LEINSTER secured an eighth straight victory thanks to an unstoppable first-half performance at Rodney Parade.
Joe Schmidt's men tore the shellshocked Dragons to shreds and raced into a 16-point lead, with Sean Cronin crashing over for a double and Dave Kearney also racing clear.
Steffan Jones reduced the deficit to 10 points at the break and the Dragons continued their comeback in the second period with a Ieuan Jones try.
However, Leinster rediscovered their groove to quell the home side's fire, with Kearney claiming his second touchdown to wrap up the bonus point.
Home out-half Jones scampered over for a try at the death, but it was merely a consolation for the spirited Dragons.
The victory sees the Dubliners keep the pressure up at the top of the Pro12 table and they welcome table-topping Glasgow to the RDS next.
Ireland assistant coach Mark Tainton made the trip to Newport to cast an eye over five returning internationals, including most notably Fergus McFadden and Ian Madigan.
Luke Marshall was one of the few shining lights in Ireland's dismal 12-8 defeat to Scotland, but with an extensive injury list, McFadden could force his way into the match-day squad.
And the Kildare centre did his chances no harm with a commanding performance in which he created the second-try.
McFadden does not possess the array of ball-handling skills Marshall does, but he demonstrated deadly passing for the try and was rock solid in defence.
Madigan was also impressive and staked a claim for the Ireland No 10 jersey.
With Jonny Sexton a doubt for the clash with France, Declan Kidney has a selection headache.
Both Paddy Jackson and Ronan O'Gara struggled in Murrayfield and Madigan may have made his decision even more difficult with an imperious performance. He controlled proceedings with aplomb in Newport and superbly converted three of the four tries.
Schmidt's men went into the clash on the back of seven straight victories and they continued their winning run with ease. The Dragons lost their last home encounter to a record 60-3 against Warriors and while they made some amends with a shaky 14-13 victory over Zebre, they were comprehensively outplayed here.
It may have been St David's Day, but the Dragons gave the Rodney Parade crowd little to cheer.
Leinster were boosted by the return of five Irish stars and their experience, class and ultimate superiority was clear from the outset. It took them just 50 seconds to open the scoring with Luke Fitzgerald releasing Cronin on the overlap and Madigan expertly converting from wide left.
Jones responded for the Dragons but their resurgence was shortlived as Cronin dived over for his second try on six minutes. McFadden was the architect, on this occasion providing the brawn with a midfield burst and the brains with a pinpoint pass for the former Connacht hooker to touch down on the same spot.
Madigan failed to convert, but Leinster continued to run riot. They claimed their third try on 18 minutes as Rhys Ruddock powered through two men off the back of a dominant scrum and superbly off-loaded to the onrushing Kearney.
Madigan's radar was back on target and he stretched the scores to 19-3 as the encounter approached the second quarter.
Jones added his second penalty on the half-hour mark after a rare venture into the Leinster half and he quickly knocked over a drop-goal as the hosts fightback continued.
Schmidt's men threatened to wrap up the bonus point, but the Dragons, possessing new-found confidence, weathered the storm and the scores remained 19-9 at the interval.
The Dragons continued their revival after the break and they demonstrated far more fire and passion in the second half. Leinster did themselves no favours by spilling the ball from the restart and, following a sustained period of pressure, Jonathan Evans sent Ieuan Jones flying over.
His namesake Steffan failed to add the extras, but they continued to battle.
However, they got back on track and landed a knockout blow in the 65th minute when Kearney was on the receiving end of a sweeping move to claim his second try.
Madigan converted before Steffan Jones crashed over to salvage a losing bonus point for the hosts.