LaVine also had 15 assists, and Lauri Markkanen came off the bench to score 18 points on 8-of-10 shooting.
Chris Boucher scored a career-high 38 points and had 19 rebounds for the Raptors. They have lost 15 of 18.
Pascal Siakam added 27 points and eight rebounds for Toronto.
LaVine and Vucevic combined for 15 points on an early 19-3 run that gave the Bulls their first 10-point lead.
Chicago ran off 13 straight points while the Raptors missed 10 straight shots, and a 3-pointer by Coby White made it 51-31 with 6:04 left in the first half.
Two 3-pointers and a three-point play by Boucher helped Toronto cut the margin to seven late in he fourth quarter, but LaVine closed it out with a layup and a 3-pointer with 45 seconds left.
Rookie Malachi Flynn got his first NBA start for the Raptors, who had only eight players available for the game. They signed Freddie Gillespie to a 10-day contract early Thursday, but the 6-foot-9 former G-League player had not cleared the NBA's entry protocol in time to play.
Bulls: The Bulls have not won four straight since a seven-game winning streak in December 2017. . . . F Garrett Temple (hamstring) participated in Thursday's shootaround but is not ready to sprint, according to coach Billy Donovan.
Raptors: F DeAndre Bembry sat out a one-game suspension for his part in an altercation during the first quarter of Tuesday night's game against the Lakers. G Fred VanVleet was also given a one-game suspension that will be served when he is eligible to return from the injured list. He missed his third game with left hip flexor. . . G Kyle Lowry missed a fifth game with right foot infection.
Bulls: At Atlanta on Friday night.
Raptors: At Cleveland on Saturday night.