... an adult has 32 teeth 16 on top 16 on the bottom. babies have 20 until around 6 years when another molar comes in. then the baby molars fall and premolars come in their place :)
about 20 they start coming out at about 6 moths. they will all fall out bout when your 14 or 16, and replaced by permanent teeth. http://www.intelligentdental.com/2010/02/22/dental-care-for-babies/