The striker had loan spells with Sheffield Wednesday and Leeds United in the Championship this season, before being recalled from the latter last week.
Oatway has said that he is pleased that the 21-year-old was keen to leave the club in search of first-team football.
"What I liked about him is that he wasn't in the squad a couple of times and he went and asked if he could go out on loan," Oatway told the Sunderland Echo.
"I don't know if it's rare for players to ask to go out on loan these days, but it isn't as common as it used to be. So you're hoping that all of these little bits add fuel to his fire, hopefully give him a little bit more education about football and life, and hold him in good stead.
"That's why we brought him back and he walked straight back onto the training pitch, and at Anfield, and gave a good account of himself."
Wickham has scored four goals in 43 appearances for the Black Cats.