I can't see what you are talking about, but if you have some dead areas with pure white skeleton showing, those won't grow back. The coral will regain it's color and grow elsewhere however. What caused the nitrates?
Did you sort it out?
If you get your parameters stable and keep them pristine, it can rebound. The monti in my tank survived a 3 day power outage with no water circulation besides be giving everything a stir with a wooden spoon before and after work...it looked like a pure white skeleton with white polyps. It took time, but it eventually came back. Address the nitrates and what caused them, the monti should flourish.