Implant Casting and Implant Finishing: Difference between pages

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'''Implant casting''' is one way to avoid the rough surface left by carving [[Silicone|silicone]] and other polymers. Casting silicone is similar to casting any other polymer and involves (put simply) mixing a liquid base with a secondary agent that hardens that base, and pouring it into a mold (usually coated with a release agent so it does not stick — make sure you use a release that is designed for medical [[Category:Implants|implants]]). Most involve a 10:1 two-part mixture that can be cured at room temperature, although many variations exist (numerous websites describe the process in detail).
'Postoperative studies have shown that the surface of an [[Category:Implants|implant]] plays a large role in the development of complications. If an implant is smoothly finished and fits the surrounding tissue like a glove, it naturally has far less negative impact. If, on the other hand, the implant has been carved and has "chiseled" edges, these seemingly minor points can, and will, irritate the surrounding tissue, leading to continued flare-ups and difficulties.


Pourable silicone for casting are available in a wide variety of [[Durometer|durometers]] and should be obtained in grades specifically intended for '''long term implant applications''' (i.e., biocompatible — "implant grade" or "medical grade," not "healthcare grade," which is only suitable for external use such as special effects).
While it is true that the body is pretty good at encapsulating these irritations with scar tissue (and many people could have a very rough implant inserted and never know the difference), why force your body to work extra hard to [[Wound_Healing|heal]] when all it takes is a little more effort in the manufacturing step?


High-grade plastics are readily available to the public — in theory, anyone could just buy them and manufacture custom implants by pouring the plastic into cookie-cutter shapes in their kitchen. However, to avoid voids (bubbles) in the implant, a degasser or vacuum chamber (available in the $200-$300 range, although some people have experimented with $30 dessicators and other low-tech solutions as well) should be used, although it should be noted that, with some low viscosity plastics, these are not needed. Other options include technologies such as injection molding, but these tend to be outside of the price range of most non-medical implant artists. In addition, medical casting should be done in a clean environment (clean as in clean-room, not clean as in ''Mr. Clean'') to avoid introducing surface contamination (i.e., if it's in the air, it's in the implant).
Additionally, if the implant is made using a porous material such as [[Teflon]], an improper finish can result in tissue actually growing into the implant — while this does keep your implant from shifting under the skin and techniques like this are commonly used by plastic surgeons, it also makes it virtually impossible to remove in the long-term without far more work.


In more detail, a typical procedure would involve the following steps (assuming that a mold has already been prepared properly and sprayed with a medical-use release agent). Please note that this is a generalization, and you should follow the manufacturer's directions, not these!
As a customer, you can minimize this risk by visually inspecting the implant. Is its surface smooth on all sides? Can you see any marks from machining (such as grooves)? Does it appear to have been roughly carved, or are the edges smooth and uniform? Does the implant's shape appear to fit your body precisely?


# Mix the silicone and catalyst, in precisely the required ratio. Stir vigorously for about five minutes.
[[File:Implant_Finishing-1.jpg|thumb|center|358px]]
# Degas the silicone if required (i.e., get the bubbles out of it). This will probably take about ten minutes.
# Pour the silicone into the mold and put that back into the vacuum chamber for secondary degassing (with some designs of chamber you may be able to do this all inside the chamber). This will probably take about 45 minutes. Hardening usually takes between one and two hours from the initial mixing.
# Depending on the silicone being used, you may have to add heat to finish the cure, although most will cure at room temperature — just not as quickly.


The resultant implant can be carved additionally if need be, and can be sterilized in an autoclave without damaging it in any way. There are multitudes of silicone suppliers (just type "silicone casting" into Google) which sell the raw materials, as well as the tools required to shape them (although they can often be found on eBay for less).
== Entries related to this risk ==
 
* [[Category:Implants]]
Note: There are a very limited number of implant silicone manufacturers as a result of the liabilities involved, and many suppliers for these companies will not sell the materials to the general public.  Manufacturing a truly "clean" silicone implant is an exceptionally expensive and involved process.
* [[Genital Beading]]
* [[Implant Casting]]'

Latest revision as of 05:43, 17 September 2023

'Postoperative studies have shown that the surface of an plays a large role in the development of complications. If an implant is smoothly finished and fits the surrounding tissue like a glove, it naturally has far less negative impact. If, on the other hand, the implant has been carved and has "chiseled" edges, these seemingly minor points can, and will, irritate the surrounding tissue, leading to continued flare-ups and difficulties.

While it is true that the body is pretty good at encapsulating these irritations with scar tissue (and many people could have a very rough implant inserted and never know the difference), why force your body to work extra hard to heal when all it takes is a little more effort in the manufacturing step?

Additionally, if the implant is made using a porous material such as Teflon, an improper finish can result in tissue actually growing into the implant — while this does keep your implant from shifting under the skin and techniques like this are commonly used by plastic surgeons, it also makes it virtually impossible to remove in the long-term without far more work.

As a customer, you can minimize this risk by visually inspecting the implant. Is its surface smooth on all sides? Can you see any marks from machining (such as grooves)? Does it appear to have been roughly carved, or are the edges smooth and uniform? Does the implant's shape appear to fit your body precisely?

Implant Finishing-1.jpg

Entries related to this risk

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