Tooth eruption commonly starts at around 6 months, but it's an extremely variable milestone. Some babies are born with a few teeth, while other children have nothing to show even at a year. Children with a general developmental delay may have delayed teeth too, but as long as your pediatrician feels your baby is growing normally otherwise, there's nothing to be concerned about. The American Academy of Pediatric Dentistry recommends that babies have their first appointment six months after their first tooth and no later than their first birthday, even if no teeth have come in, so it's time for that step, which will also help rule out any potential problems.
Originally published in the April 2007 issue of Child magazine. Updated 2009