I took my daughter at age2 only because she hit her front teeth on the pew(seatbench) at church and her teeth turned off white which indicates nerve damage. I took her to a pediatric dental office in Edina. They looked around in her mouth took xrays and that was about it.
I then started taking my daughter regularily for regular checkups at age3.At that time we switched to Metropolitan Pediatric Dental in Eagan I believe they have a office in St.Paul as well. She had 3 cavaties already and I'm glad I took her then. My child has inherited her father's teeth and has had alot of hereditary problems. I knew she wouldn't do well with a regular dentist so we've had alot of positives with a pediatric one. I've seen kids go in and get teeth pulled or cavaties and come out laughing and smiling. Keep in mind your lil one could love it or hate it. The littlest things set my child off. She freaks out having her teeth polished which doesn't hurt but will sit nicely and have a filling put in.
Personally I wouldn't bring your child in til they have most or all of their teeth in around age3. Unless you notice a problem ahead of time.
Where we go they have the child watch a video their first time about going to a dentist or something. Then the lady takes you in a room where they ask you medical questions or if anything is a concern and she let's the kids squish around the red stuff that sticks to the teeth so they know where problem areas are. Then the parents sit behind a glass wall as the children are in another room. They have like 6 kid size dental chairs where the kids go and each child has a dental hygentist and the actual dentist makes his rounds to everyone. All in one room. Like I said with us parents behind a glass wall watching. If your child is scared or little they will let you go in with them. But sometimes they do better without mommy right there. They have things painted on the ceiling for the kids to look at and it's really fast and quick. Then they get to pick a prize.