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Not possible. The implants are soft sacks of some liquid, either a silcon based viscous fluid or a saline water solution. Liquids do not expand like a balloon would at the lower air pressure in an airplane. The implants do not get any bigger at all, let alone explode.
There are reports of women having reactions to silicon implants especially if they leak, and there was a (long discontinued) type with a foam plastic outer cover that caused problems: whether anyone died from implants, I don't know.
They might be lifesavers though:
An Israeli woman was injured in a rocket attack and surgeons found shrapnel in the implant that may have gone through her heart and killed her if not for them.
A Bulgarian woman was supposedly saved by her implants, she was in a car crash and her (very large) implants apparently absorbed the impact (and burst, but...) which could have been fatal for a "normal" person.