Polypropylene breast implants, also known as string breast implants, are a form of breast implant using polypropylene

Polypropylene

Polypropylene , also known as polypropene, is a thermoplastic polymer used in a wide variety of applications including packaging, textiles , stationery, plastic parts and reusable containers of various types, laboratory equipment, loudspeakers, automotive components, and polymer banknotes...

 developed by Dr. Gerald W. Johnson. Due to a number of medical complications

Complication (medicine)

Complication, in medicine, is an unfavorable evolution of a disease, a health condition or a medical treatment. The disease can become worse in its severity or show a higher number of signs, symptoms or new pathological changes, become widespread throughout the body or affect other organ systems. A...

, the device has been banned in the European Union

European Union

The European Union is an economic and political union of 27 independent member states which are located primarily in Europe. The EU traces its origins from the European Coal and Steel Community and the European Economic Community , formed by six countries in 1958...

 and United States

United States

The United States of America is a federal constitutional republic comprising fifty states and a federal district...

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Polypropylene implants absorb water very slowly, about <0.01% in 24 hours. The polypropylene, which is yarn-like, causes irritation to the implant pocket which causes the production of serum

Serous fluid

In physiology, the term serous fluid is used for various bodily fluids that are typically pale yellow and transparent, and of a benign nature, that fill the inside of body cavities. Serous fluid originates from serous glands, with secretions enriched with proteins and water. Serous fluid may also...

 which fills the implant pocket on a continual basis. This causes continuous expansion of the breast after surgery. Growth can only be alleviated by removal of serum by syringe. Problems can also arise if the breasts enlarge at different rates. This can be corrected by removal of serum or introduction of sterile saline. Continual breast growth will eventually result in "extreme, almost cartoonish breast sizes."

String implants were only available for a very short time before being removed from the market by the FDA around 2001.

Polypropylene implants have created the largest recorded increases in breast size due to surgical augmentation

Surgery

Surgery is an ancient medical specialty that uses operative manual and instrumental techniques on a patient to investigate and/or treat a pathological condition such as disease or injury, or to help improve bodily function or appearance.An act of performing surgery may be called a surgical...

. They are rarely seen outside the adult entertainment industry. Big-bust entertainers Chelsea Charms

Chelsea Charms

Chelsea Charms is the stage name of an American big-bust model, internet model, and stripper. Artist Marc Quinn created a life-sized sculpture of Charms, which the The Guardian described as "virtually all bosom".-Biography:...

, Maxi Mounds

Maxi Mounds

Maxi Mounds is an American nude big-bust model, stripper and occasional pornographic actress originally from the Long Island, New York area. Ms. Mounds is known for her extremely large breast implants. Mounds' implants are polypropylene string breast implants, which irritate the breast tissue,...

, Kayla Kleevage

Kayla Kleevage

Kayla Kleevage is a big-busted stripper and pornographic actress in the big-bust genre.Kayla has had her website since 1996 and also runs her own video company, Kleevco Productions. Kleevco has produced a three-volume series called Hot Chocolate...

 and Minka are some of the best known recipients of polypropylene breast implants.
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