Braces and the overbitee?

ok i havee a bout a 1 cm overbitee its not THAT extreme and i have tah qet braces i already had em b4 but that was to striqhteen my teeth out (i have really bad teeth) and now i nneed a 2nd pair to fix the over bitee how lonq shud it takee and will i havee to qet like head qear or rubberbands or anythinq + mahh teeth aree also i little crooked but not that badly so howw lonqq???