Daniel Sprong and Yan Pavel Laplante scored in regulation for the Islanders (4-0-0).
Marcus Cuomo and Nathan Noel scored for the Sea Dogs (2-1-1), who trail the Islanders by three points in the Maritimes Division.
Eric Brassard made 34 saves for Charlottetown, while Sebastien Auger stopped 38 shots for Saint John.
SCREAMING EAGLES 5 MOOSEHEADS 2
At Sydney, N.S., Clark Bishop had two goals and Cape Breton scored five consecutive times in a 5-2 win over Halifax.
Julien Pelletier, Cameron Darcy and Raphael Corriveau also scored for the Screaming Eagles (1-2-1) while Alex Bureau made 25 saves.
Nikolaj Ehlers and Andrew Shewfelt scored for Halifax (1-3-0), while Zachary Fucale stopped 31 shots.
Trailing 1-0 after the first period, Bishop's first goal just 18 seconds into the second period kick started Cape Breton's offence.
WILDCATS 7 TITAN 2
At Moncton, N.B., Christopher Caissy scored twice as the Wildcats mauled Acadie-Bathurst.
Garrett Johnston, Conor Garland, Ryan Penny, Will Smith and Mark Simpson also scored for Moncton (2-2-0).
Dominic Beauchemin and Adam Chapman scored for the Titan (2-2-0), who allowed four Wildcats goals in the second period.
Alex Dubeau made 22 saves for Moncton, while at the other end of the ice Jacob Brennan stopped 29 shots.
DRAKKAR 6 SAGUENEENS 3
At Baie-Comeau, Que., Philippe Cadorette made 28 saves as the Drakkar overcame Chicoutimi.
Gabryel Paquin-Boudreau, Jeremy Gregoire, Robbie Graham, Francis Turbide, Frederic Gamelin and Felix Girard scored for Baie-Comeau (2-1-1).
Charles Hudon, Victor Provencher and Sebastien Sylvestre replied for the Sagueneens (3-1-0).
Domenic Graham did what he could in Chicoutimi's net with 39 saves.
REMPARTS 6 OCEANIC 2
At Rimouski, Que., Adam Erne scored a hat trick to lead the Remparts past the Oceanic.
Erne scored a goal in each period for Quebec (1-2-1), while Anthony Duclair also scored twice and Ryan Culkin added one. Francois Brassard made 30 saves in net.
One of Duclair's goals came on a penalty shot at 7:18 of the third.
Anthony DeLuca and Michael Joly scored for Rimouski (2-2-0) while Philippe Desrosiers allowed four goals on 17 shots. He was replaced by Zachary Fortin, who stopped six of eight.
PHOENIX 5 VOLTIGEURS 2
At Sherbrooke, Que., Tim Wieser's third-period goal broke a 2-2 tie and the Phoenix offence did the rest.
Cole Murphy, William Couture, Jean-Francois Plante and Jeremy Roy also scored for Sherbrooke (1-3-0).
Jerome Verrier and Georgs Golovkovs had goals 1:10 apart early in the third to tie the game for Drummondville (3-1-0) before Wieser's goal.
Francis Desrosiers made 39 saves for Sherbrooke while Louis-Philip Guindon replied with 34 saves for the Voltigeurs.