Root Canal Question

Hi, I needed a root canal on a tooth on the top of my mouth, one from the back.  My regular dentist sent me to an endodontist to do the root canal, and the endodontist is sending me back to the first dentist to get the permanent filling and crown.

My question is in regard to the crown.  Initially, I thought the endodontist was going to put in the permanent filling, I think I even remember someone there mentioning it.  Also, I remember mentioning that my initial dentist seemed to imply that needing a crown was automatic, but the endodontist seemed suprised by that and said my tooth might not need one, and that it was a 50/50 thing.  Then after the last procedure at the endodontist (I had an infection problem, because apparently the endodontist missed a passage) I found out I had to go back to the original dentist for the final filling and possible crown, and the endodontist did not want to say if I needed a crown or not.  So now I'm wondering if he changed his opinion on it because the 2 dentists have some sort of agreement with eachother, and dentist one likes to crown all root canals.  So what percentage of teeth require crowns after root canals?  I'd rather not put a crown over my tooth if I don't have to, but then again, I don't want it to crack and have to have it pulled, so I'm not sure what I should do.