image retention vs burn in

[Erman_94]

hi there...i have a samsung plasma that ive had for about 2 or 3 years and apart from movies/blu ray i also watch a lot of standard cable on it (i.e vertical bars on each side)

i havent had a problem with it before but i now noticed that during a movie, when the scene is "dark" or has a "black background" i can detect these faint gray vertical bars on the sides of my panel

is this permanent burn in or image retention?

i TRULY hope it is something i can get rid of.

for the past 2 days i have been using the zoom and pan&scan function on my cable box just to avoid the bars on the side but it doesnt seem to be working to remove it. would i need to be doing this longer to rid the screen of these faint bars?

thanks.