Did you know that babies only have 20 teeth, but adults have 32? Between gaining the first set of baby teeth, losing those, then replacing them with adult teeth — it’s a lot of transition for your kiddos. Here’s exactly what to expect… Those little chompers Babies will eventually have a total of 20 baby teeth, with 10 on the top and 10 on the bottom. In pediatric dentistry, we refer to baby teeth as primary teeth. These primary teeth usually erupt from six months to age two.