United had created the better chances over the course of 90 minutes, but the game was swung by a moment of madness from Town's goalkeeper Paul Taylor.
With Leon Gutzmore missing from the team, Kevin Mealor was deployed as a makeshift striker, and to good effect as he linked up well at times with his partner Luke Melisi.
The visitors had the first effort at goal in the third minute, when Neal Perrin picked up the ball and fired for goal, but Tom Vincent was behind the effort all the way.
Wideman Perrin was Dunstable's main attacking threat throughout the match, and on this evidence it was difficult to see how they'd put five past Rothwell on the previous Saturday with their strikers largely ineffective.
Melisi should have opened the scoring when he was played in by Matt Butler leaving him one on one. Taylor made himself big in goal and won the duel by saving his low shot.
At the other end Carl Kavanagh was penalised for holding his man, and Perrin fired a free-kick towards the top corner which Vincent dealt with well.
Melisi went close again midway through the half when he was put clean through, the unlucky striker seeing his shot rebound off the post.
His fellow striker Mealor had the next chance when Butler slipped a quick free-kick into his path but his shot on the turn lacked the power to beat Taylor.
Aylesbury continued to dominate play for the remainder of the half. Silvestri's shot from a corner kick had to be saved by the outstretched leg of Taylor, before Melisi again threatened - this time driving the ball just wide having broken away.
Then in the final minute of an entertaining opening spell Silvestri lifted a shot wide of the target, before the whistle sounded for the interval.
Half-time: Aylesbury 0-0 Dunstable
Both sides continued to fight a good battle after the break, Dunstable having the first shot when Stephen Pratt hit a swerving shot that Vincent fielded well.
A Liam Smyth right-wing free-kick was just too high for Mealor to direct goalwards, before Perrin went close for the visitors with an effort which went all the way across goal.
Another searching free-kick delivery from Smyth this time picked out Kavanagh, who headed over the bar, before a third two minutes later was headed wide by Mealor.
Then came the game's turning point. The race was on for a through ball between Smyth and Taylor, Smyth reaching the ball first before in a moment of madness the Dunstable stopper wrestled the Aylesbury man back, just inside the area.
Referee Mr Field awarded a penalty and gave Taylor his marching orders, Matt Baldry donning the gloves and taking over in goal. His first task was to pick the ball out of the net, after Silvestri calmly rolled the ball home. 1-0 Aylesbury
Despite the double blow, Dunstable rallied, and after a triple substitution they began to have a go at equalising against an increasingly nervous looking Aylesbury.
Though they had plenty of the ball, the visitors were lacking sharpness in front of goal. The closest they came was a sweetly struck dipping volley which had to be dived on by Vincent.
Perrin also had another chance, but he shot tamely when well positioned and the ball was easily gathered in.
Aylesbury survived though, and they put the game out of Dunstable's grasp a minute from time. Substitute Ben Stevens whipped in a deep cross, which found fellow sub Justin Gordon whose shot rebounded off the shin of Baldry into the path of Melisi, who tapped into the empty net. 2-0 Aylesbury
The Ducks visibly relaxed and in the closing stages played some excellent football. Some great link up play between Mealor and Silvestri saw the latter eventually shoot wide.
Stevens then came close to grabbing a goal for himself when he arrived at the back post to head Mead's free-kick towards the top corner, but for Baldry to extend a glove and keep the ball out.
With that an end was brought to United's busy festive schedule, and a win which takes them above Dunstable in the table and up to 6th place going into the New Year.