Philadelphia had a 106-101 lead with two minutes left in regulation, but Detroit rallied to tie the score, 107-107, on a tip-in by Laimbeer with 35 seconds left.
Julius Erving missed a last-second shot that would have won the game for the 76ers.
In the overtime, Laimbeer scored on an 18-footer and Isiah Thomas connected on a three-pointer to send the Pistons ahead, 112-107.
Laimbeer hit another 18-footer to make it 114-107 with 2:26 left, and added two more field goals and a free throw.
Thomas added 29 points for Detroit and Vinnie Johnson had 26.
Maurice Cheeks scored 31 points for Philadelphia.
76er forward Charles Barkley left the game to go to an area hospital for treatment of a infected elbow, a team official said.
Barkley, who injured the elbow in Sunday's NBA All-Star game, played with his arm heavily taped. He played 22 minutes and had 6 points and 4 rebounds.
Washington 133, San Antonio 108--Moses Malone scored 32 points, including 17 in the third period, to power the Bullets past the Spurs at San Antonio.
San Antonio, which trailed the entire game, pulled to within 111-100 with eight minutes left, but Washington scored 13 straight points to wrap up the victory.
John Lucas, who scored 27 points, and Junior Bridgeman each scored 6 points in the 17-point surge that brought the Bucks from behind to a 90-79 lead with 1:16 left in the third quarter.
Person hit 18 of 23 shots from the floor, including all 6 attempts from three-point range.