Has an NCAA Men's Basketball game ever ended 56-45?
It has. 56-45 has been a NCAA Men's Basketball final 22 times in 136,843 games. The first was Harvard Crimson beat Stony Brook Seawolves on November 30, 2002; the latest was Sam Houston Bearkats beat California Baptist Lancers on February 23, 2023.
That makes 56-45 the 1196th most common final score out of 3,845 that have ever occurred in NCAA Men's Basketball. One point away, 57-45 has happened 25 times and 56-46 has happened 38 times.