C.M.
Both the American Academy of Pediatric Dentistry www.aapd.org and the American Academy of Pediatrics www.aap.org advocate for "first tooth or first birthday". It seems early but it reallly establishes good oral care and your child use to someone's fingers in their mouth. They won't do much the first visit but it's helpful. Check out the AAPD's web site www.aapd.org for a pediatric dentist in your area - they also have a good parent FAQ section.
Good luck!