Plastination is a process used to preserve bodies or body parts by replacing all the water and fat tissue with curable polymers. The technique was first developed in 1977 by Gunther von Hagens. Hagens went on to create Body Worlds, the original exhibit of plastinated, cross-sectioned human bodies, with the goal of educating the public about the human body and its functions. A steady hand and patience, along with a meticulous attention to detail, are at the foundation of how Body Worlds exhibits are made.
In a Body Worlds exhibit, on display are full-sized plastinated bodies, various organs, and various cross-sections of human bodies. Many of the bodies are skinned, though the skinning happens after the individual has died. As creepy and morbid as they appear, there is no denying the positive impact these bodies – in all their plastinated glory – have had on the medical field.
Bodies Used In Exhibits Are Either Donated Or Unclaimed
Plastination inventor and the mastermind behind the Body Worlds exhibits, Dr. Gunther von Hagens, has assured the public that every human body on display has been sent to them by fully informed donors. In the past, von Hagens took cadavers from the former Soviet Union, but, after a body-trafficking scandal erupted, he broke off those ties. However, although he can produce the proper paperwork and forms for all of his bodies, none of those forms can be attached to specific bodies in the exhibits because they are made anonymous to protect their privacy.
The same can’t be said about his competitor, "BODIES... The Exhibition." Spokesman Roy Glover, openly stated that BODIES... The Exhibition acquires its bodies from China. They are all unclaimed and include executed political prisoners.
Plastination Allows The General Public To Become More Body Literate
Plastination is currently being used at medical and dental schools all over the world. It gives students hands-on experience without having to kill animals or expose themselves to harsh chemicals like formalin.
Exhibits like Body Worlds have also changed health education for the public. Plastination allows the comparison of healthy organs to diseased ones and they demystify the functions of the human body in general. At a Body Worlds exhibit, for example, a visitor can expect to see cross sections of healthy and unhealthy organs paired against one another as well as undelivered fetuses and their mothers who might've died in childbirth.
The Fixation Process Stops Decomposition
The first step in plastination is fixation. It involves careful dissection and embalming of the body, using a formaldehyde-based solution to halt decomposition. The process of preparing a body for a particular exhibit can be extremely time consuming, so it's important to stop the body from decomposing as quickly as possible. It’s during this step that the desired anatomical elements are prepared for display, and the body can be shaped during this step if needed. For example, if an exhibit is going to focusing on the body's ability to jump, one leg might be bent at the knee while the other is outstretched with its toe pointed in order to illustrate this function. More complex positionings (assembling the body into its final display position) happen later in the process.
The Specimen Goes Through A Dehydration Process
Long gone are the days of needing to let a body sit in the heat stuffed full of linen and herbs to dry out. An acetone bath can speed the dehydration process in a step known as "forced impregnation." When under freezing conditions, the acetone works to pull out all the water in the body cavity and replaces it. At the end of this process, acetone has taken the place of water in the body's cells.
Plastic Fills The Body In A Vacuum
The third step in the plastination process is yet another bath; this time, however, the body is placed in a bath of liquid polymer (basically a liquid plastic) inside a vacuum chamber. This can be made up of silicone rubber, polyester, or even epoxy resin.
This creepy body vacuum works by causing the acetone to boil at a low temperature. This vaporizes the acetone, turning it into a gas that needs to escape the body's cells. Then, as it’s pulling out of the body’s cells, it’s also drawing the liquid polymer in at the same time. This gives you liquid-plastic filled cells.
Positioning Is Done Before Hardening And Can Last For Months
Once the specimen has been preserved and filled with plastic, it’s then bent and pinned into what will be its final position. Obviously there is some stiffness and awkwardness involved in this – the body is filled with plastic now – but, with the use of ropes, wires, clamps, foam pads, and needles, the perfect positioning can be accomplished. Each muscle, nerve, and vessel is strategically placed into the desired position before being allowed to fully harden.
The Curing Process Seals The Deal
Once everything is where it belongs, the polymer chains inside the cells (which are still fairly liquid) need to be hardened to make it permanent. Like with any dried and preserved meat, there’s a curing process required for this to happen. The body can be cured with ultraviolet light, gas, and heat. It's sort of like sitting under the UV light to get your pedicure to set, except not at all.
Variations In The Process Allow For Customization
There are modifications that can be made to the plastination process, and each method has its own benefits depending on the style you’re attempting to achieve with a particular body. The most common method is the "Silicone S 10," which creates an opaque and overall natural look.
The "Cor-Tech Room Temperature" procedure is designed to allow various degrees of flexibility by using three combinations of polymer, crosslinker, and catalyst.
To display organ slices or anything thin and transparent, the "Epoxy E 12" procedure is recommended, but using the "Polyster P 35 (P 40)" method is ideal for preserving firm, semitransparent brain slices. It really just depends on what you're in the market for.