What Causes A Discharging Hole On The Cheek?

my son has a hole in his cheek.. just behind the skin of the wisdom teeth. On the right side is one large hole. On the left hand side are 3 smaller holes. There is something grayish white coming out of it. If I take a Q-tip I can pull some of it out. It resembles a bit like a brain. Mushy but comes out like a ball. Can you please tell me what you think?