Ian Madigan's 18 points helped Leinster edge out the Dragons in an entertaining Pro12 clash at the RDS.
Leinster's first-half tries from Andrew Conway and Ben Marshall were split by Steffan Jones' Dragons score as the home side led 26-13 at the break.
Shane Jennings and Fionn Carr touched down to secure Leinster's bonus point with Tom Prydie and Dan Evans replying with Dragons tries.
Brendan Macken's injury-time try rounded off Leinster's victory.
The Dragons, looking for their first win in Ireland since 2008, took an early lead thanks to a Prydie penalty before Madigan quickly levelled.
From the restart, Noel Reid's break set up Leinster's first try for Conway with Madigan adding the conversion.
However, the Dragons hit back to level with Jones running in a try after intercepting a Reid pass.
Madigan and Prydie swapped penalties before another three points from the Leinster fly-half and Marshall's try gave the home side some breathing space.
The Dragons had prop Nathan Williams sin-binned late in the first half and Leinster exploited their numerical advantage in the opening minutes of the second period as Jennings and Carr notched tries in quick succession.
Leading 38-13, Leinster then began to lose their way as a Dan Evans break set up Prydie's try.
More Leinster sloppiness enabled full-back Evans to score a try of his own in the 59th minute as he outpaced Isa Nacewa after Prydie's break.
Having cut Leinster's lead to 38-25, the Dragons produced more late pressure but the home defence was resolute and Macken broke from his own half in injury-time to round off the Irish province's win.
Leinster: Isa Nacewa, Andrew Conway, Brendan Macken, Noel Reid, Fionn Carr, Ian Madigan, John Cooney; Jack McGrath, Sean Cronin, Jamie Hagan, Leo Cullen (capt), Quinn Roux, Ben Marshall, Shane Jennings, Leo Auva'a
Replacements: Tom Sexton for Cronin 61 mins, Heinke van der Merwe for McGrath 51, Martin Moore for Hagan 67, Devin Toner for Roux 61, Jordi Murphy for Jennings 61, Luke McGrath for Cooney 72, Jordan Coghlan for Auva'a 72, Darren Hudson for Madigan 75
Dragons: Dan Evans, Will Harries, Pat Leach, Andy Tuilagi, Tom Prydie, Steffan Jones; Jonathan Evans; Nathan Williams, Sam Parry, Nathan Buck, Ian Nimmo, Adam Jones, Hywel Stoddart, Jevon Groves (c), Toby Faletau
Replacements: Hugh Gustafson for Parry 51, Aaron Coundley for Williams 60, Tim Ryan for Buck 72, Lewis Evans for Stoddart 54, Tom Brown for A Jones 67, Liam Davies for J Evans 72, Ashley Smith for Tuilagi 74, Hallam Amos for S Jones 65.
Referee: Marius Mitrea (FIR).
Assistant Referees: Mark Patton, Jonathon Peak (both IRFU).
Citing Commissioner: Tom McCormack (IRFU).
TMO: Alan Rogan (IRFU).