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Why is a series of
treatments required?
Everyone's hair grows
differently, depending
on age, weight,
metabolism, hormones,
ethnicity, medications
and other factors. But
all hair goes through
three distinct growth
phases:
Active growth
phase (called the anagen
phase), which
lasts between 2 and 7
years. During this phase
the dermal papilla
actively produces cells
which form the hairshaft.
In certain areas of the
body, such as the scalp,
the majority (83%) of
the hairs are in this
phase. During the anagen
phase the hair has an
abundance of melanin.
Degradation
phase (catagen phase),
which lasts between 10
and 20 days, during
which the hair stops
growing but is not yet
shed. About 3-4% of our
body hair is in this
phase at any given time.
The hair follicle
shrinks at this time as
the hair is prepared for
eviction.
Resting phase (telogen
phase), which
can last for several
months, during which the
hair falls out and a new
hair begins to form. The
hair follicle is not
treatable during this
time.
Laser
treatment is only
effective when the hair
is in the active growth
phase. Hairs or hair
follicles in the
Degradation or Resting
phase need to progress
to the active phase
before treatment will be
beneficial. Therefore,
multiple treatments are
required for long term,
permanent hair
reduction.
Also,
in a single treatment,
not all of the hair
follicles in the active
phase will be destroyed.
Some follicles are
destroyed, others may be
miniaturised into vellus
hairs (light, fine
hairs), and some enter
prolonged dormancy. The
initial treatment should
be repeated to take care
of active hair follicles
that were not
effectively treated in
the first session as new
hair growth is observed,
this will typically be
some 2 to 4 weeks later
depending on where the
treatment area is.
Further treatments
should be planned at
regular intervals to
clear hairs that are
coming out of the
resting phase and into
the active growth phase.
Given the number of hair
follicles in the resting
phase at any given time,
this new hair re-growth
can be significant.
Any
follicles without a
target hair within will
simply grow again and
can be treated next time
round. |
