The Germany playmaker scored his first club goal since the start of December in the 4-1 FA Cup quarter-final win over Everton at the Emirates Stadium, where he also helped set up a fine finish for Olivier Giroud late on.
Arsenal's record £42.5million signing was taken out of the frontline by Wenger and given some extra time away to recover full fitness after a dead leg followed on from the first tie against Bayern, when Ozil's early fluffed spot-kick proved a turning point as the Bundesliga side won 2-0 after Gunners goalkeeper Wojciech Szczesny was sent off.
Wenger feels the 25-year-old former Real Madrid star is now fully focused once more as he prepares to head out to the Allianz Arena for Wednesday night's second leg clash.
"I think it affected him mentally too much, the penalty he missed against Bayern. It was not only physical, it was mental," said Wenger.
"He had the feeling he let the team down at a very important moment of the game, that affected his performance very much.
"Psychologically sometimes the wound is like a physical one. You can talk and talk and talk, but it takes time. You just have to leave it to time.
"I think he is over it. He has a good opportunity to show on Tuesday night how good he is."
Ozil was swamped by his team-mates after he dispatched a pass from Santi Cazorla low into the far corner to set Arsenal on their way after seven minutes on Saturday.
"It was certainly important to him, and to the team as well. I like the way he finished against Everton, calm in a convincing way," Wenger added.
"He made great runs and was absolutely outstanding from the first to the last minute."
Wenger hopes Ozil can go on to add a cutting edge to his game in the final third, having created more chances than any other Arsenal player against Everton.
"I would like him to find the right balance between being a provider and finisher," the Arsenal boss said.
"At the moment the balance is a bit detrimental to the finishing.
"His strong side is providing, but he is pacey, much quicker than people think he is, and with that technical quality and that pace, if he gets into the right areas and with the service he has, he can score goals."
During the international break, Ozil was jeered by some German supporters as he came off in the win over Chile in Stuttgart.
Wenger does not feel it is long before Ozil will have everyone back onside.
He said: "Ozil is hugely respected in Germany, but we live in a society where the period of time is very short between the boos to the applause. We have to live with that."