there is no fix, replace the bumper cover. its stretched, it will never "unstretch" and retain its original form. the space between the molecules has been modified, they will never again group as they did from the injection molding machine
remove the bumper there is more damage underneath than you think it looks like you bent the support brackets also some bumpers have small metal brackets inside them if they are bent no heat will straighten them out pull off the bumper and look under/inside it you should be able to see what I am talking about
If the plastic is not damaged other than dented then softening it up with heat should relax the plastic and allow it to return to it's molded position. But you may have to help it move back, so be ready with something soft.
Hope this helps.
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i cant get those thing..can i pour a very hot water on it?..and then use my hand to shape it up
i bang into a metal handrail..this is the pic(pls open the link) http://tinypic.com/r/2430lrl/8..i saw some video on youtube using hair dryer or hot water to fix the dent?..will this 2 method work?..if not wats is ur solution..i wanna repair myself asap before my boss see:-(