Hi! everyone,

let me clear some aspects of the above topic. Silicones
are widely used medically. In the field of plastic surgery
(cosmetic or aesthetic or esthetic surgery), they are used
as:
1. breast implant
2. facial implants (chin, nasal etc.)
3. Fillers (injected straight under the skin to modify the
contour)
4. Scar treatment (compression sheets applied straight
onto scars to
prevent and/or treat hypertrophic scars & keloids)
5. Components of 'artificial skin' (forms a backing, top
layer, which is
removed later on)

Before going further, let's define some terms:

Silicon:
Silicon (Si) is a metal in the same column as carbon in
the periodic table. It is the most abundant element on
earth and does not occur naturally in its pure metallic
state.

Silica:
Silica (SiO2) in its crystalline form is common sand or
quartz.

Silicate:
Negatively charged (anionic) form of silica eg. [Si2O7]6
¡Ý or other compunds of Silicon eg. fluorosilicate
(SiF6)2-. In one form it attracts water molecules
(hydroscopic) so it is placed in containers of dried food
as a small, white packet labelled 'do not eat' to keep
them dry.

Silicone: (R2SiO)n, where R=organic groups such as methyl,
ethyl, and phenyl.The class of substances known as
silicones are polymers of silicon and oxygen. There are as
many forms of silicone. Dimethylsiloxane=(C2H6OSi)n where
n is typically >4, is the building block for most
medical-grade silicone products, including breast
implants. It can be made extremely pure and modified into
products with a multitude of characteristics (various
viscosities to hardness).

Why use silicone?
Because it is easier for the surgeon. They come in
ready-made sizes, shapes & textures so it is easy & quick
to apply or insert.

What are the problems?
It is a common rumor that silicone is associated with
certain illnesses, including breast cancer and connective
tissue disorders (also referred to as autoimmune diseases
such as lupus, scleroderma, and rheumatoid arthritis).

Large scientific trials have disproved such rumors:
1. Eherenfeld M., Shoenfeld Y, Bar-Meir E. Silicone gel
breast implants and connective tissue disease--a
comprehensive review. Autoimmunity, June 2003, vol.36
no.4, pp.193-197(5)

2.
http://www.lookingyourbest.com/info/breastimplant-swhatis.php

However, there are a group of few, unfortunate individuals
who display some kind of unfavourable results. The causes
could be divided into 3 groups:

1. The surgeon: (Not skilled enough or human error during
placement)
-assymetry
-protrusion
-hematoma, Infection, skin necrosis etc.

2.The material: (modern versions of silicone are tough,
well textured,
shaped & easily integrates with surrounding tissue.
-rupture (when they rupture, the fluid/viscose
silicone escapes the
firm capsule into the surrounding tissue & may
calcify & become
as hard as a rock)
-migration (moves around) etc.

3. The individual
-Chronic inflammatory reactions which leads to
'capsular contracture', displacement of the implant to
nearby structure or protrusion through the skin. Not only
this but it may be associated with other symptoms such as
pain, irritation etc. The individual tends to blame all
other medical problems, at that time to the silicone (I
think it is a kind physical & psychological rejection of
the foreign substance).
Individuals who suffer from such problems are really
shocked & makes alot of 'noise', such as this website:
http://www.siliconeholocaust.org/

If there are no 'rejection' then the silicone implant may
last/stay 20 or more years, some say a life time. But it
is hard to predict which patient will undergo 'rejection'
& which will not.

Autologus tissue can be used to replaced all such
procedures done using silicone implants, however the
problems are:

1. Time consuming (takes too long & may be tiresome to
harvest the tissue eg. when using autologus abdominal fat
& skin as a 'flap' to reconstruct the breast, it takes
about 6-7 hours for 1 breast). 'Flaps' are units of
tissues supplied by one neuro-vascular system.

2. Donor site morbidity (pain, scar, loss of muscle
function etc.)

3. General anaesthetic problems (most silicone implants
are inserted with mild sedation & local anaesthesia in the
form of 'tumescent' meaning diluted local anaesthesia to
increase the volume, while autologus tissues are harvested
using general anaestheisia in most cases especially breast
reconstruction).

For the time being the use of silicone is increasing
especially in the developed world. One may think why such
procedures or are they necessary? Well, it is, to improve
the QOL (quality of life) of patients who have been cured
of life threatening illnesses eg. cancer by the progress
in modern medicine & who have been made to live longer but
with defects. Such people do not only want to live longer
but live with normal looks & functions.

Hope I've cleared some aspects.

William




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