Depend on what kind of damage it has done. If it has caused a short, damage may be done. If it is just a scratch breaking a trace, no damage will be done. It also depend on the location of the damage. For example, if it has caused a short on one of the power supply traces, there is a possibility that it may fry your psu. If it has disconnected a CPU trace, you may not be able to use 1 RAM slot or one PCI lane might be missing.