This question arises to many persons minds if we have third set of teeth? How many Teeth we have? Till what age teeth keep erupting? At what age teeth shed? etc etc. Let me shortly explain you the doubts.
Teeth erupt only twice in a lifetime i.e. we have only two set of teeth.
a) MILK TEETH (DECIDUOUS / PRIMARY)
The development of these teeth begins while the baby is in the mother's womb. At around five weeks pregnancy, the first buds of milk teeth appear in the baby's jaws. At birth, the baby has a full set of 20 milk teeth (10 in the upper jaw & 10 in the lower jaw) hidden within the gums.
Milk teeth start erupting from 6 months after birth & the eruption completes at around 30 months of age.
Milk teeth start shedding from the age of 6 years till around 10-12 years of age.
b) PERMANENT TEETH (SECONDARY):
This is the second set of teeth. This is God's gift which He has made it such that they can be used for a lifetime. This consists of 28 to 32 teeth. Additionally some supernumerary teeth may be present of even some teeth may be congenitally missing.
Permanent teeth start erupting at the age of around 6 years & the eruption completes at around 12-13 years of age.
Third molars i.e. wisdom teeth erupt anytime after 17-23 years of age.
So it is highly important to take good care of both primary and secondary dentition for a healthy being.