 3- Dermal Papilla 4-Arrector Pili 5-Sebaceous Glands
Follicle • The tube-like depression or pocket in the skin or scalp that contains the root. • It extends downward through the epidermis (outer layer of the skin) into the dermis ( the inner layer of the skin)
Hair Bulb • The lowest area or part of the hair strand. It is the thickened, club-shaped structure that forms the hair root. The lower part of the hair blub fits over and covers the dermal papilla.
Dermal Papilla • A small cone-shaped elevation located at the base of the hair follicle that fits into the hair bulb. The dermal papilla contains the blood and nerve supply that provides the nutrients needed for hair growth.
Arrector Pili • A minute, involuntary muscle fiber in the skin inserted in the base of the hair follicle. Fear or cold causes it to contract, which makes the hair stand up straight resulting in “goose bumps”.
Sebaceous Gland • The oil glands of the skin, connected to the hair follicles. The sebaceous glands secrete an oily substance called sebum, which lubricates the hair and skin.
Structure of the Shaft • The Shaft is broken into 3 parts: -Cuticle - Cortex -Medulla
Cuticle • The outermost layer of the hair • It consist of scale like cells that over lap like shingles on a roof. • A healthy cuticle layer protects the hair from penetration and prevents damage to hair fibers
Cortex • The middle layer of the hair • About 90% of the strength of the hair comes from the cortex • Hair elasticity and color structure is located in within the cortex. • Hair-coloring, wet-styling, thermal styling, permanent waving, and chemical hair relaxing all take place in the cortex.
Medulla • The inner most layer of the hair • It is quite common for very fine and naturally blonde hair to entirely lack a medulla • Generally only thick course hair contains a medulla
Chemical Structure of Hair“The Proteins” • Hair is composed of proteins that grow from cells originating within the hair follicle • Hair is approximately 91% protein
Amino Acids • Amino Acids are the units of structure in protein • They are linked together end to end
Peptide Bond • The bond that that joins amino acids to each other is called a peptide bond • A long chain of amino acids linked together by peptide bonds is called a polypeptide chain
Chemical Structure of Hair“The Bonds” • The Cortex, middle layer of hair , is made up of millions of polypeptide chains • Polypeptide chains are crossed-linked together by 3 different types of side bonds; hydrogen bonds, salt bonds, and disulfide bonds • These side bonds hold the hair fibers together and account for the incredible strength and elasticity of human hair
Hydrogen Bond • Physical side bond that is easily broken by water or heat • Although individual hydrogen bonds are very weak, there are so many of them that they account for about 1/3 of the hairs overall strength
Salt Bond • Also physical side bond, but is broken by changes in pH • Salt bonds are easily broken by strong alkaline or acidic solutions and also account for 1/3 of the hairs overall strength
Disulfide Bond • A chemical side bond that differs greatly from physical hydrogen or salt bonds • Disulfide bonds join sulfur atoms of two neighboring cysteine amino acids to create cystine • There are far fewer than the physical bonds, but they are stronger and account for another 1/3 of the hairs overall strength
Hair PigmentMelanin • All natural hair color is the result of the pigment located within the cortex • Melanin is the tiny grains of pigment in the cortex that give natural color to the hair • Two different types of melanin are eumelanin and pheomelanin
Eumelanin • Provides brown and black color to hair
Pheomelanin • Provides natural hair colors from red and ginger to yellow/blonde tones
Haircolor vs Hair Color • Hair Color refers to the color of hair created by nature • Haircolor is the term used in the industry to refer to artificial haircoloring products • Natural Haircolor is the ratio of eumelanin to pheomelanin along with the total number and size of pigment granules • Grey Hair is caused by the absence of melanin
Hair AnalysisWave Pattern and Tendencies • Hair texture is the thickness or diameter of the individual hair strand • Hair texture can be classified as course, medium and fine
Hair Texture • Course hair texture has the largest diameter and has a stronger structure • Medium hair texture is the most common and is the standard to which other hair is compared • Fine hair has the smallest diameter and is more fragile and easier to process
Hair Density • Measures the number of individual hair strands on 1 square inch of the scalp. The average is 2200 hair per square inch and 100,000 total • Low density = thin hair • Medium density = Average or normal numbers of hairs per square inch • High density = thick hair or a high numbers per square inch
Hair Porosity • Porosity is the ability of the hair to absorb moisture • Hair with low porosity is considered resistant hair it requires more alkaline solution to raise the cuticle for processing • Hair with average porosity is considered normal hair
Types of Porosity • Resistant- cuticle lays close to hair shaft; absorbs slowly and requires longer processing time
Good Porosity • Cuticle slightly raised from shaft and absorbs moisture and/or chemicals in average time • Normal Hair that can absorb moisture in average time
Overly Porous Hair • Overly porous is often the result of over processing • Hair is damaged, dry, fragile, and brittle • Chemical services require less alkaline solutions with a lower pH to prevent additional over processing
Damaged, Over processed Hair • Hair is Dry, Brittle and Fragile • Until damaged hair is cut do not perm
Extreme Porosity • Use a lower Ph solution • Proceed with Caution
Elasticity • The ability of hair to stretch and return to its original length without breaking • Normal Elasticity in hair will stretch up to 50% of its original length when wet • Low Elasticity is hair that is brittle and breaks easily; will not hold a curl and is the result of weak side bonds
Growth Patterns • Hair Stream is hair flowing in the same direction; result of follicles sloping in the same direction. Two stream flowing in opposite directions create a natural part • Whorl is hair that forms a circular pattern as on the crown • Cowlick is a tuft of hair that stands straight up
Dry Hair and Scalp • Dry hair in scalp is caused by inactive sebaceous gland and is aggravated by dry winter or desert climate • The lack of natural oils leads to a flaky scalp and hair appears dull, dry and lifeless
Oily Hair and Scalp • Caused by overactive sebaceous gland and characterized by greasy buildup on the scalp and an oily coating on the hair
Hair GrowthTypes of Hair • There are 2 main types of hair found on the body; Vellus (or Lanugo) and Terminal hair • Vellus is short, fine, downy, unpigmented hair covering most of the body except palms and soles of the feet • Terminal hair is long, think pigmented hair found on the scalp, legs, arms and bodies of males and females
3 Growth Cycles of Hair • Anagen is the growing phase • Average growth is about 2 inches per month • 90% of hair is growing at one time • Grows for a period of from two to six years • Hair grows faster on women than men • Grows faster between ages of 15-30 and slows sharply after age 50
Catagen • Transition phase, ends the growth phase and last only one to two weeks • Follicle canal shrinks and detaches from the dermal papilla • Hair bulb disappears and the shrunken root end forms a rounded club
Telogen • Resting phase • Follicle begins a 3 to 6 month phase of resting • About 10% of hair is in Telogen phase at one time • The cycle then begins again, growth cycle repeats itself every 4 to 5 years
6 Hair Growth Myths • Myth #1 question • Clipping, shaving, trimming, and cutting makes hair grow faster ?
Fact • They have no effect on hair growth
Myth #2 • Scalp massage increases hair growth
Fact • No evidence to indicate this is true. Minoxidil and Finasteride are the only treatments that have been proven to increase hair growth and are approved for that purpose by the FDA
Myth #3 • Grey hair is coarser and more resistant than pigmented hair?
Fact • Other than lack of pigment, grey hair is exactly the same as pigmented hair. It is not resistant because it is gray, and is not more resistant than pigmented hair on the same persons head
Myth #4 • Amount of natural curl is determined by racial background?
Fact • Anyone of any race can have straight or extremely curly hair