Both players have been out for about a month. Carter suffered a broken foot on April 20 and Laperriere a concussion and brain contusion on April 22. Laperriere was thought to be probable for Game 4, but Carter wasn't expected to be ready until at least Game 5.
The Flyesr get both players back in time to try to take a 3-1 series advantage over the Canadiens. Game 5 of the series will be played on Monday night in Philadelphia.
After being outscored by a 9-0 margin in losing the first two tests of this best-of-seven series in Philadelphia, the eighth-seeded Canadiens stormed back on home ice with a decisive 5-1 victory in Game 3 on Thursday.
Thursday's loss was the most lopsided setback of this postseason for the Flyers and was also the club's worst defeat since dropping a 6-0 decision to Pittsburgh in the fifth and final game of the 2008 Eastern Conference finals.
In Game 3, Jaroslav Halak stole some of Philadelphia goaltender Michael Leighton's thunder, making 25 saves to anchor Montreal's impressive victory at Bell Centre. The rest of the Canadiens finally solved Leighton, who registered consecutive shutouts by turning away all 58 shots Montreal had fired at him in the first two games of this series.
"(Halak) made some big saves early in the game," said Montreal head coach Jacques Martin. "I think that (Philadelphia) had three chances in the first five minutes of the hockey game. Then after that I think our team kind of took over and played a strong game at both ends of the ice."
Montreal has been resilient this postseason, rallying from a 3-1 series deficit against Washington and a 3-2 hole against defending champion Pittsburgh in Round 2.
"We moved the puck much better tonight," Gionta said. "We entered their zone a lot better tonight. Our forecheck was good."
Cammalleri's goal was his 13th of this playoffs, placing him fourth on Montreal's franchise list for most tallies in one postseason. Frank Mahovlich is next on the list with 14 goals in the 1971 playoffs.
For the Flyers, Simon Gagne scored the lone goal when he tallied in the third period. Philadelphia also lost for the first time since Game 3 of its conference semifinal matchup with Boston, which held a 3-0 series' lead before the Flyers rallied for a historic comeback. The Flyers had outscored the opposition 24-8 during their six-game win streak.
Meanwhile, Leighton, a journeyman goalie claimed off of waivers by Philadelphia for the second time in his career back in December, had won four straight since taking over the starting job after Brian Boucher hurt both knees during Game 5 against Boston.
The Ontario native, who turned 29 on Wednesday, finished with 33 saves.
"I'm not going to dwell on them scoring that many goals. We know we have to play better defensively and offensively," Leighton said.
Philadelphia and the Habs are battling for the East title despite being the bottom two seeds in the conference, marking the first time since the NHL adopted its current playoff format in 1994 that the seventh and eighth seeds in either conference are playing a series with a trip to the Stanley Cup Finals on the line.
The Canadiens are 4-3 on home ice during the postseason after going 20-16-5 at Bell Centre in the regular season. Philadelphia had a poor 17-21-3 record as the guest this season, but is 4-4 on the road in the playoffs.
The Flyers and Canadiens are meeting in the playoffs for the sixth time. Montreal won three of the previous five encounters, but Philly beat the Habs in five games the last time the franchises met in the 2008 conference semifinals. Prior to that, the previous two encounters were for conference titles, with Montreal earning a trip to the Cup Finals in 1989 -- two years after Philly beat them for the Prince of Wales Trophy in 1987.