Page 177 - Chapter 3 - Laser/IPL Hair Removal

Chapter 3 – Fundamentals of Laser/IPL Hair Removal 2nd Edition
Alexandrite:
Threshold – 9.4 J/cm2
1.0
63.2
10.4 J/cm2
7.3
99.9
11.4 J/cm2
51.1
100
Table 34 – Final values of Omega when increased fluences are applied
These data reveal something very interesting, and not intuitive! A small increase in applied fluence can make a huge difference in the value of Omega, from a 63.2% damaged level to nearly 100%.
Interestingly, increasing the fluence by only 1 or 2J/cm2, has significantly different effects across the devices. The Alexandrite laser induces a much greater change in Omega than an Nd:YAG laser, with diode lasers/IPLs coming in between these two, because of its greater absorption coefficient in melanin.
Our recommended starting fluences for different body sites
We recommend using the following set of fluences, as a starting point:
Device:
Table 35 – Recommended fluences for four devices
In Table 35 we show our recommended minimum fluences for various body areas and for the four main hair removal systems, as starting points for superficial hair follicles. You may notice that these are all just the threshold fluences plus 1 J/cm2 (approx.), except for the Nd:YAG fluences, where we have added 2 J/cm2. We suggest these fluences to ensure a denatured volume of at least 99% of the stem cells, which should always generate good results.
It must be remembered that these are ‘general’ fluence suggestions – in many cases you will require more fluence to reach deeper follicle stem cells in the bulb region, depending on the body site (See ‘Threshold Fluences for Full Follicle Depths’). If insufficient fluence is applied, some of the deeper stem cells may survive, allowing a finer, thinner hair to grow back in the next anagen phase.
Thin hair is usually a sign that insufficient fluence was used in a previous treatment (See the
section ‘Why do ‘finer’ and ‘lighter’ hairs appear after laser/IPL hair removal treatments?’).
________________________________________________________________________ 177 Chapter 3, Ed. 2.0 Laser/IPL Hair Removal
© The Laser-IPL Guys, 2025
Upper lip
Chin/arms
Arm pits/legs
Bikini
Fluence
J/cm2
J/cm2
J/cm2
J/cm2
IPL
12.5
22
25
29
Diode
12
21.5
24.5
28.5
Nd:YAG
26.5
46.5
53
62
Alexandrite
10.5
18
20
23.5