The Ghana international, who is currently out of action with a knee injury, maintains that the Italy captain should have informed the officials that the ball had crossed the line
The Rossoneri were already a goal to the good when the Ghanaian appeared to have doubled the home side's advantage with a close-range header.
However, the match officials failed to notice that the ball had travelled approximately a metre over the line and Juventus ultimately went on to claim a precious point thanks to a late goal from Alessandro Matri.
Muntari does not buy into the theory that the decision effectively cost Milan the title, but nonetheless continues to feel let down by Buffon's conduct that night.
"He saw that the ball was clearly over [the line]," the midfielder told Tuttosport. "I have no idols in football. However, I thought that Buffon was a champion of fairness.
"I know that the ball was over the line. But he also knew, immediately.
"I have always thought that if they had given that goal we could have won the game, but still maybe lost the championship. Or, conversely, we could have lost to Juventus and then won the championship anyway.
"But we're looking ahead and thinking about winning the next title."
Muntari is currently out of action with a knee injury sustained while on holiday earlier this summer, and it had been speculated that the Ghana international may not play again this year. However, he insists otherwise.
"I'm sure that I will return in 2012," the former Inter man stated. "You'll see. I'm working every day, with a great desire."
Muntari also expects Milan to be fighting for the title upon his return to the side, despite the loss of key duo Thiago Silva and Zlatan Ibrahimovic.
"They were important players and it will not be easy to replace them," the 27-year-old conceded.
"But [Ariedo] Braida and [Adriano] Galliani have the experience to succeed [in that regard]. They already have alternative plan ready. Milan will return to the top."
Muntari, who has been capped 74 times by his country, joined Milan on loan from Inter during the January transfer window but made his move permanent earlier in the summer.