Experts opinion needed!!

[Hany Saad]

Hello all,

I am going tomorrow to the dealer to change the door hinge and the brakes caliper under warranty as it was squealing a week ago whenever I reach full stop .To my surprise the brakes stops squealing since yesterday all by itself ,I am trying to hear the squealing sound but with no success,I do not know what should I do?should I tell the dealer about it and change the brakes caliber anyway or just leave it as it is,as it is working perfectly since yesterday without doing it even once.
does any one know what causes the squealing at first and why it was gone by itself?is there any relation between heat and squealing sound as I felt whenever I drive in crowded roads for long times the squealing starts to appear.

any help will highly appreciated.