Philadelphia (10-7) shot just 27.3 percent from long range and 43.8 percent from the field overall. Chicago moved to 6-0 when holding teams to fewer than 90 points.
"The thing for us is to concentrate on improvement," Thibodeau said. "We are moving in the right direction. We are still not a 48-minute team. There were stretches where we played well defensively, we have to do it consistently throughout the game."
The Bulls downplayed talk of the rematch from last season's early playoff exit throughout the week. But the memory clearly lingered with fans, who showered the Sixers with boos during introductions.
The Bulls lost reigning MVP Derrick Rose to a torn anterior cruciate ligament in the final 90 seconds of a Game 1 win over the 76ers. Chicago exited the first round in six games, just the fifth time in NBA history a No. 8 seed knocked off the No. 1 seed. Rose had surgery to repair his left knee in May and has been rehabbing since.
Philadelphia jumped out to an early 13-6 lead before the Bulls found a rhythm on offense.
Deng assisted Noah on a big first-quarter dunk to bring Chicago within two points, then was on the receiving end two possessions later with a dunk to tie it at 17.
Deng scored Chicago's final seven points of the first quarter to contribute to a 21-6 Bulls run.
Philadelphia regained the lead with a minute left in the second half on Evan Turner's fading leaner in the lane. Following another dunk by Noah, Holiday hit one of two free throws with 1.3 seconds left to send it to halftime tied at 41.
Notes: 76ers guard Nick Young (left great toe hyperextension) was inactive. ... Turner reached double digits in scoring for a ninth straight game, extending his career high.