The different types of hair to be treated will affect the choice of modality, current intensity and timing of treatment.
Darker and thicker hairs will require a higher current intensity than finer, less dense hairs. Curved hairs are due to distorted hair follicles and so the blend method will be more successful.
LANUGO HAIR
- Fine, soft, without a medulla and un-pigmented
- Found in foetal life and is shed around the 7th or 8th month of pregnancy
VELLUS HAIR
- Fine, soft, downy and un-pigmented
- Generally found all over the body
- Rarely exceeds 2cm in length
- Does not have a medulla
- Its base lies close to the skin surface
TERMINAL HAIR
Terminal hair can be divided into three groups:
- Asexual hair: present at birth, influenced by growth hormones and is found on the scalp, eyebrows, eyelashes and, to a lesser extent, on forearms and legs, in both sexes and at all ages.
- Ambisexual hair: develops in both sexes at puberty, influenced by steroid hormone production and is found in the axilla, pubis, lower limbs and abdomen. Density and rate of growth varies widely between sexes and within individuals of the same sex.
- Sexual hair: influenced by androgen hormone production. Different areas will have different levels of sensitivity to androgens; for example, the pubic area and armpits are particularly sensitive and will develop axillary hair. Pubic and axillary hair will develop on both men and women, although males will develop more pronounced terminal hair and in more areas – nasal passage, ears, beard, upper lip, back and chest – as they have naturally higher levels of testosterone, the male hormone. This type of hair is longer, coarser and pigmented, varies in shape, diameter, texture, length and colour.
INGROWN HAIRS
Ingrown hairs can be recognised by appearance of bumps on the skin, irritation and erythema – the hair is sometimes visible under the skin. They are thought to be caused by friction, irritation and dry skin and can be treated by using a sterile needle to release the hair from under the skin. If the skin is inflamed and infected, the hair should be left ‘in situ’ until the skin is healed, before treating with electrolysis; this ensures the hair’s ingrown pathway is healed, preventing it from growing back.
‘TOMBSTONE’ HAIRS
These are small hairs from a follicle previously treated in the anagen stage of growth, but which remain in the skin as the electrologist will have removed a hair from the follicle when in the telogen stage, unaware that a new anagen hair was forming underneath.
These hairs are thick, very dark, brittle and look like a ‘foreign body’ at the surface of the skin. They do not need to be treated; they can be removed simply through cleansing and exfoliating the skin, or tweezing.
COMPOUND HAIRS
These are also known as ‘Pili Multigemini’ hairs and occur where the follicle has two or more dermal papilla, which results in two or more hairs growing from the same follicle. To treat, identify the most conspicuous hair and treat with the current – this may affect both hairs. Remove the first hair and then see if the second hair will remove without traction if not treat the second dermal papilla with slightly reduced intensity and time.
CURVED HAIRS
The growth cycle of a curved hair is the same as for a straight hair. Curved follicles can be found in Caucasian skin, but predominantly occur in Black skin. In most cases, the lower quarter of the curved follicle turns at an obtuse angle from the follicle, which causes a flattening of the hair structure. This flattened shape is what causes the curling of the hair shaft.
The curve of the hair above the skin can be greater than the follicle curvature; this is because the root encased in the root sheaths is in a newly formed, moist condition – the hair begins to curl once it has left the sheath and begins to dry. When the hair slides out, check the depth and use this as a guide for following insertions.
HAIR GROWTH CYCLE
Terminal hair is cyclical; it goes through three stages of growth and regeneration:
ANAGEN
This is the active growing stage. Hairs may remain in anagen for a few weeks or months, depending on the site. New cells are produced in the matrix of the hair and new hair receives nourishment (blood and oxygen supply) from the dermal papilla. New hair cells move upward to form the individual structures of the hair, including the follicle itself and the inner root sheath. The inner root sheath cuticle ‘downward facing cells’ interlock with the ‘upward facing cells’ of the hair cuticle, which anchors the hair into the follicle. When the cells reach the upper follicle they become keratinised.
Electrolysis is most effective at this stage. When an anagen hair is removed, the bulb and the inner root sheath are clearly visible.
CATAGEN
This is the transitional/changing phase, where the hair is changing from active to resting and lasts approximately 2-4 weeks, as the hair separates from the dermal papilla and the hair follicle shrinks back. A catagen hair does not have a visible bulb.
TELOGEN
This is the hair’s resting phase. The now shortened follicle rests until it is stimulated to grow again. A hair in telogen has very little nourishment, so will appear dry at the base end. The old hair is shed and new hair growth is generated.
