Cosmetology - Trichology

Trichology

The technical term for the study of hair.

Medulla

Central core of the hair shaft (often absent in fine or very fine hair)

Cortex

Inside the second layer of the hair fiber; gives hair most of its pigments and strength (elasticity).

Cuticle

Outer covering of the hair shaft; the loose and pilible skin around the nail.

Anagen

Active or growing stage of hair, during which each hair bulb has an attached root sheath.

Telogen

Resting stage of hair growth when each bulb has no attached root shaft, at which time hair falls out; eventually, cell division is again stimulated, producing new hair, and thr growth cycle starts again.

Catagen

Brief transitional stage of hair growth when all cell division stops.

Eumelanin

Type of melanin that produces brown/black hair color.

Pheomelanin

Type of melanin that produces red hair color.

Melanocytes

Cells that exist among the dividing cells within the hair bulb.

Melanosomes

Bundles of melanocytes that rest near the hair bulb's nourishment center, the dermal papilla.

Trichoptilosis

Fragilitis crinium or brittle hair; technical name for split ends.

Fragilitis Cranium

Technical term for split ends, small cracks in the cuticle of the hair that deepen into the cortex.

Pilica polonica

Excessive matting of the hair, characterized by a mass of hair strands tangles together in a mat that cannot be seperated.

Nodules/Trichorrexis nodosa

Lumps or swelling along the hair shaft.

Canities

Grayness or whiteness of the hair.

Ringed hair

Alternating bands of gray and dark hair.

Hypertrichosis

Referred to as hirsuties or superfluous hair; the abnormal coverage of hair on areas of the body where normallu only lanugo hair appears.

Monilethrix

Beads or nodes formed on the hair shaft.

Psoriasis

Thick, crust patches of red irritated scalp resulting from an autoimmue disease of the skin.

Pityriasis Capitis

Dry dandruff; dry epithelial cells attached to the scalp or on the hair; itchy; caused by poor diet, uncleanliness or emotional disturbance.

Pityriasis Tinea

Infections of the skin or nails caused by fungi and appearing as itching circular patches

Pityriasis steatoides

Greasy or waxy dandruff; oily flakes combine with sebum (oil) and stick to the scalp in clusters and can appear yellowish in color.

Scabies

Itch mite; red and watery vesicles or pus-filled areas caused by an animal parasite burrowing under the skin.

Pediculosis Capitis

Head lice; infestation of head lice om the scalp causing itching and eventual infection.

Vellus

Hair that covers most of the body, including the head; often not visible to the naked eye.

Alopecia

Excessive hair loss

Androgenetic alopecia

Hair loss caused by the combination of heredity, hormones and age that causes progressive shrinking or minziturization of certain scalp follicles.

Postpartum alopecia

The temporary hair loss at the conclusion of pregnancy.

Alopecia areata

Sudden loss of hair in round or irregular patches without display of an inflammed scalp

Telogen effluvium

Premature shedding of hair in the resting ophase (telogen) resulting from various causes such as childbirth, shock, drug intake fever.

Traction

Hair loss due to repetitive traction on the hair by pulling or twisting