hair growth help?

So, my baby boy has had a stubborn little nick smack dab in the middle of his face since I got him a year ago. (you can see it in my avatar)
Now, he's quite a slow hair grower, but i'm thinking in this case it's scar tissue that's preventing him from having a perfectly furry face. C:
I use MTG pretty religiously on his other nicks, and it works well-ish. So, have any products or hair growth stimulants or home-made miracles that work on scars? Or just ones stronger/more effective than MTG?

Thankee. C:

I'm pretty sure if it's scar tissue, the hair cells or whatever are gone, so no matter what you put on it, it will forever be a bald spot. =|

Aaaw I think it gives him character... my gelding Bishop has one too, and I've tried EVERYTHING but nothing worked, si I agree with the above post