If the nail is black, you will lose it. The best drill is to make a hole
in the
fingernail immediately after the injury. This is best done by heating a needle and touching it to the nail until blood comes out. Sounds yucky and painful but it is actually painless. There are no pain sensors in the nail and you stop when you hit blood, which is under pressure and immediately comes out. The drill is NO HEAT for 24-48 hours, then warmth. Heat causes swelling, which is the last thing you want to do.