What do you mean 'hole'...didn't they close it up with the stiches...or pack it? If there is a significant hole you could have a problem...wounds need to heal from the inside out and a hole may not allow this to happen.
As for scarring, you can use any good oil and massage it frequently once it's healed. Some say vit E oil is best, but I've read studies that refute that. The frequent massage will help break up the scar tissue and increase circulation to the area. I had a surgical scar that was discolored and ropey...now it's the same texture as the rest of my skin and a very faint white line...not even noticeable to others unless I point it out. All I did was massage it frequently with some oil or cream to lessen the skin friction.