Both Manchester United and Chelsea notched up victories to close the gap at the top, but it could have been so much worse had it not been for the young Dane's late, late strike.
Arsenal had been looking to get back to winning ways following the numerous disappointments of their last game against a side from Birmingham.
With the absence of Eduardo da Silva, Wenger gave Theo Walcott a chance to play in his preferred position in attack.
It was Walcott who forced the first save out of Scott Carson six minutes in when he latched on to a ball into the right side of the penalty area and swiftly dispatched a shot across goal which the Villa keeper parried superbly.
Gabriel Agbonlahor caused the Gunners a worry on 13 minutes he sped away with the ball from just inside the Arsenal area.
The England Under-21 striker cut into the left side of the Arsenal area, but just as he pulled his leg back to shoot, William Gallas slid in to make a glorious saving tackle.
Philippe Senderos could have given the Gunners the lead when a half clearance by Carson fell to the Swiss defender, but he fired over the bar when he should have done better.
Senderos did score on 27 minutes but into his own net as Agbonlahor had again caused the Gunners problems with his direct running.
The young striker powered his way into the left side of the Arsenal area and delivered a hopeful ball across goal which Senderos tried to cut out but re-directed beyond Manuel Almunia.
Arsenal were not incisive enough for the remainder of the half as they looked to walk the ball into the net.
A typical example came in first half injury-time. Walcott broke well on the right flank and eventually got into the striker had no option but to pass back to Cesc Fabregas, whose woeful shot from inside the area sailed high over the bar.
The Gunners were quick off the blocks in the second half and Carson had to be at his sharpest within a minute of the restart when he parried Walcott's low drive from the right side of the area.
With both Manchester United and Chelsea cruising to victory in their respective games, Arsene Wenger sent on Bendtner just before the hour to bolster the attack.
Gael Clichy forced a save out of Carson on 64 minutes and a minute later Almunia had to save from Agbonlahor yet again.
Martin O'Neill signalled his own attacking intent by bringing on Marlon Harewood, who caused the Gunners even more problems with his pace and power.
Attack looked to be a good form of defence for Villa, while the quality of Arsenal's football fell far below what was required to breakdown a well organised defence.
Over-hit passes, mis-placed crosses and corners typified the fayre on offer as the Gunners looked like they had surrendered their lead at the top of the table.
Then, with just seconds remaining, Bendtner was in the right spot to guide home Emmanuel Adebayor's knock down from two yards out to level the scores.