I nursed DS1 until he was 3.5 and co-slept so there was definitely night-nursing. He just had his first dentist appt a few months ago and the dentist said he had "great looking, super healthy teeth" so apparently all those years of night nursing didn't do any harm
Also, it sounds like that Dr is letting her own personal feelings about extended BFing influence her professional views. Very unprofessional IMO. In addition, as I continued to BF DS1 I heard more and more stories from moms I knew who had extended nursed their kids too. I think more people do it than most people realize, but people are often so rude about it that moms keep their extended nursing to themselves.
Sounds like you are doing a great job mama
Mama to Kostas with the Mostest, born 07/10/07
and Marek "Cricket" Joshua, born 12/07/12