Boston's first win of the season came thanks in large measure to a 36-point third quarter, during which Pierce hit two 3-pointers.
Pierce missed the Celtics' first three games, all losses, with a bruised right heel. He was in the starting lineup Friday and scored 12 points while playing 23 minutes.
The Celtics had a seven-point lead at halftime and then outscored the Pistons by 15 in the third period.
Greg Monroe had 22 points for Detroit, which has lost all three of its contests this season.
Boston shot 52 percent from the field and made all 19 of its attempts from the foul line.