Zdeno Chara became the third of four Bruins to score his first goal when he buried the tie-breaker 7:07 into the third period, spoiling the first two-goal NHL game of Islanders forward Keith Aucoin's career.
Shawn Thornton and Gregory Campbell scored their first goals prior to the Chara score, and Patrice Bergeron added his later in the third period. The Bruins now have 11 goals from nine different players this season.
Rookie defenseman Dougie Hamilton recorded two assists for his first NHL multi-point game.
Chara, who possesses the NHL's hardest slap shot, beat DiPietro through a screen with a wrist shot from the high slot. The Bruins' top line cycled the puck down low until Milan Lucic made it to the bottom of the right circle and found Chara open and waiting for a pass.
Just two nights after his ice time was severely cut in a road loss to the New York Rangers, Thornton began to earn more action with a goal against the Islanders. It took 4:52 for Thornton to get the Bruins on the board with help from Hamilton, who rifled a shot from the right point toward the slot. The puck was knocked down and Thornton flipped it into the back of the goal with a backhand shot.
The Bruins' lead lasted until a defensive breakdown led to Aucoin's first goal. With four Bruins focused on David Ullstrom, the Islanders forward moved the puck to linemate Colin McDonald, who then fed it out front to Aucoin all alone in front for the goal that tied the game 1-1 at 11:13.
Boston outshot New York 14-11 in the first 20 minutes.
Aucoin continued to impress the team he joined last week on waivers from Toronto with his second goal of the night, and third in two nights, at 9:50 of the second period to give New York its first lead of the night. Daniel Paille's clearing attempt from the corner slid up the middle of Boston's zone and Aucoin hammered it over Rask's catching glove for a 2-1 edge.
For the second time in the game, the Bruins' fourth line then scored. This time it was Campbell, who was parked in front of the net when David Krejci spun and fired a shot from the left-wing half boards. Joe Finley blocked the shot right to Campbell, who fired it inside the right post to even the score at 2-2.