"We have lost van Persie, of course, so for Bendtner and Chamakh to score is very important," said the Frenchman after the game.
"It is very important that they have a level of confidence to be successful in the big games.
"You need your strikers to take any chances and Bendtner tonight did that well.
"We need Chamakh with the games in front of us," he added.
"He had a great start to the season until the end of the November, early December when he looked a little bit burned out.
"Now he looks back [to himself] because even in training he looked a little bit tired. It's good for him that he scored."
Wenger, though, warned Bendtner that his hat-trick against the Os does not guarantee him a starting berth at the Nou Camp against Barcelona next week, saying: "You know what, it puts him contention to play against Sunderland. And, frankly, for us that is a vital game."