I've been taking my daughter (almost 3 yrs. old) to Dr. Daniel King in Alpharetta for about a year or so - He's great, young and very friendly (non-threatening to little ones). The office is amazing as well. My daughter loves the waiting room (video games, movies, fish in aquarium, etc.). Great atmosphere, extremely friendly staff!!
3719 Old Alabama Rd Ste 400
Alpharetta, GA 30022
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It's in Alph/Johns Creek by Old Alabama Rd & Jones Bridge Rd. (not too far from Haynes Bridge Rd.) I think the practice is called Children's Dental Zone.
It may be a bit out of your way, but I had to recommend him - he's great. Good luck!
PS - the first time we went, my daughter didn't have dental insurance and I think I paid under $100 for the whole check-up.