And after Joshua Furno had gone over for Aironi, Andrew Coombs replied for the hosts for their first win of the season, leaving the Italians bottom of the table.
Two away games had failed to bring any cheer to the Dragons but a return to familiar surroundings got off to the perfect start when a flowing move from left to right saw Riley squeeze over, Jason Tovey adding the extras.
Aironi thought they had touched down a try off their own on 12 minutes following a scrum but the replays proved inconclusive, Tovey rubbing salt into the wounds with a penalty seven minutes later.
And things went from bad to worse for Aironi on the half hour, Nick Williams seeing a yellow card and Tovey duly popping over the resulting penalty.
But just when things looked bleak before half-time, Naas Olivier finally got the Italians on the scoreboard with a 37th-minute penalty.
The first bit of action in the second-half saw the returning Martyn Thomas chase on to his own kick and touch down, only for the TV referee to judge that Aironi's Tito Tebaldi had grounded the ball just before.
And buoyed by this decision Olivier went up the other end and kicked another penalty before Furno went over on 62 minutes to bring the scores to within just two points at 13-11.
But that was as close as Airioni got as just five minutes later the Dragons were rewarded for their patient play, Coombs going over in the right corner to pad out their lead once more.
Olivier and replacement Matthew Jones traded penalties late on as the Welsh side saw out a comfortable victory.
|Newport Gwent Dragons Score Card|
|Aironi Rugby Score Card|