Dineen, obtained from the Hartford Whalers on Wednesday for Murray Craven and a 1992 draft pick, scored into an empty net with one second remaining.
The Flyers took a 1-0 lead at 6 minutes, 38 seconds of the first period. Edmonton defenseman Dave Manson tried to clear a rebound up the slot. But Philadelphia's Andrei Lomakin gathered in the clearing attempt and scored his sixth goal of the season, beating Oilers goalie Bill Ranford, who was scrambling to get back into the net.
The Flyers made it 2-0 at 8:22 of the second after going the first 8:15 of the period without a shot. Manson over-skated a puck in his zone and Ricci picked up the loose puck and fed Rod Brind'Amour, who was alone in the slot. Brind'Amour beat Ranford low to the glove side for his fifth goal.
Vincent Damphousse's goal made it 2-1 3:17 later on the power play. Philadelphia's Pelle Eklund lost the puck trying to take more time off the penalty, and Joe Murphy, Craig Simpson and Damphousse broke in on a three-on-two. Simpson passed to Murphy, who centered the puck in the slot to Damphousse for his fifth goal of the season.
Philadelphia center Steve Kasper suffered a hyper-extended right knee in the opening period. Kasper tried to skate for a shift in the second period, but fell trying to make a turn and was helped from the ice again.
Philadelphia goalie Ken Wregget, who entered the game with a 2-11-1 career record against Edmonton, saw his first regular-season action since Oct. 17.
The victory was the Flyers' first this season when scoring three goals or fewer.
The loss dropped Edmonton to 3-9-1 on the road this season.
Edmonton....... 0... 1... 0... --... 1
Philadelphia... 1... 1... 1... --... 3
First period--1, Philadelphia, Lomakin 6 (Samuelsson, Ricci), 6:38.
Second period--2, Philadelphia, Brind'Amour 5 (Ricci), 8:22. 3, Edmonton, Damphousse 5 (Murphy, Simpson), 11:39 (pp).
Third period--4, Philadelphia, Dineen 5 (Brind'Amour), 19:59 (en).
Shots on goal--Edmonton 8-8-4--20. Philadelphia 8-8-12--28. Power-play opportunities--Edmonton 1 of 3; Philadelphia 0 of 5. Goalies--Edmonton, Ranford, 5-8-3 (27 shots-25 saves). Philadelphia, Wregget, 2-2-0 (20-19). A--17,035.