My boy friend is a diabetic and got his ingrown toenails removed?

He told me the doctor placed something in his toe, something that looked like the tip of a match stick and he said it looked like magnesium. She also cut a little bit of his skin. This was 3 days ago and his upper toe area looks a faint grayish color. Is that because it is bruised? has anyone else heard of what they put in to keep ingrowns from coming? Is it really magnesium?