When I took Ruffio to get neutered in December, the vet looked at his teeth and determined he had 6 teeth that needed to be pulled. His canines where growing in behind his baby canines, and if they were left they would have started hitting the roof of his mouth. So he ended up getting neutered and 6 teeth pulled since he would be under already.
But it is up to you whether to leave them or not. I would maybe get a second opinion to make sure leaving them is not going to cause any problems.