Do your best to determine there's damage prior to pulling the head.
Although it's very likely, you don't want to pull the head if not
necessary. At the very least, you can install the timing belt and slap
the crank pulley on to hold it in place and then see if the engine starts
and runs normally.
If the valves are bent, have a look at the pistons and upper cylinder
walls to be sure there's no significant damage. Bent valves rarely
significantly damage the pistons. On the other hand, if one of the valves
broke, you'll see a pretty good sized mess when you pull the head.