Can you whiten bonded teeth to the original color of the resin used?

My son had part of his front two teeth knocked out a few years ago and repaired by bonding. Last week at work a box fell off the truck at work and hit him in the mouth. One of those teeth is chipped and needs to be repaired again, but they are also more discolored now. Don't really want to match the new bond to the current color. Wondering if you can at least bleach the bonded teeth to the original color of the bonding when they were done? Will surface stains be removed?