It IS being worked on, but things move quite slow - and there doesn't seem to have been much progress for decades, but: Cure for hair-loss. Some might say it's just vanity, but if someone could come up with a cure, and sell it affordably, that would be a multi-billion, maybe even trillion dollar industry. Going from quite balding (NW4-NW7 in balding terminology) to a full head of hair makes most guys look a solid 10-…
Edit: Just searched up synthetic hair implants
The FDA banned the synthetic fibers in the US in 1983. The ban resulted because widespread use in the 1970s led to numerous complications including recurrent infections, rejection, contact dermatitis, granulomatous hypersensitivity reactions and cyst formation. Not to mention frequent loss of fibers from breakage.
The synthetic fibers continue to be manufactured in Europe where they are still in use.
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