Root canal- should dentist have to drill to put on permanent crown a month later?

[Mikemckula]

Hi.  I had a root canal done on a tooth bottom right side of my mouth.  I've had root canals in the past and assumed and have been told putting the crown on is an easy, relatively painless procedure.  I've had to go back 3 times since root canal trying to get the permanent crown to fit.

I've been to him twice and both times he's taken a drill to the original tooth(without novacaine).  He claims he is just doing this to clear the glue, debris from the temporary but it didn't seem normal to me.  

First question:  Is it normal to have to drill around what I guess is referred to as the "post" months after a root canal?

Second question:  Should it be that difficult to get the permanent to fit properly.  This is the third impression he has taken?

Third question:  Is it possible that he didn't take the original tooth down far enough when he did the root canal and that is making it hard to find a permananent crown that doesn't sit too high??  I've noticed on previous canals the original tooth was taken down near the gumline.  This was was a nub and considerably higher.

He acts as if there is simply something wrong with the impression but I sense there is something more to it.  Any advice/help would be GREATLY appreciated.  Thanks so much in advance.

[Jerome Bogin, D.D.S.]

I have been in practice for over 40 years and I would be fibbing if I said that every crown that I took an impression for fit the first time, but it is a rare occurrence, and certainly having to impress it three times does sound excessive.I can't comment on the doctors technique so I guess you have two choices, one is to hang in there until it gets done or seek out another dentist.

[Mikemckula]

Thanks so much for your response.  If you could try to quantify, how rare would you say it is for a dentist to have to take a second impression of a crown in percentage terms?  Thanks again.